April 12 notes: we have a hatch!
Charlie Todd's wife, Barbara, saw a small head peak out from under the adult eagle's wing on Wednesday, April 12. Later, at least two little guys were briefly visible in the nest! As Charlie mentioned earlier, this is one of the most successful eagle nests on the coast of Maine, and they've done it again! One adult will brood the chicks almost constantly for the first few weeks because young eaglets are covered only by a light down coat. They are susceptible to cold and rainy weather as we are experiencing right now. Last year's heavy spring rains and exceptionally cold temperatures reduced nesting success statewide, but the population should recover quickly from these random events.
To give you an idea of what a hatchling looks like we've attached a picture of a day-old chick that Barbara raised in 1978. The egg came from a nest on Swan Island (Sagadahoc County) and unexpectedly hatched in an incubator following fostering of an eaglet there. The Swan Island eagles had not hatched their own egg in at least 20 years. Twice, we introduced an egg or eaglet from a captive breeding facility in Maryland to bolster eaglet numbers locally. This young eaglet was raised in captivity until 4 weeks old and then fostered back into another eagle nest where the adoptive adult eagles raised it to fledging!
Young eaglets can only eat very small items so the adults will tear up food into bite-sized portions and gently offer it to the chicks. As with many birds of prey, eagle chicks don't hatch at the same time so one eaglet is larger than its sibling(s). If food is scarce, the oldest eaglet outcompetes others for food and survives, while smaller sibling(s) may not. With ample food, all nestlings will fledge. Food availability has a great deal to do with nest site selection, especially during the nestling period. The presence of anadromous fish, such as alewives, often enhances brood size (the number of eaglets in a successful nest).
Management comments: Food quality is important during this early nesting period. Coastal eagles feed much more on birds, especially fish-eating birds such as gulls and cormorants, than do our inland nesting eagles, which eat a much higher proportion of fish. The result is that our coastal eagles have a greater chance to accumulate contaminants such as DDE, PCPs and mercury. Luckily DDE is rapidly disappearing but the other chemicals are still present in our environment. -- Bucky Owen, University of Maine emeritus