We at MNHC (especially Jessie) have been eagerly awaiting the return of the osprey, particularly the pair that nests on the platform at the Osprey Stadium. We have a good view out of our north-facing windows, and Jessie can even see the nest from her window, with the help of binoculars. Last year, the osprey returned on March 25th. Last week Friday, on the 26th, a few of us went over to the osprey stadium to pull knapweed and other weeds from the area below the nesting platform. There was plenty of knapweed, but no osprey. None over the weekend. None on Monday or Tuesday. But today--today we saw a big, beautiful osprey circling over the river and McCormick Park, above the dusting of snow on the ground, beneath white clouds and blue spring sky.
We are very fond of the pair--we think they're the same birds, coming back year after year--that nests over at the baseball stadium. They have learned to put up with a lot: frequent summer games, cheering fans, and even fireworks (though they don't seem at all happy about those). At every home game, MNHC sets up an osprey information table and a spotting scope, so that baseball fans can learn a little about this lovely raptor, as well as take a peek at the chicks in the nest. (By the way, tabling at Osprey games is a great volunteer opportunity for those who are interested!)
Osprey (Pandion haliaetus) are found on every continent except for Antarctica, making them one of the most widespread birds in the world. One of the largest birds of prey in North America, it can be found throughout the continent (save for the farthest northern portions of Alaska and Canada). Osprey have dark brown uppersides, including rump and tail, as well as a dark wrist and secondaries underneath. The body and coverts are white; there are also patches of white on the primaries, though the wing tips are dark. Up close, one can distinguish the distinctive dark eye stripe and white cap. Osprey have long crooked wings, with an average wingspan of 63"; of the raptors in western Montana, only golden and bald eagles are larger. Their call is a short, chirping whistle, either single or in a series. Listen to it here.
Osprey can be found in riparian areas, particularly in those areas with open water that contains fish; fish account for 99% of the osprey's diet. The bird will hover high over the water, and then swoop down, diving feet first into the water to catch the fish. Osprey have specialized rough pads on the soles of their feet, which helps them to better grip the fish. After catching the fish, they carry it to a tree to eat, or take it to their nest to feed to their young.
Osprey build large, bulky nests of sticks high in snags or on top of human-made structures near water. In Missoula, osprey mostly nest on several specially-made platforms around the city. The female lays 1-4 eggs, which do not hatch all at once; the first chick may hatch up to five days before the last one. The first chick thus has the advantage, and will dominate its siblings, even taking most of the food that the parents bring. If there is plenty of food to go around, this isn't usually a problem, but when food is scarce, the younger chicks may starve. Last spring we originally counted three chicks in the osprey nest at the baseball stadium, but there were only two by mid-summer. Though we do not know for sure, this may have been a case of the youngest chick starving.
Now that the osprey are back--there are also reports that one has returned to the nest platform on Mullan Road--we encourage you to go out and enjoy them . . . and let us know if (and where) you see them!