The main issue with feral cat populations is the ecological harm they can cause, feral cats are uniquely capable of harming local species due to their general adaptability and their status as an apex predator. Feral cat populations have been linked to the endangerment of many bird species and they unbalance the ecology of any area in which they inhabit, especially if they go unchecked by human measure as cats reproduce extremely quickly. Feral cats can also carry significant diseases, which may contribute to the fact that feral and outside cats have an overall lower lifespan and generally worse welfare.
