Why are fewer birds migrating?
Migrating birds face a tough journey between their winter and summer homes. Unfortunately, studies have shown that fewer birds are surviving to make this extraordinary trip each year. Not only do they face natural perils such as storms, predation, and drought, they now contend with ever increasing human caused threats. These threats include contamination from pesticides, herbicides, and industrial pollution. Birds are also losing their homes and migration stop-overs through timber harvesting, urbanization, grazing, and farming. Land management practices that “fragment” habitat into smaller, more isolated patches, make it easier for predators and cowbirds to find nests of other species. Cowbirds parasitize these nests by laying their eggs in them. This leaves the “foster parents” to raise cowbird young at the expense of their own.
