My natural history interests have expanded steadily over the years to include pretty much everything, plant, animal, or mineral. But birds were the group that first captivated me, an interest very much evident by the time I hit kindergarten. Closing in fast on age 68, it’s fair to say that I’ve paid at least a little attention to virtually every bird I’ve encountered in the past 60 years.
While I like a good rarity as much as the next guy, common birds also bring me joy on a daily basis. In particular, our local breeding birds are fun to watch and get to know. It’s a lively show. This year, our modest yard in Oak Bluffs has hosted four pairs of grackles in tall conifers on the edge of the yard, front- and backyard robins, a pair of chickadees finally using a nest box that has been hanging for nearly a decade, catbirds eagerly eyeing the ripening fruit on our blueberry bushes, song sparrows, and a pair of cardinals that is clearly nesting somewhere but I’m darned if I can figure out where.
June is a critical month for the Island’s breeding birds. Nearly every species that reproduces here hatches at least some of its young during this month. So like most of the Island, our yard has been raucous with squabbling adults and begging young.
There is a brutal side to it. Eggs or nestlings represent a protein source for anything that can eat them, and protein is a high priority if you’re trying to raise your own fast-growing young. So crows raid the grackle nests; grackles try to pluck eggs from blue jay nests; the jays harass the robins; and even the robins, which you might not think of as ruthless predators, will snag a meal from a song sparrow nest if they get the chance.
This all adds up to a month of high-stakes gambling for breeding birds. A nesting pair needs to cover multiple bases: incubating eggs, brooding chicks, foraging to feed themselves and their young, defending the nest against would-be predators. Often these goals conflict. A trip to forage by one adult leaves the nest lightly defended, with only one adult to protect against nest robbers. It’s not uncommon to see multiple crows or grackles work as a team to exploit such weakness, overwhelming the defense of a nest they’ve discovered by attacking simultaneously from different angles.
It’s interesting to note the varying ways different species resolve the tension between being highly secretive and protective, which guards the nest but requires sacrifice of time that might be spent foraging, and being less defensive, which increases the risk to your young but may make you a more efficient parent. There is no one right answer, in evolutionary terms. Some species lean toward caution, others toward a chancier emphasis on seeking food. Even within a particular species, individuals or pairs may stand out as more or less secretive than their neighbors.
Toward the relaxed end of this spectrum would surely be the chickadees that are nesting in a small nest box hanging next to our deck. The adult birds have had ample time to become accustomed to me and my activities. As year-round residents, these birds have observed me across many months, several seasons, and possibly more than one year. They may even have come to regard me as a resource of sorts, since I often leave a dish of fresh water on the deck railing for birds to drink or bathe in, and these chickadees frequently make use of this.
These birds haven’t exactly ignored me as they’ve nested, laid eggs, and begun feeding young. But if I stand or sit more than a few feet from their nest box, the adults will enter the box, feed their young, and depart with little regard for me. We’re not friends, exactly. But the birds have concluded that I’m not a threat, and that therefore there is no need to waste time and effort concealing the location of their nest from me.
The front-yard robins, meanwhile, wary to start with, have also evolved a measure of tolerance for my presence. Their typical food-delivery visits to the nest take place in stages, with the adult bird, food held in its beak, zigzagging through a succession of perches as it approaches the nest. From each perch, the bird scans the surroundings, undoubtedly looking for potential predators, advancing only when the coast is clear.
Early in their nesting cycle, I clearly registered as just such a threat: The adult would refuse to visit the nest as long as I was visible. But over time, the rules have relaxed, and while the adults still keep an eye on me, they freely visit the nest when I’m around, and forage within a few feet of me as long as I keep still.
In a few weeks, it will all be over, and the success or failure of all these hard-working breeders will have been determined. In the meantime, it’s a privilege to watch them balance the needs that demand their time and attention.