SYDNEY, Dec. 6 (Xinhua) -- Australia's use of rat poisons restricted in many other countries is behind the lethal toxins found in more than 70 percent of its smallest and most common owls, latest research has found.
The commercial rat poisons are "anti-coagulants that are very strong and chemically stable ... This means that when an owl or other predator consumes a rat or mouse that has fed on bait, they are consuming toxins that will stay in their system for a long time," a media release from Western Australia's Edith Cowan University on Wednesday quoted its researcher Michael Lohr as saying.
"The more they consume, the higher the toxic load in their liver, until they reach a fatal dose."
Lohr's work focused on the boobook owls but the "secondary poisoning also affects other animals, including cats, hawks and eagles", according to the university.
The boobook nocturnal bird of prey, measuring about the length of a dinner plate, can be found in almost all Australian landscapes, including urban areas.
Due to resistance, stronger versions of poison have been developed to kill rats more effectively with a single ingestion, said Lohr, whose work is expected to help with a review of second-generation pesticides in Australia.