Pretend that you are a migrating robin. You have just arrived at the Gay Head cliffs after a long migration flight the previous night. You are hungry and must restore your stores of fat to power the next leg of your migration. You are looking for bushes laden with berries, and there are two choices: a bush in the middle of a large grassy patch that is laden with berries or a thick tangle of shrubs and vines.
You also realize that there are a lot of hawks — peregrine falcons, merlins, sharp-shinned and Cooper’s hawks — that may be hunting for breakfast.
Where do you go? Do you go to the berry-laden bush where you will be more vulnerable to the marauding hawks, or do you fly into the safer dense tangle of shrubs to try to find your food?
According to a recent study published in an ornithological journal, you are more likely to seek an area with a lot of fruit and dense vegetation to provide cover from predators. Why not use the best possible combination? This may explain why so many migrants can be found in woodlands in Aquinnah, especially wet woodlands like the land bank’s Gay Head moraine. But it is not one of the choices I gave you.
I left out what turns out to be an important part of the question. First, even though we have robins that spend their winter on the Vineyard, you cannot stay here because I told you that you are still migrating. You are a long-distance migrant that will spend your winter in Florida. You need to eat a lot of food to rapidly bulk up to get ready for the next leg of your journey. On the next night with favorable weather you will fly about 250 miles to southern New Jersey. So you will probably visit that berry-laden bush to eat those readily available fruits even though the predation risk is higher. You are greedy and do not leave any berries for the next robin, unless that hawk spies you and gives chase.
If you had been a short-distance migrant, maybe spending the winter in New Jersey, you are not so risky. There is no rush to bulk up for the last leg of your migration, so you head for the dense cover that provides protection from those abundant hawks. If there are not enough berries in that cover patch, you will seek another densely vegetated patch until you find one with a good supply of berries and fruits.
These scenarios also explain why the Gay Head cliffs area is such a great destination for birders. Migrants concentrate there for two reasons. Their next flight is across water, which they are hesitant to do during daylight because of those hawks. And all those thickets and scrubby woodlands contain a lot of food — berries and fruits — that the migrants depend on to power their continued migration.
Bird Sightings
Bob Shriber found a dickcissel in Aquinnah on Oct. 27. It is getting late in the season to still have a dickcissel around, maybe this one will linger longer and into the winter.
Ella Jernegan observed and photographed a small owl perched on a small post on Oct. 29. Is it a screech owl or a saw-whet owl? An online discussion about its identity followed, and we concluded that it was a saw-whet owl. This diminutive owl, smaller than a robin, is most common in the winter and its southward migration is now peaking. As its name suggests, its call is similar to the sounds of someone manually sharpening a saw.
Ned Robinson-Lynch observed a late-migrant osprey on Oct. 29, near the canoe slide at Sepiessa Point. This is another species that is lingering later into the season than normal.
Lanny McDowell visited the Gay Head cliffs on the morning of Oct. 30. Birds seemed a little scarce as his highlights included a Baltimore oriole and a northern mockingbird and a flock of common grackles.
Dark-eyed juncos are showing up more frequently now. Luanne Johnson observed them in her yard on Oct. 31, and I found a flock of six of them at the high school on Nov. 2.
On Oct. 31 I caught up with Anne Lemenager and Danny Whiting at the Oak Bluffs pumping station. Our highlights there include several bufflehead, 10 mallard, two black ducks and 15 American wigeon. The wigeon are the first arrivals of a flock that will be present there throughout the winter.
Speaking of bufflehead, they are becoming more common now, as a few can be found on most of our coastal ponds. The largest flock I have heard of to date is from Susan Straight, who observed a flock of 15 on Quitsa Pond on Oct. 30. More of them are undoubtedly on the way south, as they are a common winter resident.
On Nov. 1, John Nelson went to Squibnocket Beach and found the first northern gannets of the season. There were six of them flying by offshore. There also were 14 harlequin ducks and one great cormorant.
I went to the head of Lake Tashmoo just after dawn on Nov. 1 and flushed a black-crowned night-heron that then flew about a quarter mile up the pond before disappearing into the woods along the western shoreline. A belted kingfisher was hunting along the shore. And there were two Carolina wrens singing, one near the Tashmoo Spring Building and the other to the west on Tashmoo Farm. It has been a long while since I last heard two of them singing at the same time. Jacqueline Beauvais Cromwell had one show up in her yard on Nov. 1. They seem to be recovering from the mortality caused by last winter’s cold and snow.
Finally, a sad note from Nantucket. That island’s long time premier authority on birds, Edith Andrews, passed away on Oct. 31, the day after she turned 100 years old. She was amazing, one of the friendliest and most helpful people I ever met. All Vineyarders send their deepest sympathies to her surviving family and to the many others who were blessed to know Edith.
There are lots of birds around, so please get out looking for them, and be sure to report your bird sightings to birds@mvgazette.com.
Robert Culbert leads Saturday morning guided birding tours and is an ecological consultant living in Vineyard Haven.
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