Last month, radio-collared mountain lion P-47 was discovered dead in the Santa Monica Mountains National Recreation Area with his likely cause of death being exposure to rat poison. A necropsy revealed that the three-year-old lion had evidence of six difference anticoagulants in his system, and had internal bleeding in his head and lungs.

Though rodenticides are intended to only target rats and mice, other animals such as raccoons, squirrels, and rabbits often mistakenly consume them as well. Poisons don’t work instantly and can cause an animal to suffer and become disoriented in the days leading up to its death, making them easy targets for predators.

Carnivorous species further up on the food chain will often prey on these vulnerable and sickly animals, thus becoming secondary consumers of the toxins. Birds and reptiles may succumb to this exposure to lower doses, while other carnivores such as bobcats and coyotes may continue to ingest the anticoagulants by unknowingly consuming multiple poisoned animals.

These rodenticides are known to weaken the immune systems of animals, making them significantly more susceptible to infection and disease. Anticoagulants in the poisons – which prevent blood from properly clotting – can cause fatal internal hemorrhaging.

Further, researchers have found strong links between exposure to these poisons and the prevalence of mange in wild populations. Mange is a highly contagious mite that burrows under the skin creating extreme itchiness, which leads to hair loss, infection, hypothermia, and starvation.

When approaching pest management, these factors must all be taken into consideration. Using indiscriminate control, such as poisons and glue traps, causes undue suffering and devastation to our wild community.