Ecosystem decay is a term coined by Thomas Lovejoy to define the process of which species become extinct locally based on habitat fragmentation. This process is what led to the extinction of several species, including the Irish Elk. Ecosystem decay can be mainly attributed to population isolation, leading to inbreeding, leading to a decrease in the population of local species. Another factor is the absence of competition, preventing the mechanisms of natural selection to benefit the population. This leads to a lack of a skill set for the animal to adjust and adapt to a new environment. Habitat fragmentation and loss lead to smaller habitat sizes, and ecosystem decay predicts ecological processes are changed so heavily in smaller habitats that the loss in diversity is more extreme than expected by fragmentation alone.
Although similar to forest fragmentation and island biogeography, ecosystem decay is what results in the event of forest fragmentation.
