Anticoagulant rodenticides are the most commonly used group of poisons to control rodents. Anticoagulant rodenticides have a delayed effect and animals that have received a lethal dose will die from haemorrhages after 6-10 days. Predators are therefore particular at risk from secondary poisoning when they predate on poisoned rodents. The cause for this high occurrence of secondary rodenticides poisoning of predators in Denmark is unknown, but may relate to the high density of buildings in rural landscapes and a systematic control of rodents – particular rats – in and around rural buildings.
Department of Environmental Science is researching in the presence of rodenticides in the environment and their effects in non-target animals in close collaboration with Bioscience.