Are they shorebirds, sandpipers or waders, those small birds we see at the beach, on the sand and mud flats, or in plowed fields? They can be called all of the above. Why don’t they argue over the food that is available in the areas where they feed side by side? The answer is that each and every bird has a different sized and shaped bill and feeds in slightly different areas for somewhat dissimilar foods.
The shorebird’s menu consists of seed mollusks, small fish and amphibians, worms, small crustaceans and adult and larval insects. The length of their bills and legs determines what they choose from this menu. A long, curved-billed shorebird, such as the marbled godwit that is now visiting the Vineyard, can reach seed clams that have buried themselves deeper than the short-billed dowitcher’s bill can reach. So these two species can feed side by side, one at a shallow depth, the other deeper.
How about those sandpipers which seem to have exactly the same length bills? The smallest of our local peeps (small sandpipers) is the least sandpiper. It feeds in areas along with semipalmated sandpipers and plovers. The plovers have short, heavy bills and pick up insects and spiders on the sand or mud surface. The two sandpipers are tricky. The semipalmated sandpipers tend to stay close to the water’s edge and probe shallowly and quickly. The least sandpipers tend to be slightly inshore from their cousins, feeding on the drier flats. They also probe shallowly or peck at the surface. They feed slowly and move less than the semipalmated sandpipers.
Greater and lesser yellowlegs have slightly different length legs and bills. What is the greater yellowlegs’ “restaurant” of choice? Knee-deep saltwater is where this larger yellowlegs is found. It stabs into the water when it sees its prey, which is usually small fish. It is a more frantic feeder than lesser yellowlegs. The lesser yellowlegs prefers shallower water, although unlike its bigger cousin at times it will swim to catch its dinner. Both yellowlegs eat about the same diet, one in shallower water than the other.
So food fights are rarely an issue with shorebirds. They have adapted in such a fashion that they can feed close to one another without much conflict. The problems come when their habitats are destroyed and excessive numbers of shorebirds are forced to feed in a small area that does not produce enough food to go around.
Bird Sightings
Marbled godwits seem to enjoy the tidal flats at Katama as well as Tisbury Great Pond. Susana Caron watched a marbled godwit march by her beach towel as she lay on the beach at Quansoo on August 5. Page Rogers took her kayak out to Norton Point on August 7 and spotted the marbled godwit feeding with short-billed dowitchers and greater yellowlegs. Pete Gilmore and Lanny McDowell also spotted the marbled godwit at Norton Point earlier in the day. Both parties also spotted black terns and Lanny and Pete saw the two black skimmers.
Allan Keith, Lanny McDowell, Bob Shriber, Mark Foster and I were at Quansoo on August 8 between 7:30 to 9:30 a.m. and spotted a black tern, 16 piping plovers and a marbled godwit on the flats by the opening. Is there more than one marbled godwit on the Island?
Roy Hope reported that the black skimmers were still in the tern colony at Norton Point on August 8. The same day Page Rogers photographed a whimbrel on the Chilmark Pond flats. Winnie and Fred Spar were at Norton Point on August 9 and spotted the marbled godwit, both Sandwich and black terns and the two black skimmers between 7 and 9 a.m. Eleanor Waldron and I joined Lanny McDowell and Porter Turnbull at Norton Point on August 10 and found no godwit, neither black nor Sandwich terns, but did spot the two black skimmers and an ailing Cory’s Shearwater.
Gus Ben David was the recipient of a northern waterthrush that hit Nancy Rogers’ window on Oak Lane in West Tisbury on August 4. That is a bit early for this warbler to be migrating although we have had records as early as July.
I received a message from Richard Toole that he had seen a snow goose in with a flock of Canada geese at Farm Pond on August 11. I checked with Gus Ben David and found that the male of his pair of snow geese is full winged and occasionally goes “walkabout” for a few days and then returns to the World of Reptiles and Birds to be with his mate. Undoubtedly the bird Richard saw was Gus’s male.
August 9, Dick Jennings sent me a great photo of a male kestrel perched on a post. He mentioned that the bird had been hanging around Wasque putting on quite a show chasing bugs. This is probably the bird the Chilmark Community Center group spotted on August 4.
Joan Jenkinson, Bob Fogelson, and Tom and Barbara Rivers have all commented on the enjoyment they are having from watching their ruby-throated hummingbird adult and young sharing their feeders. Tom mentioned that the young hummingbirds have shorter bills. Dale Carter called from Chappaquiddick and mentioned she had a plain green and white hummingbird dancing in front of her window; no doubt either a female or young ruby-throated hummingbird.
Peter Kramer reported a sizeable flock of tree swallows roosting near the edge of Tisbury Great Pond on August 10.
Bob Shriber birded Great Rock Bight on August 10 and spotted yellow warblers, American redstarts and eastern wood pewees. At the Gay Head Cliffs he spotted two northern orioles. The following day he was joined by Mark Foster and they found a pine warbler on the Quansoo Road and at Katama a saltmarsh sharp-tailed sparrow and at the Farm Institute a bobolink.
The Chilmark Community Center group went to Great Rock Bight and we also spotted American redstarts, yellow warblers, a zillion gray catbirds and an eastern phoebe.
Tim and Sheila baird have a rowdy family of Carolina wrens in their Edgartown yard. They also have a pair of northern orioles and young visiting their trumpet vine. The oriole poke a hole in the base of the flowers and suck out the nectar!
Please report your bird sightings to the Martha’s Vineyard Bird Hotline at 508-627-4922 or e-mail to birds@mvgazette.com
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