It’s been a while since I’ve had a chance to post. Things got a little hectic toward the end of my stay in Tonga, and my re-entry into urban life has been as chaotic as usual. But I’ve finally settled back into (some semblance of) a normal routine, and I’m hard at work catching up on my to-do list mountain.

Final Calf Encounter
Before departing Tonga, I was fortunate enough to have one last encounter, with a humpback whale calf that I had not come across before…Fanima (female), the 45th(!!!) calf of the season.

Fanima was a big baby when I met her. I estimate that the mini-Megaptera was close to half the length of her mother, which suggests that she was born early in the season.

Perhaps in part because the calf was relatively mature, mom was laid back. She seemed, in fact, almost entirely unconcerned with what the little one got up to. Fanima played and splashed at the surface with considerable vigour, executed many a whimsical twirl, checked the boat out on multiple occasions, and peered with intense curiosity at anyone in the water.

Fanima (calf #45) was my final calf encounter for the 2011 season.
Given her relatively large size, Fanima was probably born early in the season.

We did, however, have a bit of drama.

Before I had a chance to take any photos, an escort appeared without warning out of the deep, surging up beneath Fanima’s resting mother, waking the female from her slumber. Not surprisingly, Fanima’s mom bolted, with calf in tow. Females of any species…as it turns out…don’t enjoy being taken by surprise.

When escorts approach suddenly like this, relaxed mother/ calf pairs often take off and swim at high speed for considerable distances.

I was alone in the water at the time, and groaned in despair at the prospect of having lost the opportunity to ID the calf.

Fortunately, mother and baby settled again after only a few minutes. Mommy, it seems, decided that she liked the escort and let him stay. Whew! I’ve seen this happen before, but less often than I’ve seen the swim-swim-swim-away scenario play out.

With that, we spent a wonderful hour or so cavorting with Fanima, mother and escort…a perfect way to wrap-up an incredible season of humpback whale encounters.

Humpback whale calf Fanima having fun swimming upside-down

Incredible Season
2011 was my tenth humpback whale season in Tonga, my ninth consecutive one.

It was also the most amazing. I think I learned more about humpback whale behaviour over the past two months than I have in all the other seasons combined!

The relatively high number of whales this season was certainly a big factor. After all, the more whales there are, the more there is to see.

But I think the cumulative weight of previous experience may have tipped the scales as well. Bits and pieces from seasons past seemed to fall into place, affording me a glimpse of the bigger picture…like the moment when a jigsaw puzzle finally coalesces.

I’m still processing everything I experienced and learned this season, but here are some key points that come to mind:

Record number of baby whales: To date, I’ve ID-ed 45 humpback whale mother/ calf pairs. My previous record was 31 mother/ calf pairs in 2009, set out in this file: humpback whale calf count file for 2009.

I have to double-check the IDs to make sure I didn’t double count, but I have a reasonably high degree of confidence in this tally, given the many(!) hours I’ve invested squinting at the finer details of whale body patterns, dorsal fins, flukes and other markings. Of course, I’m hoping to receive additional data that will increase the final count, but in any event, I’m 100% certain that there were many more babies in the area.

Record-breaking mother was a repeat from 2009: The mother that broke the previous high count of 31 was a female that I had previously ID-ed with a calf in 2009. The female in question was the mother of Luna (calf #13, female, in 2009) and returned this season with Toluua (calf #32, female). I recognised the mom on sight because of her unique dorsal fin, but also…more interestingly…because of her personality/ disposition. See Part 5 for a discussion of this inspiring encounter.

This is now the third female I’ve documented returning with a second calf. There might be more repeat mothers in this year’s crop. I just haven’t had time to do a methodical comparison yet.

Worst visibility ever: The underwater visibility this season was consistently the most mucked-up and worst that I’ve experienced to date. There have, of course, been periods of poor visibility before, but the less-than-ideal conditions persisted for the entire season. Visibility was poor far offshore as well, in areas that would be clear under more normal circumstances.

I have no idea what caused this prolonged phenomenon. I’m guessing it’s a lingering effect of the prolonged El Niño/ La Niña cycle that finally ended a while ago, but really…who knows?

Earliest whales ever: Somewhat offsetting the bad visibility was the fact that the whales showed up as early as I can recall. I wasn’t in Tonga at the time, but I received reliable reports of whale sightings in June, with the first babies spotted in late June. To put that in perspective, I usually expect the earliest humpback whale calfs to be spotted in mid- to late-July or so.

You might recall that the whales showed up relatively late last year, so this marks a stark contrast between the two consecutive seasons.

One thing I’ve been keen to see is whether the whales leave Tonga earlier than usual as a result of their early arrival in the area. We’re a third of the way through October now, and while the number of whales has declined, it seems like there are still quite a few around, as one would expect at this stage in a “normal” season. I’ve received several reports of excellent in-water encounters over the past few days.

Toluua (calf #32), who’s mom is the same as the mother of Luna, calf #13 of 2009!

Lots of whales as well: Going hand-in-hand with the early arrival of the whales was the seemingly high number of humpbacks.

Last season, it seemed as if there weren’t as many whales around as in a given “average” season. This year, there were certainly some days when there were few whales to be found, but in general, an abundance of whales characterised the season.

Go figure…Escorts are actually interesting: I’ve always considered escort whales that associate with mother/ calf pairs a bit of a nuisance. They often “push” the female/ baby whales and make them swim at high speed for prolonged periods, making it difficult to get a look in the water, much less take photos.

But I started noticing a few things about the escorts this season.

For instance, in Part 3 of my updates, I documented one escort hounding two separate mother/ calf pairs (calf #17 Tahafita and calf #18 Tahavalu) on consecutive days, with both mother/ calf pairs seemingly doing their best to get away from the pesky male in question. I named him “Two-timer”.

Two-timer’s plight was a clear contrast to the way that the presence of an escort seemed to settle Tolu’s (calf #3, male) mom, as I described in Part 2, and also to the way that Tahafa’s (calf #14, male) mom seemed to take comfort in the presence of her long-term escort, as I set out in Part 5. Recall also from the write-up about Fanima (calf #45, female) above, that Fanima’s mom only took a few minutes to accept the presence of the escort.

Perhaps this is obvious, but it seems that female humpbacks are receptive to overtures from some males, but not others.

I’ve also seen this behaviour among sperm whales, where females seem to “like” or “not like” individual adult males, so perhaps this is a universal phenomenon? (For my own good, I’ll resist the temptation to draw any parallels to human female behaviour, however obvious.)

Escort relationships can be long term: I had always assumed that escort relationships with mother/ calf pairs were relatively short term. Actually, to be more accurate, I hadn’t given the topic much thought, as ID-ing mother/ calf pairs was my priority, and escorts were just sort of “in the way”.

This season, I’ve documented two relatively long-term relationships between an escort and a mother/ calf pair.

The first involved Tahafa (calf #14, male), with a single escort staying with the mother/ calf pair for a period of at least 14 days (1 to 14 September), as I described in Part 6. The second was Faua (calf #42, female), with a single escort present from 20 September to 7 October, a span of 18 days (just received photo documentation of this latest sighting).

My understanding from communicating with researcher friends in Hawaii is that no one else seems to have documented such long-term associations between an escort and a mother/ calf pair before. (If you know of any such documentation, please clue me in!)

Perhaps this is a phenomenon unique to the whales that frequent Tonga; perhaps it’s a fluke (excuse the horrible pun); or perhaps this happens elsewhere as well, but hasn’t been documented because it’s difficult to follow a particular escort + mother/ calf for an extended period.

Of additional interest, both of these escort + mother/ calf groups travelled the 40km distance between Vava’u and Toku. Maybe having an escort around is something mothers prefer when crossing open ocean? (See discussion of Pseudorca attacks below.)

In any event, picking up on these fascinating escort/ mother/ calf dynamics has sparked my interest in escorts, and from this season forward, I’ll be keeping records of the number of escorts we see with mother/ calf pairs, as well as taking careful notes on their behaviour, and photographing them more carefully for ID purposes (just what I need…more self-imposed work!).

Tahafa (calf #14), the undisputed star of the season

Singing escorts: One other escort behaviour that has me scratching my head is singing. Most people associate singing behaviour with lone males, hanging in the blue, belting out their haunting melodies. Males can also sing while they swim. In fact, “travelling singers” seem to be nearly as common as stationary ones, at least in Tonga.

But over the years, we’ve also come across a number of males singing when they’re with mother/ calf pairs. Again, I haven’t kept meticulous records of this, but in general, this seems to take place when more than one male is involved. It can sometimes be when the whales are resting, and at other times, when the whales are swimming.

We had two such observations this season. The first was with Uataha (calf #21). Two males approached the mother/ calf pair; there was a bit of commotion; and then there was an escort with the mother and calf…singing. The whales settled in shallow water, not moving much.

The second instance involved Tahafa (calf #14, male). In this case, there were multiple males challenging the primary escort repeatedly over the course of many hours. Amid the chaos and pandemonium, at least one of the males was singing…really loud! I think it was the primary, long-term escort, but I can’t be certain. There was a lot of action, and the whales definitely weren’t settled.

What does this mean? I’m not sure, but I do know that humpback whale singing behaviour is much more complex and nuanced than a lone male crooning while hanging head-down in the water.

Escort ratio is high: One final note about escorts…the ratio of mother/ calf pairs with at least one escort present is high in Tonga. This season, out of a given 10 mother/ calf pair encounters, somewhere between 4 and 5 will have had an escort or more (I’ll have a precise figure after I review all the data). My understanding is that such a high prevalence of escorts with mother/ calf pairs is unusual.

If you think about it, escorts should prefer single females over ones with babies, on the assumption that escorts are males looking to mate.

From memory, the ratio has always been high in Tonga, but again, I haven’t kept careful records to date. I did keep careful records this year though, so when I produce my calf count summary for this season, it will include a breakdown of escort relationships as well.

More about this topic in Part 6.

Pseudorca attacks: With the combined evidence from the injuries on Tahafa (calf #14, male), Fafa (calf #44, female), Fitu (calf #7) and Uanoa (calf #20, male), the case for false killer whale attacks on humpback whale babies around Tonga seems like an open-and-shut case.

Maybe such attacks are a contributing factor to reason why there are long-term escort + mom/ calf pair relationships discussed above?

It will be interesting to see whether we come across more such attacks in the future, and also if we see these particular babies back in Tonga in upcoming seasons. Scarring should make it relatively easy to spot them, assuming they survive and also return to Tonga.

See Part 7 for a detailed discussion of the rationale for pointing the finger at Pseudorca crassidens.

Travelling mother/ calf pairs: This season, we’ve ID-ed three mother/ calf pairs that have moved between Vava’u and Toku: Tahafa (calf #14, male); Uatolu (calf #23, female); Faua (calf #42, male).

I’ve always taken it for granted that mother/ calf pairs travel, and my data from previous years has suggested that Vava’u is more of a stopover place than a long-term home, but it’s nice to have incontrovertible photographic and GPS proof.

Abundance of white pecs: Whales with all-white pectoral fins were back in numbers this season. I haven’t done a final count, but we photographed at least 10, including, for the first time, two babies with all-white pectorals fins…Uafitu (calf #27) and Faua (calf #42, male). Faua’s mom also has white pecs.

Why is this important? Because whales with all-white pectoral fins are relatively easy to spot and track, and there usually aren’t that many that visit Tonga. This is only the second season during which I’ve come across so many of them. Last year, for instance, I didn’t see any, though friends report seeing one, possibly two.

What this suggests to me is that it’s not always the same group of whales visiting Vava’u.

Dearth of split dorsal fins: Along similar lines, we only came across two whales with split dorsal fins this year. Actually, it was more like 1.5, since one of the two only had a mild split.

Why is this important? Because whales with split dorsal fins are also easy to recognise. Last season, there were quite a few. In most seasons, like this one, there are zero to extremely few.

This again suggests to me that it’s not always the same group of whales visiting Vava’u.

Male humpback whale swimming past at high speed,
fending off challengers for the female (dark whale visible lower left background)

Lots of singers; bass not so bass: There seemed to be a relative abundance of singers this season. This probably makes sense, given the apparent abundance of whales overall. Somewhat unexpected, however, was the number of singers we came across toward the end of the season.

I generally expect there to be more singers early in the season, because I believe that singing is part of the interaction/ communication/ competition among males in association with social status and securing the right to mate.

Early in the season, there should be more females around, so I’d expect competition to be high. Toward the end of the season, there should be relatively few whales remaining (including eligible females), so logically, there should be less competition among males.

This year, however, half of the 14 singer encounters we logged took place between 14 and 22 September, pretty late in the season…so once again, the whales defied my efforts to make sense of their behaviour.

Also worth noting, the bass in the song this season wasn’t quite as deep and booming as I’ve experienced in the past. Even while hanging a couple of metres directly above singers on multiple occasions, I didn’t feel the same “oomph” that usually characterises the low notes in humpback whale song.

Crystal Ball Gazing (Sort of)
Last year, I felt reasonably confident about setting out a case for a baby boom this season, because the deck seemed to be stacked that way. There were babies around, but not a record number by any means, and we came across a lot of behaviour associated with reproduction.

This year, there were heaps of whales and lots of babies. It seemed like there was a reasonable level of mating-associated activity….heat runs, courting pairs and such…but not quite as much as in 2010.

So what do I think is going to happen next season?

To be honest…I have no clue.

With so many babies born this year, probability should favour fewer, rather than more, little ones next season.

But…no one really knows how the greater population of southern humpbacks decides where to go. Judging by the ever-changing number of white-pec whales and individuals with split dorsal fins, for instance, I don’t believe that the same whales visit Tonga each season. I think it’s more likely that individual whales cycle around various areas, which could explain why we more often see readily ID-able individuals every couple/ few years, rather than in consecutive seasons.

As such, there is certainly some chance that a significant proportion of female whales that have mated elsewhere this year will, for some reason, again converge in Tonga, resulting in another baby boom. From memory, there were lots of babies in the consecutive seasons of 2004 and 2005, for instance.

On the other hand, there were relatively few babies in 2008, moderate numbers in 2006, 2007, 2010, and very high numbers in 2009 and 2011.

So basically…there’s no obvious pattern. There are without doubt a host of variables at play, most of which we probably don’t know about, much less understand.

If I had to make a guess though, I’d wager the chances of another 40+ baby year are relatively low, and we’ll end up with a count in the 20s. In other words…a reversion to the mean.

While I’m taking a stab in the dark, I’ll go out on a limb and predict substantially better visibility, on the theory that the particles in the water are the result of prolonged rains and warm weather due to the El Niño/ La Niña cycle.

Time will tell if gut instinct is pointing me in the right direction, or if the whales, weather and water outsmart me.

One of my best friends in Tonga

Wrap-Up
I’d like to wrap up my final long-form blog post for the 2011 humpback whale season with a really big “Thank You!”

Even though I’m doing all the work of keeping track of whales, cataloging photos, recording GPS data, taking notes and producing the summary file, a lot of people have contributed to the calf sighting and ID process…some of whom I’ve named in my periodic updates this season, most of whom I have not.

Some people have contributed photos and sighting data; others have contributed knowledge and experience, responding to my numerous emails and other messages that start with: “Do you happen to know…?”.

I’m particularly grateful for the trust and friendship of everyone who has travelled to Tonga with me, not just this season, but in past years as well. Besides having lots of fun, you have made it possible for me to spend the time to collect and collate my annual calf count data.

During and after each season, I spend hundreds of hours going through the data collected, organising it, and parsing it into easily understandable format. Then I put together a summary file and Google Maps, which I post to the internet…so that anyone who is interested can see the results. (I’m getting to work on the 2011 file now!)

In short, your generosity and support have allowed me to crowd-fund this research effort.

So to sign off for now…to all the people who have joined me this season and in the past, from the United States, Japan, Singapore, Taiwan, China, Thailand, Hong Kong, Korea, Sweden, Russia and Canada…Thank you, 有り難うございました, 谢谢, ขอบคุณครับ, 감사합니다, tack, Спасибо, and for the Canadians…Thank you, eh.

I’ll post my 2011 summary file as soon as I can (with 45+ babies to work through, it’s going to take a while!), and also my Tonga trip schedule for 2012.

If you’d like to consider travelling to Tonga with me next season, please drop me a short note via my contact form.

Previous Posts from the 2011 Humpback Season in Tonga:
Swimming with Humpback Whales in Tonga | 2011 Season Part 1
Swimming with Humpback Whales in Tonga | 2011 Season Part 2
Swimming with Humpback Whales in Tonga | 2011 Season Part 3
Swimming with Humpback Whales in Tonga | 2011 Season Part 4
Swimming with Humpback Whales in Tonga | 2011 Season Part 5
Swimming with Humpback Whales in Tonga | 2011 Season Part 6
Swimming with Humpback Whales in Tonga | 2011 Season Part 7

Previous Calf Count Summary Files and Maps:
Humpback Whale Calf Count, 2009
Humpback Whale Calf Count, 2010

A treat of delicious homemade gelato
from my friends Franco and ‘Ofa to bid us farewell

It’s been another eventful and educational week.

My calf count is up to 44 ID-ed mother/ calf pairs now (with several uncertain pairs to which I may be able to assign IDs after more careful review).

The new calf IDs this week comprised:
- Fataha (#41), accompanied by an escort;
- Faua (#42, male), the second calf with all-white pectoral fins that we’ve photographed this season. Mom also had all-white pectoral fins. This pair were also in the company of an escort;
- Fatolu (#43, female), ID contributed by my friend Douglas Seifert (who has been here with his lovely wife Emily for the past couple of weeks and has been kind enough to contribute valuable calf-sighting information and photographs…thank you!). No escort with this pair;
- Fafa (#44, female), another injured calf with wounds similar to those of Tahafa (#14, male). No accompanying escort.

Faua (#42, male), the second humpback whale calf with all-white
pectoral fins this season. Mommy also has white pectoral fins.

Resightings included:
- Uatolu (#23, female), which I originally ID-ed at Toku Island on 02 September, and Douglas Seifert photographed in Vava’u on 20 September (19-day interval). This is the second example we have documented this season of a mother and calf travelling between the two locations;
- Uanoa (#20, male), accompanied by an escort. We originally ID-ed this calf on 29 August. I subsequently received a photo of this calf from Kristy Peacock, a guest at Mounu Island Resort, taken on 24 August. I photographed this calf again on 24 September (an interval of 32 days from first documented sighting) and was able to determine that the calf is male;
- Tahafa (#14, male), our ninth(!) encounter with this injured calf. We have now documented this calf going from Vava’u to Toku then back to Vava’u, between 23 August to 24 September, a span of 33 days. For a detailed timeline of the first eight encounters, please see Part 6.

Overall, it seems that there are still many whales in the area, including mother/ calf pairs. We have, however, ID-ed fewer new calfs this past week than in previous equivalent periods. This could be due to chance, but I have a feeling that the lower tally may reflect the fact that we’re approaching the tail-end of the season, with an accompanying decrease in the number of births.

One other observation: It may just be my imagination, but there seems to have been a proliferation of singers in recent days. Maybe we’re just noticing more, or perhaps there are actually more whales singing now.

I’d always assumed that the prevalence of singing would be greater during the early part of the season rather than the latter, but maybe I was mistaken. In the past 10 days, we’ve come across 10 singers, and on Wednesday, we came across one of the most complacent and cooperative singers I’ve ever encountered.

Humpback whale calf Uatolu (#23, female), the second calf I’ve documented travelling
between island groups, thanks to help from Douglas Seifert

Tahafa Back in Vava’u
The big story this week revolves around injured baby humpbacks.

First, there was Tahafa, the injured male calf that I’ve written about extensively in previous posts.

Humpback whale calf Tahafa (#14)
with mom resting in a head-down position

Tahafa has, without a doubt, shaped up to be the star of the season. Over 33 days and through nine encounters, we’ve watched as this little calf has developed from a wee little tyke suffering from grievous bodily harm (see Part 3 for photos) into a happy, healthy young lad full of energy and confidence.

This alone would be amazing enough, but we’ve also now tracked this baby from Vava’u to Toku (accompanied by a long-term escort that mommy seemed to take a shining to) and back to Vava’u again. On 24 September, we again came across mom and baby, this time playing in the inner waterways of Vava’u. We had last seen the pair on 16 September in Toku, some 40km away.

As with our last sighting, mother and baby were not accompanied by the escort that kept them company for at least 14 days (1 to 14 September), suggesting that the parting of the ways I documented as taking place between 14 and 16 September was a permanent separation. (Refer to Part 6 for more details).

The good news is that Tahafa’s injuries seem not to have led to any serious long-term damage. Over the past month or so, the calf’s wounds have healed well:

Tahafa’s wounds are generally healing well

In our recent encounters, the young humpback has been extraordinarily playful…tail-slapping, breaching, flopping around…doing all the fun things that baby humpbacks do as they explore their surroundings:

Overcast skies didn’t stop Tahafa from enjoying himself

Happy, healthy humpback whale calf Tahafa playing near the surface

At this stage, I’m confident that Tahafa will make it through the season and head south with his mother.

He’s not completely clear of the woods though. The large chunk taken out of the anterior portion of his dorsal fin hasn’t entirely healed over. It looks as if some flesh is still exposed; viewed from the side, the base of Tahafa’s dorsal fin seems to have some tearing.

If you compare the photos below to the image I posted in Part 3 though, you’ll see that the wound appears much better than before, so at least there has been visible healing progress.

Tahafa’s wounds are mostly healed, except his dorsal fin,
which still has areas of exposed flesh

There has been some discussion/ speculation about what may have been responsible for these wounds, with theories spanning tiger shark attack, run-in with a boat, and ambush by a group of marine mammals.

Bear with me for a little longer, and I think I can set out a strong case for marine mammal attack, based on a series of images showing similar wounds on three other baby humpback whales I’ve ID-ed this season, and also upon information/ input from a couple of fellow photographers.

The Case for Marine Mammal Attack
Let’s start with the latest calf I’ve ID-ed, a female named Fafa (#44), which we came across on 22 September. Fafa and mother were not accompanied by an escort.

Though not quite as extensive as Tahafa’s wounds, Fafa’s injuries were apparent from the moment I saw her.

This calf was covered with small circular and semi-circular wounds, identical to those on Tahafa. Also like Tahafa, Fafa had multiple wounds distributed all over her body, as opposed to a single wound or wounds concentrated in one place.

Humpback whale calf Fafa (#44, female) re-entering the water after breaching.
Note the wounds all over her body.

Particularly egregious was an injury to the calf’s fluke, with a chunk taken out, resulting in a tear to her right fluke:

Large chunk missing from humpback whale calf Fafa’s (#44, female) fluke

Upon closer inspection of underwater photographs, there are marks that look like an impression left by a bite mark, sort of like what happens when you go to the dentist and he/ she takes an impression of your teeth. The bite marks are all small, suggestive of a relatively small mouth:

These marks on Fafa’s mouth look to be impressions left by
the upper and lower jaw of whatever animal attacked this calf

Fortunately, Fafa seemed unfazed by whatever trauma had befallen her, as the calf was playful and brimming with positive energy.

My encounter with Fafa got me thinking about another calf I had seen much earlier this season, Fitu (calf #7, photographed on 18 August).

I posted a picture of Fitu back in Part 2, when I noted the unusual clover-like marking on the calf’s back, magnified in the graphic below. Given the wounds I’ve since seen on Tahafa and Fafa, my belief now is that this clover-like pattern is also the result of attempted bites by a similarly sized mouth.

These marks on Fitu’s (calf #7) dorsal surface
look like unsuccessful bite marks

In addition, upon closer inspection of photographs of Fitu, I noticed what appears to be a dental impression on Fitu’s left pectoral fin, again perhaps the result of an attempted bite:

Possible bite impression on left pectoral fin of Fitu (calf #7)

While I was grappling with these data points, we had another re-sighting on 24 September, this time of Uanoa (calf #20, male), with mom and escort.

Uanoa’s mom has a prominent white patch on both flanks, which makes her relatively easy to recognise. The water was murky, skies overcast, and whales on-the-go when we came across them, so I only had one drop to take a look and get photos.

From mom’s white patch, and more importantly…the missing tip of the calf’s left pectoral fin, I was almost certain it was Uanoa, a hunch I was able to confirm later that evening after I downloaded images.

Uanoa (#20, male) is missing the tip of his
left pectoral fin, possibly from a bite

In isolation, the missing tip of the calf’s left pectoral fin might not mean much. But taken together with the wounds and markings on Tahafa, Fafa, and Fitu…I’d say there’s a reasonably high chance that the same type of culprit is behind all of these injuries.

Earlier in the week, Mark Strickland contacted me to suggest that Pseudorca crassidens, commonly known as false killer whales, might be more likely candidates for coordinated attacks on humpback whale calfs than pilot whales (I had previously suggested pilot whales as possible perpetrators).

Mark had an incredible encounter with these marine predators some years ago in Thailand, when he came across a bunch of them hunting sailfish.

To cut to the chase, Mark saw these pack hunters in action, chasing down and obliterating the large fish. A person in the water was stabbed through the leg and abdomen by the fleeing prey and had to be taken to the hospital for emergency treatment of a perforated colon. Fortunately, she made it through OK.

Anyway, given Mark’s direct experience with false killers (and my lack of such experience with them), I took his feedback seriously.

I then asked another friend, Douglas Seifert, for his thoughts, and he mentioned that false killer whale attacks are generally characterised by “raking” marks on their victims. Sure enough, upon close inspection, both Tahafa’s and Fafa’s bodies exhibited such marks.

Example of raking marks on injured calf Tahafa’s pectoral fin

Douglas also passed me copies of some peer-reviewed papers about Pseudorca, one of which made reference to another paper that documented false killer whales attacking and killing a humpback whale calf in Hawaii (Hoyt, E. 1983. Great winged whales, combat and courtship rites among humpbacks, the ocean-not-so-gentle giants. Equinox 10:23-47).

So…while it’s difficult to be 100% certain without witnessing an actual attack myself…I believe that the photographs of four injured calfs from this season (Tahafa, Fafa, Fitu, Uanoa), along with the feedback/ input from Mark and Douglas, make the case for a marine mammal attack (probably false killer whales) about as watertight as you can get.

This year certainly isn’t the first time I’ve seen injuries like this on humpback whale babies here, but it’s the first time I’ve had a critical number of well-documented/ photographed subjects to study, augmented by the advice and guidance of two knowledgeable friends.

Sing Me A Song
To round out the week’s experiences, we came across one of the most cooperative singers I’ve ever encountered. Perhaps, in fact, the most cooperative.

In reasonably calm water (with bad visibility unfortunately), this singer adopted the classic head-down pose and remained stationary with fluke at around 10-15 metres for 10-15 minutes at a times. When he came up, the whale didn’t move far, and when he went down again, he stayed shallow.

Most of all, the singer didn’t seem to mind our presence, even though it was clear that he was aware of the pesky little humans hanging around, listening to his solo performance.

One of the most cooperative singers I’ve ever come across,
in the classic head-down posture

One thing I’ve noticed is that the bass of this year’s song isn’t quite a “booming” as in previous seasons. Even when I hovered directly above this singer, the low notes didn’t reverberate through me quite as strongly as I’m accustomed to.

This has been the case with all the other singers we’ve encountered this year (14 to date), so I assume it’s a characteristic of this season’s tune.

What a week.

Since my last update, we’ve hit 40 ID-ed humpback whale calfs(!!!); re-sighted several babies we previously ID-ed; visited Toku again; been in the midst of a power-packed 8-whale heat run; come across humpbacks with split dorsal fins for the first time this season; been buzzed by a bunch of adorable baby reef sharks; swum among pilot whales; and even had a large pod of spinner dolphins accompany the boat for a good half hour or more.

The weather has finally been cooperative, so we had sunshine, clear skies and calm winds for the entire week. But…the low visibility that’s prevailed for the entire season actually worsened. It seems like there was some sort of mass spawning event around the recent full moon, which basically mucked the water up even more than it already was. Just perfect for underwater photography. Sigh.

Toluono (calf #36, male) relaxing at the surface

Calf Count
With 40 baby humpback whales ID-ed and counting, we are totally off the chart. I still have nearly two weeks left here, so I’m almost certain the total count will increase.

But by this point in the season, the number of newborns should begin to diminish. In a “normal” season (to the extent such a concept exists), I’d expect that we’d be approaching the tail-end of the birth bell curve, and that from this point forward, the balance of our calf encounters might begin to shift to a greater number of re-sightings, as opposed to new IDs.

This season, however, has proven to be mind-boggling in many respects, so it’s entirely possible that the birth bell curve stretches out for a while more.

In an average season, I’d expect the earliest sightings of newborn humpbacks to occur some time in July, with the latest being in October. This season, the earliest sightings were in late June, i.e., early.

It will be interesting to see if new calf sightings tail off sooner than expected, or if there is no “forward shift”, so to speak, of baby humpback births.

We ended the week with 40 ID-ed humpback whale calfs.
(black = 2008; blue = 2009; red = 2010).
Extracted from my 2010 humpback calf summary.

Also this week, I had my first “calm” encounters with mother/ calf pairs. For most of the season, females with babies have been “neutral” to “skittish”, meaning there have been some, but relatively few, encounters during which mommy humpbacks remained stationary and let their babies swim and play at the surface.

I finally had two such encounters this past week, although only one of the two was truly relaxed…little baby girl Tolunima (calf #35) and her mom.

In the other encounter…with Toluono (calf #36, male)…cow and calf were swimming, but when we entered the water for the first time, the mother skidded to a complete stop and rested at shallow depth, letting the calf explore its surroundings and us…before she arose from her afternoon snooze and continued on her high-pace trek southward.

Finally, we had three re-sightings this week:

- Seventh and eighth sightings of Tahafa (calf #14, male), more about this calf below;
- Second encounter with Tolutaha (calf #31, female);
- Second encounter with Tolufa (calf #34, male).

Tolunima (calf #35, female). This is the first mother/ calf pair I encountered
this season that was stationary while calf played above.

The Little Calf That Could
The star baby of the season has turned out to be Tahafa, the 14th calf we ID-ed. Since my first encounter on 22 August, we’ve come across this little boy whale eight times:

1. 22 August: First encounter, a day after hearing reports of an injured calf, reportedly attacked by a large tiger shark. As soon as I saw the calf, I realised that the stories of a large shark were inaccurate. There was no way the wounds were caused by a tiger or similar animal. The wounds were small, distributed all over the calf’s body, and for the most part shallow. Mother and baby were not particularly friendly, but the baby looked completely healthy.

2. 1 September: Shawn came across this mom and calf, and reported that they were calm and relaxed, a major change since our first sighting, which was a cause for anxiety. There was an escort present. He noted: “Baby seemed feeble and might require extra care. Lacking the spring/ charisma of most calfs. Seemed like the mom had to nose the baby up at the surface. Seemed like the escort understood this and was super respectful of the mom and calf. Sitting below until they came up. Initially, didn’t even know the escort was there.”

3. 2 September: Much to our relief, the baby looked healthy this time, and was quite playful, breaching on several occasions. Still with escort.

4. 3 September: Baby was again playful. Lots of remoras on the baby. Still with escort.

5. 7 September: Mom, baby, escort travelling. Escort breached and tail-slapped. Baby flopped and twirled at surface.

6. 9 September: Still with escort. Baby looking good.

7. 14 September: Found Tahafa with mom and same escort at Toku. Escort fought off multiple male challengers, up to five at a time. Mom and baby relaxed, both very friendly to swimmers. Baby extremely playful and inquisitive. Finally able to determine that Tahafa is male.

At one point in this extended encounter, one of the male whales was singing while swimming. I believe it was the escort, as it was directly beneath me in shallow water, and the sound literally “boomed” through me as I swam. This is not the first time I’ve been in the water when one of several male whales has been singing in an active competitive situation centering upon a mother/ calf pair. It’s not even the first time this season. I’m sure there is something to this. Perhaps it’s a dominance behaviour, intended as a warning to the primary escort’s would-be challengers?

8. 16 September: Sighted Tahafa again at Toku. This time, the escort was gone. We did not attempt to get into the water. Decided to leave mom/ baby alone.

Injured calf Tahafa together with his mother. The baby’s wounds have healed nicely.

So over a 26-day period, we’ve documented this injured baby eight times, witnessing the baby’s recovery from wounds due to some sort of traumatic encounter. We’ll probably never know exactly what happened, but one thing is for sure…there was no tiger shark involved.

My preferred guess is an assault by a group of marine mammals (such as pilot whales). Another possible explanation is a run-in with some sort of motorised craft.

In any event, the baby has fully recovered, and the wounds are for the most part healed. In our most recent encounters, Tahafa was unmistakably healthy, energetic and inquisitive…just like a baby whale should be. Hurray!

If we do come across Tahafa again in future seasons, it’ll be easy to ID him from the wounds, especially the missing anterior portion of his dorsal fin.

Escort Enigma
Watching Tahafa’s healing/ recovery process has been fascinating and rewarding, but there’s more to this story…

To start, Tahafa is the first calf that I’ve documented in both Vava’u and Toku, which are about 40km apart. Mom + injured baby (together with escort) swam many kilometres through open ocean, in areas I know are frequented by pack hunters like pilot whales.

This underscores my observation over previous seasons that Vava’u does not seem to be a place where whales stay with their babies.

They may give birth here and/ or visit for some duration. They may even return during a given season, but for the most part, Vava’u is a way station for them, not a permanent home for the season.

Recall also that both the mother and the calf seemed to become relatively calm and relaxed after the escort joined them, sometime between 22 August and 1 September. It’s certainly not the first example I’ve seen of an escort having a soothing effect on mom and baby, but it’s notable in this instance because of the extended period of association.

This is Toluhiva (calf #39, female). Here, the calf is nuzzling the escort,
demonstrating that escort whales can be on good terms with babies

Specifically, the same escort accompanied this mom and calf from at least 1 September to 14 September, over two weeks. Admittedly, I haven’t been meticulous about recording observations pertaining to escort behaviour prior to this season, but this one example illustrates that escorts can and do stay with mother/ calf pairs for extended periods of time.

At this juncture, I have no idea if this particular escort’s behaviour represents the norm here, or if this is an outlying case. But documenting this extended association has given me cause to wonder why escorts even bother accompanying females that already have babies.

The desire to mate would be a logical assumption, one that I’ve taken for granted to date.

But here’s the thing…if moms that show up in Vava’u do regularly mate with escorts (and many moms here seem to be accompanied by escorts), does that imply that those moms have babies in consecutive years?

Consider this possibility for a moment: If a mom mates while she still has a newborn, that would mean that she’d be pregnant while raising that newborn, and would essentially have to face the daunting task of raising a baby while incubating a new baby over the same 12-month period or so.

Then she’d have to return from the south next winter with yearling in tow, part ways with her baby from this season, and then have the next baby soon thereafter…possibly having to go through the whole ordeal again if she’s approached by yet another eager-beaver suitor(s).

I have previously collected data here (Mother of Chibi-chan 200816 same as mother of Floppy 200929; Mother of Scratches 200801 same as mother of Stitches 200904) to suggest that this scenario might be possible (and have also heard from friends in both Hawaii and Japan that there are similar examples there), but you know…it seems like a major undertaking for a female humpback, something that any sane female just wouldn’t want to do…and might not survive if she did.

So even though such behaviour appears to be possible, it seems a stretch to assume that it would be the standard scenario. The energy requirements to feed and raise a newborn + incubate another calf at the same time would be humongous.

Here is an excerpt from a paper that Karen was kind enough to forward to me that addresses this specific issue:

Escorts to mother/ calf pairs on the breeding grounds are invariably male (Glockner-Ferrari & Ferrari, 1985; Medrano et al., 1994), and it has been suggested by Darling, Gibson & Silber (1983) that escorts associate with lactating females in the hope of mating them if they come into post-partum oestrus. However, the high cost of lactation (Lockyer, 1987) makes it likely that a female who is simultaneously pregnant and lactating will be in poorer body condition during the year in which she is nursing the subsequent calf. The percentage of females that we have observed (Clapham & Mayo, 1990) with consecutive-year calves in the Gulf of Maine (a feeding area) was significantly lower than that recorded by Glockner-Ferrari & Ferrari (1985) from the Hawaiian breeding grounds. If this is not entirely due to a bias in sampling towards mothers off Hawaii, the difference may at least partly reflect higher mortality among second calves (those born after an interval of 1 year) prior to arrival in high latitudes. If this is indeed the case, then escorting a mother/ calf pair on the breeding grounds may be a strategy that is inferior to courting or competing for a female who is not currently incurring the expense of lactation.

- Clapham, Phillip J. (1996) The social and reproductive biology of Humpback Whales: an ecological perspective, Mammal Review, 26, 38

This is the escort whale that accompanied Tahafa (calf #14) for at least two weeks

To translate…the paper suggests that for a male humpback to mate with a cow that already has a calf might result in lower probability of his offspring’s survival, and thus not be a wise strategy. This intuitively makes sense.

But if this isn’t the normal situation, then why are so many mother/ calf pairs in Vava’u accompanied by escorts?

So far this season, 20 out of 40 (50%) females with babies we’ve ID-ed have been accompanied by at least one escort. In addition, 11 out of 27 (41%) mother/ calf pair sightings for which we have not established in ID have also involved at least one escort.

One possibility is that the presence of an escort somehow makes it easier for us to approach and ID mother/ calf pairs. I don’t ascribe a high probability to this, however, as the presence of an escort often makes it more difficult to approach females with babies, as I outlined in an earlier post.

Plus, even though I haven’t been tracking escorts in an organised manner during previous seasons, I know from experience that the association of escorts with a significant ratio of females with babies here has always been the case, at least for as long as I’ve been visiting Vava’u.

Of interest, the same paper, on page 40, suggests that the frequency with which males choose to associate with mother/ calf pairs may vary from location to location:

It is curious that, while lactating females are often at the centre of competitive groups in Hawaiian waters (Baker & Herman, 1984b; Glockner-Ferrari & Ferrari, 1990), their occurrence in such groups in the West Indies is far less frequent (Clapham et al., 1992). The absence of calves from most competitive groups in the latter region may reflect a preference by males for females who are not lactating (and are therefore in superior condition). However, why such a phenomenon should apparently not also be observed elsewhere is difficult to understand unless the frequency of post-partum oestrus differs between populations.

Taking this information at face value, it seems like the tendency of males to associate with mother/ calf pairs here resembles the behavioural patterns of humpback populations that visit Hawaii more than of those that frequent the West Indies.

Tahafa’s long-term escort. Scraped up dorsal fin…evidence of battle

A Few More Questions, Some Speculation
As I pondered the details of our multiple encounters with Tahafa, mom and escort, a few more issues came to mind.

Why are some escorts (like Tahafa’s) seemingly so loyal (spending at least 14 days by Tahafa’s and mother’s side, including crossing 40km of open ocean and doing battle with five or more aggressive males at a time on multiple occasions) and prepared to undertake bodily risk? (In one particularly spectacular conflict, I watched the primary escort ram nose-first into the belly of another male.)

Another head-scratcher…why, after spending so long with Tahafa and mom, did the escort suddenly disappear by 16 September, less than 48 hours after I had watched the escort engage in serious combat seemingly for the purpose of defending his access to Tahafa’s mom?

And one final twist…when we spotted Tahafa and mom on 16 September, there were dozens of hormone-raged males in the immediate vicinity (like right next to Tahafa and mom), including several that were in hot pursuit of other mother/ calf pairs, and at least seven that were body-slamming one another over bragging rights to what appeared to be a single female.

The question that pops to mind is…if Tahafa’s mom merited so much attention on 14 September (“territorial” aggression by the primary escort + challenges by many other males), then why, less than 48 hours later, was Tahafa’s mom essentially ignored by all the horny males in the area?

I certainly don’t have any definitive answers to these cetacean conundrums, but I’ve pieced together what might be a plausible narrative, one that I can maybe use as an initial framework for developing a better understanding of mother, calf, escort interactions here in the future. It’s pure speculation, trying to fit all the pieces together, but here goes:

What if female humpbacks (whether they are with calf or not) are able to advertise their reproductive status? So let’s say some females with babies go into oestrus while they’re around Vava’u, and they somehow communicate their reproductive readiness to the males in the area (pheromones? audio signals?).

Healthy, happy Tahafa (calf #14) with mom,
primary escort visible in background

Let’s say this takes place some time before she’s actually ready to mate, perhaps up to two weeks.

If Tahafa’s mom sent out just such a signal, and the escort (along with other males) picked up on it back in late August, then there may have been a contest for her acceptance, resulting in the presence of a primary escort with Tahafa’s mom by 1 September (the first time we noted the presence of the primary escort).

From that period forward, the primary may have fended off dozens of challengers, as the female continued to advertise her fertile status.

In this specific example, Tahafa’s mom (and Tahafa for that matter) seemed pleased/ comfortable with the primary escort, so she may not have actively sought to “accept” a different escort, or perhaps she did, but always ended up choosing to associate with the primary escort. In either case, the same primary escort prevailed.

The challenges may have culminated in the all-out assault of multiple males that we witnessed on 14 September, when the primary escort was challenged from left, right, above, below…basically everywhere…by two, three, sometimes five whales at a time, and not always the same whales, meaning the total number of challengers exceeded five.

The reason for the culmination may have been that the time for Tahafa’s mom to mate was near (full moon was two days earlier, on 12 September), and the challengers sensed an opportunity to usurp the primary escort. They could invest a little bit of time and possibly gain the right to mate. If they failed, they wouldn’t have invested too much time, and could quickly move on to something else.

By 16 September, mating was finished. Perhaps the primary escort successfully defended against all challengers and mated.

After that, the primary escort…being male, saw no reason to stick around and left. Other males, sensing no reason to court Tahafa’s mom, diverted their attention to the other receptive females in the area (several with babies, one without).

Tahafa and mom were left in peace…for the first time in several weeks…explaining why the pair were left alone even as wild heat runs and competitive groups coalesced all around them.

Whatever the case, Tahafa, his mom, and the primary escort that accompanied the pair have given me a reason to pay more attention to escorts in future seasons.

If you happen to have any insight into how plausible or not the speculative scenario above might be, please let me know!

Surrounded by humpback whales in a massive, high-energy heat run

Toku Revolutions
Besides the encounters with Tahafa described above, we also had a massive 8-whale heat run at Toku, one that literally took us in circles…around and around and around…as the whales snorted, slapped, smacked, lunged, and dived at high speed.

I’ve seen a lot of heat runs over the years, but this one ranked in the top five or so in terms of energy levels. My friends from the People’s Republic of China who were with me this week couldn’t get enough. Lots of hoots, howls and woohoos! all around.

I also photographed two whales with split dorsal fins there. This is such an unusual trait that I’ve been keeping track of humpbacks I see with dorsals like this, figuring that it’ll be relatively easy to recognise them in the future.

I hadn’t seen any all season (in contrast to five or so I photographed in 2010). Then on 16 September, I photographed two such whales, at the same place, at nearly at the same time. One was the mother of Fanoa (calf #40), and the second was one of the males involved in the big heat run.

One of the whales in the heat run had a split dorsal fin

And just to round out the week, I had a brief visit with a handful of cute baby reef sharks that came to check us out:

One of several baby reef sharks that buzzed us

And then some pilot whales, with a wee little one among them:

Pilot whales in the blue

In case you couldn’t tell, I’m running out of steam and can’t write much more.

My friends from China leave tomorrow, following which, I have several groups arriving from Japan…so I need to catch up on some sleep and recover from the week’s activities.

It’s overcast with a bit of rain today, but I certainly hope the great weather we had last week comes back.

Friends from China, overjoyed with their whale encounters

The past week has been characterised by an oxymoron: frustrating awesomeness (I know, “awesomeness” isn’t a word, but it gets the point across).

First, the frustration. We started the week with a brief, but powerful windstorm at around 04:00 on Sunday night that literally blew stuff off our balconies and dislodged coconuts from their high perches. The maelstrom sounded like a typhoon, and I was concerned that we wouldn’t be able to go out.

By daylight though, things looked much better…relatively flat seas with little wind. Much relieved, we headed out in the morning, and even managed to find a mom/ calf pair (#29 of the season). But within minutes, the skies turned to grey, while the winds shifted direction and picked up to 20+ knots. Four+ metres swells kicked in just for our added pleasure.

Aiyah.

The next day, we found a demonic mother/ calf pair (Unknown #17) early in the morning. The pair popped up for a quick breath, dived down, swam for 100-150m in a random direction, then repeated this cycle. They led us on a wild-whale-chase, until we gave up and moved on, unable to establish an ID. A couple of other boats also wasted invested time in this pair, but no one managed to get a good look.

After that, we found a singer. Just as I got everyone into the water, it stopped singing and left. How rude.

Then, we found another mother/ calf pair at the bottom end of Hunga channel, which was only marginally more cooperative than the demonic duo. I managed to get a reasonably good look, but no one else did, as the pair moved too quickly. It turned out to be whales I knew already but haven’t assigned an official ID to yet, Unknown calf #10 and mom.

And finally…Thursday was just a wipe-out day. Total, utter nothingness…unless you happen to be fond of clouds, rain and bad visibility.

Courting humpback whales: the white one in front is the male,
the whale spyhopping in the background is the female.

But (and this is a big but), these periods of despair were more than offset by some amazing encounters, including:

(a) The best calf interaction I’ve had the entire season, with a baby humpback that turned out to be #32, Toluua. This ID broke our record of 31 pairs ID-ed in 2009, and…to make this encounter even more rewarding and poetic, the mother was the same female as the mom of calf #13 in 2009, Luna. I recognised the adult on sight, and of greater significance, I knew her “personality” (more about this below);

(b) A power-packed, testosterone-laden 8-whale heat run (woohoo!);

(c) Two pairs of courting male/ female humpback whales (power, grace and beauty);

(d) Re-sightings of several mother/ calf pairs previously ID-ed this season;

(e) A bunch of other stuff: two hammerhead sharks at the surface (one small, one large), two sea snakes (one of which had a little fish swimming with it, the other of which had Dan swimming after it…Dan’s comment “Snakes feel good; wet snakes feel better.”); a female crab swimming in mid-water carrying a large clutch of nearly ripe eggs that we initially mistook for a turtle; one actual sea turtle that had the good sense to dive before we got into the water; birds dive-bombing and snagging flying fish; pilot whales (one of my boats with Japanese friends on it); and a lot of breaching and other humpback whale surface activity.

It’s a New Record!
We actually ended this week with 34 humpback whale mother/ calf pairs ID-ed, but the one that really mattered for me was Toluua (#32) a little female calf (actually, she was quite big, indicating that she was born relatively early in the season).

Back in August (see Part 2), I set a goal of identifying at least 32 mother/ calf pairs this season. I had set out a case for a possible banner baby boom this season at the end of the 2010 season, and I saw evidence early on that the pace of calf sightings was consistent with a record-breaking tempo.

We’ve broken the humpback whale calf count record!
(black = 2008; blue = 2009; red = 2010)
Extracted from my 2010 humpback calf summary.

On Friday, 9 September, I was able to identify #32! (subject, of course, to going through all the photos and data more carefully after I get back home).

Reaching this benchmark was satisfying enough, but the actual encounter made the moment even more fulfilling.

First, I recognised the mother on sight. She was the mother of Luna, calf #13 in 2009, and is easily identifiable by her unique dorsal fin…sort of a stubby shape with white rune-like markings on it. I recall meeting this female for the first time in 2009, when I remarked: “If I ever see this one again, I’ll know it right away”, and sure enough, when I saw her dorsal fin on Friday, there was no mistake.

Even better…I remembered that she was very approachable. During several encounters two years ago, this female never swam away, never veered, never gave any indication she was troubled by the presence of boat or people.

With this in mind, I swam right to her when I got into the water, and sure enough, she swam directly toward me without hesitation. That left no doubt in my mind that it was the same whale.

I’m sure many biologists would frown upon ascribing a specific “personality” to a non-human animal, but in the two cases where I’ve immediately recognised an adult female humpback whale in different seasons, their dispositions have been the same (beside the mother of Luna/ 200913 and Toluua/ 201132, also the mother of Scratches/ 200801 and Stitches/ 200904).

To put it more bluntly, I was reasonably confident that Toluua’s mom would be comfortable with me right away, because she was comfortable in each encounter two seasons ago. Really comfortable.

Even more interesting, both of her babies, Luna and Toluua (both little girls), were also friendly to people, each demonstrating keen interest in swimmers, and approaching proactively.

Humpback whale calf Toluua playing, with mom and escort below

Here’s the thing…for most visitors to Tonga, who may, if they’re lucky, only meet a few mother/ calf pairs while they’re here, it’s impossible to notice possible traits like consistent personality of a single whale.

Say someone travels here for a couple of weeks and comes across 10 mother/ calf pairs. Two seem friendly, five seem neutral and three speed away at the mere suggestion of humans.

It’s easy in such a scenario to make observations such as: “That boat harassed those whales, and that’s why they sped away.”, or “We knew exactly what we were doing, and that’s why we were more successful than you.”, etc.

I’ve heard definitive statements of this nature asserted by tourists, boat operators, NGO representatives, and researchers many, many times over the years, and I’m certainly not immune from having similar sentiments at times.

But…what I’ve come to believe after spending so much time in the water with these animals here, perhaps more than any other person ever has, is that individual whales have unique dispositions/ temperaments (with the caveat that immediate circumstances, such as the presence of an unwanted escort, can of course affect behaviour).

So Luna’s/ Toluua’s mom behaved in the same manner in 2009 and 2011, just as Stitches’/ Scratches’ mom behaved in the same manner in 2008 and 2009.

And while we humans most probably can and do affect the whales’ behaviour, individual whale “personality” is an important factor, one that cannot be dismissed as nonexistent, irrelevant, or imaginary.

Bottom line…just because people haven’t spent enough time getting to know humpback whales in their element doesn’t mean we are justified in ignoring their unique personalities, or in drawing conclusions/ making definitive statements/ creating policy based primarily upon human standards, prejudices and most of all…ignorance.

It’s difficult for me to prove beyond doubt that this observation would hold true for the population at large, but after having spent hundreds of hours observing humpback whales in the water here, it’s a view that I am confident about articulating and defending, especially now that I have two indisputable, multi-year examples.

Anyway, Toluua and mom played with us for a long time, with mom stopping on occasion to rest while Toluua frolicked with us less-talented swimmers. At one point, an escort joined the pair (making huge gulping motions down deep as he approached), but fortunately, the escort seemed as comfortable with us as mother and calf were.

What a wonderful way to reach my goal for this season.

Toluua (calf #32). Toluua’s mom is also the mother of Luna, calf #13 from 2009.

More Baby Talk
It’s terrific seeing so many baby whales. It’s vindication in many respects, but most of all, for the many “discussions” we had years ago with people here who felt there were only a handful of juveniles born/ raised around Vava’u each season.

Establishing a methodical, documented calf count has provided an objective measure, and has shown that our initial gut feel that there were dozens of babies in many seasons seems to be correct.

There is certainly more that we don’t know about these whales than we do, but every little bit of fact-based information helps.

Besides our new calf IDs this week, we also had several re-sightings:

(a) Second sighting of Unknown #10, originally spotted on 1 September, this sighting on 6 September, an interval of 5 days. I have some photos of this underwater, as well as topside images of the mom’s and calf’s dorsal. The underwater images aren’t great, so I’m not prepared to assign this one an ID yet, but at the end of the season, if nothing else matches, this is a strong candidate for an additional ID;

(b) Sixth sighting of Tahafa #14 (the injured calf), meaning this calf has been here for at least 17 days, spanning 23 August to 9 September. Of interest, mom and baby have been accompanied by the same escort since at least 1 September. I don’t recall documenting such a long female/ escort relationship before. Good news…the injured calf looks healthy, strong and playful…hurray!

Sixth sighting of injured calf Tahafa (calf #14)

(c) Second sighting of Tolunoa #30. This mother/ calf were first photographed on 4 August by a guest at Mounu (before I arrived in Tonga). I have copies of some of the photos taken at that time. We photographed the same mother/ calf pair on 5 September, an interval of 32 days. The calf is a female.

(d) Fourth sighting of Tolu #3, a little boy. We initially ID-ed this mother/ calf pair on 18 August. This sighting was on 9 September…an interval of 22 days. Of note, there was no escort with mom and baby this time. I discussed the effect of an escort upon Tolu’s mom in Part 2, under the “Sex Change” sub-section.

It’s great having so many calf IDs and re-sightings this year…but wow, it’s so much(!!!) work cataloguing all the information and keeping it straight.

More Awesomeness: Heat Run
It’s been a while since I’ve seen a heat run this season. The fact that it’s been quite windy for a while may have something to do with this, as the humpbacks have a tendency to take their heat runs somewhat offshore where we can’t go if the conditions are too rough.

On Friday (same day that we ID-ed Toluua #32), we came across a massive 8-whale heat run. That’s over 300 tonnes of animal charging through the water at high speed, snorting, grunting and splashing the entire time!

The whales were travelling at high speed and diving a lot, so we only managed a few looks in the water. I almost got all eight whales into one frame:

Heat run with eight whales. Travelling fast and diving deep.

I’m a heat-run addict, so every single heat run I see is as exciting as my first. Maybe I’m affected by the excess of humpback hormones in the water?!

Yet More Awesomeness: Couples Week
One of the most beautiful and awe-inspiring sights on the planet is the courtship of two humpback whales.

Over the years, I’ve been fortunate enough to witness the interaction of perhaps ten such pairs or so, and all I can say is that the whales’ combined grace, power and elegance defies description. Imagine the most intricate and refined of ballets, choreographed and performed by 40-tonne animals in the water, with every move executed to pinpoint precision.

On Tuesday (after our frustrations with the demonic duo mother/ calf, the non-singer singer, and Unknown calf #10), we came across a courting pair, just as we were about to throw in the towel and call it a day.

At a distance, we saw five whales together, so it’s quite possible that there were other whales with the pair before we reached them. But by the time we arrived on the scene, only the two were left, and from the moment we went into the water, they were as friendly and inquisitive as can be.

When the circumstances are right, courting pairs can often take an extraordinary interest in people, and even go so far as to “incorporate” swimmers into their elegant love-inspired rituals. I’ve swum on numerous occasions among the sinuous motions of two lovestruck whales, and have, after much experience, grown accustomed to their proactive swim-bys…when the whales turn around and head straight for me…an intimidating sight, but behaviour that I now know is not aggressive, but is intended to encourage me to keep up with them, even as I pant and heave for every breath.

We were in open water, far outside the main Hunga area, so the whales could have easily ditched us. Instead, they circled around and around, coming back every time we couldn’t keep up…behaviour typical of a friendly courting pair.

We swam non-stop for nearly an hour, so everyone spent lots of quality time with the amorous whales. It’s really amazing how long, hard and far people can swim when they’re making eye contact with humpbacks!

I consider myself fortunate if I come across one amicable courting pair a season, but on Saturday, we saw another, at Toku.

Courting pair (dark one female, white belly male) that was buzzed constantly
by two or three single males at Toku Island.

Toku Reloaded
Sean, Ray, Dan, Kozy and Nana started their adventure here with a trip to Toku, and we ended with a visit to Toku as well, on the final day of their stay in Vava’u.

Travelling the 40km or so to this small island requires relatively benign wind and ocean conditions, so it’s not an excursion that can be undertaken often. In fact, I had only visited once prior to this season. For one group to manage two visits to Toku in one trip is quite a stroke of luck!

Even better, it rained all day in Vava’u, while we had brilliant sunshine while we were at Toku.

It seemed like there were fewer whales overall around Toku this time, but we came upon a courting pair right away.

As is often the case with such pairs, the female demonstrated significant interest in us. The encounter wasn’t as rewarding as the previous pair, however, as two males (three at times), continually pursued this two lovebirds (lovewhales?), perhaps challenging the male.

As a result, the couple couldn’t focus on their courtship rituals and swam continually. The water was full of high-pitched squeaks, squeals and other calls, perhaps banter from the would-be challengers taunting the male in the pair. (Note: Humpback whales can be very talkative. Their well-known songs are just a small part of their vocal repertoire.)

We did manage to see the pair and the challengers up-close a few times though.

Toward the end of our final day at Toku, we came across a mother and calf (Tolutolu #33), accompanied first by two escorts, then three, then back to two, and finally one. While the female was swarmed by agitated males, she wasn’t terribly receptive to people in the water (go figure).

But when only one male was left, she relaxed, which allowed me to get a few photos for ID purposes.

Again, we witnessed first-hand the effect that escorts can have on female whale behaviour. It should perhaps come as no surprise that a mob of rowdy boys can make a respectable girl nervous, but it’s educational and rewarding nonetheless to see this up close.

Tolutolu (calf #33 of the 2011 season) with mom

I was land-bound for much of the past week (only went out on the water on Tuesday, Friday and Saturday), but it’s certainly been an eventful few days.

First, the weather has been fickle. We had mostly sunny days with strong winds until Serene, May, Trevor, Minako, Geri and Maria left. Then “poof!”, the winds disappeared and seas flattened, but cloud cover moved in with scattered showers.

It’s definitely better to have low winds with clouds than blistering winds with sun, but all things considered, I’d really appreciate a period of low winds and sunshine at the same time. I’ve filled in the appropriate forms in triplicate and filed them with the relevant sun, sky, sea and wind bureaucracies…so we’ll see what the upcoming week brings.

We’re up to 28 ID-ed calfs now (woohoo!), and we’ve also had some repeat sightings of a couple of babies we catalogued earlier.

In addition, I received a report from my friend Wendy who was in Ha’apai (separate island group in Tonga) aboard the Nai’a about a potential sighting of a half-tailed female whale we’ve previously named Konga Hiku.

It would be exciting enough to see Konga Hiku back in Tongan waters, but Wendy says the whale in question has a calf with her, so that would make a confirmed re-sighting all the more meaningful. Wendy wasn’t able to take a photo, but she’s put out an APB via Nai’a to ask passengers for the rest of the season to get a photo if possible. Keeping fingers crossed!

Baby, Baby, Baby
As I mentioned above, we’re at 28 babies right now. That’s pretty amazing.

To put this into some perspective: Our all-time high to date was 31 babies in 2009.

During that year, I was in Tonga from 8 August to 11 September. We counted 26 babies by the time I left. Friends and other visitors to Vava’u then kindly contributed five additional IDs, making a total count of 31.

This season, I also arrived on 8 August, the same date as I did in 2009. Our count of 28 baby humpbacks so far is through yesterday, 4 September…which means we’ve already exceeded our 2009 final tally of 26 by two babies…with several days to spare.

At this pace, I’m almost entirely certain that we’ll pass 31 within this week, and I’m really hoping for more than 40 by the time I leave at the end of September.

Still on track for a record number of humpback whale babies
(black = 2008; blue = 2009; red = 2010).
Extracted from my 2010 humpback calf summary.

Besides confirming several new calf IDs, we’ve also had some repeat-sightings this week:

- 31 August: Hiva, calf #9, originally ID-ed on 19 August (13-day interval)
- 01, 02, and 03 September: Tahafa, calf #14 (the injured calf), originally ID-ed on 23 August (10- to 12-day interval)

Less-than-ideal visibility (even far offshore) has continued to make taking underwater photos difficult, and the “neutral” whale behaviour I alluded to in previous updates has for the most part continued.

We still haven’t had any Ikumi-esque encounters…meaning extended quality time with a chilled-out mom and an engaged baby. I know that there have been some good encounters, but they’ve been few and far between, especially considering the number of whales around.

One possible contributor to this may be the number of mom/ calf pairs that have been accompanied by escorts, especially in recent days. In most cases, the escorts seem to have been “pushing” the female whales and their babies along, reflected in the whales’ non-stop swimming and erratic twists and turns. (Refer to the Two Timer discussion in Part 3).

It’s important to note that this type of behaviour is taking place with or without boats nearby. We’ve watched mom/ calf/ escorts from afar…looking on as the whales zigged, zagged, sped up, slowed down…basically did everything but stop and sit still.

Uaono (calf #26) with mom. Low viz, cloudy skies
and nonstop whales makes ID-ing difficult

With Uaono (calf #26) for instance, we watched as the mom/ calf/ escort trio pinballed haphazardly around the area between Tungasika and White Patch. At one point, we saw mom and baby head one way, and escort head another. Right after I pointed and remarked: “Hey, what’s going on?”, the escort breached several times, while cow and calf swam away.

One of the things Ongo, my whale mentor in Vava’u, used to say to me was: “When a female rejects an escort, the males often breach in frustration.” I was sceptical when he first shared this observation with me many years ago, but I’ve seen this scenario play out often enough now that I’m certain he was correct.

Unfortunately though, Uaono and mom didn’t appear to take comfort in the escort’s disappearance. They slowed down for a bit, then took off at top speed toward White Patch and straight out to sea, making it impossible to get a good look in the water.

Talking Toku
Recent arrivals Dan, Kozy, Sean, Nana and Ray had their first day on the water on Friday.

It was cloudy, but the winds were down, so we decided to head to Toku, a small island located about 40km from Vava’u. I had only been there once before (last year) and had a kick-@** time, so I decided it was worth taking the group there, even if they still hadn’t had the opportunity to learn the ropes.

The calculated risk paid off.

Breaching humpback whale that put on quite a show

Before reaching the island, we saw blows all over the place. We started to follow a pair of whales, hoping for an in-water encounter right away. As luck would have it, we weren’t able to see them underwater, but that was because the larger of the two whales put on a spectacular, non-stop breaching show for us.

I’m not sure how long the breach-bonanza lasted, but we followed for quite a while, perhaps an hour or more. The pertinent whale repeatedly took two to three breaths, dived, and fifteen seconds or so later…breach!!! Everyone took photos. Nana even posted iPhone snaps. How many people can boast of taking close-up humpback whale breaching photos on an iPhone?

After that, we spent the rest of the day with two mother/ calf/ escort trios, both in pretty much the same area. Though both groups of whales moved non-stop (despite my desperate pleas of: “Cut me some slack guys!”), we managed a number of drops with Uatolu (calf #23, a little baby girl) in shallow water.

If conditions permit, we’ll definitely head for Toku again in the coming days.

Little baby Uatolu (calf #23, female) going for a stroll with her mom

Update: Injured Calf
Below is a close-up photo of the Tahafa (calf #14), the injured baby that I discussed in last week’s update.

Shawn and John observed this baby on 01 September (10 days after we first ID-ed the baby), and noted that the juvenile seemed lethargic and lacked energy/ spunk. This, of course, had us worried.

Over the next two days, however, Emiko and Takaji had two additional encounters, during which time the baby breached and played a lot, appearing for all practical purposes to be as healthy as any other little whale…much to our collective relief.

The precise cause of the baby’s injuries is still a topic of discussion/ debate here. I continue to believe that the balance of probability lies with an attack by a group of marine mammals, but another theory put forth by credible/ experienced people here suggests a boat collision as a possible cause.

While we may never know the actual cause with complete certainty, we certainly all hope that this baby thrives and returns in the future. We’ll most likely be able to recognise this whale by the missing anterior portion of its dorsal fin.

Top-down view of Tahafa’s (calf #14) injuries

White Pecs
Well…we’re up to eight whales with all-white or nearly all-white pectoral fins now.

That’s fascinating enough, given the relative paucity of white-handed whales here in most seasons, but even more exciting…the latest white pec is a calf I ID-ed yesterday, Uafitu (calf #27). This is the first time I’ve ever seen a calf here with all-white pectoral fins.

We came across this calf entirely by accident, while we were waiting for a singer. This special baby, along with mom and escort, literally “popped up” of the blue, taking us by surprise.

From above, we could see that the baby had all-white pectoral fins, so it was particularly nerve-wracking when the whales eluded us for several minutes, despite flat-calm conditions.

True to the escort-induced-ping-pong-pattern of motion that’s been all-too-common of late, this trio was difficult. There was no predictable method to their madness, so following them was more gut instinct than measured approach. It took a few tries, but in the end, I was able to get up-close ID-shots of the baby.

Uafitu (calf #27), the first humpback whale baby I’ve seen with all-white pectoral fins

I’ve been keeping an eye out for whales with all-white pectoral fins here since I noticed a similar surge in their numbers back in 2006. This fluke morph is relatively more common in the northern hemisphere, so it was natural to wonder whether there could possibly be crossover from north to south.

Back in ’06, some researcher friends were kind enough to forward me a couple of research papers that suggested such a phenomenon might be possible. But even so, it shouldn’t be a common occurrence if it takes place at all, given the disparity in seasons and locations of the two populations at any given time in the year.

Sighting this baby now provides me with proof-positive that white-handed babies are born in the south. Probably not too exciting for most people…but a major thrill for me!

Headcount: +11, -2
As you may have gathered, this past week was a period of transition for my groups of visitors.

Besides sending off eight people during the week, I was scheduled to have five people arrive from Japan and six people from other countries…Taiwan, Thailand, the US, Canada and Russia.

But on Tuesday, I lost the Russian. Followed by one of the Japanese. Instead of 11 people, I ended up with only nine.

We all miss you Andrey, Yokomoto-san!

Both people had their travel plans interrupted due to minor bureaucratic snafus. In Andrey’s instance, transiting through Australia required a visa, even though he wasn’t ever setting foot in the country. Silly, but this requirement is more common than you might imagine.

In Yokomoto-san’s case, Tonga (like many other countries) requires tourists to have at least six months of validity remaining for their passports. He had four or five.

In both cases, the relevant bureaucracies were unable/ unwilling to help, which sadly meant cancelled trips.

To try to learn from this unfortunate turn of events…if you are planning an upcoming trip to any destination, please make sure that you don’t need visas for transit, and also that you have at least six months left (from your planned date of entry to the country concerned) before your passport expires.

Intrepid travellers who left this week:
Geri, Minako (oops! only hat visible), Serene, Trevor, May and Maria

If I had to pick a single word to characterise this past week in Vava’u, I’d say “tough”.

Early in the week, the winds picked up significantly, staying a pretty constant 25-30 knots, only coming down to the 15-20 knot range on Saturday. If you’ve never been at sea in a small craft, 25-30 knots is bearable, but certainly not comfortable.

With swells hitting two to four metres in some places, it’s difficult swimming as well…which in practicality meant that our search area was restricted, and there were times when whales were around, but we had to forego getting into the water, because safety always comes first.

Subjectively, it seemed like there were fewer whales in the area than in the past couple of weeks. Fewer blows, fewer encounters, with several days during which most of the whale-watching boats didn’t have any substantive encounters.

Maybe the cetaceans are all off doing something…heat runs out in the blue perhaps?…and will be back soon. Of course, the fact that all the boats have been restricted by the winds and sloppy seas may have also contributed to this impression. It’s conceivable that there were whales in the areas that we were unable to visit.

Within this context though, there were still lots of babies around. I was able to ID six more little humpback whales, bringing the tally to 18. There were also at least four babies that we came across, but weren’t able to ID due to prevailing conditions. Bummer for my ID count, but good to see that the population of juveniles is continuing to grow.

Banner Baby Boom
The good news this week is that the banner baby boom is proceeding according to schedule. Updating my graph from last week (taken from my 2010 humpback whale calf count summary file), it looks like the number of humpback whale babies that I’ve been able to ID may be progressing along the same slope as in previous years, but phase-shifted forward a bit.

The number of humpback whale babies continues to grow.
(black = 2008; blue = 2009; red = 2010)

Given that the slope has been similar over the past three years, I sort of expected to see this progression, but it’s certainly good to have confirmation with real data…at least to this juncture. I still have a month left, though. Who knows what can happen in that time?

Weather will certainly be a big factor, and losing Sundays out on the water restricts our search time, but if this pace continues and the slope of calf IDs ends up being similar to previous years, we will reach the highest number of ID-ed calfs since I started this effort.

I’m so keeping my fingers crossed!

The dirty water I made reference to last week continues to plague us. The high winds have stirred up sediments, making some areas in really murky. There are certainly places with better visibility, but we’re searching every nook and cranny in order to cover as much area as conditions permit.

Most of our sightings this week have been in the east and in the inner waterways, due in large part to our inability to get further out. The weather forecast says the winds will begin settling soon, so when they do, we’ll be able to extend our search a greater distance from home base.

Third encounter with Tahaua (calf #12) and mom.
Tahaua is an adorable baby girl.

Injured Calf
We came across an injured calf on Tuesday, August 23. Actually, we had heard about it the day before. There was chatter among the whale-watch boats about a wounded calf, possibly attacked by a big predator like a tiger shark.

When we came across the baby whale (which I ID-ed as Tahafa, calf #14), the wounds were clearly visible. There were a couple of large chunks missing from its dorsal surface, and the front part of its dorsal fin was gone.

Front view. Wounds clearly visible on Tahafa’s (calf #14) dorsal surface.
The anterior portion of its dorsal fin appears to have been bitten off.

I can see why everyone would be concerned, but one look in the water was all it took to see that the calf was perfectly healthy, happy and energetic.

It’s impossible to predict whether this calf will make it all the way through the high-risk period of growing up and then travelling down south to feed and mature, but unless some serious infection sets in, these wounds won’t cause it much trouble.

Moreover, one look at the wounds and it’s pretty obvious that they’re unlikely to be from a tiger shark. Tiger sharks are scavengers and opportunistic feeders. It’s difficult (though not entirely impossible) to conceive of a tiger trying to take a perfectly healthy, fast-swimming calf with a big mom next to it.

The bite sizes look more like they were made by something else. After discussing with Shawn, we’ve come to the conclusion that the most likely culprits are a pack of marine mammals, perhaps pilot whales. I’ve seen lots of pilot whales here (we swam with a big pack last season), and they are certainly cooperative hunters, so it’s a possibility.

In addition to the actual wounds, there were many scratches and scars on the baby’s body that looked like they might have been aborted/ failed bite marks.

The visibility was pretty bad when we came across this mother/ calf pair, but in any case, the baby looked and behaved just fine.

Tahafa (calf #14) with mom. The calf has visible wounds on its dorsal surface,
but was otherwise healthy and energetic.

Two Timer
One particularly interesting encounter for me over the past few days was with a horny male. I’m referring, of course, to an escort whale.

Early on Friday the 26th, we came across a humpback whale mother, baby and escort in the general area of Tapana and Euakafa. The winds were high and the seas frothy…meaning it was difficult to follow the trio.

Given the prevailing conditions, it would’ve been nice if the whales had taken pity on us by sitting still, or travelling slowly if they needed to travel at all…but no. They pinged back-and-forth in erratic patterns, diving for short periods sometimes, disappearing for ten minutes or more in other instances…but in all cases, not making it easy for us.

We went downwind, upwind, sidewind, over waves, into waves, through waves…going every which way you can possibly imagine…for around three hours…with the incessant bouncing pounding my brain into a mushy pulp in the process.

During that time, the whales lost us a few times…like totally ditched us…reappearing way far away from where we expected.

The thing is, it wasn’t as if they were in any rush, and they weren’t avoiding the boat per se. This is just what they were doing…before we found them, while we followed them, and long after we left them.

I managed to get into the water with them only twice.

The first time, the mother turned to take a look at me. From experience, I was sure that her body language indicated curiosity and interest. The baby’s certainly did. But then they took off again and kept up the aquatic ping-pong act.

On the second drop, the mom actually stopped, probably to take a breather. When she brought the baby up, she passed right by, staring me in the eye, and once again…looking for all practical purposes to be friendly.

Imagine how puzzled I was when the trio took off once more in a perfect illustration of Brownian motion.

Despite the aquatic acrobatics, I managed to get good enough photos to ID the calf as Tahafitu, calf #17 of the season.

Tahafitu (calf #17 of the 2011 season) with mom in awful visibility.
The escort that was pushing them along is visible below.

Fast-forward to the next morning, when we came across another mom, calf and escort in roughly the same area.

When I saw this trio, the first thought in my head was: “Oh no, please not again!”

The first dorsal fin I saw break the surface was the escort. I couldn’t be 100% certain, but it looked to me like it was the same escort as the previous day…an observation that only exacerbated my sense of dread.

When the mom and baby appeared though, I breathed a sigh of relief, because the mom’s dorsal was completely different from Tahafitu’s (calf #17) mom.

My relief was short-lived however, as this trio took us on a guided tour of the vicinity that put the previous day’s experience to shame. Back-and-forth, back-and-forth, back-and-forth, over-and-over, over-and-over, over-and-over…you get the picture.

We managed three drops into the water, which was really mucked up. Visibility was poor (such an understatement), meaning it was difficult to get ID photos. To make things worse, the first drop happened so suddenly that I didn’t have my camera on (I really need a sign that says…Caution: Professional at work), and on the second drop, the whales swam up-sun of us, meaning we had a terrific view of backlit sand, grit, and other miscellaneous stuff in the water between us and them.

The third and final drop didn’t look too good either: visibility was still bad, and the whales swam away.

But…I had another one of those moments, like the one I described to in Part 1, in reference to ID-ing Fa (calf #4) on Day Six. Even though the whales had long passed, I continued to swim, partly out of hope, mostly out of desperation and frustration.

I maintained visual contact with the trio in the haze, and after perhaps 20 seconds or so, I saw the mom execute a slow, graceful 180 and head straight toward me.

She apparently caught the escort off guard, as the third whale continued on its previous trajectory.

I stopped and watched as the mom approached, bringing the baby (which I ID-ed as Tahavalu, calf #18 of the season) to within touching distance of me, once again slowing down to make eye contact and give me time to take photos.

Tahavalu’s (calf #18) mom brought the calf directly to me,
in really bad visibility with the sun on the wrong side

Then, without warning, the mom and baby thumped their flukes and took off at high speed. It was only then that I saw the escort approaching at high speed, flying past and heading off in hot pursuit of the cow and calf.

So…here’s what I figured out: After I got back and downloaded photos, I confirmed that my initial observation was correct. The escort was the same on both days. I cross-checked markings on the dorsal fin, torso and right pectoral fin. There’s no mistake.

Two days; two different females; same randy male.

My “feeling” on both days was that the females were friendly, probably favourably disposed to us. This didn’t jive with their frenetic behaviour though.

I got the sense that the escort, however, “pushed” the females and their babies forward on both occasions, a feeling that was supported by the marked change I saw in Tahavalu’s (calf #18) mom’s behaviour when the escort wasn’t around and when it was.

In short…it’s quite possible that neither calf #17’s mom nor calf #18’s mom cared for this particular escort’s overtures, which may help explain the whales’ erratic movements on both days. The mommies were trying to send a clear message to the suitor: “Scram!”, but the escort was too thick-headed and/ or juiced with testosterone to comprehend.

(It’s a good thing that’s never happened to me.)

Besides the obvious fact that I documented a two-timing humpback whale male, it’s also interesting to note the difference in the way these two females treated this escort, with the intimate manner in which Tolu’s mom (calf #3 of the season) interacted with her escort, as I described in Part 2.

The take-away observations for me are first, that humpback whale females clearly have preferences. Some guys do it for them; others don’t. I figured this was the case, but it’s nice to have such clear confirmation.

And second, that in-water observation provides insights that would be difficult to achieve by other means.

Incidentally…I’ve also seen sperm whale males “loved” by all the females in a family group, and others unanimously rejected by them. Take from that what you will.

Note: After drafting this post, I remembered that Shawn had shown me a photo he took on 25 August of a mom, baby, escort from outside Hunga. The shot was from behind, and a bit far, so we couldn’t ID it at that time, but I recalled that the escort looked similar to this one I described above. I took another look, and sure enough, it was the same escort. The mom and baby on that day were Tahafitu (calf #17) and mom. So Shawn documented this calf one day before I named it. Cool, huh?

Comparison of escort whale’s dorsal fin:
Left taken with calf #18 on 27 Aug; Right taken with calf #17 on 26 Aug.

Searching for Patterns/ Speculation
I still have a month+ to go here in Tonga, but it’s getting to be that time again when I start looking for patterns and speculate about what’s going on based upon what I’ve seen during the season. It’s early yet, but here are a few things that I’ve been mulling over this week:

Pace of Calf IDs
The numbers and timing of mother/ calf pair IDs vary each year, but one observation that seems to be emerging from the data I’ve collected in the past few years is that the slope of the graph depicting the pace of IDs is similar.

Perhaps this doesn’t come as a big surprise, but it’s good to have patterns derive from data, rather than conjecture or assumption. If this year’s calf-sighting slope is once again similar to those of previous seasons, then it underscores the possibility that this is a pattern.

I know from friends who live here that the whales in general showed up early this season. Consistent with this fact, it seems like the slope of our IDs is holding true to past years, but phase-shifted forward a little. It will be interesting to see how this develops over the next few weeks.

Second encounter with Tahatolu (calf #13)
with mom and escort swimming below. Tahatolu is a playful little boy.

Patterns of Behaviour
Patterns of behaviour among the whales here change from season to season.

In 2009 for instance, there were lots of mother/ calf pairs around, many of which were very settled, meaning they’d just sit still and let the babies play.

In 2010, there weren’t as many mother/ calf pairs as the previous season, and they seemed much less settled, in general unwilling to sit still (with the exception of Ikumi and mom).

This year, it’s looking as if we’ll end with more mother/ calf IDs than the 31 pairs in 2009, but the whales seem to be “neutral”, for lack of a better term. Of the 18 mother/ calf pairs I’ve ID-ed this season, none have really been terribly interactive, and only a few actively avoided contact.

Most seem not to be avoiding people per se, but it’s more like they’re going about their business, not too concerned about whether we’re there or not. In practicality, this means that it’s been difficult to “get to know” any particular baby well.

There have been a few extended, interactive encounters with mother/ calf pairs, but overall, not a high proportion relative to the number of babies in the area.

Also of note, it seems like there’s been a lot of breaching this season. I’ve seen breaching whales almost every day I’ve been here, sometimes several times a day. I recall that in 2005, there was a lot of breaching as well. I took a lot of breaching photos that year. In other seasons, there’s been some, but not nearly as much I’ve seen this year or in 2005.

Patterns of Physical Characteristics
In many years, there seem to be shared patterns of physical characteristics that appear among a number of whales, but seem not to appear again in appreciable quantity in other seasons. I can’t be 100% sure of the following observations, because I don’t see every whale, but the apparent occurrence of common physical traits on a season-by-season basis is something that’s nagged me for many years.

Last year, there seemed to be a disproportionate number of predominately black whales. This year, there are certainly some around, but most of the whales are some variation of the southern-hemisphere archetype of being dark on top, with white on the belly and some on the sides.

In 2006, I photographed a number (I recall something like six to eight) of whales with all-white pectoral fins, meaning white on both sides. In other years, I haven’t seen many. So far this season, I’ve photographed three, and Shawn has photographed one. There may have been another sighting, which I’m trying to track down now.

The third whale with all-white pectoral fins I’ve photographed this season.
This looked like it was the male in a courting pair. Visibility underwater was horrible!

Last season, we saw several (4-5) whales with split dorsal fins, most likely not due to injury. I don’t recall seeing split dorsals in any other season.

This year, I’ve photographed five whales with a black central region on the ventral surface of their flukes. I haven’t noticed this pattern before, but it’s entirely possible that I just wasn’t looking.

Tolu (calf #3 of the season) is one of five whales
I’ve photographed this season with this fluke pattern.

What does all this mean? I’m not sure. Perhaps it’s a clue to something very important; perhaps it’s just coincidence.

But as I stare at images each night, I keep looking for patterns, because where there are patterns, there is often meaning.

Quick-and-dirty summary of the past week: Moderate, fickle winds shifting directions on a regular basis; some rain and cloud cover, but nothing too bad; more whale-watching boats on the water this week than the previous week; fewer tourists and less yacht traffic viz the average for this time of year; lots and lots of baby humpback whales; more breaching activity than I’ve seen in several years.

Fitu (calf #7 of the 2011 season) with mom.
Note the unusual clover-like mark on the calf’s dorsal surface.

Dirty Dozen
The big news of the week is that our mother/ calf ID count is up to 12 pairs now. That’s triple the number I ended last week with, and double to quadruple the figure at this same time in the past few years.

As you can see from the graph below (which I excerpted from my 2010 humpback whale calf count summary file), we’re on track to surpass the 2009 count of 31 mother/ calf pairs. I’m hoping to end the season with at least 32.

Our calf ID count is proceeding at a record pace this season.
(2008 = black, 2009 = blue, 2010 = red)

Hitting 32 would be great. It would be satisfying to achieve a record calf count this year, as I set out a case for the possibility of a banner baby year this season when I wrapped up in 2010. But more importantly, surpassing our 31-calf count in 2009 would be a positive indication for the health and recovery of the southern hemisphere humpback whale population…which is, after all, the most important thing.

I know there are more babies around, but it’s simply not possible to get to every calf that’s spotted each day. Plus, we are confined to land for seven Sundays this season due to the restrictions on tourism in Vava’u, meaning I’m losing a week’s worth of working time.

Reinforcements have arrived though. My friends Shawn and John just got here to continue filming for a documentary project (they were here last season too), so I’ll have more eyes on the water for the next couple of weeks.

Having an extra boat out on the water with reliable, competent people will be invaluable.

Lima (calf #5 of the 2011 season) and mom with two escorts, travelling at high speed

There are a few things I think worth mentioning at this stage about our calf sightings.

First, many of our encounters this season have been in murky water, with really bad visibility. This makes ID-ing even more challenging, as we need to be able to make out unique features on the mother/ calf pairs to be confident about the IDs.

To complicate matters, quite a few of the moms have seemed particularly shy. It’s normal for some proportion of the female humpbacks we encounter to be evasive, but subjectively, there seems to be a high ratio this year.

The practical implication of bad visibility + shy moms for my ID effort is that for quite a few mother/ calf pairs, we only have a few shots…from behind, at a distance, in murky water. Certainly not ideal, but fortunately, still workable…with lots of squinting and hand-wringing.

Another implication is that it’s been more difficult than in previous seasons to determine the sex of the baby whales we’ve seen. In order to sex the little ones, I need to be able to see/ photograph their undersides, which means being reasonably close and having time to observe. So far, I’ve only been able to determine the sex of three of the 12 babies: two males and one female.

Finally, there have been people who’ve argued over the years that there are few/ no baby whales in the inner island areas, especially in places with frequent boat traffic. This argument has been used as attempted justification to create restrictions on boat traffic and/ or to ban whale watching/ whale swimming.

Over the past couple of seasons, we’ve used GPS to mark our calf encounters, and have demonstrated that humpback whale mother/ calf pairs make use of all the waters around Vava’u, including the inner waterways.

This season is shaping up the same way. This past week, for example, we’ve come across mother/ calf pairs next to Luamoko, by Tungasika, near Matamaka, and off of Oto.

I’m certainly not saying that boats and people don’t need to be careful in the inner waterways, but I am saying that discussion of this nature need to be resolved based on fact, not emotional fervour.

Sunset in Vava’u on Wednesday.
Red skies at night were a good sign for the following day.

Sex Change
I made a mistake last week.

Tolu (calf #3) is not female. She is now a he; or more accurately, he was never a she.

I’m not sure how I made that mistake, but it’s probably because my days are so packed, and I’m doing all my file downloading, GPS recording, note-taking and calf ID-ing at night, when I’m just bloody exhausted.

Anyway, I caught the mistake because we had a third encounter with Tolu this week, meaning that Tolu and mom have been in Vava’u for at least eight days (first encounter on 11 Aug, second on 13 Aug, most recent on 18 Aug).

Tolu’s mom was quite shy during our first two encounters, making it difficult to get really good photos. Tolu, if you recall, is an extremely playful calf that reminded me of Ikumi from last year, with a wound on his abdomen that looks like it resulted from an unfortunate encounter with a fishing line or other similar rope.

Anyway, in this third encounter, Tolu and mom were accompanied by an escort. In many instances, escorts stir things up. They often push the mom and baby along, keeping the whales moving and making it relatively difficult to have good encounters. This was the case with Lima, calf #5, which was accompanied by two escorts, as well as for Fitu (calf #7) and Valu (calf #8) which were both travelling at high speed with escorts.

Little Tolu being allowed to go off and play on his own,
while mom and escort make like lovebirds below

In this case, the escort seemed to have a calming effect on Tolu’s mom. She was relaxed, chilled out, totally unconcerned with where her baby was playing. She let Tolu tail-slap and flop around at the surface alone, head over to play with people, and generally do as he pleased…while she and the escort cruised along, often touching one another, in what appeared to be lovey-dovey bliss. Complete contrast to the first two encounters.

I write that half tongue-in-cheek, but that’s really what it seemed like. Tolu’s mom must have really, really liked this particular escort. His presence completely pacified her.

The upshot was that Tolu was allowed to play with us, and I was able to take really good photos of his abdomen, showing that Tolu is a definitely a he.

[Note: In case you’re not familiar with the concept of an escort whale, it’s basically a horny male that’s hanging out with a female with a kid already, perhaps in hopes of getting some action.]

Humpback whale calf Tolu playing at the surface,
while mom (right) and escort cruise together below

For comparison, here is photo of Tahataha (calf #11), showing her developing mammary slits. Boys like Tolu don’t have those.

Tahataha (calf #11 of the 2011 season) with mom,
in extremely bad visibility. Inset shows the calf’s mammary slits

The Week Ahead
For the upcoming week, friends from Japan, the US and Singapore are here with me. We’ll be out on three boats looking for great encounters, and hoping to add to the calf count if weather, winds, water and whales permit.

I’m also hoping that in addition to mother/ calf pairs, we’ll see some high-action heat runs and more breaching. Swimming with mother/ calf pairs is wonderful, but there’s nothing quite like the adrenaline rush of watching a bunch of whales travel at high speed while snorting, groaning, slapping and body-slamming one another!