Native Wildlife & Rodenticides: A Deadly Combination

Commercial rodenticides contain an anti-coagulant rodenticide called brodifacoum, it is an effective poison that unfortunately causes accidental secondary poisoning when native wildlife consume rodents that have been poisoned. Pets off course are also at risk. According to the APCC’s Dr. Steve Hansen, Senior Vice President, “If a pet ingests a rodenticide, potentially serious or even life-threatening problems can result, which may include bleeding, seizures, or damage to the kidneys or other vital organs”.
Rodents are an important link in the food chain for many species of wildlife such as hawks, owls and snakes.
There are native rat species that belong in our environment, such as the Bush Rat, Rattus fuscipes assimilis. Our native rodents should never be poisoned as they are the favoured prey and vital food source of many of our endangered Owls and Raptors in general.

WIRES have over the years received many possums poisoned by rat baits, even a young Pademelon having been poisoned by rat bait.

Consider that poisoning rodents destroys the natural balance and can make rodent problems much worse. If you are seeing rats/mice outdoors – consider the philosophy of Live and Let Live…Exclusion and sanitation are the most effective means of solving a rodent problem in or around the home.

If you have a rodent problem, try non-chemical methods first. The key aspects are:

Remove piles of yard debris, garbage, construction waste, etc. where rats or mice may make their nest.

Eliminate food sources. Don’t leave pet food outside. Keep wild birdseed and other food sources rats or mice may eat (such as some organic fertilizers) in rodent-proof containers. Collect and remove fallen fruit from fruit trees in the yard. Cover garbage bins, compost bins tightly.

Exclude rodents from your home. Seal cracks and openings in building foundations, and any openings for water pipes, electric wires, sewer pipes, drain spouts, and vents. No hole larger than ¼” should be left unsealed to exclude both rats and house mice. Make sure doors, windows and screens fit tightly. Their edges can be covered with sheet metal if gnawing is a problem. Install door sweeps at entry doors and garage doors – this will also help keep insects out. Course steel wool, wire screen and lightweight sheet metal are excellent materials for plugging gaps and holes. Plastic sheeting, wood caulking, and other less sturdy materials are likely to be gnawed away. – Source: Pest Notes, University of California, Agricultural and Natural Resources, Publication 74106, January 2003.

The three critical elements to keep rodents out of your home or other buildings: sanitation, exclusion, and population control. If the first two elements are not practiced, and an infestation occurs then population control must occur. Practicing good sanitation and the principles of exclusion potentially avoids having to deal with the difficult issues surrounding population control (traps, rodenticides, etc.).

The most successful way to keep rats and mice out of your home or other buildings is by exclusion and removing food sources. Poisons and traps are quick fixes that will have to be done continuously. Exclusion is more work but it’s a permanent solution. Poison can also cause the rats or mice to die in walls resulting in terrible smells.

Consider using traps, such as a snap- trap baited with peanut butter, this is the most humane, reusable dispatch of rodents with no harm to the environment, your pets, or your family. NEVER use any poisons or traps outdoors as other animals are likely to be harmed or killed by them. Finally, please don’t use cruel glue traps! No animal including mice should be subjected to such cruelty.

DO NOT FEED WILDLIFE – it is not in the best interest of our native wildlife and will attract animals you don’t want, like mice and rats.

Mice and rats can never be completely eradicated from our environment, and indeed if they were, entire populations of predators, such as birds of prey, snakes etc. would be gravely affected. Without the natural predators, populations of rats and mice would explode and defeat our best efforts at control. We must strive not to inadvertently poison our beneficial predators, and our household pets, by using rat poisons, especially outdoors.

Any use of poison indoors presents a grave risk to children and pets.

Reference : The Hungry Owl Project Raptors & Rodenticides: A Deadly Combination

ASPCA Pet poison alert: Rat and mouse poisons