DDT was widely applied to control mosquitoes and other insects. It is a long-lived poison which bioaccumulates in the food web, and becomes concentrated enough in top predators to cause eggshell thinning and death. When DDT was banned, peregrines, osprey, bald eagles and other carnivores at the top of the food chain rebounded with a little help from wildlife management activities. We now have 15 to 17 pairs in New Jersey. Nesting birds continue to receive monitoring, and young are banded annually by biologists.
Volunteers check the progress of young in the nests from a distance.
All nesting peregrines in New Jersey use man-made sites, like tall buildings and bridge spans. The peregrines in Jersey City's 101 Hudson building were first spotted by L-Cor employee Bob Barth. Last year, a three-sided nest box was located on the roof of the building which the birds took to right away. Building employees were alerted to the birds' presence, and were very protective of their resident endangered species. Last year the pair produced 2 young.