Here’s some good news I’m celebrating. To promote a healthier environment and enhance public education, the town’s Environment and Open Space Committee has taken a bold step and declared Poison-Free Woodside. Many residents already seek pesticide free approaches, but this effort will help to assure that everyone understands and can comply. I feel blessed to live in a town with deeper than average awareness of environmental issues and the will to always do better.
As I previously shared in the piece What Can We Learn from P-22? anticoagulant rodenticides threaten wildlife from both direct and secondary exposures. There is strong and mounting evidence that these materials can bio-magnify up the food chain in ways not dissimilar to DDT and its notorious derivatives which inspired Rachel Carson to sound the alarm with Silent Spring.
At a recent meeting the volunteer organization, R.A.T.S. (Raptors Are The Solution) presented helpful information for understanding the changing regulations and how to better protect against the poisoning of non target animals. Alternatives, such as the contraceptive approaches now being tested in Seattle show great promise, but we must always be wary of the industry’s tendency to simply substitute equally toxic substances instead of finding true alternatives.
Rather than rush for poisons, residents and the service professionals they employ are encouraged to learn about enhancing habitat for pest rodents’ natural predators. You can receive nest box placement and management support by calling Sequoia Adubon Society’s Cavity Nesters Recovery Program.
It is known that P-22 survived at least one collision with a motor vehicle. He suffered illnesses related to constant proximity to humans and their chemical counterparts. Rodenticides played a role in his illnesses. The first- and second-generation types of anti-coagulant poisons commonly used today sicken and kill many non-target predators and carrion eaters, including raptors and pets.
Audubon Society and the Bio Integral Resource Center‘s Guide: Protecting Raptors from Rodenticides (Common Sense Pest Control Quarterly Special Issue 2011, Published January 2013) offers important insights on how we can take measures and enlist nature’s help to safely reduce rodent populations. It is important to establish an integrated approach, utilizing all available least toxic methods. Innovations such as birth control are being developed to control rats. An example of Biological Control is when we encourage our friends of the forest to feast on rodents by providing improved habitat such as perches and nest boxes. Combining and coordinating multiple approaches is the key to effective Integrated Pest Management.
While a lot is mentioned of secondary poisonings such as occurred with P-22 who suffered years of sub-lethal effects from eating poisoned prey, primary poisonings also exact a cost to non-target species. Primary poisonings occur when an animal directly ingests poison baits. They are designed for palatability, so pets and many other non-target animals can easily be poisoned if allowed access. Non-target species may include woodmice, field voles, bank voles and even insectivorous birds!
Much of this information comes from the BIRC publication: Protecting Raptors from Rodenticides which can be purchased from BIRC at this link: The Integrated Pest Management Specialists. Please support this important non-profit that promotes ecologically sound approaches for reducing pesticide use and protecting our environment.
Best Practices for dealing with a Rat Infestation
Address any sanitation gaps and secure all trash and food sources, indoors and outside.
Regularly check for gaps where rats can gain entry -and seal them.
Remove dense landscape plantings such as Ivy (Hedera ssp) that provide harborage and pathways and facilitate entry into dwellings and structures. Prune tree branches away from buildings to prevent wall and roof access.
Use trapping methods to reduce populations (An entire course could be taught on this.)
Least Toxic Method: RatX uses a bait approach, but the lethal mode of action is dehydration from corn gluten, not chemical poisoning; thus eliminating the possibility of secondary poisonings.
If using professional abatement services, ask about least toxic options such as RatX and birth control baits such as Contrapest (currently only available through licensing agreement)
Use conventional rat baits only as a last resort if trapping and other methods fail. (First generation rat baits such as warfarin are less toxic to non target species than second generation rat baits such as bromethalin and Vitamin D-3)
Always use exclusion measures to avoid accidental poisonings, and check bait stations often.
Regularly monitor for rats and check for re-colonization. Keep awake to new methods.
Establish perches and nest boxes to encourage raptors appropriate to your area.