Cat Toxoplasmosis and Wildlife Welfare

Toxoplasma gondii shed by cats causes significant wildlife mortality in prey species, with management practices that reduce environmental contamination benefiting both wildlife and human health.

Key Facts

Cats are the definitive host for Toxoplasma gondii — other animals are intermediate hosts
Sea otters in California show toxoplasmosis-related mortality from land runoff containing oocysts
Hawaiian monk seals and spinner dolphins have also died from toxoplasmosis from cat feces
Cats that hunt wild prey or that are fed raw meat have higher infection rates
Toxoplasma oocysts survive in soil and water for months and are resistant to most disinfectants

Welfare Considerations

Cat toxoplasmosis wildlife welfare impact is diffuse but significant: marine mammals that encounter terrestrial runoff containing Toxoplasma oocysts have no evolved immunity to severe infection. Land cats near coastal waterways represent a real pathway for toxoplasmosis affecting marine mammals. The welfare prevention measures — keeping cats indoors or reducing hunting, preventing litter box runoff, not flushing cat feces — reduce environmental contamination and protect wildlife welfare. The same measures reduce human health risk from the parasite.

What You Can Do

Keep cats indoors to reduce hunting and toxoplasmosis transmission
Never flush cat feces — dispose in sealed bags in general waste
Prevent cat litter runoff from reaching garden drainage and waterways
Worm cats regularly to reduce overall parasite burden
Support coastal wildlife monitoring programmes that track toxoplasmosis as a marine mammal welfare concern