Is the Osprey population in New Jersey OK?

Osprey (Pandion haliaetus) were on the brink of extinction in the 1970′s due to overuse of pesticides such as DDT in the 1950′s and 1960′s but they have made a major comeback.  Their conservation status in NJ is as a Threatened Species and Osprey have similar status in other states.  These raptors are not listed under the Federal Endangered Species Act.

How many Osprey live at Island Beach State Park?

There are approximately 30 nesting pairs of Osprey in the park.  They are one of the most widespread species of birds found throughout the world, on all continents except Antarctica.

What do Osprey eat?  How do they catch those fish?

Osprey primarily eat fish, accounting for 99% of their diet.  They are remarkably well adapted for catching fish:

• Osprey have excellent eye site and can see swimming fish from up to 100 feet above the water.
• They dive to water surface and swing their legs forward and grasp the fish.
• Their feet have barbed pads on the soles to help grip slippery fish.
• They rotate their outer toes around to the back so they hold the fish between two toes facing forward and two from behind.
• The Osprey’s rounded talons with backward facing scales help them grasp and carry the fish.
• They orient the fish headfirst to make it as aerodynamic as possible
• When they return to the nest or perch nearby, the male eats first then the rest in the nest–he has to have strength for the next fishing trip.  Usually they eat the fish from head to tail.  The male may catch up to 10 fish per day to feed his hungry mate and chicks.

When are the Osprey at Island Beach State Park?

Osprey return to Island Beach mid to late March and migrate south in late August or early September.

Where do the Osprey spend the winter?

Osprey from the mid-Atlantic states end up in South America.  They migrate predominantly in the day time covering an average of 160 to 175 miles per day.  Males and females migrate separately and to different destinations.

Do the same birds occupy the same nests year after year?

Generally, Osprey mate for life and often return to the same nest sites and spend about five months together to raise their young.  Last summer one of the birds occupying the nest we are watching had a leg band.  Neither bird on the nest this year has a leg band.  We must have a different pair this season.

Why do osprey live on platforms?  Where would they live if there were no platforms?

Osprey prefer to nest on high ground or over water.  These locations protect the nest from predators.  Without platforms Osprey would seek out the tallest trees.  Scientists have found that Osprey nests built on manmade structures fledge more chick than natural structures.

How many chicks usually hatch?

With good conditions (clear water and lots of fish) a pair of Osprey may have up to three or four eggs in a season.  Osprey eggs don’t hatch all at once, but are staggered in time so that some siblings are older and more dominant.  When food is scarce or weather is bad making water cloudy and fishing less successful, the older stronger chicks may take all the food leaving their siblings to starve.

When do the chicks learn to fly?

Osprey chicks usually hatch in mid to late May after about 5 weeks of incubation.  In June and July their feathers will come in.  They’ll be flapping their wings in July and leave the nest for the first time 8-10 weeks after hatching.  Then in late August or early September make their first migration south.  The typical lifespan is 7-10 years.

Do Osprey have any predators?

Adult Osprey are apex predators meaning that they have no predators of their own as they reside at the top of their food chain.  Osprey chicks are vulnerable to attacks from other large birds including crows, hawks, and owls.  Adults protect the chicks from attack and also from inclement weather.  The female will cover the chicks in cold and rain and she will spread her wings to shade the chicks in extreme heat.