ID Tips for Those Winter Predator Hawks
(Jeff Mc Partlin, an experienced local falconer and raptor "guy", kindly offered some tips to quickly identify those predator hawks lurking about our feeders)
I might offer a couple of tips as to how one might quickly identify the small raptors that frequent Great Falls and surrounding areas during the winter months. First of all, MOST kestrels migrate out of our area during and shortly after the Swainsons Hawks leave in September. The kestrels start to return earlier than the Swainsons Hawks. They generally start to show up in the latter part of March, whereas the Swainsons usually begin to arrive back around April 20th. The handful of kestrels that I see now, frequenting the power lines between where I live and town, and that remain throughout the winter are USUALLY adult males. Therefore, by process of elimination, one can generally assume that the raptorial visitor to the back yard feeder is PROBABLY not a kestrel. However, if you notice that the little raptor is resting on a wire or tree branch, and not infrequently twitching its tail up and down, it could be a kestrel as Merlins and Sharp-shinned Hawks DO NOT make up and down 'jerking' motions with their tails when standing at rest.
Two other species probably represent the bulk of the predatory attacks that are witnessed in the local back yards as well as in down town areas. These are the Richardson's Merlin and the Sharp-Shinned Hawk. MOST of the Coopers Hawks also vacate the area during the winter, with some few exceptions. Therefore the hawk observed attacking the small birds or feeding off of one during the winter months are MORE THAN LIKELY a Merlin or a Sharp-shinned Hawk. The fact that either or both species can show up on the same day at the same location is probably well known to many of the club members. When the song birds show up in numbers, nature is ringing the dinner bell for these two small hawk/falcon species.
O.K., here are a couple of quick tips. The Sharp-shinned Hawk will ALWAYS have yellow, orange or red eyes...depending on age. Sex does not have anything to do with the eye color. The Merlin will ALWAYS have dark brown, nearly black looking eyes. The wings of the Sharp-shinned Hawk are rounded whereas those of the Merlin are long and pointed. A very good clue is that the Sharp-shinned Hawk ALWAYS has dark bands on the tail, and not white ones. The Merlin has nice, clearly identifiable white bands on the tail. Immature Merlins of both sexes have brownish colored backs and streaked chests. The adult female Merlin also is brownish colored on her back. The adult male Merlin has a beautiful, light blue colored back . This is where some confusion may occur. Both adult male and female Sharp-shinned Hawks have a bluish-gray back whereas the immature Sharp-shinned Hawks of both sexes have a brownish colored back as do the immature Merlins of both sexes and the adult female Merlins.
To really help pin down what your binoculars or spotting scopes are showing you I would suggest looking at the following: 1.) The color of the eyes. 2.) The color of the bands on the tail (all dark bands are Sharp-shinned Hawks as well as their large cousins, the Coopers and Goshawks) . The Merlins are readily distinguishable from the similar sized Sharp-shinned Hawk by the white bands on the tail. Finally, if the observation is of any duration, you will see the long, pointed wings of the Merlin falcon as opposed to the short, rounded wings of the Sharp-shinned (accipiter) Hawk. I hope these few tips might be of some assistance.