Saturday, August 23, 2008

Farm Bulletin: Feathered Friends

Anthony and Carol Boutard have taken care to nurture the native inhabitants of Ayers Creek Farm in Gaston, and have even changed some of their farming practices to enhance the habitat of the birds and insects they share the land with.

At the center of the farm is small canyon bordered by a roughly 20-acre oak savannah. It took three years to clean out the old fencing, water heaters and machinery that were pushed over the edge with a Cat, all anchored in place by a thicket of wild blackberry. Ten years later, yanking out errant blackberry canes remains a springtime chore. But now grasses and seedling oaks are retaking the ground, providing forage and cover for songbirds and supporting prey for raptors. As the grasses and forbs increase in extent and complexity, so has the bird life.

Last year, as some may remember, a pair of acorn woodpeckers arrived in June, and raised a couple young. Acorn woodpeckers are communal birds, and cooperate to build granaries of acorns in dead limbs and trees. The silvery, muscular limbs and trunks of the dead oaks are now pockmarked with holes, each containing a carefully cached acorn. The trees are beginning to take on the distressed look, not so long ago the must have of the fashion industry. Last month, a reedy call announced that a new generation of acorn woodpeckers had fledged. The four adults are tending to the two young birds, demonstrating the intergenerational cooperation that makes these birds noteworthy. During the summer, the birds are mostly insectivores. Their behavior is similar to a flycatcher. They sit on a limb until an insect passes by, and then they give chase. A successful foray initiates feverish begging from the youngsters. This sit-and-chase behavior is called "hawking," and is also practiced year-round by the Lewis's woodpecker.

Last year, being the year of the woodpecker here, a Lewis's woodpecker showed up in December. With its deep green back, and its stunning dark rose breast, it was a welcome visitor. The poor dear really wanted to stay, and excavated a nest cavity. When its oneness became too much to overcome, it left, probably back to the Gorge where the species normally resides. Starlings promptly grabbed the new digs. The Lewis's was in an area outside of the acorn's territory, so it was left alone. A pileated woodpecker showed up a couple of times in the heart of the acorn's territory, and retreated after an hour or so of their fury. They defend their granaries aggressively against potential thieves, and even immature acorn woodpeckers are not allowed near the food stores.

With the acorn woodpeckers, there is a constant conversation among the group. During the day it is a "kweck" call that probably gives the bird's location. The tempo and frequency varies a bit, indicating other information is being conveyed. Their call changes sharply to an alarm when a hawk is nearby. They ignore the long-eared owls the occupy the same territory. There is also a separate call to action when a potential thief, such as a jay, starling or a pileated woodpecker, is nearby. Towards dusk the family carries on a comforting, almost melodic, goodnight conversation back and forth that lasts almost 30 minutes. Kind of a cozy, avian Walton family moment.

Top photo by Greg Gillson. Photo, lower left, from Wikipedia.

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