(Click image for a larger version)
The new Crossley guide hits bookstores this week, bringing Crossley’s unique approach to the task of helping you identify more raptors—whether they’re familiar, unfamiliar, faraway, backlit, immature, adult, light-morph, dark-morph, soaring, hovering, or sitting.
With raptors for a subject, this guide concerns itself with far fewer species than 2011′s Crossley ID Guide: Eastern Birds, and the authors have used the extra room well. Crossley has always wanted readers to engage with his books—to puzzle over each plate’s many shapes and patterns as much as they read the ID tips at the bottom of the page.
This new book adds even more of an ID workbook feel than the last guide. Interspersed with the book’s 67 two-page identification spreads are 15 “mystery” plates that challenge readers to put the book’s advice immediately to use in working out identifications.
As an example, check out the one above: you’re out birding on the central prairies, and a host of buteos are circling in the sky. Which is which? Take a close look and see if you can identify each numbered bird (for the smaller specks, try clicking for a larger image). Then scroll down for the answers, provided by Crossley’s coauthor Brian Sullivan, who is an eBird project leader and raptor expert.
Scroll down when you’re ready to read Brian’s answers:
Answers to the Quiz: by Brian Sullivan
(Tip: right-click on the image above and select “Open link in new window.” Then you’ll have the image next to you as you read the answers instead of scrolling up and down.)
How many species? There are four species in this composite photograph: Ferruginous Hawk, Red-tailed Hawk, Swainson’s Hawk, and Rough-legged Hawk. These are all buteos—large, long-winged birds with rather short tails. These characteristics help them soar efficiently over open country; several species also regularly hover or kite. They have shorter tails than accipiters and broader, rounder wings than either falcons or kites. Bear in mind that most buteos can occur in several color patterns: “light-morph” (generally more common) and “dark-morph” (less common), as well as occasional intermediates.
So which is which? Next, to identify these buteos, focus on subtleties of shape and broad plumage patterns. (Flight style is also key to identification, but that is difficult to discern from still images.) Here are the points to look for in each example:
1. Adult light Ferruginous Hawk. Snow-white underneath with rufous leg feathers, underwing mottling, and upperwing coverts. Light Ferruginous Hawks have long, rather pointed wings and are overall very pale.
2. Adult light Red-tailed Hawk. Pale underneath with dark patagial bars and belly streaks. Virtually all light Red-tailed Hawks have these dark patagial bars (the leading edge of the underwing). Note rufous tint to underside, dark trailing edge to wings, and reddish tint to tail; these denote an adult.
3. First-summer light Red-tailed Hawk. Not all Red-tailed Hawks have red tails! First-years have brown, banded tails. They molt into the red tail during the first summer, as shown in this bird. Brown overall on top. Broad wings with new, darker inner primaries, outer primaries showing first-year paleness, which can look like a window in the wing. Brownish, faintly banded tail with new, reddish adult feathers.
4. First-year light Red-tailed Hawk. Pale underneath with dark patagial bars and bellyband. Lacks the buffy or rufous tint to the underbody, dark trailing edge to the wings, and reddish tail of adult. Shows translucent primaries.
5. First-year dark western Red-tailed Hawk. Broad, somewhat long wings in a full soar. Note that the uniformly brownish body and underwing coverts is an uncommon plumage. Lack of defined trailing edge to wings and reddish tail denote a first-year bird.
6. First-year light western Red-tailed Hawk. Pale underneath with dark patagial bars and belly streaks. Note: translucent primaries and plain buffy coloration denote a first-year bird.
7. Adult intermediate Swainson’s Hawk. This bird shows long, pointed wings in a shallow glide. Swainson’s Hawks usually show pale underwing coverts contrasting with dark grayish flight feathers. This one also shows a dark chest bib and paler belly. Many intermediate adults are mottled on the belly.
8. Adult light Red-tailed Hawk. Pale underneath with dark patagial bars, belly streaks, and reddish tail. Somewhat long but broad wings.
9. Adult dark Ferruginous Hawk. Dark underneath with whitish, plain flight feathers, and minimal dark on wingtips. Wings are long and tapered, but unlike dark Swainson’s, Ferruginous have very pale flight feathers. Dark trailing edge to the wings, rufous overall body plumage with whitish throat, and lack of dark on the tail tip denote adult.
10. Adult female light Rough-legged Hawk. Pale underneath with blackish belly and wrists. Dark trailing edge to the wings and defined dark tail tip denote an adult. The single dark tail band, complete bellyband, and wrist patches denote a female.
11. Adult “Krider’s” Red-tailed Hawk. Pale and nearly unmarked underneath with minimal dark on patagials, reddish and whitish tail, and dark trailing edge to wings. Broad wings slightly tapered in shallow glide is classic Red-tail shape. Krider’s is a pale subspecies of the Red-tailed Hawk that breeds mainly on the northern Great Plains and winters on the southern Great Plains.
12. Third-year light Swainson’s Hawk. Pale underside with dark bib and flight feathers with darker trailing edge to wings and tail. Bib is near complete, and paler outer primaries help denote age. Unlike many buteos, Swainson’s takes three years to acquire full adult plumage. This summer bird is in the process of molting into its adult plumage.
13. First-year light Rough-legged Hawk. Pale underneath with solid blackish belly and wrists, and buffy, unmottled underwing coverts. Dark trailing edge to the wings is ill defined, but appears to have a dark tail tip. Translucent primary panels somewhat visible. First-years and adult females can be difficult to tell apart.
14. Adult light Ferruginous Hawk. Snow-white underneath with rufous leg feathers, underwing mottling, and minimal dark on wingtips. Wings are long and lack bulge along secondaries, body is robust. Compare shape with other light buteos on this page.
15. Adult female light Rough-legged Hawk. Most light Rough-legged Hawks are easily identified by the dark belly and wrist patches that contrast with the overall pale underparts. This is especially true of adult females and immatures. The dark trailing edge to the wings and defined dark tail tip denote an adult. The single dark tail band, rufous underwings, complete bellyband, and wrist patches denote a female.
(Image courtesy Princeton University Press.)