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Arctic vandals
Our robber dinghy was lying as flat as a pancake on the ice edgewith two four-inch rips in the aft pontoon. With at least 1,000 km ofHigh Arctic wilderness between us and the nearest human settlement,we weren't prepared for vandals. But the culprits hadn't come far.Instead of footprints in the ice, a wide, blurred hauling trail led fromthe dinghy to the water, a telltale sign that Odobenus rosrnarus, "thetoothwalker", had paid a visit.
Perhaps the walrus had mistaken the dinghy for a busty kin andhad wanted to socialise? A walms's welcome can be both rough andbrutal and, using their tusks, they literally establish a peckingorder on the beaches where they haul-out. A dinghy, unfortunately,cannot fight back.
Approaching the herd
We first landed at Sandoen in North-east GreenlandNational Park, where a small herd of walruses spent thesummer. We hoped that, eventually, one or two individualswould take us out (and down) to their favourite feedinggrounds4 for some underwater photography. Staying well backto start with, we gradually moved closer to the herd each day.The walruses quickly accepted us, and soon barely raised theirheads when we arrived.
We picked out two animals to watch. A juvenile and anolder "mate" of his, possibly his father or grandfather. Thejuvenile had smooth brown skin and tiny tusks, while Grandadhad a neck full of scars and long, straight tusks. The juvenilewas always interested in what we were up to, and loved tocheck out our underwater camera.
Dinner for two
Though extremely social animals on thebeach, walruses are loners when feeding.Our two were the exception, and we oftensaw them travelling and diving together.We soon saw for ourselves just what amonotonous feeding routine walruseshave. An average dive lasted five minutesfollowed by 70 seconds at the surface forup to a dozen deep breaths. This would berepeated over and over again, for hours andhours and days and days.
It's surprising that these enormousbeasts feed mostly on tiny mussels, requiringup to 6,000 every day. Occasionally they'llgo for something larger such as a ringed sealor an eider duck. We watched one walrusattack two chicks from below, surfacingbelly-up and mouth wide open.
An empty shore
One morning, we arrived at the beach atSandmen to find it abandoned. Leaning backin the sand we soon fell asleep to the soundsof arctic terns and Sabine's gulls. Loud grantsand splashes woke us. Our two walrus friendshad returned and were rubbing their backs inthe shallow water right in front of us. Theseindividuals had proved themselves to be twoof the most pleasant personalities, and it was aprivilege to get to know them.
Biology
Walruses are the second largest mammal inthe Arctic (Whales are the largest one). Adultmales may weigh between 1,200 and 1,500kg.Walruses are easily distinguished from other pinnipeds by their huge tusks, which are enlargedupper canine teeth, and these are used for display,signaling an individual's rank in the hierarchyand as weapons in fights with other walruses. Thetusks also aid in hauling out on slippery ice-floesand can be used as weapons against polar bearsand killer whales and for killing seals. Walruseshave also been known to attack kayaks and boats,and there are documented cases of people beingkilled.
Distribution
Walruses are only found in the Arctic.They prefer relatively shallow water,because they feed on invertebrates, primarilymolluscs, which occur on the sea floor up toa depth of about 80m. Two subspecies aregenerally recognised: the Pacific walrus andthe Atlantic walrus. Pacific walruses occurin the Bering Strait region, while Atlanticwalruses are distributed from the centralCanadian Arctic eastward to the Kara Sea ofwestern Siberia.
Exploitation
From the sixteenth until the early decadesof the twentieth century, Atlantic walruses werehunted intensively for their oil, tusk ivory andhides. As a result, by the mid-twentieth century,the aggregate population of the Atlantic walruswas reduced in nearly all areas and its rangehad shrunk substantially. Indeed, by the 1930s,the East Greenland walrus was on the vergeof extinction. But it has now been protectedsince 1951, and the population is thought to bearound 1,000.
Reproduction
Female walruses become sexually mature at aboutsix and males between seven and ten. Both sexescan live to about 40. In the mating season (Januaryto April), males emit a variety of underwater soundsconsisting of taps, knocks, pulses and bell-like sounds.This acoustic display, or courtship, attracts oestrusfemales. After a gestation period of about 15 months, asingle calf is born in late spring. Reproductive femalescan produce about one calf every third year. Mostcalves are weaned when they are two. A high degree ofmaternal care results in low natural mortality in calves.
Our robber dinghy was lying as flat as a pancake on the ice edgewith two four-inch rips in the aft pontoon. With at least 1,000 km ofHigh Arctic wilderness between us and the nearest human settlement,we weren't prepared for vandals. But the culprits hadn't come far.Instead of footprints in the ice, a wide, blurred hauling trail led fromthe dinghy to the water, a telltale sign that Odobenus rosrnarus, "thetoothwalker", had paid a visit.
Perhaps the walrus had mistaken the dinghy for a busty kin andhad wanted to socialise? A walms's welcome can be both rough andbrutal and, using their tusks, they literally establish a peckingorder on the beaches where they haul-out. A dinghy, unfortunately,cannot fight back.
Approaching the herd
We first landed at Sandoen in North-east GreenlandNational Park, where a small herd of walruses spent thesummer. We hoped that, eventually, one or two individualswould take us out (and down) to their favourite feedinggrounds4 for some underwater photography. Staying well backto start with, we gradually moved closer to the herd each day.The walruses quickly accepted us, and soon barely raised theirheads when we arrived.
We picked out two animals to watch. A juvenile and anolder "mate" of his, possibly his father or grandfather. Thejuvenile had smooth brown skin and tiny tusks, while Grandadhad a neck full of scars and long, straight tusks. The juvenilewas always interested in what we were up to, and loved tocheck out our underwater camera.
Dinner for two
Though extremely social animals on thebeach, walruses are loners when feeding.Our two were the exception, and we oftensaw them travelling and diving together.We soon saw for ourselves just what amonotonous feeding routine walruseshave. An average dive lasted five minutesfollowed by 70 seconds at the surface forup to a dozen deep breaths. This would berepeated over and over again, for hours andhours and days and days.
It's surprising that these enormousbeasts feed mostly on tiny mussels, requiringup to 6,000 every day. Occasionally they'llgo for something larger such as a ringed sealor an eider duck. We watched one walrusattack two chicks from below, surfacingbelly-up and mouth wide open.
An empty shore
One morning, we arrived at the beach atSandmen to find it abandoned. Leaning backin the sand we soon fell asleep to the soundsof arctic terns and Sabine's gulls. Loud grantsand splashes woke us. Our two walrus friendshad returned and were rubbing their backs inthe shallow water right in front of us. Theseindividuals had proved themselves to be twoof the most pleasant personalities, and it was aprivilege to get to know them.
Biology
Walruses are the second largest mammal inthe Arctic (Whales are the largest one). Adultmales may weigh between 1,200 and 1,500kg.Walruses are easily distinguished from other pinnipeds by their huge tusks, which are enlargedupper canine teeth, and these are used for display,signaling an individual's rank in the hierarchyand as weapons in fights with other walruses. Thetusks also aid in hauling out on slippery ice-floesand can be used as weapons against polar bearsand killer whales and for killing seals. Walruseshave also been known to attack kayaks and boats,and there are documented cases of people beingkilled.
Distribution
Walruses are only found in the Arctic.They prefer relatively shallow water,because they feed on invertebrates, primarilymolluscs, which occur on the sea floor up toa depth of about 80m. Two subspecies aregenerally recognised: the Pacific walrus andthe Atlantic walrus. Pacific walruses occurin the Bering Strait region, while Atlanticwalruses are distributed from the centralCanadian Arctic eastward to the Kara Sea ofwestern Siberia.
Exploitation
From the sixteenth until the early decadesof the twentieth century, Atlantic walruses werehunted intensively for their oil, tusk ivory andhides. As a result, by the mid-twentieth century,the aggregate population of the Atlantic walruswas reduced in nearly all areas and its rangehad shrunk substantially. Indeed, by the 1930s,the East Greenland walrus was on the vergeof extinction. But it has now been protectedsince 1951, and the population is thought to bearound 1,000.
Reproduction
Female walruses become sexually mature at aboutsix and males between seven and ten. Both sexescan live to about 40. In the mating season (Januaryto April), males emit a variety of underwater soundsconsisting of taps, knocks, pulses and bell-like sounds.This acoustic display, or courtship, attracts oestrusfemales. After a gestation period of about 15 months, asingle calf is born in late spring. Reproductive femalescan produce about one calf every third year. Mostcalves are weaned when they are two. A high degree ofmaternal care results in low natural mortality in calves.