Polar bears and bison are on the brink — can zoos help?
|August 28, 2009||Posted by Jeffery J. Smith under Progress Report, The Progress Report|
Polar bears and bison are on the brink — can zoos help?
Switzerland gains territory from Italy as glaciers in high Alps melt
All green issues point to territory or habitat. That problem points to the solution known as geonomics. We trim, blend, and append four 2009 articles from: (1) Associated Press, Aug 19, on a border shift; (2) BBC, Aug 4, on bison by Matt Walker; (3) BBC, Aug 25, on polar bears by Victoria Gill; and (4) BBC, Jan 8, on zoos by Tom Geoghegan.
by Associated Press, by M. Walker, by V. Gill, by T. Geoghegan
- Switzerland gains territory due to melting glaciers
Switzerland has expanded its border at Italy’s expense. Melting glaciers and snow fields in the high Alps moved the watershed which had determined the border since 1942.
The Italian embassy in Bern said the change has already been approved by Rome.
The shift moves the final stop of the Furggsattel Sesselbahn ski station near the famed Matterhorn peak onto Swiss territory.
JJS: Its not just Italians losing territory.
- European bison on ‘genetic brink’
The European bison remains extremely vulnerable to extinction, despite long-standing efforts to save it. At 3m long, 2m tall and weighing up to 900kg, the European bison (Bison bonasus) is Europe’s heaviest surviving land mammal.
Although one of the two remaining wild herds of pure bred European bison has steadily risen to around 800, its effective population size of just 25. The effective population of any group of animals is lower than the total number, due to factors such as non-breeding individuals or a skewed sex ratio.
Usually, a group must have an effective genetic population of 50 animals to be considered to be safe from an immediate extinction caused by inbreeding or having too few alleles to adapt to new environments.
Today’s population stands at around 1400 spread all over the world. It survives in the wild in just a few herds, the two largest of which live on either side of the Bialowieza forest which straddles Belarus and Poland.
While European bison can interbreed with American bison (Bison bison), they are generally considered to be separate species, having considerable genetic and morphological differences.
For hundreds of years, the European bison was protected across large parts of its European range, being considered ‘King’s game’ protected by the monarchy and Russian tsars that conquered Poland.
But early in the 20th Century, its numbers crashed as people left hungry by World War I and a lack of protection saw ruthless poaching of the animals for meat and hide. By 1919, none were left in the wild.
With just four bulls and three cows, biologists founded todays purebred population. Of those alive today, all originate from just from just one bull, with 90% of all their genes coming from two founders.
Without outsiders with fresh genes, all we can do is maintain a bison-friendly environment and widen it.
JJS: Widening habitat, thats a job for geonomics (see below).
- Stress’ is shrinking polar bears
Polar bears have shrunk over the last century. Scientists compared bear skulls from the early 20th Century with those from the latter half of the century. Their study, in the Journal of Zoology, linked the changes to an increase in pollution and the reduction in sea ice. Pollutants in the bears’ bodies, and the increased effort needed to find food, could limit the animals’ growth.
The team, which included colleagues from Aarhus University’s Department of Arctic Environment, also found shape differences. Dr Pertoldi explained that could be linked to pollutants that have built up in the Arctic and in the polar bears’ bodies.
The pollutants that the scientists focused on were compounds containing carbon and halogens — fluorine, chlorine, bromine or iodine. Some of these compounds have already been phased out, but many still have important uses in industry. These include solvents, pesticides, refrigerants, adhesives, and coatings.
“We also know from previous studies that some chlorinated chemical pollutants have affected the fertility of the females,” he continued.
Hunting over the last century, said Dr Pertoldi, could have depleted the gene pool, leaving polar bears to suffer the effects of inbreeding.
JJS: Can zoos save nearly extinct animals?
- What are zoos for?
A zoo in Germany has refused to help two polar bear cubs who were rejected by their mother and are now believed to have been eaten by her.
Professor Andrew Linzey, director of the Oxford Centre for Animal Ethics, says, “The creation of dependency involves direct duties. It’s implausible to argue that just because it happens in nature, we should allow it to happen in an environment where we have artificially made them dependent on us.”
Today’s zoos are no longer a showcase for exotic animals, rather places for conservation, education, and interaction.
But there’s a practical issue of space. While it may seem odd to let an animal within its care die, zoos consider what is best in the long-term.
Zoos make polar bears neurotic, says Daniel Turner of the Born Free Foundation. They pace up and down their enclosures, bobbing their heads and twisting their necks.
And two macaques at Newquay Zoo were put down because they were fighting, he says. Abroad, tigers have been known to fall into the hands of taxidermists.
Instead of putting animals in zoos, help preserve their natural habitat.
JJS: Habitat is key. Shrinking the human footprint happens when we implement geonomics — shift taxes and subsidies to penalize waste and reward efficient use of land and resources and the ecosystem in general.
Jeffery J. Smith runs the Forum on Geonomics.
Tiger attacks trigger expert plea
Wilderness in 34 Eastern States Open to Drilling
Elephants’ numbers grows; is more progress forthcoming?
What are your views? Share your opinions with The Progress Report!