Our research has focused on southern right whale anatomy, acoustics, and population changes, as well as behavior.
One of the things that convinced me right whales were ideal for study is that, alone among all whales, they are adorned with series of peculiar growths called callosities (following pages and 334-5). On every right whale the number, size, shape, and placement of callosities are unique, making it possible for us—and presumably the whales too to tell individuals apart on sight.
Callosities consist of thickened white skin, sometimes many inches deep, with a rough outer surface. The rough surface offers excellent anchorage for creatures such as whale lice, barnacles, and smaller organisms, which hitch a ride on the whale and perhaps feed on what spills from its mouth or on bits of dead skin flaking off.
The largest callosity appears as if perched on the whale’s head. The old whalers called it the “bonnet,” and indeed from some angles it does look somewhat like a 19th-century lady’s headgear (above). To the old-timers this was the “right” whale to hunt because it swims slowly, has an unusually rich store of baleen, or whalebone, and floats when dead.
In our studies of callosities we discovered an interesting parallel with human beings. Callosities have scattered hairs growing from them. Curiously, right whales’ facial hair grows in the same places that a human’s does, and only in those places. The whales appear to have what we call mustaches, as well as eyebrows, beards, and even sideburns!
Callosities seem to serve several functions. One of them is to act as a sort of splash de-flector, preventing water from entering the whale’s blowhole. Other species of whales also have splash-deflecting structures, but these are usually fairings, or ridges, around the blowhole, quite different in character from the callosities of right whales.
In aggressive situations callosities may have another use. Right whales sometimes rub their heads across a competitor’s flank or back. Since a whale’s skin is very soft, even the slightest brush from a crusty callosity could be painful.
Several of our right whales have white spots on their backs that, in addition to callosities, help us keep track of individuals. Y-Spot—or Adele, as we later called her—had a calf in 1971 and then vanished for two years. I thought she had died, but she returned in 1974 with a new calf. To us it was a wonderful reunion. It also taught us that the adult’s callosity patterns are constant over long periods and that some females may breed only once every three years.
Such a low birthrate would help to explain the very slow recovery of one of the rarest whale species from two centuries or more of intensive hunting. From a population running to tens of thousands in the past, the southern right whale today numbers perhaps fewer than 1,500 individuals.