Raptor Essentials Flashcards
Learn to appreciate and recognize all the clues that go into identifying raptors and hawks, from shape, size, and behavior to color patterns, habitat, and more.
What TWO cardinal rules can you apply to make raptor identification easier?
- Identify to which broad group it belongs first; and then narrow it down from there
- Find three or more clues; don’t fixate on any singular trait
BONUS: And in situations where you’re looking at a sky bustling with raptors (such as during migration), focus on identifying one bird at a time, rather than getting overwhelmed.
That said, raptors seldom gather together in large groups so you won’t often be faced with this kind of situation.
When observing raptors, we try to look for THREE clues to support an ID. What are the SEVEN “clue categories” in which this information can be found?
Actually, this tactic applies to identifying ANY bird in the field.
- Size - how big is the bird relative to widespread species like American crows or Canada geese?
- Shape - how long, broad, or prominent are the wings, tail, and head relative to the body?
- Color patterns - what is the distribution of light and dark on the wing, head, tail, and body?
- Markings - are there any noticable patches, streaks, or barring anywhere on the bird?
- Behavior - what are the bird’s ideosyncracies, flight style, and hunting technique?
- Habitat - where is the bird seen? In a desert, urban area, forest, open grassland, or road side?
- Calls - What sound does the bird make?
What are the THREE most important clues for identifying raptors?
- Shape
- Behavior
- Habitat
It’s not that size, markings, patterns, or calls are not important; they too provide valuable clues. But shape, behavior, and habitat convey the MOST information within the shortest amount of time, allowing us to very quickly discern the subgroup to which a raptor belongs. From there, it is a matter of deciding between a few species, rather than a few dozen species.
What are the SEVEN sub-groups of raptors in North America?
- Vultures
- Eagles
- Buteos
- Accipiters
- Kites
- Falcons
- “The Misfits”
These sub-groups aren’t strictly divided along lines of taxonomy (relation). Rather, they have been arranged according to shape.
The shape of a bird is one of the first things you notice about it, which will help you quickly discern into which subgroup it belongs. Once you know a raptor’s subgroup, your choice becomes narrowed down to just a handful of birds.
What is meant by the term “fingers” in raptor anatomy?
The elongated primary feathers that extend from the end of the wing.
Also called “emarginated primaries”
Photo by Paul Danese
The “fingers” allow air to pass through the end of the wings, which adds extra lift to their flight, while reducing drag. This is important for large, heavy raptors that spend a lot of time in the air soaring, searching for food, like vultures and eagles.
You can consider emarginated primaries a unique flight optimization that reduces the effort it takes to soar, thereby allowing raptors to conserve energy.
How can you deduce the relative size of a raptor when there aren’t any other raptors around to compare it to?
Compare it to the size of a common “yardstick” bird, like an American Crow or Canada Goose.
Photo from Wikipedia Commons
Most raptors are somewhere between the size of an American Crow and Canada Goose. A Cooper’s Hawk, for example, is about the same size as an American Crow (although females are larger).
Sharp-shinned Hawk, which look very similar to Cooper’s Hawk, are smaller than an American Crow; about the size of a Blue Jay. Understanding this fact will help you tell the difference between the two in the field, which illustrates the important role that relative size plays in raptor ID.
American Crow and Canada Geese are very common so even if there isn’t one in the field for direct comparison, chances are you’ll have a rough estimation of their size in your working memory.
What FOUR key aspects of shape are most useful to note when you’re looking at a raptor?
- Wing shape
- Tail shape
- Proportions
- Perched silhouette
All raptors have short, hooked bills, strong wings, and moderately long legs. Wing and tail shape, on the other hand, show a lot of diversity between the raptor subgroups, which is why they provide helpful clues for identification.
The proportions—relationship between wing, body, head, and tail size and length—are also useful, as is the silhouette of the bird when perched on a power line or tree branch.
What are SIX useful descriptors for wing shapes in raptors?
- Rounded
- Pointed
- Broad
- Narrow
- Short
- Long
- Rounded looks somewhat like a hand; with 4-5 feathers extending out like fingers.
- Pointed is where one feather clearly stands out as the longest.
- Broad and narrow refer to the width of the wing from the leading edge to the trailing edge of the wing.
- Short and long refer to the length of the wing from the proximal end (closest to the body) to the distal end of the wing (furthest from the body).
What is the difference between emarginated and closed wings?
- Emarginated wings are rounded, with clearly defined “fingers”.
- Closed wings are pointed, without clearly defined “fingers”.
What caveat should you take stock of when assessing wing shape?
Wing shape can change quite dramatically depending on how the bird is flying.
For example, when a hawk flies fast, it bends its wings back and the previously visible rounded wing tips can appear more pointed.
What are SIX useful descriptors for tail shapes in raptors?
- Long
- Short
- Notched
- Square
- Rounded
- Pointed
Just remember that, similar to wing shape, tail shape changes depending on whether the feathers are fanned out or not.
True or false?
A square tail can look rounded when fanned out.
True
When spread out, a Cooper’s Hawk’s tail appears rounded but when furled, it look more square.
What do we mean when we discuss the proportions of a raptor?
The size relationship between the wings, body, and tail.
- Red-tailed Hawk have moderately-long wings and short tails relative to their head and body.
- Cooper’s Hawk have short wings and a long tail relative to their head and body.
- American Bald Eagle have long wings and a short tail relative to their head and body.
By paying attention to raptors’ proportions, we visually capture clues that can help us narrow them down into their subgroups and perhaps even further into their species.
Describe the size proportions of this Golden Eagle using the descriptors mentioned in earlier flashcards.
Divide your descriptors between the wing and tail shape characteristics.
Photo by Giles Laurent
The wings are very long, broad, and rounded with emarginated tips.
The tail is short and rounded.
Describe the size proportions of this American Kestrel.
Divide your descriptors between the wing and tail shape characteristics.
Photo by Charles J. Sharp
The wings are long and narrow, with pointed tips and little emargination.
The tail is long and notched.
Describe the size proportions of this Northern Harrier.
Divide your descriptors between the wing and tail shape characteristics.
Photo by Wildreturn
The wings are long and medium width. The emarginated tips are visible but much more pointed because the wing is bent back.
The tail is long and notched.
What do we mean when we discuss the posture of a raptor?
The way the bird holds itself when perched.
Image Source: Rhododendrites
Most raptors perch in an upright position compared with other birds, which perch with their bodies at a 45 degree angle.
BUT there are some exceptions to this upright posture that can provide helpful clues for ID.
Which TWO raptors don’t typically have an upright posture when perched?
- Osprey
- Turkey Vulture
Image source: Wikipedia Commons
These two birds perch with their bodies held at more of a 45 degree angle.
When a raptor is perched, what important clue relating to wing and tail length should you look for?
The length of tail that sticks out from underneath the folded wings.
(Image source: Wikipedia Commons and Iwolfartist respectively.)
For example, Sharp-shinned Hawk and Merlin are two similarly-sized, similar-looking bird-eating hawks that can be difficult to tell apart, especially in flight.
When perched, however, the Sharp-shinned Hawk’s much shorter wings leave much of the long tail exposed, while the Merlin’s long wings cover most of the tail, leaving only a short segment exposed. This clue can help you tell the two species apart.
What TWO features of a raptor’s plumage can create patterns that are very important for identification?
The presence and location of white and dark (patches) on its body, such as the rump, wings, tail, and head.
Photo by B.K. Leach
The adult Bald Eagle is another obvious expression of how white on a bird can help you make a confident ID! (It has a bold white head and tail.)
The primary and secondary feathers make up a raptor’s flight feathers, while the underwing coverts and patagium make up a raptor’s wing linings.
Understanding the different parts of the wings will help you look for color patterns and markings, and have the vocabulary to distinguish between them when making an ID.
Ask yourself: What color are the flight feathers and what color are the wing linings? Are they the same throughout or do they contrast with each other?
What is the most useful marking to look for when identifying a raptor?
Barring
Which can be on the tail (Cooper’s Hawk), chest (Red-shouldered Hawk), or wings (Peregrin Falcon).
What is the difference between barring and streaking?
Barring refers to markings that run horizonally across a raptor’s chest or tail, while streaking refers to markings that run vertically down a raptor’s chest.
Interestingly, some raptors like Peregrine Falcons and Red-Shouldered Hawks have streaking when they’re juveniles, which then become barring when they mature. So the presence of barring and streaking in certain species can also tell you about their age.
Name the anatomical parts on this Peregrine Falcon.
Photo by Mykola Swarnyk
Name the anatomical parts on this Red-tailed Hawk.
Photo by Susan T. Cook
Why are habitat and range important factors to take into account when identifying raptors?
Raptors tend to be habitat specialists, so where you see them provides valuable clues to their identity.
What are the FIVE overarching habitat types you will find raptors in?
- Open country
- Forests
- Wetlands
- Deserts
- Urban areas
Each of these habitats is preferred by certain raptors, although many raptors can be found in a mix of these habitats, too. For example: Red-tailed Hawk can be found in just about all of them!
What are some examples of raptors that prefer open country habitats?
Open country habitats include farmlands, prairies, grasslands, roadsides, and marshes.
- Red-tailed Hawk
- Ferruginous Hawk
- Swainson’s Hawk
- Gyrfalcon
- American Kestrel
- Golden Eagle
The Red-tail Hawk and Swainson’s Hawk are the most common pole-perching raptors in North America.
There are many other raptors that can can be found in open country but these are just some examples.
What are some examples of raptors that prefer forested habitats?
Some are almost never found outside of these environments, except for during migration.
- Broad-winged Hawk
- Red-shouldered Hawk
- Gray Hawk
- Sharp-shinned Hawk
- Cooper’s Hawk
- Northern Goshawk
Most of these birds have relatively short, broad wings and long rudder-like tails for manoevering through heavily-treed environments, although this is most pronounced in the Accipiters (Sharp-shinned Hawk, Cooper’s Hawk, and Northern Goshawk).
What are some examples of raptors that prefer wetlands habitats?
- Bald Eagle
- Osprey
- Northern Harrier
- Hook-billed Kite
- Snail Kite
Bald Eagle and Osprey eat fish; Hook-billed and Snail Kites eat water snails; and Northern Harrier hunt for waterfowl over marshes.
What are some examples of raptors that prefer desert habitats?
- Golden Eagle
- Turkey Vulture
- Harris’s Hawk
- Red-tailed Hawk
- Zone-tailed Hawk
- Prairie Falcon
Harris’s Hawk and Zone-tailed Hawk are true desert specialists, while Red-tailed Hawk, Turkey Vulture, and Golden Eagle can be found in a mix of other habitats.
Being habitat restricted means that these two raptors are also range restricted.
Again, there are other raptors that can can be found in desert country but these are just some examples.
Give some examples of raptors that do well in urban habitats, like towns and cities.
- Peregrine Falcon
- Red-tailed Hawk
- Cooper’s Hawk
- Merlin
Peregrine Falcon do well in urban areas because the tall buildings and bridges they nest on mimic the cliffs that are their natural nest sites.
What FOUR aspects of a raptor’s behaviour can help you identify a bird?
- Flight style
- Foraging method
- Sociability
- Bobs & twitches
What are the TWO major flight styles of raptors?
Soaring and direct flight
If a raptor is riding the thermals, gliding in great circles, and hardly flapping its wings at all, then it is soaring.
If, on the other hand, it is flying straight and fast, and flapping its wings constantly to maintain speed, then the raptor is engaged in direct flight.
Most raptors use both flight styles but some, like the California Condor soar much more often than the others, like Sharp-shinned Hawk, which typically only soar during their migration.
What is meant when referring to a dihedral flight pattern?
When a bird holds its wings at an angle to the body, creating a dihedral or V-shape.
Photo by Mike Baird
For example, Northern Harrier and Turkey Vulture soar with their wings in a V-shape or what is referred to as a “dihedral” shape above their bodies.
Bald Eagle and Black Vulture, on the other hand, align their wings with their bodies, creating a much more flattened profile.
What FIVE foraging methods do raptors use (and can be useful for ID)?
- Hover & drop
- Perch & survey
- Ambush & chase
- Soar & swoop
- Low ambush
Hovering is an adaptation by raptors who dwell in grassland habitats where there aren’t many tall perches.
Perching is also done by birds of the open country where telephone poles offer the perfect vantage point to perch and survey.
Ambushing & chasing is great for forest-dwelling raptors who rely on concealment and camoflage to opportunistically pounce on birds, oftentimes with a fierce chase involved.
Soaring & swooping is the foraging method of choice for hunters who like a high vantage point. They then swoop down to pounce on unsuspecting prey or scavenge on a fallen creature.
Low ambush involves flying low and slow over grassland and marsh habitats, searching for prey, and then pouncing on them unseen.
Which FOUR raptors hunt by hovering and then swooping to catch their prey?
- American Kestrel
- White-tailed Kite
- Osprey
- Rough-legged Hawk
When conditions are windy, Red-tailed Hawk will also hover, although it is more like they are surfing the wind than actually hovering the way the afore-mentioned raptors do.
Which FIVE species of raptors like to perch on telephone poles and hunt for prey?
- Red-tailed Hawk
- Rough-legged Hawk
- Harris’s Hawk
- Swainson’s Hawk
- American Kestrel
All of these raptors are birds of the open country, from grasslands to desert.
Which FOUR species of raptors typically ambush and then chase their prey?
The forest-dwelling hawks:
1. Cooper’s Hawk
2. Sharp-shinned Hawk
3. Broad-winged Hawk
4. Northern Goshawk
These raptors will ambush their prey—usually smaller birds—and then chase after them. Their relatively short, broad wings allow them to fly through thick woods, while their long tails act as powerful rudders for quick, sharp maneuverability.
Which FOUR species of raptors dash after prey, relying on sheer speed to hunt?
- Merlin
- Gyrfalcon
- Peregrine Falcon
- Prairie Falcon
What SIX species of raptors like to hunt by soaring and then swooping down on prey?
- Golden Eagle
- Zone-tailed Hawk
- Short-tailed Hawk
- Turkey Vulture
- Black Vulture
- Mississippi Kite
Black and Turkey Vultures soar at height to look for fallen animals (or other vultures). They then swoop down to feast on the carrion. They don’t catch live prey.
What THREE species of raptors forage by flying low and slow over habitats like grasslands and marshes?
- Northern Harrier
- Snail Kite
- Rough-legged Hawk
Rough-legged Hawk also hover over the habitat and perch on telephone poles. So while some raptors tend to specialize in a certain foraging techniques (and are built accordingly), they can use multiple methods to acquire prey.
Why is sociability or gregariousness a useful clue for raptor ID?
Very few species of raptors hang out in large groups of other raptors!
Knowing which species of raptors are gregarious can help you determine what you’re looking at pretty quickly.
Most raptors are solitary or will pair up to nest. What are THREE exceptions to this rule?
- Vultures scavenge and roost communally.
- When there is an abundant food source, different species of raptors might congregate.
- Some raptors migrate in enormous mixed flocks.
What is meant by the term “kettle”, usually used during raptor migration?
A kettle is a large group of raptors—often several different species—that are soaring, wheeling, and circling in the air.
An example of this “kettling” behaviour is exhibited by raptors like Swainson’s Hawk, Broad-winged Hawk, and Swallow-tailed Kites, which soar in groups of dozens, if not hundreds of individuals during migration.
Most raptors, however, do not do this.
What do we mean when we talk about bobs and twitches in reference to bird behavior?
Unique, ideosyncratic movements that are particular to a species.
For example, American Kestrels bob their tails when perched on a wire. There doesn’t seem to be any apparent reason for it; it’s just a unique behavior to this bird and one that can help you tell it apart from the similar-looking Merlin.
What is the largest flying bird in North America?
California Condor
They have impressive wingspans of up to 3 m (almost 10 ft) and weight in at an average of 9 kg (20 lbs). They are estimated to live over 60 years.
