Cause: Sport hunting, predator control, retaliation.

Effect: Some species are locally extirpated. Unregulated or illegal killing disrupts ecosystems.

Cause: Rodenticides, herbicides, insecticides.

Effect: Non-target animals suffer secondary poisoning, like hawks, owls, foxes, and bobcats eating poisoned prey. Insects that birds and amphibians rely on are also harmed.

Cause: Urban development, agriculture, deforestation, road building.

Effect: Animals lose access to food, shelter, and breeding grounds. Populations become isolated, which reduces genetic diversity and resilience.

Cause: Roads cutting through wildlife habitats.

Effect: Millions of animals are killed annually by vehicles. Some species suffer major population declines in road-dense areas.

Cause: Free-roaming domestic cats and dogs.

Effect: Cats alone kill an estimated 2–4 billion birds and 12+ billion small mammals annually in the U.S. They also spread disease to wildlife.

Cause: Greenhouse gas emissions from human activity.

Effect: Alters habitats and food availability, disrupts migration and breeding cycles, increases disease and extreme weather events.

Cause: Unsecured garbage, intentional feeding, compost, pet food.

Effect: Wildlife become dependent, lose fear of people, and are more likely to be hit by cars, harmed, or euthanized as “nuisance” animals.

Cause: Cultural myths, exaggerated media, lack of education.

Effect: Snakes, bats, coyotes, and others are killed out of fear or misunderstanding, even when they pose no threat and serve important ecological roles.