The split of Yellow Warbler into two species in 2025 (by eBird) brings a challenging identification issue into the mainstream. It is possible to identify most by plumage color (more details coming soon), but differences in the shape of body, wings, and bill provide more consistent clues for identification. Northern undertail coverts longer and fuller, […]
The two species of Yellow Warbler differ in structure Read More »
Possible? It might be, but most of the widely published “differences” are too subjective and/or too variable to be of any value. I dug into this a couple of years ago and discovered some details that seem more reliable, which are summarized in the one page file here (also as a pdf via this link:
Distinguishing Philadelphia and Red-eyed Vireos by song: Is it possible? Read More »
I put together this matrix of variation in breeding plumage Rose-breasted Grosbeaks, showing the differences between each of the four age-sex classes. In this species it’s relatively easy to distinguish males from females, a little harder to distinguish one-year-old males from older males, and nearly impossible to determine the age of females. As in many
Determining age and sex of Rose-breasted Grosbeaks in spring and summer Read More »
Stejneger’s Scoter is the Siberian counterpart of White-winged Scoter, only recently recognized as a separate species. The two species are very similar in all respects, and only adult males can be identified readily in the field. Stejneger’s is considered a very rare visitor to western Alaska, but my experience in Nome in 2021 suggests that
Finding and Identifying Stejneger’s Scoter in Alaska Read More »
No matter how serious you are about birding, or how much you want to see hawks, a Mourning Dove will always have a stronger interest in spotting them. Birds that are in mortal danger of hawk attacks have excellent eyesight and are constantly alert to any potential threat. It’s a safe bet that they will spot
Finding hawks by watching doves Read More »
By the end of February, even in cold and snowy Massachusetts, Red-tailed Hawks are courting and forming pairs in preparation for nesting. It’s common to see the male and female of a pair sitting close to each other in a tree, and this provides a very powerful clue to identification. Hawks are generally solitary and
Pairs as an aid to hawk identification Read More »
One of the biggest challenges of identifying a Cackling Goose is just finding one, especially in the east where the species is rare and occurs mostly as single birds (of the relatively large and pale Richardson’s subspecies) among big flocks of Canadas. The photos below show one Richardson’s Cackling Goose among Canadas. See if you
Can you find the Cackling Goose? Read More »
Most Passerines only hold juvenal plumage for a few weeks, quickly molting to a more adult-like plumage soon after they fledge and before fall migration. It’s a plumage that is seen almost entirely on the breeding grounds, but the breeding grounds (and fledging time) of many birds overlaps broadly with the fall migration of others,
Juvenal plumage of songbirds: Gray Catbird Read More »
The flippant answer is “…because they look alike”, and they can be very alike. Most of what you read about yellowlegs will tell you to look at bill length to distinguish the species. The bill of Greater Yellowlegs is actually longer (50 mm or more, compared to Lesser’s 40 mm or less) but birders deal
Why are Yellowlegs hard to identify? Read More »
Among the many benefits of paying attention to bird sounds is that they give you an insight into what the birds are doing. Through their songs and calls the birds announce not only their presence, but also what they are doing. One example is the mobbing of predators. Birds give alarm calls when they see
Understanding Alarm Calls of Birds Read More »