Mallards—Where Have All the Males Gone? With the songbird breeding season winding down, let’s talk about waterfowl for a moment. The Mallard is the most familiar and widely distributed duck in North America. Ducks are generally classified in two ways, based how they forage for food in the water. “Dabbling” ducks, such as the Mallard, feed on the surface or “tip up,” with their tails in the air and their heads underwater, to grab vegetation below the surface. “Diving” ducks such as mergansers and grebes dive and chase…

House Finch—The Ubiquitous Fruit Biter Among the first native songbird species to make an appearance at Greenwood during baby bird season, House Finches are a very common sight in Colorado. They can be found in every county and they breed in all but 3 high mountain counties here. In 2014, Greenwood took in 85 members of this widespread species: 66 hatchlings, nestlings and fledglings and 19 adults. Originally, House Finches resided only in Mexico and southwestern U.S. But they were illegally sold as caged birds in the East…

Swallows—Life on the wing North America has 9 swallow species; 6 species breed regularly in Colorado. The common name of “swallow” derives from the Anglo-Saxon “swalewe,” which described this group of birds. These amazing fliers feed almost exclusively on aerial insects. All are insectivores and most arrive Colorado in mid-April, heading back south for the winter by mid-September. Below are brief descriptions of the 4 species Greenwood admits most often: Barn Swallow, Tree Swallow, Violet-green Swallow, and Cliff Swallow. The Barn Swallow is the most abundant and most…

Hummingbirds—It’s Not That They Don’t Actually Know the Words… I write about the natural history of birds for a variety of audiences. When I set out to write about a species, I think “What is interesting about this species?” With hummingbirds, though, what isn’t interesting about them? The smallest of all birds, hummingbirds weigh between 0.1 and 0.3 ounces (2.5 – 8 grams)—or about the same as 5 – 15 M&Ms for most of the hummingbirds we see in Colorado. Probably the most striking aspect of hummingbirds is…