There’s no shortage of studies demonstrating that conditions during one part of birds’ annual of breeding and migration cycle can affect individuals in subsequent stages — a phenomenon known as carry-over effects.
We usually think of a species as being reproductively isolated – that is, not mating with other species in the wild. Occasionally, however, closely related species do interbreed. New research …
I am lucky that one of the species of hummingbird I study, the Blue-throated Starfrontlet (Coeligena helianthea), occurs on my university’s campus in the mountains of Bogotá, Colombia.
One of the daily joys of summer is waking to the sounds of bird song. Those early morning bursts of singing herald the start of our days, for birds and people alike. If we listen carefully, though, the dawn chorus also reveals something about the state of nature.
The latest supplement to the American Ornithological Society’s checklist of North and Middle American birds is being published in The Auk: Ornithological Advances, and it includes several major updates to the …
The AOS Council is pleased to announce a new annual publication prize, the Wesley Lanyon Award. This new award will recognize the early-career ornithologist who authors the best synthesis/review paper on …
About 25 years ago, I started a research position at the Instituto de Ecología AC in Veracruz, Mexico. During my first explorations of the cloud forest there, I heard the marvelous sound that eventually became a key part of my work and that of my assistant Clementina González.
Scientists have long thought that for two related populations of birds to evolve into separate species, they needed to be completely separated. This usually means the kind of total separation produced by isolation on islands or by features such ice sheets, mountain ranges, or rivers. However, the complex distributions and migratory nature of many birds mean that long-term total separation of bird populations, long the assumption in speciation research, is actually not necessary for speciation to occur.
Many species of migrant songbirds have a reproductive strategy called protandry, where males arrive at stopovers and breeding sites earlier than females. Ornithologists believe that males do this because it increases their mating opportunities and reduces competition among males for high-quality nest sites. Although it’s a common phenomenon, the question of how males arrive earlier is still unanswered for most species.
In years when winter conditions are especially harsh, birds that depend on conifer seeds for food are sometimes forced to leave their homes in northern forests and wander far from …
