The Osprey Connection

Despite successive early and mid-March wintrey nor’easters, and another to come this week, the first wave of ospreys is back ... and right on schedule. Some colleagues who are avid birders recorded their first ospreys of the year during the first week of March; my first sighting this year was on March 18, while I was surveying for river otters on the Peconic River.Another interesting observation made while traveling around Long Island this winter looking for otter sign is the number of new osprey nests. There seems to have been quite a boom in our East End osprey population since I last monitored them in 2001 while working at the Group for the East End. The Group is still monitoring osprey nests, so I checked with their vice-president, Aaron Virgin, about current nest numbers.

Active nests on the South Fork now number 60, up 50 percent from 2001. Most of that increase seems to have taken place in the last six years. Back around 2001, osprey productivity was lagging here, prompting The Nature Conservancy’s osprey expert, Mike Scheibel, to enlist the help of ornithologist Paul Spitzer to determine the cause. Paul’s conclusion was that there was a dearth of suitable fish prey for this piscivore, or fish-eater, and that was impacting the survival rate of the chicks.

The boom in bunker numbers here in recent years may have turned things around. Aaron reports that the number of active nests on the East End (the Group now monitors osprey nests in all five East End towns, with the exception of Gardiners Island) increased from 250 in 2013 to 370 in 2017.

There are several factors that can impact osprey productivity in a given year; weather, food and predation are the key ones. Unusually cold and wet weather during the incubation and early stages of chick development can seriously reduce hatching and chick survival rates. The ubiquitous raccoon, ignoring the cries of the adults circling around but not venturing very close, can clean out some nests in short order.

Fledged young next have to survive a long migration, winter and the return flight. The survivors will return to their natal area, perhaps make a “practice nest” their first year, and will be ready to mate and lay eggs the following nesting season.

Therefore, the dramatic increase in active nests in recent years is attributed to a number of factors, but chief among them is annual nesting success. Let’s hope this year will be another banner year for the bunker, the species that has the ability to create a ripple effect among our wide assortment of piscivores, from osprey and herons to whales and dolphins.

If you would like to help monitor or maintain osprey nesting poles in your neighborhood, contact Aaron Virgin at acvirgin@eastendenvironment.org.

Our first nesting pole repair project is next Monday, March 26, at Louse Point, Springs.