Juvenile Penguins Go Beyond Safe Area
By LES LINE
satellite telemetry, scientists have tracked juvenile emperor penguins from
their natal colony at the
"It is disturbing to learn that emperor penguins leave the relative safety of the Ross Sea during at least one critical stage in their life cycle and range in areas that are, and will become, more heavily exploited by commercial fisheries," said Dr. Gerald L. Kooyman, a researcher at the Scripps Institute of Oceanography in San Diego.
Dr. Kooyman expressed concern that large numbers of the penguins could be caught in the nets or long lines of fishing fleets, and that stocks of the marine animals on which they feed could be overfished.
provisions of the Antarctic Treaty and the Convention on the Conservation of
Antarctic Marine Living Resources extend only to the 60th parallel in the
Dr. Kooyman said these findings suggested that the 60th
parallel was "too limiting to adequately protect even the most familiar
symbol of Antarctic wildlife, the emperor penguin." He urged that
scientists investigate the dispersal patterns of Adelie
and Chinstrap penguins, which also breed on the coast of
The satellite tracking of young emperor penguins, using small transmitters glued to the feathers on their backs, is part of a continuing study of the species by Scripps scientists. The Ross sea birds,Dr. Kooyman said, are of special interest because they occur in the last marine frontier that has not been exploited by humans .
The geography of the
The emperor is the world's largest penguin, standing nearly four feet tall and weighing as much as 90 pounds. Emperor penguins breed in the winter darkness after the sea ice forms, gathering in colonies either on the floes or the coast. The females lay a single egg each and then spend several weeks at sea while the incubating males fast and huddle for warmth in temperatures that hover around 40 degrees below zero. The parents reunite as the southern sky starts to lighten and the eggs hatch, and over the next five months they share the duty of raising the rapidly growing chicks.
The entire breeding cycle consumes nine months. The parent birds depart to put on weight and molt shortly before their chicks fledge, leaving the 25 pound juveniles to fend for themselves. Dr. Kooyman said the adult emperor penguins travel in ice-congested polar waters during the nonbreeding months, feeding on fish and squid at depths up to 1,500 feet. But the whereabouts of the juveniles and their food habits from the time they leave the colony until their return several years later are still a mystery.
Because transmitters and antennas were attached near the penguins'
tails to reduce drag, satellite reception was possible only when the birds were
out of the water, resting on pack ice or a drifting iceberg. The juvenile
emperors left the
Juvenile emperors, he added, are not as physiologically capable as the adults, and the availability of prey that can be caught in shallower dives "may be the key as to why they go so far north."
1,096 Mammal and 1,108 Bird Species Threatened By LES LINE
Since 1960, when it started a card file on 34 rare animals. the Species Survival Commission of the World Conservation Union has kept a rapidly growing list of threatened wildlife on every continent. The Red List, as it became known to conservationisits, was updated last week using revised criteria for determining the risk of extinction, and the news is grim: 1.096 mammals, nearly one fourth of all known species, are considered threatened, as are 1,108 birds, more than 11 percent of the world's bird species.
The number of mammals listed as critically endangered (169), endangered (315) or vulnerable (612) is startling, since this is the first time that the organization, formerly known as the International Union for the Conservation of Nature, has fully assessed the status of each of the 4,630 or so species in the world's 26 orders of mammals. In the past only birds, which number 9,670 species. have been evaluated on a comprehensive global scale.
three risk categories are based in large part on the rate of a species'
population decline over them last 10 years.
For example, animals whose numbers have dropped by 80 percent are
considered critically endangered. Habitat loss, fragmentation and degradation,
reflecting human population growth and economic development, were cited as
the most significant threats to Red List animals. But the Species Survival
Commission said the introduction of non-native species threatened entire
ecological communities, especially in aquatic systems and in isolated environments
a statement, interior Secretary Bruce Babbitt described the new Red List as
"probably the most thorough scientific assessment of the state of the
world's wildlife ever undertaken." Dr. Russell Mittermier,
a primate expert who is president of Conservation international in
And Dr. William Conway, directorof the Wildlife Conservation Society at the Bronx Zoo, said. "Few animals that lie in the path of human developnment and have limited ranges can bec exacted to survive without special efforts to protect them."
More than 500 scientists contributed to the evaluations which identity 5205 animals of all kinds as threatened.The document lists 253 reptile. 124 amphibian and 734 fish species as being at risk of extinction, but itemphasizes that thousands of species cies in those taxonomic groups have not been assessed. "It is impossible to make definitive statements about their overall conservation status," the report states. And 1,891 species of invertebrates, mainly crustaceans, insects and mollusks. are threatened, but very few of the so-called lower animals have been examined relative to their immense numbers.
Among the different orders of mammals.330 species of rodents. 231 bats. 152 shrews and moles. 653arnivores (cats. bears, raccoons, wild dogs and weasels). 96 primates and 70 even-toed ungulates (hippopotamuses, pigs, deer, antelope, goats and sheep) are listed as threatened. In the case of primates, nearly half the world's monkeys and apes are on
Red List, along with 11 of 18 species of hoofed mammals, a high profile group
that includes rhinoceroses, zebras, wild horses and tapirs.Among
little-known mammals listed ed as critically endangered.
The countries with the largest number of threatened