WHALE TALES FROM ABACO (1): BLAINVILLE’S BEAKED WHALES
Back in March we were invited by Charlotte and Diane of the Bahamas Marine Mammal Research Organisation BMMRO to spend a day out with them on the research boat, a chance we jumped at. I had been writing on and off about the organisation’s whale, dolphin and manatee research since the very early days of this blog. We’d seen bottlenose dolphins in Abaco waters, but never whales. This was the big day…
Our first sighting was a short distance south of Rocky Point, as we moved beyond the turquoise water of the low sandbanks into the deeper, darker ocean waters of the Bahama canyon beyond. Whale territory. The shoreline was plainly in view to the east; and to the north, on the horizon, was the massive bulk of the ‘fun ship’ parked at Castaway (Gorda) cay.
The Blainville’s beaked whale (Mesoplodon densirostris) is also known slightly less politely as the dense-beaked whale. It is named for the French zoologist Henri de Blainville who first described the species in 1817 based on his examinations of a piece of jaw or ‘rostrum’ — the heaviest bone he had ever come across — which resulted in the name densirostris (Latin for “dense beak”).
The BMMRO has carried out intensive research on the species for a number of years in the northern Bahamas, with detailed documentation of sightings and photo identification of individual animals. More recently, these whales have been the subject of incredibly detailed research into their species intercommunication through vocalisations – mainly clicks and click patterns. To view Charlotte’s PhD thesis for St Andrew’s University click HERE (and many congratulations, Dr Dunn…). Just reading the contents table will give a good idea of the scope and complexity of the research.
Our amazing first encounter with 6 whales lasted nearly an hour. Usually, they stay near the surface for 20 minutes or so, then they do a deep dive lasting roughly 20 minutes before resurfacing. But on this occasion they behaved more like huge dolphins, swimming towards the boat, around it, under it, then drifting away again before returning.
Given their length of some 15 feet and weight of about 2000 pounds, it was a extraordinary experience to see them at such close quarters.
Whale showing healed circular wounds caused by COOKIECUTTER SHARKS
The Blainville’s range is extensive and in general terms they may be found in tropical and sub-tropical waters worldwide. They are by no means uncommon, but apart from the data collected by the BMMRO it seems that comparatively little is known about them. Their diet is thought to consist mainly of squid found at depth. They are protected by a variety of Agreements, Memoranda of Understanding, Protocols and so forth throughout the worldwide range.
The research boat is equipped with sonar the can pick up the click and whistles of whales and dolphins from a considerable distance. It was remarkable to watch a group of cetaceans and to be able to hear them loudly and animatedly communicating with each other..
Another vital aspect of the research is poop scooping. As soon as the whales had gathered round the boat, Charlotte slid into the water with her scoop net… the cloudy poop yields a mass of information about an individual creature. I wrote about this interesting job, often tasked to interns (who practice with coffee grounds) in ‘FAMILIAR FECES’.
Then, all too soon, it was deep dive time. The whales moved off from the boat and slowly, without show or splash, disappeared. And we went to investigate HOLE-IN-THE-WALL at close quarters. The next post will feature an adult male Blainville’s beaked whale, with his massive barnacle-encrusted teeth protruding upwards from his lower jaw.
In this very short video of two whales right by the boat: you can actually hear their breathing.
Credits: All photos RH; Charlotte & Diane for a brilliant day out; Mr Blainville for a brilliant whale