Thursday, April 11, 2013

New Jersey Osprey Project

days old osprey at Great Bay

The osprey was listed as an endangered species in 1973 and quickly after that the New Jersey Osprey Project began.

Starting with a spring 1974 aerial survey to determine the number of active osprey nests from Toms River to Atlantic City, the results were not good.

With a baseline historic count of 500 osprey nests, it was expected that the numbers would be down due to the effects of DDT and habitat loss and in the 1974 count only 50 nests remained.

New Jersey habitat was also lost because of a growing shore population. New construction eliminated trees needed for nesting and it increased the ground predator populations.

The project began to supply man-made nest platforms for the birds to replace snags and trees that lost to development on the barrier islands.

DDT in the food chain caused reproduction to fail. DDT was banned in 1968, but the negative effects and residual DDT continued for a number of years. Used in and near marine environments, it was absorbed by both organisms and soils and accumulated in the food chain. Because DDT is fat soluble it bioacummulated in predators, especially birds of prey.

It did not kill the birds, but rather caused the thinning of eggshells which often broke under the weight of the incubating female.

3 young
By 1986, the osprey population had surpassed 100 pairs. This allowed their status to be changed to "threatened"in NJ.

During that time, some of my volunteer work for the Endangered and Nongame Species Program involved monitoring and tracking nest success.

2006 found the NJ osprey population at a new post-DDT high of just over 400 active nests, and that was surpassed in 2009 with 486 nesting pairs.

The next aerial survey was scheduled for this year.

MORE
The Osprey Project at conservewildlifenj.org/protecting/projects/osprey/ and follow them on Facebook.
Endangered NJ posts on osprey


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