From the June 2009 Conservationist
Make Way for Osprey
Co-existing with this bird of prey
By Blanche Town
The office phone rings. A voice at the other end of the line enthusiastically reports that a pair of osprey is building a nest. The caller continues, "They are just down the road from our house. We love watching them. They're bringing in sticks this morning." Next comes the bad news: "The nest is on a power pole. You aren't going to let them tear it down, are you?"
Osprey usually nest in large dead trees
(Photo: Rocco Saccone, Jr.)
Calls like this are becoming more common in DEC's Region 6 office in the St. Lawrence Valley. Historically, ospreys nested at natural sites, such as in white pine trees "topped" by the elements, in large dead trees near lakes and rivers, or in standing, dead timber in flooded wetlands. More and more, ospreys are finding manmade structures to their liking. Since 2001, 60% of the osprey nests identified in northwestern New York (primarily St. Lawrence and Jefferson counties) are found on power poles, navigation cells, cellular phone towers, chimneys, and "goose tubs" (artificial nesting structures intended for use by geese).
National Grid and DEC are working
together to keep osprey safe.
Nesting on power poles can be bad news for both ospreys and electric customers. If sticks or other nesting material touching the lines cause a short circuit, the result can be a fire or an explosion, loss of power and electrocuted or injured birds. In this part of New York, National Grid is working closely with DEC to prevent these problems, by erecting nesting platforms adjacent to the poles, or by modifying the power poles themselves. This allows nesting to take place safely without loss of power or injury to the birds.
(Photo: Blanche Town)
Power poles aren't the only structures that bring ospreys into conflict with people. These large birds of prey sometimes build their nests on navigation cells in the St. Lawrence River. They frequently choose a nesting location that hinders maintenance and sometimes operation of the light. It is important that the lights are not compromised, as they serve a critical safety and commercial function-guiding ships and other boat traffic away from shoals and allowing them to safely navigate the St. Lawrence Seaway. The St. Lawrence Seaway Development Corporation has been very cooperative in modifying navigation cells by adding nesting platforms mounted atop a structure. This allows birds to nest safely away from the electrical equipment.
Ospreys feed primarily on fish, which they catch by plunging into the water feet first. With needle-sharp hooked talons, and zygodactyl feet (two toes face forward and two toes face backward), they extract their prey from the water. Like other fish-eating species, osprey populations declined drastically between 1940 and 1970 as a result of DDT-induced eggshell thinning. When the pesticide DDT was banned in 1972, osprey populations rebounded. Once listed as "endangered" in New York and some other states, the osprey is now more favorably listed as a species of "special concern."
Ospreys are typically found in our area from April to September. Satellite telemetry conducted with adult ospreys nesting on the St. Lawrence River and the Perch River Wildlife Management Area (Jefferson County) revealed that our summer residents migrate to South America for the winter months, returning as spring comes to the north country.
So, the next time you see a large bird of prey near a major watercourse, look closely. If it has a dark eye stripe, and holds its wings in an arched fashion, you may be looking at an osprey-a fine example of a bird that has figured out how to thrive in close proximity to human kind.
Blanche Town is a fish & wildlife technician 3 with DEC's Bureau of Wildlife. She monitors bald eagle and osprey activity in the western Adirondacks and St. Lawrence River Valley.
DEC wishes to acknowledge the proactive and necessary cooperation and efforts of National Grid and the St. Lawrence Seaway Development Corporation as we work together to find ways to ensure a viable osprey population, without compromising public safety.
Photo: Jeff Nadler