Status of the Cormorants of Great Salt Lake

Abstract

often be impossible to go further, but in many winter or summer falcon ranges, accurate identification of pellet material, at least to family or genus may be made, and not rarely to species or even subspecies. The bulk of the feathers in a pellet are usually from head, neck and breast. These feathers may be slightly altered in color, but apparently not in pattern, if any exists. Frequently the beak or claws or both are present and are useful in identification. A knowledge of local distribution and habitat will help narrow the field, as in mammals, and it should be remembered that coverhaunting birds are not ordinarily available to any falcon. Finally, at a given site there may be a dozen or so pellets of exactly the same color, size, and consistency. Two or three of these may be positively identifiable through beak, claws, primaries, etc. Since falcons so habitually pursue one species of prey at a time, there is an extremely strong likelihood that the beakless and clawless pellets of the lot represent the same species as the others, especially if from state of dryness and weathering they seem to form a compact age series. Similar deductions may often be made from the scales of reptiles, especially since the skin of one or more feet of a lizard may often be floated out of a pellet almost entire. Insects may be counted, and at least partly identified, by the very resistant mandibles, even if the rest of the head is broken beyond use. Other parts of insects in recognizable condition are of irregular occurrence in falcon pellets.