Advertisement Picture


Advertisement Picture






Birdwatch News Archive


It seems all pesticides have some kind of ecological 'knock-on' effect, as American Kestrels are now finding out. Photo: Steve Hillebrand (commons.wikimedia.org)
It seems all pesticides have some kind of ecological 'knock-on' effect, as American Kestrels are now finding out. Photo: Steve Hillebrand (commons.wikimedia.org)Enlarge image

American raptor poison fears


Posted on: 14 Mar 2011

An unrestricted new pesticide has been shown to kill birds of prey in America, reviving bad memories of the DDT crisis in the 1960s.

New research on American Kestrels has shown that the rodenticide diphacinone - widely used as a substitute for rodenticides now banned or restricted by state law - shows significant build-up in the birds of prey at the top of the food chain, resulting in rapid fatalities.

American Kestrels that ingested more than 300 mg per kg of body weight died within 23 hours; others consuming a dose of 118 mg per kg also died, lasting no more than 47 hours. Lower doses resulted in survival. It is not known if the rodenticide affects breeding success like DDT, but any dose greater than 79 mg/kg appears to be eventually lethal for the small raptors.

The poison is developed to be tasteless and have a delayed action, which means that the live-prey eating kestrels are highly likely to eat contaminated mice and rats, as they will still be active after eating poisoned bait. Diphacinone is an anticoagulant which causes profuse unstoppable bleeding. Recovered kestrel corpses showed evidence of internal bleeding, though haemorrhaging was present even at non-lethal doses.

Using American Kestrel as surrogates for less common raptors, the study showed that protection limits for birds of prey need to be lower than the gamebirds previously used a surrogates. Rodenticides have also been found to be present in French, British and Canadian birds of prey, with possibly derogatory effects on populations exposed to the chemicals.

Reference: Rattner, B, Horak, K, Warner, S, Day, D, Meteyer, C, Volker, S, Eisemann, J, and Johnston, J. 2011. Acute Toxicity, Histopathology, and Coagulopathy in American Kestrels (Falco sparverius) Following Administration of the Rodenticide Diphacinone. Environmental Toxicology and Chemistry DOI:10.1002/etc.490

 




Your Comments

Tell us what you think...

You must be logged in to leave a comment. You can log in here.
If you don't have a user account please register.

Other News

RSPB Scotland supports offshore floating wind project

Posted: 04 Dec 2016
The RSPB has expressed its support for a floating wind energy generation project off the north coast of Scotland.

Read more…


Threatened shearwater colony devastated by New Zealand earthquake

Posted: 03 Dec 2016
An earthquake which struck New Zealand's South Island on 14 November has devastated the larger of the world's two remaining Hutton's Shearwater colonies.

Read more…


Prestigious award for BirdLife's Cambodia Programme

Posted: 02 Dec 2016
BirdLife’s Cambodia Programme, which has saved several Critically Endangered species from extinction, has received a prestigious award from the country’s government.

Read more…


Icelandic Eurasian Whimbrels fly non-stop to Africa

Posted: 01 Dec 2016
Research has revealed that Eurasian Whimbrels which breed in Iceland perform a rapid non-stop migration to and from their wintering grounds in West Africa.

Read more…


RSPB Scotland welcomes beaver reintroduction

Posted: 30 Nov 2016
RSPB Scotland has welcomed the Scottish Government’s decision to reclassify European Beaver as a native species to Scotland.

Read more…


  2 3 4 >