Ospreys are a common sight on the Westport River, a great achievement for a bird that was once so close to extinction.
On July 19th a group from the Manomet Center gathered in Westport, MA, to observe the Osprey Monitor Program in the field. Led by Cornell Ornithologist Alan Poole, Massachusetts Audubon Osprey Monitor Anna Salinas and Manomet Councilors Betty Slade and David Cole, the group toured the Westport River to observe the banding of juveniles.
In the 1940s there were around 1,000 breeding pairs of osprey from New York to Boston, until the species suffered a population crash in the 1960s and 70s as a result of the spraying of pesticides such as DDT. The population numbers plummeted by about 90 percent and by 1964 there were only 11 pairs in Massachusetts. The banning of dangerous pesticides in 1972 and the construction of the tall poles topped with platforms to serve as nests have helped the osprey to recover to almost historic numbers.
“Some of the densest populations we have seen are in West Long Island and Cape Cod,” Poole said. “On the Cape alone there are over 200 breeding pairs which is simply amazing.”
The Westport banding program was launched by Gilbert and Josephine Fernandez in 1963 as a way of identifying birds and gathering information. At least 100 platforms have been installed in the Westport River and Allen Pond area and today they support 75 to 80 breeding pairs, making it one of the most significant breeding areas in North America.
Poole explained that the breeding success depends on the weather and the available fish population, both of which had been favorable this year.
“The survival rate required to continue the species is 1.8 chicks a year, and recently we have been finding nests with two sometimes three juveniles which is extremely rare,” he said.
The Manomet group witnessed one of these chicks being banded out on the water. Anna Salinas, who banded the juvenile, explained that the 30 day old chick was still unable to fly and was one of two chicks in the nest.
Salinas said that just because the juvenile was found in the nest doesn’t mean it was born there.
“Ospreys are very adaptable in that they will raise any chick that is in their nest,” she said. “Once we found a juvenile in the marsh and we were able to place him in a nest where we knew there was only one other chick and the parents accepted him.”
Once they are capable of flying the young will winter in Venezuela before returning to Westport to nest.