The Crab and The Nudibranch

Crabs are comical. There's no doubt about it.

Following on the crab/ pipehorse test of wills I saw two nights ago, last night I watched as a crab and nudibranch matched wits.

From the outset, I had little doubt that the crab would come out the better of the two, but it was still a lot of fun to watch this mini-drama unfold.

It all started when I saw a nudibranch (Marionia pustulosa) making its way across the bottom. We've seen a lot of these nudis recently, so I didn't give it much thought, and I was about to swim by...when I noticed something ambling across the sea bottom toward the nudibranch.

Within seconds, I watched as a crab walked in front of the nudibranch and grabbed the unsuspecting sea slug's rhinophores to pull it down to a more crab-friendly level. The crafty crustacean proceeded to mount...yes, to mount...the nudibranch.

crab and nudibranch

Of course, no self-respecting opistobranch wants to be seen in public with an unattractive accessory like this crab (much less to have its photo taken with one), so the hapless nudibranch resisted.

The besieged sea slug took off at top speed (for a nudibranch), but the nimble crab quickly changed strategy. It grabbed on from the side as the nudibranch sped away (again at top nudibranch velocity) and clambered atop the fleeing slug.

crab and nudibranch

Once astride the nudibranch, the crab sat back(ward) and rode off into the proverbial sunset (there was, of course, no sunset, since it was just after 22:00 and underwater, but the mental image makes for a nice ending).

crab and nudibranch