Thursday, May 23, 2013

By E. Vernon Laux
Published: June 11, 2009

The natural world is bursting with the activity of breeding birds. The serious business of reproducing the species, essentially passing on the most successful genetic material that belongs to living birds, is what is now going on with almost all birds in the area. Courting, building a nest, laying eggs, incubating, feeding young, and surviving to breed another day is what the next couple of months are all about for Island birds.

This female osprey was most unhappy about intruders near her nest pole. Taken last year when the young were being banded, she shows a dark "necklace" or breast band. Photo by E. Vernon Laux

Despite great changes in human habitation and density on the Vineyard over the past decades, it still retains much protected land and a generally rural character away from down-Island town centers. This is very good for nesting birds. The Island has prodigious numbers of eastern towhees, gray catbirds, common yellowthroats, ovenbirds, and yellow warblers - to name a few species - that far exceeds in density what may be found on neighboring Cape Cod.

A worthwhile experiment for anyone interested in birds, and one worth repeating, is to rise at 4:30 am on a morning with little wind, no precipitation, and hopefully a sunrise, and proceed out to the State Forest or a nearby Land Bank property. Upon stopping your car or bicycle - stand still and regulate your breathing so that it is not a distraction and listen for a good three minutes.

Take a deep breath and be amazed at the numbers of birds singing - and their volume. This dawn chorus is a remarkable event that draws the listener into a deep appreciation of the mysteries of life, living, and the role birds play in the grand scheme. For terrestrial-based life forms that get up and go to work every day at a certain time or observe whatever schedule one observes, it offers a glimpse into an entirely different world.

These small feathered creatures, far and away the most mobile animals on earth, traverse distances unthinkable for a bipedal creature, especially before the advent of modern technology, and live life at a pace we cannot even imagine. The breeding season is draining, physically demanding, and dangerous, as birds are forced to remain in one place, their nest site, giving predators that at other times of year have no chance of capturing such alert, active animals, an almost level playing field. They have a far greater chance of capturing a bird in a nest now than at any other time.

This is partially overcome by the sheer numbers of birds breeding and each species' synchronicity. Nest building, the laying of eggs, hatching of young, etc., happen more or less simultaneously among all members of the same species, essentially overwhelming the predators' ability to get more than a small percentage of the population. They can only eat so much. The case of domestic cats is something else entirely and is a devastating, human-inspired impact on native songbirds.

Vagrancy

For a variety of reasons that one can endlessly speculate about, birds wander widely during the breeding season. While there are not many birds doing this, there are enough to provide a thrill to birders. Some are immature birds, sub-adults, that are not yet ready to breed and many fly a long way from their normal range. The reasons why a bird would wind up hundreds or thousands of miles from where it usually occurs are impossible to say.

There have not been any reports of albatrosses this year from nearby waters. Almost yearly in late spring reports of an adult yellow-nosed albatross had been sporadic but regular from all over the eastern seaboard. These birds breed on a few islands in the southern hemisphere where the seasons are reversed from the northern hemisphere. There are no albatrosses in the North Atlantic Ocean except as vagrants.

These birds depend on strong winds. Specialized gliders that cruise around the southern oceans with great regularity and ease, they are designed to take advantage of wind currents using little to no energy. Once an albatross crosses the equator and the equatorial doldrums it may not be able to return south. Perhaps the yellow-nosed albatross crossed this region in front of a brewing hurricane, aided by the outer bands of circulating winds, which only very rarely blow in the opposite direction.

At any rate, some birders have proposed that there were multiple yellow-nosed albatrosses roaming around the northwest Atlantic, while many other ornithologists believed it was the same bird. Sadly, this individual bird crashed inland and was picked up in a field. After extensive rehabbing it was released back into the wild fitted with a satellite transmitter only to be picked up again inland. It was released again well offshore from Cape Cod. The bird was then found dead in Barnstable Harbor a couple of weeks later. There have been no further sightings since this bird's demise, lending much credence to the one-bird theory.

Until next time - keep your eyes to the sky.