It’s the season for the ospreys to return, which, along with the arrival of red-winged blackbirds and other migrant icterids and an uptick in birdsong volume and variety, signals a kickstart in bird awareness right about this time each year.
Soo Whiting mentioned last week in this column the Dropicks’ report of an osprey pair at My Toi on Chappaquiddick. These birds were seen on March 3, a very early date. In the original Vineyard Birds, published in 1983, the earliest record for a spring osprey was March 23, 1979. Then, in Vineyard Birds II, published in 2007, the earliest sighting was on March 14 in 2002. So the trend over the last decades seems to be toward earlier sightings overall. Where these early arrivals spent the winter is another question which, the way osprey research is progressing, will probably be revealed before too long.
Here is a collection of bits of information about ospreys, the Vineyard’s and otherwise, gleaned from a perusal of publications and online resources.
In the 1950s there were thought to be somewhere between five and ten pairs nesting on the Vineyard. During the 1960s the number of breeding pairs got down to two or three, and nine breeding pairs were reported in 1979. These days we can expect 60 to 70 pairs that are actually considered breeders by the census-takers.
The overall length of an adult osprey averages about two feet with a wingspread of 63 inches and weight of 3.5 pounds. As is the case with many raptors, an osprey female is somewhat larger than her mate. Also, whereas males are usually an unmarked white on the breast, females often have a necklace of small dark streaks across the upper chest.
There are a couple of ways that you can tell young ospreys from the adults. While the backs and wings of adults are all dark, there are pale buff fringes on those feathers in juvenile plumage. This gives the youngsters a scaly look to the upperparts. Immatures show a narrow white border on the tip of their tails and the trailing edge of their wings. Also, the eyes of a young osprey start out as red and then fade to orange, becoming a bright yellow in adults.
From Hawks of North America we learn that ospreys are thought to be most closely related to another raptor family, the kites. Their outer toes are reversible, so that, as owls do, their feet form a “four-cornered net of talons” as they dive feet and head first, frequently disappearing entirely below the water to seize their fish prey. Holding on to a slippery fish is aided by a specialized feature of their feet called spicules. And you will notice that an osprey always carries its fish prey with the head aimed forward. Their capture rate for a dive is about fifty per cent. Not nearly so high a ratio for the learning young, I would imagine.
A couple of items from Hawks in Flight caught my attention. “The bird adjusts the angle of the dive to compensate for the refraction in the image of the fish swimming below the surface.” And, “A migrating osprey may be seen carrying fish past hawk-watch sites – ‘packing a lunch,’ as it is called in the hawk-watch vernacular. These watch sites are often miles from the nearest fishable body of water.”
While we are used to seeing osprey nests built in tall trees or constructed on man-made nesting platforms — well over one hundred platforms have been erected on this Island alone under the supervision of Gus Ben David, formerly the director of Felix Neck Wildlife Sanctuary, and his volunteer crews — fish hawks have nested on the open ground, on a duck blind, on chimneys, on outhouses and on a lobster pot.
One final anecdote on ospreys. My friend David Stanwood, years ago on an April day, was walking between his house and his workshop, which is adjacent to the big field at The Nature Conservancy property near Duarte’s Pond off Lambert’s Cove Road. It was the day of the spring fishing tournament at the pond, when youngsters and not-so youngsters gather to get their lines wet and to have a go. The pond had been well stocked with trout the day before. The tradition of the stockers was to include in the release one large golden trout which would make some lucky angler a prize-winner. David’s peripheral vision picked up an osprey nearly overhead motoring toward the east. From way above the osprey, another raptor dropped at a great speed, directly toward the osprey. Just before apparent impact the red-tailed hawk swerved to the side, but the assault was enough of a shock to make the osprey turn upside-down to defend itself with its talons aloft, and at the same time releasing the prey it clutched. David looked on as a sizeable object cartwheeled down out of the sky, strobing bright as it dropped, and thudding on impact only feet away. It was a large and beautiful golden trout.
Bird Sightings
Of the bird sightings reported to various forums this week a few notables follow, most of them from the Oak Bluffs area.
Guess what the cat brought home? For Richard Greene in West Tisbury it was a male bobwhite right on his doorstep on Tuesday, March 12. Hate to lose even one.
Alice Goyert emailed a photo she took of at least 18 cedar waxwings. People with feeders continue to report healthy numbers of dark-eyed juncos and red-breasted nuthatches.
The pair of ospreys observed by Dorothy and John Dropick at the nesting platform near My Toi on Chappaquiddick was not observed on subsequent visits after the initial sighting on March 3.
John Nelson and Michael Tinus went out on Sunday, March 10, and had, at the head of the Lagoon, one pied-billed grebe, 13 greater scaup, five American coots, 18 common grackles, a tight flock of 20 blue jays and one very small Canada goose in the freshwater pond, which they surmised might be a lesser Canada goose. At Ocean Park in Oak Bluffs the brant horde numbered over 100. They picked up an immature black-crowned night heron at Farm Pond, 14 common goldeneyes at Sengekontacket and their first American oystercatcher of the season on State Beach. Another American oystercatcher was seen on Sunday, this one by Scott Stephens, at the Lagoon, fairly close-in to Vineyard Haven proper.
One week earlier, also at the head of the Lagoon, Patsy Donovan spotted the five coots, a horned grebe, a group of greater scaup and later, near the south end of the Oak Bluffs sea wall, she counted eight purple sandpipers on the jetties across the road from Farm Pond.
On March 10, Rob Culbert took birders out on a tour and picked up one snow goose in with the Canada geese at the Farm Institute, which also hosted a flock of about 100 horned larks that have been lingering in the fields near the Mattakessett end of the property. Close by they found a killdeer near the horse barn at Herring Creek Farm.
Terry Appenzellar wrote, “Tuesday March 12: As I sit at my desk upstairs, looking out at Crystal Lake, a northern flicker is drumming his heart out on our second story gutter!”
And finally, Suzan Bellincampi at Felix Neck has just announced the arrival of the first egg of a new batch from the sanctuary’s resident mother barn owl. Rejoice!
Lanny McDowell is a fine arts painter and bird photographer living near Tashmoo in Vineyard Haven.
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