The lead author for the following item - Alejandro Rodríguez - can be
contacted via
Behavioural and environmental correlates of soaring-bird mortality at
on-shore wind turbines
LUIS BARRIOS* and ALEJANDRO RODRÍGUEZ†
Journal of Applied Ecology 2004, 41, 72–81
Summary
1. Wind power plants represent a risk of bird mortality, but the
effects are still poorly quantified. We measured bird mortality,
analysed the factors that led birds to fly close to turbines, and
proposed mitigation measures at two wind farms installed in the Straits
of Gibraltar, one of the most important migration bottlenecks between
Europe and Africa.
2. Bird corpses were surveyed along turbine lines and an associated
power line to estimate mortality rates. The behaviour of birds observed
within 250 m of turbines was also recorded as a putative indicator of
risk. The effects of location, weather and flight behaviour on risk
situations (passes within 5 m of turbines) were analysed using
generalized linear modelling (GLM).
3. Mortality caused by turbines was higher than that caused by the
power line. Losses involved mainly resident species, mostly griffon
vultures Gyps fulvus (0·15 individuals turbine-1 year-1) and common
kestrels Falco tinnunculus (0·19 individuals turbine-1 year-1).
Mortalities were not associated with either structural attributes of
wind farms or visibility.
4. Vulture collisions occurred in autumn–winter and were aggregated at
two turbine lines where risks of collisions were greatest. The absence
of thermals in winter forced vultures to use slopes for lift, the most
likely mechanism influencing both their exposure to turbines and
mortality.
5. Kestrel deaths occurred during the annual peak of abundance in
summer. Carcasses were concentrated in the open habitats around a
single wind farm and risk may have resulted from hunting habitat
preferences.
6.Synthesis and applications. We conclude that bird vulnerability and
mortality at wind power facilities reflect a combination of
site-specific (wind–relief interaction), species specific and seasonal
factors. Despite the large number of migrating birds in the study
area, most follow routes that are displaced from the facilities.
Consequently, only a small fraction of birds on migratory flights was
actually exposed to turbines. New wind installations must be preceded
by detailed behavioural observation of soaring birds as well as careful
mapping of migration routes.
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http://www.nytimes.com/2004/03/23/science/23BIRD.html
In the Land of Kiwis, the Winged Variety Is Disappearing
By JANE E. BRODY
SOUTH ISLAND, New Zealand — This country evolved as a land of birds,
not mammals, and scientists and citizens are struggling to save
several of the more spectacular winged species unique to this area,
including the endangered royal albatross and two flightless species,
the yellow-eyed penguin and the kiwi, which gave its name to the
human residents.
"We call ourselves kiwis, but most New Zealanders haven't seen one in
the last 40 years," Paul Jansen, who coordinates the kiwi recovery
effort, said in an interview.
Of 93 species of birds native to New Zealand, only 50 remain, said
Lyndon Perriman, head ranger at Taiaroa Head in Dunedin, in the
southeastern part of the island, "and 37 of these are classified as
threatened or, worse yet, endangered."
<snip>
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http://www.nature.com/nsu/040322/040322-2.html
Oil-drenched birds get dry cleaned
Iron dust and magnets might save slick-stricken feathers.
23 March 2004
HELEN R. PILCHER
Soapy baths could become a thing of the past for birds caught in an oil
spill. Cleaning their feathers with iron powder and magnets instead
could be kinder both to the birds and the environment, say researchers.
The technique calls for spraying oil-laden birds with fine iron dust.
The particles soak up the sticky mess, and can then be stripped away
with powerful magnets.
This removes up to 98% of contaminants from dead mallard ducks ( Anas
platyrhynchos ) and little penguins ( Eudyptula minor ), report John
Orbell from Victoria University, Melbourne, Australia and colleagues in
Marine Pollution Bulletin 1.
This is not yet good enough to be used on live birds. But the team
hopes the method can be improved. They also aim to create a portable
device that could clean birds on the beach.
After a big spill, volunteers use detergents to clean thousands of
oil-laden sea birds. But this can take up to an hour for each bird, and
is stressful for the animals, says oil-spill relief expert Paul Kelway
from the International Fund for Animal Welfare. "Any method that speeds
things up and lowers bird stress is a good thing," he says.
Iron powder is cheap, easy to obtain and non-toxic. The main
alternative, phosphate-based detergents, can pollute water and feed
toxic algae blooms. "We're always looking for more environmentally
friendly detergents and other new cleaning methods," says Kelway.
Sitting ducks
Orbell's team tested their magnetic cleaning technique on individual
feathers a few years ago. They have now moved on to test the method on
dead birds. They poured oil on dead ducks from a market, and penguins
from a local nature reserve.
After 15 minutes of soaking, oily spots on the birds are dusted with
iron powder. Electrostatic forces cause the oil and iron particles to
stick together. The magnet then pulls the sticky mix away so it can be
recycled.
After 9 rounds of treatment, the birds are as clean as they're going to
get, says Orbell. But the small amounts of oil left behind damage the
feathers' waterproofing. "This isn't good enough," he says. If water
seeps in, birds lose their insulation and can die of hypothermia.
Smaller, rougher magnetic particles full of tiny perforations should
help the oil and iron stick together and strip away all the pollution,
the team thinks.
"Any method that can be deployed quickly and where large numbers of
people can work together without causing distress to the birds sounds
like a good thing," says Grahame Madge, spokesperson for the UK's Royal
Society for the Protection of Birds.
The magnets are unlikely to harm birds, says Orbell. Some birds have
tiny particles of iron oxide in their beak, which are thought to help
them navigate by the Earth's magnetic field. But Orbell says his
magnets are swept over the birds' bodies, not their beaks, so this
shouldn't interfere with navigation.
References
Orbell, J. D. et al .Marine Pollution Bulletin ,48, 336 -340 ,
doi:10.1016/j.marpolbul.2003.08.012 (2004).
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