Birds : Sensing the season change
By E. Vernon Laux
Published: March 4, 2010
Spring manifests its approach in a variety of ways. While its official arrival is still a ways off on the calendar, the inhabitants of the natural world are behaving as if summer is just around the corner. As the days continue to rapidly lengthen, birds' endocrine systems increase production of the hormones necessary for breeding, which alters both the way they look and act.
American robins are on the move. There are already reports of them attacking their reflections in windows, which they do when defending their territories. Click on photo to enlarge. Photo by E. Vernon LauxThe excitement builds rapidly in March, as we await the arrivals of not only the first returning osprey (quite likely in about 10 days) but also green-winged teal, killdeer, tree swallows, eastern phoebes, many more blackbirds. In addition, a large increase in bird song accompanied by displays of courtship behavior in resident birds make it clear that spring has slowly started. Never arriving fast enough, it takes its own sweet time.
The dance, both terrestrial and aerial, of the American woodcock is performed at dawn and dusk on calm evenings from now thru late May or early June. This performance can be heard and seen in all island towns. Naturally, some places are better than others. The best places will have an open field surrounded by woodland with little disturbance. However, the birds get so fired up in the spring, when many of them are just practicing before their arrival at their breeding area, that they will do their thing on ball fields and many other sub prime locations for the next few weeks.
The call of spring peepers, the small tree frogs that are in almost every small pond and stream on the Island, is about to start. Expect to hear the din of these little creatures virtually everywhere at dusk in a week or two. For the size of these frogs - a mere inch and a quarter or so long - they reach monster decibel levels.
Also predictable is a huge uptick in wood and deer tick activity (pun intended) over the rest of this month and continuing into July. These little blood-suckers are only loved by researchers who study them. They are most active on the Island from about mid-April thru mid-June when it is hard to go anywhere there are birds and not get many of these little nuisances all over one's legs. A thorough daily tick check becomes essential and will prevent most problems.
Bird song continues to increase in frequency and volume on a daily basis. An early morning walk will reveal the relative abundance and density of many birds that will be nesting in the neighborhood. Males of many resident species are staking a claim to a particular territory hoping to win a receptive female that admires his claim on a piece of local turf. Mate selection is driven by what particular real estate a male lays claim to. In other words it really is about location, location, location.
Northern cardinals are especially noticeable at this season as the males become vociferous in the extreme. These medium-sized, brilliant red, crested birds with black faces are widespread on the Vineyard and familiar to most. While both males and the much drabber females are easily recognizable when seen, the species song remains a mystery to most. This is one mystery that is easily remedied.
In most areas of the Vineyard right now, cardinals, along with resident Carolina wrens, are the loudest and most persistent birds singing in the morning and again late in the day. The song is a loud clear whistled two syllable slurred note lowering in pitch. The song variously described as what-cheer, cheer, cheer, etc. or birdie, birdie, birdie, etc.
Bird song is notoriously hard or impossible to describe in words, but don't let that discourage you. Armed with binoculars, head out into the neighborhood and find the loudest bird singing. The male cardinals stand out like light bulbs at this time of year as they whistle away loudly from the top of some tree or shrub.
Once located, take down the binoculars and revel in listening pleasure, adding this song to the data base in ones brain. Newly arrived migrant songbirds, red-winged blackbirds and common grackles, seemed to be singing and squawking from nearly every treetop this past week. Song sparrows have begun singing well before sunrise.
The rather innocuous disappearance of wintering sea ducks has already begun to happen. They just sort of fade away with little fanfare. In fact if one does not put a spotting scope on the water at least once a week it is a complete nonevent. Common goldeneyes are already thinning out as are long-tailed ducks. Both get much harder to find by the end of the month. Bufflehead numbers have increased, as migrants from further south have arrived and are waiting with the others to push farther north at the first opportunity.
The seasons are changing, inexorably, pushing and pulling, in fits and starts, and all the inhabitants of the natural world are poised to make the most of it.
Until next week - keep your eyes to the sky!
