I filmed this Broad-winged Hawk in Biddeford, ME on April 27, 2014.
Note: This is the first in a series of short video clips of New England inhabitants. I hope you enjoy this mid-week meditation.
I don't have to tell you what kind of bird this is. Adult Bald Eagles are massive raptors with wing spans between 6 and 7 feet. In flight, their brown bodies can appear almost black, but their head and tail feathers are a clean white. What you may not know, is that Bald Eagles don't start out looking like this. According to various sources, it takes at least 4 years for Bald Eagles to obtain full adult plumage.
Immature birds have variably mottled wings and lack the distinctive white head and tail of adults. 1st-year birds (like above) have dark bellies with obvious white wing pits. 2nd-year birds (below) have lighter bellies and dark heads. 3rd-year birds (not pictured) are similar, but typically show more white in the head.
The 4th-year bird below shows limited white wings spots, and a mostly white tail framed with brown.
Feather color aside, immature Bald Eagles are similar in structure and size to their parents and show the same orange legs and large, hooked bills.
Note: The ages of the above birds are my best guesses -- if you have a different opinion of any of these birds, I'd love to hear it. The birds were photographed in mid-February in Bath, Maine.
Red-tailed Hawks are the most common soaring hawk in New England, but in some areas Red-shouldered Hawks are also quite common. A reliable way for me to tell them apart is by ear. Red-tails give a loud keeeeeeerrrr call, which lasts 2-3 seconds, while Red-shouldered Hawks give a shorter kee-aah call, which is typically repeated several times in quick succession.
Lacking audio signatures, these birds can be separated by appearance. If you notice a large soaring bird who lacks a red-tail, check near the wing tips for translucent arcs (which appear as light patches in the photos, but are often more see-through in person). While not always obvious (lighting can be a factor), these field marks (called windows) are a good clue that you've spotted a Red-shouldered Hawk.
In early January, I observed a pair of Red-tailed Hawks soaring over a large field in Wrentham, MA. The birds were fairly easy to tell apart, as one had a noticeable gap in her primary wing feathers. Based on size – female raptors are as much as one-third larger than males – I figure that this larger bird is a female, and the smaller bird a male.
The above and below photos capture the mid-air talon drop display of the presumably male bird, which according to the Stokes Guide to Bird Behavior: Vol 3 is a visual display employed during courtship rituals and territorial confrontations. According to Stokes, if the display is territorial in nature, it will be followed by one bird leaving and one bird remaining on the territory. In this case, both birds flew out of view, so I can't say for sure, but I suspect these two hawks are a pair.