Signs of coordinated travel

WINDOWS into the most intimate cor­rs of whales’ lives have given us new in­sight into their courtship and mating strategies. In behavior seldom if ever witnessed, a male humpback at left appears to blow bubbles that will rise be­neath the genitals of a female, center, accompanied by her calf. Is this a stimulation to mate? No one knows. Such gentleness contrasts with often fierce competi­tion  among males for a female.

 

Right whale males, however, show less aggression toward their rivals and sometimes even appear to cooperate in mating with the same female. Off Pen­insula Valdes a male, at right, mates with a female as a second male waits his turn, left background. In another mating group a calf following its mother too closely is accidentally pounded by her massive flukes—a rare mishap since right whale females with calves usually avoid courting males. Its back also scuffed, an­other calf rests near its mother as she appears to mate.

 

Rather than by physical dom­inance, male right whales may pass on their genes by means of sperm competition. In theory, when numerous males mate with the same female, the male with the largest testes could dis­place or dilute the sperm of his rivals. And right whale males, with one-ton testes, have the highest testes-to-body-weight ratio of any baleen whale.

 

Right whale females calve only once every three years. In austral winter the tiny newborns keep in constant motion beside their mothers for their first month. A two- to three-month play stage follows; some exas­perated mothers roll over and hold their young between their flippers to quiet them. In No­vember mother and calf show signs of coordinated travel be­fore departing for the open At­lantic . . . we know not where.

 

DAPPLED by Arctic sun, inquisitive belugas loll in Lancaster Sound. Each summer these white whales swim through open leads (below) into traditional bays and inlets. Studying the effects of shipping noise on belugas and other Arc­tic whales, Larry Dueck of Can­ada’s Department of Fisheries and Oceans tape-records his ob­servations; he keeps a shotgun handy against polar bears.

 

More than 10,000 belugas in­habit the Lancaster Sound re­gion, although many more range above and below the Arctic Cir­cle. Belugas’ diet is as varied as their habitats and includes arctic cod, marine worms, bivalves, whelks, crustaceans, flatfish, salmon, char, and squid.

 

For their incredible voices, sailors called them “sea canar­ies.” Their repertoire includes chirps, croaks, burps, grunts, squeaks, moos, mews, screams, and yaps, and has been likened to a horse’s whinny, a baby’s cry, a rusty hinge, a bell, and a lecher’s whistle.

Lancaster Sound re­gion

Belugas mate in spring, and after a gestation of about 14 months, most calves are born in summer. The warmer water may make life easier for the brownish gray newborns, which are wrapped in only about an inch of fat in contrast to adults’ average of six to eight inches, more than a third of their weight.

 

A separate population of about 450 belugas in the St. Lawrence estuary is in trouble, with whales dying of cancer and other diseases that may be caused by pollution. Canadian researcher Pierre Beland and veterinary pathologist Daniel Martineau, financially supported by loans, examined stranded belugas and found a horrible ar­ray of bladder cancer, ulcers, tu­mors, and high levels of toxic chemicals such as PCBs and DDT. Regional industrial and agricultural practices are sus­pected, but the situation re­mains unresolved.  Check online for the best student loan forgiveness.