Limited study done in Maine shows rodenticide exposure in black bears

Of four bears sampled, all four tested positive for rodenticide exposure. View the report

As black bears are opportunistic omnivores, sublethal poisoning could be due to secondary exposure to anticoagulant rodenticides from preying on and scavenging other animals that have consumed poison, from ingesting the bait directly, or a combination.

Rodenticides can persist in animal tissues for up to a year. Over time, chronic sublethal poisoning results in weakened immune systems and sarcoptic mange, as well as other disease.

Mange was virtually unheard of in black bears before the widespread use of SGARs. Researchers have noticed an increase over the last couple of decades and began asking why.