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!