Cetacean Society International

Working for whales, dolphins and porpoises worldwide

CSI Photo Gallery

Sperm Whale

(Physeter macrocephalus)

Sperm whales are creatures of extremes, the largest of toothed whales, with enormous heads and brains; they are perhaps the longest and deepest diving species. Certainly some live over 70 years. As he dives, or sounds, this young sperm whale's flukes show a very distinctive edge that may allow us to follow and understand his life. Scientists catalogue individuals by marks, sounds, and behavior. Sloughed skin and defecations are also used to tell an individual's health and genetic makeup, enabling an understanding of relationships between groups spread over large distances. Rough areas by dorsal fins are found on females and young males, but never old males, and that's just part of what we don't understand. (Photo courtesy Colin D. MacLeod, UK.)
Three females and one young sperm whale are seen from the air, swimming slowly and taking many breaths after a long dive in the Bahamas. Females form stable groups, perhaps for life, with their male children leaving around age six. These female groups often stay in one general area of temperate waters for years, raising young. Males live in almost all ice-free seas, forming age-class groups that break down over time until the oldest males may be very solitary, at least until they swim to warmer waters to find female groups. While females may be 36 feet (11 m) long, adult males are up to 60 feet (18.3 m). In human terms imagine every man being about nine feet tall! (Photo courtesy Colin D. MacLeod, UK.)
Can you find the baby in this line of Sperm whales? Is the biggest whale a male? Groups often spend surface time in a line like this, perhaps to communicate or search for danger. At other times they are very actively social, rolling around each other in a languid, three-dimensional ballet we've only become aware of with underwater photos and videos. Sperm whales make social clicks that scientists call "codas". Do codas just identify groups and individuals, or do they "say" something? Individuals probably track each other during dives by their unique click patterns, and intervals between clicks can tell scientists the length of the whale making the click. (Photo courtesy Colin D. MacLeod, UK.)
In spite of a terrible toll from whaling, sperm whales are probably the most abundant large whale. Their enormous heads efficiently control sound, and perhaps buoyancy. Only their small, narrow lower jaw has teeth, the ivory of whalers' scrimshaw. The mouth's edge is white, and may serve to attract prey at black depths, close enough for the short grooves on the whale's throats to help suck prey in. Makes sense, doesn't it? Why move a body with the mass of up to 60 tons when the food may swim close enough to be vacuumed up. Some squid are big enough to bite back, leaving scars, and the very biggest make the struggle life or death for the whale too. (Photo courtesy Colin D. MacLeod, UK.)
This sperm whale died when she caught a synthetic line while foraging perhaps over a thousand feet below the surface. She fought so hard to get free she broke her jaw, and the infection killed her. It also killed her unborn baby. We only knew this because her body floated ashore, or stranded. We learned many things from her death, except how to prevent it from ever happening again to another whale.
The sperm whale looks very different from all other cetaceans because he is specially designed for a life in all the world's oceans, routinely foraging for over an hour at depths that would crush a submarine. Perhaps the skin's wrinkles become smooth under pressure, or perhaps even his head becomes more wrinkled as he dives deeper. It's still beyond our abilities to find out, but many people are trying. Special recorders have been attached to sperm whales, and other species, to tell heartbeat, location, depth and frequency of dives, and in some cases measure how the whale moves. Some tags use suction cups, but fall off quickly. Others use prongs to penetrate the tissue and, while their batteries last, send their data to satellites, but some of these may never come off. If some tags hurt whales, is it worth the knowledge gained?
Why is the head of a sperm whale so enormous? It seems designed to help the whale reach frigid, black depths where he finds his food, and make the sophisticated and powerful echoes that help him find it. Sperm whales seem too big to chase smaller and more maneuverable squid. Perhaps his white mouth attracts squid and other prey with a faint glow in otherwise utter darkness. From what we know so far, when the prey comes close enough, the whale might make a powerful "bang" sound that stuns the prey, and then, aided by throat grooves for rapid expansion, sucks them in one by one.
You are looking into the eye of a creature whose brain is many times the size of yours, but he's only five years old. He is looking back, very aware, curious. What do we look and seem like to a sperm whale? What does he think of us? If only he could tell us of the things he already knows. To us the black depths of the ocean are another world. To him it's home. Scientists recorded this young whale making an incredible variety of sounds, not one of which they understood.