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Ano Nuevo has the only sizeable colony of the warm-blooded mammals on
the mainland. The rest breed on offshore islands.
The bulls, weighing up to three tonnes, fight as they jockey for space on the
sand and try to protect harems that can number hundreds of females.
Don Hillier, a volunteer guide, said visitors often set out hoping to get close
enough to touch the seals.
"They want to see them fight, but when it starts, they change their minds.
The fights are really very vicious and ferocious", he said. The combatants are
rarely killed, however.
The northern elephant seal, once hunted for blubber, was thought to be
extinct in the late 19th century, but a tiny colony of about 100 was discovered on
an island off the coast of Mexico in 1892.
They have made a spectacular comeback, doubling their population every
five years in the past two decades and they now breed in increasing numbers on
the mainland.
The world northern elephant seal population has grown to an estimated
70,000 and some scientists think there may be 100,000. (Southern elephant
seals, larger and more numerous, are found from Australia to South America and
Africa).
More than 200 pups were born at Ano Nuevo in the first four weeks of this
breeding season.
Hillier related how once he had a whole tour group in front of one harem of
female seals. "All of a sudden a woman asked me, what is that one doing?
"I turned around and the female seal was giving birth right in front of us.
Soon afterwards the seagulls started swooping down to get the afterbirth".
Scientists have been making some startling discoveries about the animals.
Don Costa, a marine biologist at the University of California at Santa Cruz,
said scientists only recently confirmed that the seals routinely dive to a depth of
2,300 feet (760 metres) to feed. Depth recorders strapped to the backs of females
show they dive up to 2,700 feet (900 metres).
Researchers have found that during active periods, such as the breeding
season, the seals fast. The adult males can lose up toa third, and females up to 45
per cent, of their mass.
In the warm-weather months, the seals migrate north as far as the Gulf of
Alaska. They return in mid-December to the islands off Mexico and California,
and now Ano Nuevo, to breed.
Signs posted along the highway warn: "Beware of elephant seals". Not bad
advice since the bulls can be larger than the family car.
Notes
elephant seal морской слон
bull бык, буйвол
blubber ворвань
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