Oh, not intentionally. Of course not. But maybe indirectly?
According to AudubonMagazine.org, if you’ve used so-called second-generation anticoagulant rodenticides, rat poisons sold under brand names like d-Con, Hot Shot, Generation, Talon, and Havoc, you’ve likely killed owls—as well as hawks, eagles, vultures, and mammals like cats, foxes, and other rodent eaters.
Rodenticides kill by thinning an animal’s blood. Death results from internal bleeding. But owls come into the picture indirectly.
From the time a mouse or rat first eats poison, several days pass before it dies. Meanwhile, it returns to the bait repeatedly, ultimately ingesting many times the lethal dose. The rodent grows lethargic, unable to dart to cover, and becomes an easy target for its natural predators, including owls. When an owl enjoys the easy catch, it ingests a massive doze of rodenticide.
In turn, then, the owl suffers from secondary poisoning. It dies from stomach hemorrhaging. Or, worse yet, the adult owl feeds the mouse to its babies. Owlets die.
Here’s the rest of this horrible scenario:
When we kill owls and other mouse and rat predators, we’re killing the very animals that nature provides to control rodents. If we eliminate natural rodent control, the rodent population will grow exponentially. You see where this is going, right?
According to a ScientificAmerican.org report, two states for which statistics are available—California and New York—reveal staggering numbers. A 2002 study verified that New Yorkers in eight zip codes applied 20 tons of rodenticides annually. A 2004 study revealed that Californians purchased 10 million pounds annually. The Tri-State surely isn’t exempt from proportionately similar use. You can do the math.
In 2011, new EPA rules went into effect but with little impact. Three major manufacturers were exempt, and professional exterminators, farm workers, warehouses, and other commercial installations were excluded. Rodenticides remain readily available.
According to Audubon author Ted Williams, “There's no safe place or safe delivery system for second-generation rodenticides.”
Okay, let’s be honest. Mice or rats invading one’s premises repulse most folks. We know the negatives; rodents carry disease. So what’s a responsible person to do?
Audubon posts this message:
“Safe alternatives include single- and multiple-entrance snap traps, electrocuting traps, glue traps (provided you use them only indoors and frequently dispatch stuck rodents), and even first-generation baits (as opposed to the second generation baits referenced above) with these active ingredients: chlorophacinone, diphacinone, diphacinone sodium salt, warfarin, and warfarin sodium salt.”
Audubon also recommends a “better mouse trap”:
Run a metal rod through holes drilled in the center of both lids of an emptied tin soup can so the can becomes a spinning drum. Fasten both ends of the rod to the top of a plastic bucket via drilled holes. Coat the can with peanut butter. Fill the bucket with water and a shot of liquid soap (to break the surface tension and thus facilitate quicker, more humane drowning). Rodents jump onto the can; it spins them into the water.
Using the trap at his fishing camp, Williams killed 37 mice over three months. No owls died.