Thursday, October 18, 2007

Endangered Wild Ox Given Lifeline


Source:

Science Daily — Twenty years after its discovery in the forested mountains of Vietnam, local authorities here have agreed to establish new nature reserves to protect a critically endangered wild ox.
As part of a plan to protect the saola (Pseudoryx nghetinhensis), the central Vietnamese provinces of Thua Thien Hue and Quang Nam will create two 121km2 reserves. The reserves will link up with the Bach Ma National Park to cover a continuous protected landscape covering approximately 2,920km2 — stretching from the Vietnamese coast to the Xe Sap National Biodiversity Conservation Area in neighbouring Laos.
“This secures a landscape corridor which is less vulnerable to the impacts of development, climate change and human pressure,” said Dr Barney Long, Central Truong Son Conservation Landscape Coordinator for WWF Vietnam.
“The saola population in Thue Thien Hue and Quang Nam provinces offers the best, if not the only, chance for this unique flagship species to survive.”
Found only in the Annamite Mountains of Vietnam and Laos, the saola was discovered in 1992 by a team of scientists from the Vietnamese Ministry of Forestry and WWF; the first large mammal to be discovered anywhere in the world since 1936.
The saola is a primitive member of the Bovidae family, which includes antelopes, buffalo, bison, cattle, goats and sheep. Although very little is known about the species, its global population is thought to be no more than 250 individuals, and its distribution highly restricted to only six provinces in Vietnam and four in Laos. The largest population is found in the far south of the saola's distribution range in Vietnam on the border between Thua Thien Hue and Quang Nam provinces where the nature reserves will be established.
Other species that will be protected by this enhanced green corridor include the Truongson muntjac, red-shanked douc and white-cheeked crested gibbon, as well as many other newly and yet to be described species.
Recently WWF announced the discovery of 11 new species of animals and plants in this remote area of Vietnam, including butterflies, orchids and a snake.
“The saola acts as an emblem of conservation efforts in Vietnam, yet it remains on the brink of extinction,” added Tran Minh Hien, WWF Vietnam’s Programme Director.
“We are committed to supporting local agencies to develop locally appropriate interventions to ensure its survival.”
Note: This story has been adapted from material provided by World Wildlife Fund.

Fausto Intilla

US-Russia Polar Bear Treaty Ratified


Source:

Science Daily — The US and Russia have ratified a bilateral agreement for the long-term conservation of shared polar bear populations in Alaska, the US and Chukotka, Russia.
The treaty unifies US and Russian management programmes that affect this shared population of bears. Notably, the treaty calls for the active involvement of native people and their organizations in future management programmes. It will also enhance such long-term joint efforts as conservation of ecosystems and important habitats, harvest allocations based on sustainability, collection of biological information, and increased consultation and cooperation with state, local, and private interests.
"WWF is pleased that this treaty will finally go into effect and formalize the increasing cooperation between US and Russian management agencies, scientists, and native communities in an effort to conserve our shared population of polar bears," said Margaret Williams, director of the WWF Bering Sea-Kamchatka Ecoregion Programme.
“With the rapid decline of arctic sea ice, now more than ever, we need to work together to ensure that polar bears have a chance to survive difficult times ahead."
Polar bears typically occur at low densities over vast areas of the Arctic. Current estimates of the world's 19 separate populations range from 20,000 to 25,000 bears. Two populations of the bears occur in Alaska: the southern Beaufort Sea population (about 1,500 animals), shared with Canada; and the Alaska-Chukotka (Chukchi Sea) population (approximately 2,000 bears), which is shared with Russia.
"While we are very pleased the treaty is coming into effect and support its goals, we urge the US government to take more courageous and bold actions to address the factor now widely recognised as the source of global climate change and resulting warming in the polar bears' arctic habitat: CO2 emissions," Williams added.
The treaty fulfills the spirit and intent of the 1973 multilateral Agreement on the Conservation of Polar Bears among the United States, Russia, Norway, Denmark (for Greenland) and Canada by allowing a sustainable harvest by Alaska and Chukotka natives, but prohibiting the harvest of females with cubs or of cubs less than one year old. It also prohibits the use of aircraft and large motorized vehicles in the taking of polar bears and enhances the conservation of specific habitats such as feeding, congregating, and denning areas.
Note: This story has been adapted from material provided by World Wildlife Fund.

Fausto Intilla

Thursday, October 4, 2007

No Faking It, Crocodile Tears Are Real


Source:

Science Daily — When someone feigns sadness they “cry crocodile tears,” a phrase that comes from an old myth that the animals cry while eating.
Now, a University of Florida researcher has concluded that crocodiles really do bawl while banqueting – but for physiological reasons rather than rascally reptilian remorse.
UF zoologist Kent Vliet observed and videotaped four captive caimans and three alligators, both close relatives of the crocodile, while eating on a spit of dry land at Florida’s St. Augustine Alligator Farm Zoological Park.
He found that five of the seven animals teared up as they tore into their food, with some of their eyes even frothing and bubbling.
“There are a lot of references in general literature to crocodiles feeding and crying, but it’s almost entirely anecdotal,” Vliet said. “And from the biological perspective there is quite a bit of confusion on the subject in the scientific literature, so we decided to take a closer look.”
Vliet said he began the project after a call from D. Malcolm Shaner, a consultant in neurology at Kaiser Permanente, West Los Angeles, and an associate clinical professor of neurology at the University of California, Los Angeles.
Shaner, who co-authored the research paper*, was investigating a relatively rare syndrome associated with human facial palsy that causes sufferers to cry while eating. For a presentation he planned to give at a conference of clinical neurologists, he wanted to know if physicians’ general term for the syndrome, crocodile tears, had any basis in biological fact.
Shaner and Vliet uncovered numerous references to crocodile tears in books published from hundreds of years ago to the present.
The term may have gained wide popularity as a result of a passage in one book, “The Voyage and Travel of Sir John Mandeville,” first published in 1400 and read widely, they write.
Says the passage, “In that country be a general plenty of crocodiles …These serpents slay men and they eat them weeping.”
Shaner and Vliet also found reference to crocodiles crying in scientific literature, but it was contradictory or confusing, to say the least.
One scientist, working early last century, decided to try to determine if the myth was true by rubbing onion and salt into crocodiles’ eyes. Shaner said. When they didn’t tear up, he wrongly concluded it was false. As Shaner said, “The problem with those experiments was that he did not examine them when they were eating. He just put onion and salt on their eyes.”
As a result, Vliet decided to do his own observations.
In the myth, crocodiles often cry while eating humans. However, deadpanned Shaner, “we were not able to feed a person to the crocodiles.”
Instead, Vliet had to settle for the dog biscuit-like alligator food that is the staple at the St. Augustine alligator farm. He decided to observe alligators and caimans, rather than crocodiles, because they are trained at the farm to feed on dry land. That’s critical to seeing the tearing because in water the animals’ eyes would be wet anyway.
The farm’s keepers don’t train the crocodiles to feed on land because they are so agile and aggressive, Vliet said. But he said he feels sure they would have the same reaction as alligators and caimans, because all are closely related crocodilians.
What causes the tears remains a bit of a mystery.
Vliet said he believes they may occur as a result of the animals hissing and huffing, a behavior that often accompanies feeding. Air forced through the sinuses may mix with tears in the crocodiles’ lacrimal, or tear, glands emptying into the eye.
But one thing is sure: faux grief is not a factor. “In my experience,” Vliet said, “when crocodiles take something into their mouth, they mean it.”
*A paper about the research appears in the latest edition of the journal BioScience.
Note: This story has been adapted from material provided by University of Florida.

Fausto Intilla

Biologists Close In On Mystery Of Sea Turtles' 'Lost Years'


Source:

Science Daily — Biologists have found a major clue in a 50-year-old mystery about what happens to green sea turtles after they crawl out of their sandy nests and vanish into the surf, only to reappear several years later relatively close to shore.
In a paper set to appear Wednesday in the online edition of the journal Biology Letters, three University of Florida sea turtle scientists say they found the clue by analyzing chemical elements ingrained in the turtles’ shells.
Their conclusion: The turtles spend their first three to five “lost years” in the open ocean, feeding on jellyfish and other creatures as carnivores. Only after this period do they move closer to shore and switch to a vegetarian diet of sea grass – the period in their lives when they have long been observed and studied.
“This has been a really intriguing and embarrassing problem for sea turtle biologists, because so many green turtle hatchlings enter the ocean, and we haven’t known where they go,” said Karen Bjorndal, a professor of zoology and director of UF’s Archie Carr Center for Sea Turtle Research. “Now, while I can’t go to a map and point at the spot, at least we know their habitats and diets, and that will guide us where to look.”
The discovery is important not only because it’s a first, but also because it may aid in conservation of the turtles -- which, like all sea turtles, are classified as endangered. “You can’t protect something,” said Bjorndal, “if you don’t know where it is.”
The paper’s lead author is Kimberly Reich, a UF doctoral student in zoology who did the work as part of her dissertation research. The other authors are Bjorndal and Alan Bolten, a faculty member in zoology and associate director of the sea turtle center.
Famed sea turtle biologist Archie Carr first discussed the mystery of the green sea turtles’ “lost years” in his 1952 book, “The Handbook of Turtles.” Half-dollar sized hatchlings trundle off subtropical and tropical beaches worldwide, then vanish, only to reappear, dinner-plate-sized, over continental shelves in depths of less than 650 feet. Only a tiny number of green turtles between the half-dollar and plate-sizes have ever been spotted.
To solve the problem, Reich, Bjorndal and Bolten turned not to scouring the ocean but rather to a technique that over the past two decades has become increasingly important in questions related to ecological origin: stable isotope analysis.
The higher an animal on the food chain, the more heavy isotopes it accumulates. As a result, the technique, which measures the ratios of heavy to light isotopes, can distinguish samples from herbivorous versus carnivorous creatures and where on the food chain they lie.
The researchers captured 44 turtles off a long-term study site near Great Inagua in the Bahamas. The sample included 28 that had been tagged in previous years, indicating they were residents of the site, and 16 untagged turtles assumed to have recently arrived.
They cut off tiny pieces near the center of the turtles’ shells in a harmless process that Bjorndal likened to trimming one’s fingernails. The biologists used a mass spectrometer, a machine that separates isotopes according to charge and mass, to analyze the oldest, or earliest-grown, portions of the shell sample versus the newest portions.
The analysis revealed that with the new arrivals to the site, the ratio of light to heavy nitrogen isotopes in the older versus new shell samples was “significantly different,” as the paper said. The ratios were very similar to ratios observed in oceanic-stage loggerhead turtles known to be carnivorous. For these reasons, among others, the researchers concluded the turtles spend their first three to five years in the open ocean.
Green turtles nest on subtropical and tropical beaches worldwide. That suggests the young turtles are widely distributed in the oceans during their oceanic stage, but Bjorndal said further study is required to confirm that.
Green turtles are the ocean’s largest hard-shelled turtle, with only soft-shelled leatherbacks eclipsing their size. They were heavily exploited for food by native peoples and then by explorers and colonists who prized the animals for remaining alive and fresh for months on ships. Although they were among the first animals listed under the Endangered Species Act in 1973, they and their eggs continue to be hunted in much of their range today.
Said Bjorndal, “Anything that helps us discover geographically where they are is going to stand us in good stead to be able to protect them.”
Note: This story has been adapted from material provided by University of Florida.

Fausto Intilla

Sea Otter, Peregrine Falcon Back From The Brink Of Extinction But Other Species At Risk In Canada


Source:

Science Daily — There’s good news and bad news in the report the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) just dropped on the Minister of the Environment’s desk.
The good news: The peregrine falcon and the sea otter no longer face extinction.
The not-so-good news: COSEWIC proposes adding another 36 species to Canada’s official List of Wildlife Species at Risk. Species from all regions of the country, on the land and in the sea, are at risk of extinction.
“Our job is to assess species based on the best available scientific, community and aboriginal traditional knowledge available,” says Jeffrey Hutchings. The Dalhousie biology professor has served as the chair of the committee for more than a year. “What we don’t take into account are the political or socio-economic consequences of our assessments.”
COSEWIC is a national scientific advisory body that assesses the status of wild species, subspecies, varieties, or other important units of biological diversity, that are considered to be at risk in Canada. As an arm’s length body, COSEWIC reports annually to the Minister of the Environment, who can accept the body’s recommendations, reject them or send species back to COSEWIC for further evaluation.
The peregrine falcon was almost wiped out in the 1950s and ‘60s because of pesticide contamination that thinned their eggshells. But since the 1970s, particularly after DDT was banned in Canada, this impressive bird of prey has made a strong recovery.
The resurgence of the sea otter — its rich brown pelt was once prized the world over — is even more dramatic. Extirpated on Canada’s west coast because of the fur trade more than a century ago, sea otters from California were reintroduced to British Columbia in the early 1970s. They’ve since repopulated a third of their historic range along the province’s coastline, and although numbers are still small, the population is healthy and expanding.
"It’s very satisfying to witness the successful recovery of species that were on the edge of extinction. It highlights the importance of endangered species legislation and associated recovery programs in protecting and recovering Canada’s wildlife," says Dr. Hutchings.
If only that legislation could help species like the basking shark, a plankton-feeding fish that grows to the size of a bus; the Eastern pond mussel, decimated by the introduction of the zebra mussel into the Great Lakes; and the Eastern flowering dogwood, one of Canada’s showiest trees which is being destroyed by an invasive species of fungus.
“Habitat loss and disturbance are the biggest threats facing species. This could be the result of factors as diverse as forestry, housing development, or changes to the natural flow of rivers,” says Dr. Hutchings. “Another major threat is the invasion of exotics that can have devastating effects on Canada’s native species.”
“Habitat loss and disturbance are the biggest threats facing species. This could be the result of factors as diverse as forestry, housing development, or changes to the natural flow of rivers,” says Dr. Hutchings. “Another major threat is the invasion of exotics that can have devastating effects on Canada’s native species.”
The legal list has expanded to include 389 species, which are categorized as extirpated, endangered, threatened or special concern.
Note: This story has been adapted from material provided by Dalhousie University.

Fausto Intilla