There are three people that I consider osprey men: Rob Bierregaard, Gus Ben David and Tim Baird. On Tuesday night, Rob gave a talk about ospreys. For those of you that were unable to attend, you missed a good one. For those of you that did attend, bear with me as I review some of the new facts I learned and some old ones that were dredged up from my memory by Rob’s marvelous talk.
The greatest news is that there are now 69 active osprey nests on the Vineyard. This is an amazing number especially because in 1969 there were only two pairs. The ospreys in these 69 nests have fledged 121 young this year. Wow, that is twice as many as last year. Another amazing piece of information — two of the nests reared four young. Osprey generally lay three eggs and usually only fledge two young. One can only surmise that the food supply has increased to such a degree that the osprey pairs were able to lay more eggs and successfully rear more young. Gus Ben David added that our ospreys have gone oceanic — they are feeding on offshore fish bringing in small bass, bluefish and other offshore species. One only has to walk South Beach or cruise between Gay Head and Noman’s Land to see the Island osprey fishing in the ocean. Our ponds do not have enough food to satiate the osprey population.
Over the years, Gus Ben David along with Tim Baird and crew have erected the 122 osprey poles on the Vineyard. This is the main reason we have so many osprey pairs. The real question is if the Island has produced between 50 and 121 young each year, why aren’t all the osprey poles being occupied? Rob and crew are still trying to figure that one out.
A few facts that we all should remember about our fish hawks: they are indeed fish eaters and the only records of osprey eating other items usually end up being creatures that are floating on the water, and this is very rare. Also, there is a way to tell the female from the male. The female is larger and also has a dark band across her chest. The male can have a band also, but it is duller. This band isn’t always the best indicator, but size is.
Ospreys mate for life and return to the same nest year after year. The couples take separate vacations, however. The female sits on the nest for about 37 days and then tends the young for about another four. So it is not surprising that after the breeding season, the females migrate first and leave in August. The males leave about a month later in mid-September. The adult ospreys return to the same winter “vacation” spots each year. The young adults walk about for a while and then find a spot to their liking and spend a year there before returning north for their first breeding season.
How do we know all this? Thanks to Rob Bierregaard and his new crew including Dick Jennings and David Nash, they have been able to put transmitters on both adult and young ospreys and follow their movements. That is another story and if you want more on that you should go online and see the past migrations and movements of the ospreys that have been fitted with transmitters. The Web site is bioweb.uncc.edu/bierregaard. You will want to watch this Web site this fall to see where the two ospreys that Rob is fitting with transmitters this weekend will go. Enjoy!
Bird Sightings
Rich Stanton spotted six Caspian terns at Quansoo on July 7, probably the same group we saw earlier. At Little Beach on July 9, Rich saw two Arctic terns and a possible Foster’s tern. On July 17, two fledgling northern harriers were working the marshes along Chilmark Pond. Rich also saw a Hudsonian godwit on Sarson’s Island on July 16. On July 28, Rich Stanton spotted a pectoral sandpiper on Chilmark Pond. One wonders if that is the same one we saw on Noman’s Land earlier this month. Finally Rich saw a spotted sandpiper on Chappaquiddick on July 25.
Emily Reddington saw a whimbrel at Harthaven on July 15.
Dick Jennings reports that the yellow-crowned night heron is still around Tom’s Neck on Chappaquiddick. He also checked on the merlins and found that both the male and female were still around, the male in one area and the female in another but close by and still agitated when humans are around.
Felix Neck birders have been busy. Birders reported great egret, great blue heron and willet on July 23. The next day a male harrier was seen hunting the fields. On July 27, Steve Allen and Don Gardner saw spotted sandpipers, black-crowned night-heron, and semipalmated plover on the shores of Sengekontacket. The following day Al Sgroi had two white-rumped sandpipers, four piping plovers, greater yellowlegs, sanderlings and least sandpipers at Sengekontacket. At Eel Pond, Al spotted three species of terns, common, roseate and least American oystercatchers, willet, ruddy turnstones, black-bellied plovers and piping plovers. Finally Al went to the state forest and heard wood thrush and ovenbird and watched a house wren tending the nest.
The Chilmark Community Center walk joined me at Quansoo. We had a nice selection of shorebirds including American oystercatchers, sanderlings, piping plovers, greater yellowlegs, least and semipalmated sandpipers and semipalmated plover. We learned the difference between immature and adult common terns and watched as the whole flock rose off the beach when an osprey flew overhead. There were very few least terns seen.
On July 25, Page Rogers and Annette Hall went kayaking on Sengekontacket and had a good birding day. They had green heron, American oystercatcher, 12 ruddy turnstones, both semipalmated and piping plovers, willet and a lesser yellowlegs. They spotted short-billed dowitcher and perhaps long-billed dowitchers. They are going to return to the same area and try to get photos of the long-billed dowitchers as they are fairly rare on the Vineyard. On July 26, Page and Annette went to Katama where they saw many of the same species as well as roseate terns and sanderlings.
Please report your bird sightings to the Vineyard bird hot line at 508-627-4922.
Susan B. Whiting leads bird walks from the Chilmark Community Center on Tuesdays at 8 a.m.
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