We should all be jealous of ospreys. They’re way better at fishing than we are. They spend their winters on sun-drenched lagoons in Venezuela and they visit Cuba annually without violating US law.
Female ospreys can go an entire spring and summer without having to catch their own food, since the males do all of the fishing during the nesting season – we’re talking five months of breakfast in bed, ladies.
We should be jealous, but mainly we are fascinated. How is it they are doing so well now, after being nearly wiped from the map due to DDT poisoning in the 60s? What are they thinking when they build their nest in the crow’s nest of a boat, on a lifeguard chair on a public beach, or a channel marker in a busy harbor? What must it be like to see with the unimaginable visual acuity of an osprey?
The Cape Cod Osprey project, based out of Mass Audubon’s Wellfleet Bay Wildlife Sanctuary with help from Long Pasture Sanctuary in Cummaquid, seeks to map and monitor as many of the osprey nests on Cape Cod as is humanly possible. With the help of an enthusiastic network of volunteers and cooperators like Waquoit Bay National Estuarine Research Reserve, we have mapped over 300 nest sites and have received data on well over 100 active nests per year over the last 8 years.
We have learned that there are, scientifically speaking, a wicked lot of ospreys now nesting on Cape Cod compared to what we thought just 10 years ago. And the population is still growing, as evidenced by the robust number of chicks being fledged per nest (known as productivity, this is the standard measure of breeding success). Cape Ospreys are producing close to two chicks per nest on average, which is well above what is needed for population growth. We’ve gone from maybe one nesting pair in the 1970s to over 200 today. The Osprey recovery is one of the great American conservation success stories.
So why continue to monitor a species that has been saved? After all, they are no longer on the state Endangered Species list, they are nearly saturating appropriate breeding habitat, and the platforms provided by humans allow near predator-free nesting opportunities compared with the old-fashioned tree nests.
Nevertheless, they are inextricably linked with the health of our coastal environment, as their history with pesticides has proven. A 2009 article in the Journal of Toxicology and Environmental Health declared the osprey to be a “worldwide sentinel species for assessing and monitoring environmental contamination in rivers, lakes, reservoirs and estuaries.” Common species still have a lot to tell us and are worth keeping an eye on – look no further than the Little Brown Bat, which thanks to an introduced fungus has gone from common as chickadees to the verge of extinction in less than ten years.
So help us keep an eye on this iconic and charismatic coastal predator. You can monitor as many or as few nests as you want. While nest observations start in March and April, the most important data is how many chicks fledge from the nest during the summer. To get involved, contact Wellfleet Bay Wildlife Sanctuary and we will add you to our growing list of Osprey nest voyeurs – I mean, citizen scientists…
This episode of the Bird Report originally aired in March, 2016.