[Mike]

Hi SAD members,
What complete bs ~ polution.
again sorry if I’m being redundant.
Bridget
— In pac-pc@yahoogroups.com, Rocky Ward <rachelleward> wrote:
“Pollution” my ***.
~Rocky

Pollution Triggers Bizarre
Behaviour In Animals
By Andy Coghlan
NewScientist.com
9-8-4

Hyperactive fish, stupid frogs, fearless mice and seagulls that fall
over. It sounds like a weird animal circus, but this is no freak
show. Animals around the world are increasingly behaving in bizarre
ways, and the cause is environmental pollution.

The chemicals to blame are known as endocrine disruptors, and range
from heavy metals such as lead to polychlorinated biphenyls (PCBs)
and additives such as bisphenol A.

For decades, biologists have known that these chemicals can alter
the behaviour of wild animals. And in recent years it has become
clear that pollutants can cause gender-bending effects by altering
animals’ physiology, particularly their sexual organs.

But now two major reviews have revealed that the chemicals are
having a much greater impact on animal behaviour than anyone
suspected. Low concentrations of these pollutants are changing both
the social and mating behaviours of a raft of species. This
potentially poses a far greater threat to survival than, for
example, falling sperm counts caused by higher chemical
concentrations.

Snails and quails

The two research teams have independently collected evidence
revealing the effects on egrets and gulls, snails, quails, rats and
macaques, minnows, mosquito fish, falcons and frogs. Behaviours
altered include mating and parenting, nest building, learning,
predator avoidance, foraging, activity levels and even balance.

In one study, for instance, male starlings exposed to dicrotophos
insecticide decreased their singing, displaying, flying and foraging
activities by 50%. And newts exposed to low levels of the pesticide
endosulfan found it harder to sniff out the attractive pheromones of
potential mates.

Researchers have also shown that increasing numbers of male western
gulls hatched from eggs exposed to DDT attempt to mate with each
other. In recent years, scientists have also found that lead affects
the balance of gulls, while atrazine makes goldfish hyperactive and
the chemical TCDD makes the play behaviour in macaques rougher.

Despite this wealth of evidence, these effects have gone largely
unnoticed by toxicologists, says Ethan Clotfelter of Amherst College
in Massachusetts, lead author of one of the reviews, published in
August 2004 in Animal Behaviour (vol 68, p 465).

Missing a trick

Not only are we failing to acknowledge the scale of the problem
caused by endocrine disruptors, but toxicologists may be missing a
trick: changes in animal behaviour could be an early warning that
certain chemicals are harmful. “You might see behavioural effects
long before you see a population crash,” Clotfelter says.

Dustin Penn and Sarah Zala of the Konrad Lorenz Institute of
Comparative Ethology at the Austrian Academy of Sciences in Vienna
agree. They have just published a second review of the effects of
endocrine disruptors in the same journal (DOI:
10.1016/j.anbehav.2004.01.005). “The most important point is the
incredible amount of evidence that this is a widespread problem,”
Penn says.

Both research groups say that biologists must wake up to the fact
that endocrine disruptors might explain bizarre behaviour in wild
animals. And both reviews reveal that different concentrations of
chemicals can have unexpected effects.

Male mice exposed to low doses of some pesticides increase their
scent-marking behaviour, for instance, but decrease it when exposed
to higher concentrations.

Damaging doses

“Pollutants that have been considered safe when tested at medium
doses could have damaging effects at lower doses,” Penn and Zala
warn in their review. And conversely, toxicologists might exaggerate
the risks posed by higher doses.

Other behavioural biologists back the authors’ call for biologists
and toxicologists to work more closely to determine the scale of the
problem. “It’s been decades since the first evidence appeared that
chemicals in the environment can influence behaviour,” says John
McCarty of the University of Nebraska in Omaha, who researches the
impact of pollutants on birds.

“It seems to me that this body of evidence was pushed to the
background while most environmental scientists and regulators
focused on mortality and cancer rates [caused by endocrine
disruptors and other pollutants].”

The US Environmental Protection Agency says it cannot provide a
detailed comment on the research, but promises it will investigate
further. “We’ll review these two scientific articles as we continue
to develop an endocrine screening and testing programme,” a
spokeswoman told New Scientist.

Geoff Brighty, ecosytems science manager at the UK Environment
Agency, agrees that studying the effects of chemicals on animal
behaviour should be given a higher priority. “It is becoming
recognised that behaviour is important to look at to make sure a
chemical is safe, and we ignore it at our peril.”

© Copyright Reed Business Information Ltd.
http://www.newscientist.com/news/news.jsp?id=ns99996343