An increasing
number of raptors are exposed and dying from rodenticides, commonly called “rat
poison”. Unsuspecting people that wish to control or rid their property of
rodents often turn to products, such as D-Con; however, this choice comes at a high
price. When the targeted animal eats the poisoned bait, it does not die
immediately. This potentially deadly prey animal now runs the risk of being
caught and eaten by a non-targeted animal such as a raptor. Raptors that do
well in an urban environment, such as Red-tailed Hawks (Buteo jamaicensis) and owls, are at a higher risk.
Companies that manufacture
rodenticides try to counteract a bad public image by marketing the product as safe
and that the poisoning of non-target animals is rare. Below is a direct response
from D-Con’s website to the question of whether the product could poison
unintended animals: (http://www.d-conproducts.com/faq/)
The potential of any secondary poisoning
depends on what type of pet it is, how big it is, what type of bait it has consumed,
as well as how much bait was consumed. If you are concerned about a possible
exposure, you may wish to contact your veterinarian or the toll free number
located on the package to be directed to appropriate personnel who can address
your concerns. Occurrences of this type of poisoning are extremely rare.
They admit
that smaller animals are at greater risk. An adult Red-tail weighs two to four
pounds and an adult Great Horned Owl (Bubo
virginianus) two to three pounds. The preferred prey for these species are small
mammals, such as mice and chipmunks, are high targets for rat poison.
Anticoagulant
rodenticides (AR) affect the vitamin K-mediated synthesis of blood clotting
factors in the liver. The animal eats the poisoned prey and becomes at risk for
fatal hemorrhage episode triggered by trauma and/or increased heart rate.
Second generation anticoagulant rodenticides (SGAR) stay in the body longer
than its first generation, making it more lethal (Stone et al. 2003).
A recent study
revealed a high percentage of Red-tails and Great Horned Owl have residual
levels of rodenticides stored in their liver (Stansley et
al. 2014). The researchers collected liver
samples from Red-tailed Hawks and Great Horned Owls in New Jersey. At least one
SGAR was detected in 81 % of Red-tailed Hawks and 82 % of Great Horned Owls.
The most frequently detected SGAR was brodifacoum, which was detected in 76 %
of red-tailed hawks and 73 % of great horned owls. According to ((ABC) 2013)Brodifacoum was made a
“restricted use” pesticide in 2008 by EPA, meaning it can only be used by
certified pesticide applicators. The manufacturer of D-Con (household
brodifacoum) is challenging this decision in court. The product remains on the
market for public use.
Reading
between the numbers and statistics, rat poison remains a very real
danger for raptors. The bottom line, don’t use them! If you have a rodent
problem, put up a barn owl or kestrel nest box on your property. Please visit
these websites for information:
