Return of the Inspiring Osprey

“To be whole. To be complete.
Wildness reminds us what it means to be human,
what we are connected to rather than what we are separate from.”

Quote by Terry Tempest Williams

Story by Tyler Maikath, HCT Outreach & Stewardship Coordinator
Photos below by Diane Lomba, inset photos by Janet DiMattia

Every year, I await the sighting of my first Osprey hovering over the water, preparing to dive for a fish, marking the end of the depths of the New England winter. Seemingly in concert with the vernal equinox during the third week of March, Ospreys return from their South American wintering grounds, a migration of over 3,000 miles to the marshes and kettle ponds of Cape Cod.

I imagine what a shock it must be to leave the tropical wetlands of Brazil and Venezuela for the dreary rains and biting winds of our shores along the North Atlantic! But, the Osprey (Pandion haliaetus), or fish hawk, cares little about the trek as long as the destination provides shallow, open (fresh or salt) water habitats where they can hunt in their swift, plunging dives as their diet is 99% fish or “piscivorous.”

This raptor species lives across the globe on every continent except Antarctica with four genetically distinct subspecies. Mating for life, female Ospreys arrive shortly after their mates from their separate wintering grounds. Upon return, the male will woo his mate with a swooping, acrobatic “sky dance,” often with a glimmering fish in his talons, as if to remind her of an ability to help provide for a family together. After she eats this fish gift, a brief mating encounter often follows.

The nest is assembled with a variety of branches and the female lays a clutch of up to 4 eggs in early April, which she begins to incubate immediately. Over time, Ospreys build huge nests, weighing up to several hundred pounds, and over time the raptors can seem to be swallowed by the nest’s enormous size. Early-nesting pairs have a reproductive advantage, perhaps because their timing is in concert with the seasonal bounty of migratory adult river herring.

I’m always floored by the parental patience and perseverance of these birds, continuously incubating their eggs for about 6 weeks in all kinds of extreme weather. And then, when the eggs hatch, the young are nest-bound, relatively helpless for an additional 8 weeks before fledging, wholly dependent upon their parents for feeding. One of the purest joys of a Cape Cod summer is watching an Osprey family learn to hunt together in azure July skies.

Like many others, I am drawn to Ospreys for a variety of reasons, not least of which is because they are unusually easy to observe with their large size, loud whistling calls and conspicuous as well as charismatic behavior. Given the lack of naturally occurring tall snags (dead standing trees) for nest building, the Osprey often defaults to other structures for nest building and seems to have adapted with a fair degree of tolerance for human proximity. They nest on channel markers, jetties, greenhead fly box traps, utility poles, chimneys, and of course, artificial platforms that we build just for them. In more remote areas of the world, but rarely in southern New England, they still nest in trees.

When fish are plentiful, Ospreys also seem to be at ease with other Ospreys nesting close by. You can see Ospreys nesting in closer, greater numbers along the Westport River, in the Barnstable Great Marsh, and elsewhere. They are now among the most commonly observed raptors here, iconic during the Cape Cod summer, and numbering in the hundreds of pairs, but that was not always the case.

Though first synthesized in 1874, dichlorodiphenyltrichloroethane, or DDT, was not widely used as an insecticide until World War II. Over the following 25 years, DDT became widely used in a variety of insecticidal applications, especially to combat mosquitos. However, like other organochlorine pesticides, DDT is extremely persistent in the environment, and progressively accumulates up the food chain, a process known as biomagnification. As a fat-soluble compound, DDT accumulates in the liver and other vital organs. Over time, the toxic effects of DDT biomagnification in hawks, especially fish-eating birds, caused widespread reproductive failure and even death as organochlorine pesticides are hormonally-disrupting chemicals.

The Osprey population crashed, numbering fewer than 100 in New England by the 1960s. As bird populations plummeted, a US Fish and Wildlife Service researcher named Rachel Carson became alarmed by the harm that the widespread use of DDT and other pesticides were causing. She resigned from the service and devoted the rest of her life to writing Silent Spring, the first classic of the modern environmental movement. Her clear-eyed, eloquent, and passionate writing inspired many followers, and played a key role in educating the public about the dangers of DDT.

One such follower was Dennis Puleston, an ornithologist and the Technical Director of the Brookhaven National Laboratory. Puleston collected Osprey eggs from failed nests on Long Island and had them tested for DDT, which yielded the expected results of high levels of DDT being present. As a result of this research, he and other scientists banded together to sue Suffolk County, New York for its use of DDT, resulting in a local ban on DDT use, and a landmark victory for the environmental movement. DDT bans soon spread around the country, resulting ultimately in the formation of the federal Environmental Protection Agency. DDT was eventually banned in the United States in 1972.

Following the ban of DDT, the populations of Ospreys and other raptors rebounded relatively quickly, both locally and nationally. Today, the Osprey population now numbers around 30,000 pairs in North America. Ospreys were greatly assisted in their recovery by the building of human made nesting platforms, which are now prevalent throughout coastal New England. These platforms afford safer nesting as the adults can more easily spot potential predators like Great Horned Owls.

At Harwich Conservation Trust (HCT), we have long been involved with Osprey conservation. HCT installed its first Osprey nesting platform at the A. Janet DeFulvio Wildlife Sanctuary along the Herring River in 2006. This platform hosts a huge Osprey nest which is occupied year after year. While repairing this platform late last fall, I was shocked to hear a noise from the nest, since the Ospreys had migrated months prior. All of a sudden, a huge raccoon sprang from the nest, 20 feet up, and landed down in the surrounding marsh! Though dazed, the raccoon quickly ran away and disappeared into the marsh. Apparently, I had disturbed her or him from an afternoon nap.

Last November, AmeriCorps Cape Cod members and HCT volunteers assembled and installed a new osprey nesting platform in the salt marsh tucked behind Red River Beach. These 2.7 acres were generously donated to HCT in 2015 by Barbara and Peter Sidel. This prime location will hopefully host a new nesting pair in the coming years. HCT volunteers will be monitoring this location and other Osprey nests throughout Harwich this spring as part of an ongoing annual effort to continue to collect information on the hundreds of Ospreys that nest on Cape Cod in collaboration with Mass Audubon’s Wellfleet Bay Wildlife Sanctuary. I very much enjoy seeing the connections that HCT volunteers make with these fascinating birds.

The story of the Osprey is hopeful and proves that humans have the power to help wildlife populations recover and become more resilient to future changes. Personally, Ospreys have inspired me to become a conservationist, and have shown me how to connect deeper to the natural world. These majestic birds can have a profoundly positive meaning for many.

My colleague Michael Lach, HCT’s Executive Director, has had a similar experience of osprey inspiration. In 1983, his sixth-grade class participated in an osprey platform project organized by his father Herb Lach, Nauset teacher Dennis Pearl, and biologist Don Schall. “We installed the platform in February and Ospreys nested by March, signaling the start of their recovery in the Pleasant Bay Watershed. That first osprey nesting project had a positive impact on me as a kid, my classmates, the community, and the environment. I’m grateful to my Dad, my Mom, and teachers along the way. We hope to see more ospreys nesting in Harwich this spring thanks to HCT supporters, volunteers, and AmeriCorps,” said Mike.

The following poem beautifully captures the wonder and inspiring spirit of the Osprey. 

The Osprey by Mary Oliver

“This morning

an osprey

with its narrow

black-and-white face

and its cupidinous eyes

leaned down

from a leafy tree

to look into the lake – it looked

a long time, then its powerful

shoulders punched out a little

and it fell,

it rippled down

into the water –

then it rose, carrying,

in the clips of its feet,

a slim and limber

silver fish, a scrim

of red rubies

on its flashing sides.

All of this

was wonderful

to look at,

so I simply stood there,

in the blue morning,


Then I walked away.

Beauty is my work,

but not my only work –


when the fish was gone forever

and the bird was miles away,

I came back

and stood on the shore, thinking –

and if you think

thinking is a mild exercise,


I mean, I was swimming for my life –

and I was thundering this way and that way

in my shirt of feathers –

and I could not resolve anything long enough

to become one thing

except this: the imaginer.

It was inescapable

as over and over it flung me,

without pause or mercy it flung me

to both sides of the beautiful water –

to both sides

of the knife.”

Poem by Mary Oliver, West Wind: Poems and Prose Poems