Eaglet trios: good things come in threes

In area bald eagle nests, young seven- to eight-week-old eaglets are peering out of their 90-foot-high aeries over some pretty spectacular landscape. Feathers are replacing their battleship-grey down, and growing flight feathers are visible. In an increasing number of nests, the grey fluff and brown feathers are more obvious; there is a trio of young instead of the usual average of two.

Bald eagle populations have been increasing in and out of the region, thanks to efforts of many agency and citizens’ efforts. Locally, NYS Department of Environmental Conservation data shows an increase of nesting pair, and over the past few years, there have been in increase of three young in a nest. This usually occurred in five to 10 percent of nests in the past. In 2008 however, nests along the main stem of the Upper Delaware River have shown a 33 percent incidence of three young in a nest. This year, ongoing young counts and nest surveys are hinting at more trios in nests.

When three young are in a nest, there is an increased chance that one will not survive. The hatch interval between the first and third egg can be over a week, and the youngest eaglet can be much smaller than the oldest. The smallest eaglet can be bullied out of its share of food, or otherwise injured in a sibling squabble. As the young grow, the four- to six-foot diameter nests turn from spacious to crowded, and an eaglet occasionally falls out of the nest. This region shows a very good survival rate for trio nests, however. This could be attributed to good food abundance, or lower stress due to disturbance. Anecdotally, it could be said that the “quality of life” factor is very good for the eagles here.