When research scientists tracking P-22, the late beloved lion of Griffith Park, went to change the batteries in his GPS collar in 2014, they found him suffering from mange, a parasitic disease of the skin and hair that is connected to rodenticide poisoning.
Blood tests would later show that P-22 had two rodenticides in his system, one of which was diphacinone, a first-generation anticoagulant intended to kill rats. P-22 was lucky — the scientists treated him in the field with a topical medicine. He went on to live another eight years.
But other animals are not so lucky.