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Five Days With Fat Hoods - hooded seals grow up fast

International Wildlife, Jan, 1999

In a race for survivial, newborn hooded seals gorge on the richest milk on Earth

A nursery of hooded seals is a risky, evanescent place: a white layer of drifting ice pushed by heavy winds of the northern seas. Storms buckle and break the floe, warmth melts it, currents shift it. On this battered platform, the key to survival is to grow up fast.

In this, the hooded seal is the world record holder: A pup gains, on average, 15 pounds each day, expanding visibly from birth to weaning in an explosion of growth that takes just four days. By day five, solicitous mothers have disappeared, and the pudgy youngster is left to tackle lifeOs trials on its own.

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In seal society, fat is fortune, and seals that whelp on the dangerous, fast-changing ice compress the vital period from pup birth to independence by imbibing great quantities of fat-rich milk. In an explosion from slim to obese, hooded seals more than double their birth weight and their girth in the shortest lactation period known for any mammal. To accomplish this, the pup drinks daily 17 to 20 pounds of the richest milk on Earth. This natural formula is the consistency of thick, viscous, oily, slightly peach-colored cream and contains the most dry matter (70 percent), fat (61 percent) and gross energy (5.9 calories per gram) reported for any mammal. It is about 18 times richer than cow's milk.

Hooded seals are not rare--their total population is estimated at 500,000--but they have been rarely studied for the simple reason that their pack-ice breeding areas are remote, hostile and mobile, in some places drifting 20 to 30 miles a day. In early March in Canada's Gulf of St. Lawrence between

Prince Edward Island and the Magdalen Islands, for instance, winds and currents usually push a major breeding population of about 7,000 adult hooded seals to the east where their icy platforms disappear, making short-term observation of their behavior a matter of luck.

But in the spring of 1997, strong winds in this region drove the hooded seal's ice against the Cape Breton Island coast, and there it got stuck. This presented a marvelous--and unusual--opportunity to study the same group of seals on a continuous basis and to observe what happens to pups whose lives are telescoped into such intense periods of growth. What follows is a day-by-day record of what I saw on five successive days ferrying in by helicopter to the same remote spot.

DAY 1: BIRTH ON ICE

The pack ice is a surreal Jackson Pollock world of white emptiness seamed and blotched by soot-black leads and pools of open water broken by jumbled ice blocks of pressure ridges. From high overhead, the hooded seals are easy to spot: dark spindle shapes upon the gleaming white. They lie in "family" groups: a female with her pup, often with a male or two in waiting.

Hooded seals are large, powerful and aggressive. The male is more than 8 feet long and weighs about 650 pounds; the female is 7 feet long and, prior to parturition, may weigh slightly more than 400 pounds. Both have smoky, blue-gray coats, dappled with irregular black blobs.

Sealers feared the "hoods," as they called hooded seals. In his classic account of sealing, Vikings Of The Ice, the American author George Allan England wrote in 1924: "Sealers tell many fearsome tales of men losing leg or arm to dog-hood bites."

We land near a lead, a rift of open water between the floes, with several families of hooded seals in the vicinity. One female has just given birth. Unlike most seal pups that are born fatless and shivery into a chilly world, the hooded seal pup arrives nicely wrapped in insulating blubber that makes up 19 percent of its birth weight of 48 pounds. This pup has already molted its woolly, grayish natal fur in utero, and it now has an elegant, short-haired fur coat: deep bluish gray above, shading into silvery gray and creamy white on sides and belly.

In her brief maternal life, the mother is passionately protective of her newborn. She snarls at me, eyes flashing, mouth agape and armed with lots of long sharp teeth. She charges, undulating across the ice, but I am at a respectful distance where, I know from long experience, the pull of pup will exceed her hostile impulse to tear the intruder to pieces.

At least I hope so.

Three yards from me she stops and turns abruptly. Her youngster is half an hour old. It butts its mother's flank, which means it wants to nurse. The female rolls onto her side and the pup begins to drink, switching frequently from teat to teat, eyes closed in blissful concentration. After ten minutes, it stops--its dark muzzle flecked with cream--rolls onto its back, mewls softly like a contented kitten, stretches, yawns and falls asleep.

Half an hour later the pup awakes, and the process repeats. I watch until evening, when I have to leave.

DAY 2: DRINKING LIKE CRAZY

Since its birth yesterday at 10 am "my" pup has gained 15 pounds. About 3 feet long at birth and fairly slim, the pup today looks shorter because it is fatter. It still drinks with rapt concentration at half-hour intervals. Sleep and drink, sleep and drink, and gain lots of weight:

Five Days With Fat Hoods - hooded seals grow up fast

International Wildlife, Jan, 1999

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