Thursday, June 24, 2010

Osprey Surveys Begin!

On June 21st the first of many osprey surveys began. The surveys are performed every year to help determine the overall health of the population. Most surveyors are volunteers who commit many hours of their personal time to helping us monitor the population. USGS leg bands are placed on the young that are produced. The bands gather valuable data. They help us understand where ospreys migrate and winter, their survival rates, and how behave.

An adult leaves a nest as I approach by boat in Absecon.

By this time, many osprey young are 3-4 weeks old. This is when they can be banded. Not all ospreys begin nesting at the same time, so some adults are still incubating or have young that are only hatchings to two week old young. Generally, the more experienced adults start earlier and are more successful at raising those young. Younger adults start later and have a far less chance of successfully raising young. 

Volunteer surveyors cover all major nesting colonies, from Sandy Hook south to Alloway's Creek along the Delaware Bay. The major nesting colonies are Sandy Hook, Barnegat Bay, Sedge Island, Great Bay, Margate/Ventnor/OC, Great Egg Harbor River, Stone Harbor, Avalon, Wildwood, and the Maurice River. They collect data (whether or not a nest is active & # young produced) which we use to calculate the productivity rate. Ospreys need a productivity rate of at least .8 young/nest to sustain the population. In the past 5+ years they have had more than double this rate. The population has grown by 21% in the past 3 years. Last year there were 485 nesting pairs in New Jersey. This year we expect there to be even more.

 An osprey nestlings lies low in the nest. Young ospreys rely on their plumage for protection from avian predators like great horned owls.

I hope to post more photos as I survey more areas throughout New Jersey to share my experiences while working to monitor and protect ospreys. Stay tuned for more photos and posts!


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