On July 16th, 2010 I saw Sperm Whales for the first time off the coast of British Columbia and my world rocked.
This whale species is unlike any other and is extreme in so many ways.
- Make very long and very deep dives
- Have the biggest brains
- Are the largest toothed animals
- Make the loudest sounds
- Have a very strange common name reflecting great misunderstanding
- Were hunted intensely
- And are so very, very unique looking.
I saw the Sperm Whales while having the joy of being a Marine Mammal Observer on DFO’s Cetacean Research Program’s offshore survey. I first saw them in the area where I have put the blue star on the map below. You’ll note from this image that this area off the continental shelf is where many sperm whales were “taken” by whalers. It is in deep waters like this that sperm whales find their prey of deep ocean fishes and squid (from medium-sized squid species to the giant squid).
Our first clue that we might be sighting Sperm Whales was the very unique blows that veer sharply off to the left. Through binoculars we could confirm the species ID by seeing the animals’ colossal heads and wrinkly skin and, when they descended for a long and deep dive, it was indisputable that we were seeing sperm whales. The distinctly shaped tails came high out of the water, straight up and down and the animals descended as if slowly going down in an elevator. I found myself screaming in amazement when I first saw this. (Note that the images below showing the Sperm Whale’s dive and blow are not from the research trip in B.C.)
Down he went. Down, down, down. The dive could take up to 90+ minutes and could be to a depth of 3 km. That’s 300 atmospheres of pressure! (One weblink I provide below provides video of a Sperm Whale at this depth.)
Apparently an average Sperm Whale’s dive profile is to slowly descend for 10 minutes, hunt at depth (more often at 300 to 800 m) for approximately 25 minutes, then slowly ascend for 10 minutes. The whales then stay at the surface for some 8 minutes, taking up to 90 breaths (range of 20 to 70) to offload carbon dioxide and reload oxygen into their blood and muscles.
This long period at the surface is when they were an easy target for the whalers. Yes, Moby Dick was a Sperm Whale but the ferociousness portrayed by Herman Melville in this classic novel is pure fiction. Were Sperm Whales to attack and swallow people whole, they may not have been so terribly exploited. We humans wanted their blubber, their spermaceti and their ambergris. Ambergris is found in the intestines (see previous blog item) and “spermaceti” is a semi-liquid wax found in the Sperm Whales’ huge heads. Early whalers thought it was a reproductive material which is why the species has its strange common name. Science now believes that this material has a role in buoyancy by being cooled and contracting to become more dense when the whale is diving and then becoming heated and expanding to allow the whale to ascend from such great depths. It may also have a role in sound production.
In the dark world to which the Sperm Whales descended, they find their prey through echolocation. These clicks act like an “acoustic flashlight”. They go out from the whale’s huge head and, when they bounce off an object and “echo” back, this allows the sperm whale to form an image of its surroundings and prey. (I also provide a weblink below that provides amazing, but very worrying, video of a Sperm Whale using echolocation to take fish off a longline = “depredation”).
As well as these slow and regular echolocation clicks, Sperm Whales also make really loud clicks called “codas”. Codas are believed to allow the Sperm Whales to communicate with one another, maybe in a way like we humans use Morse code.
I don’t know that anyone can be quite the same after an enormously privileged experience like seeing a Sperm whale. I was left stunned with a cocktail of emotion surging through me that included wonder, joy, passion and resolve. More passion for conservation and more resolve to share these experiences to make them count.
Links to Sperm Whale sound and video:
- Photos of a stranded sperm whale on an beach in England (May 2011). Tragic but the images capture how remarkable these giants are.
- Click here to go to “Voices of the Sea” and, then click on the sperm whale image to be taken to where you can see the “Meet the sperm whale video”. Really worth it!
- For video of a sperm whale “depredating”, taking fish from a long line, click here. Truly amazing video where you first see the black cod on the longline, hear the echolocation clicking of the sperm whale and then see it come in and take the fish off the line. Click here to learn more about the whales being habituated to the sounds of the boats and having learned to steal fish in this way.
- Radio interview about the acoustics of sperm whale depredation (KCAW-FM, 2011-04-19, Alaska)
- Click here for footage taken by a ROV (remote operated vehicle) of a sperm whale at a oil rig by at a depth of more than 2,900 m.
Great resource for further information on Sperm Whales off British Columbia’s coast: John Ford’s 2014; Marine Mammals of British Columbia: Royal BC Museum Handbook; available via the Royal BC Museum and Amazon.ca .
AOKI, KAGARI; MASAO AMANO; KYOICHI MORI; AYA KOUROGI; TSUNEMI KUBODERA and NOBUYUKI MIYAZAKI (2012) Active hunting dep-diving sperm whales: 3D profiles and maneuvers during bursts of speed. Marine Ecology Progress Series 444:289-301.
Watwood SL, Miller P, Johnson M, Madsen PT, Tyack PL (2006) Deep-diving foraging behaviour of sperm whales (Physeter macrocephalus). Journal of Animal Ecology 75: 814-825.
Whitehead, H. (2003). “Vertical Movements: The Sperm Whale’s Dive”. Sperm Whales Social Evolution in the Ocean. University of Chicago Press. p. 79.