Lesson 1: Shorebird Essentials Flashcards
From shape, size, and foraging behavior to habitat, range, and plumage: receive a grand overview of the various identification hacks and tools you need to take on all of North America's 47 shorebird species. This deck is preparation for the group-specific decks to come.
What are the FOUR families of shorebirds?
According to the scientific nomenclature
- Plovers
- Oystercatchers
- Avocets & stilts
- Sandpipers & relatives (by far, the largest group)
Illustrations here and throughout this deck offer a very rough approximation of relative size.
What are the EIGHT subgroups of shorebirds in North America?
- Tringas
- Peeps
- Snipe-types
- Phalaropes
- Plovers
- Curlews & godwits
- “Grass pipers” & turnstones
- Oystercatchers, avocets & stilts
The Cornell Lab of Ornithology has informally divided all of the shorebirds of North America into EIGHT subgroups based on shape. This is done purely for the purpose of making identification easier.
Why is it important to learn the key characteristics of the 8 shorebird subgroups?
Learning to recognize which subgroup a shorebird belongs to narrows your options down considerably, making your job of identifying much less overwhelming!
What useful strategy can you use to identify shorebirds in environments where there are large mixed flocks of them foraging together?
Photo by Ingrid Taylar
Focus on a single bird, identify it, and then move on to the next one (and then the next one…).
Shorebirds can be tricky to identify because their plumages tend to look so similar across many different species. But if you move through a flock bird-by-bird (noting each one’s key features and foraging behavior, etc), you will actually start finding shorebird ID fun, not overwhelming!
How can having two or more species of shorebirds in a single location be useful for identification?
Side-by-side tell, you can appreciate their relative size and shape.
Photo by Wildreturn
Other shorebirds can serve as useful yardsticks against which to measure relative size, shape, and other physical traits, like the length and shape of the bill or the length and color of the legs.
For example, being able to say if something’s bigger, smaller, or the same size as a Killdeer, Western Sandpiper, or American Oystercatcher, can go as far as clinching an ID. With practice, you will develop an instinct for what is small, medium-sized, and large (and the shades in-between).
How can you gauge the approximate size of a shorebird?
Use other shorebirds in the field (or from memory) as a reference
Example: Lesser and Greater Yellowlegs are pretty hard to tell apart until you learn that Lesser Yellowlegs are about the same size as a Killdeer, while Greater Yellowlegs are much bigger.
You could also compare their size to a bird that you do know well, such as a sparrow, robin, or crow!
What are the THREE most important clues for shorebird ID?
Shape, behavior, and size
Shape narrows the bird down into one of the eight subgroups: (1) tringas, (2) peeps, (3) phalaropes, (4) snipe-types, (5) plovers, (6) curlews & godwits, (7) “grass pipers” & turnstones, and (8) oystercatchers, avocets & stilts.
Behavior, particularly foraging behavior is distinctive in many shorebird species and can further narrow your search down to a few individual species.
Size is a third clue that separates remarkably similar-looking species from each other: species that may also overlap in range and habitat.
Aside from shape, behavior, and size, what are FOUR other clues you can use to identify shorebirds?
- Color patterns & markings
- Habitat
- Range
- Calls
- Color patterns & markings like wing stripes, rump color, eye rings, eye-stripes, and chest barring.
- Habitat like ocean beaches, pond edges, mudflats, and grasslands, etc.
- Range: Is the shorebird in question within its typical range, taking into account migration? Or is it even the right season for that shorebird to be there?
- Calls: Useful for a handful of species that have quite distinctive calls.
How many clues should I look for to make a confident shorebird ID?
Three or more
Shorebirds tend to have quite similar markings across many different species or are even completely unremarkable and dull in the non-breeding season, making plumage an unreliable tool for identification.
Look for a variety of clues—three or more—especially size, shape, habitat, calls, behavior, and range. If three clues point strongly to a certain species and exclude all others, you should feel confident in your ID!
What are the main physical traits of the Tringa-type shorebirds?
- Tall, thin, and lanky sandpipers
- Overall size is medium to large
- Long, straight bills
- Medium-to-long neck with a relatively small head
© Glen Bodie
Examples include: Lesser and Greater Yellowlegs, Solitary Sandpiper, Stilt Sandpiper, and Willet.
What are the main physical traits of the peeps?
AKA stints
- Small-to-medium sized sandpipers with short legs
- Overall stocky appearance
- Short necks, largish heads
- Medium-length bills
Examples include: Western Sandpiper, Least Sandpiper, Dunlin, Sanderling, and Baird’s Sandpiper.
What are the main physical traits of the “snipe-type” shorebirds?
- Short, chunky shorebirds
- Very long bill, which they use to probe the mud for food
- Relatively short neck
- Moderately short legs
© Brian Avent
Examples include: Short- and Long-billed Dowitchers, Wilson’s Snipe, and American Woodcock.
What are the main physical traits of the phalaropes?
- Similar in shape to the Tringa-type shorebirds
- Razor-thin bills (exception: Red Phalarope)
- Distinctive behavior: they swim like ducks
Photo by Gregory Smith
Examples include Wilson’s Phalarope, Red Phalarope, and Red-necked Phalarope.
Unlike any other shorebird, phalaropes are often seen foraging far out from the shore, paddling around the middle of lakes in summer, like ducks!
What are the main physical traits of the plovers?
They have:
* Large heads, short necks and fat bodies
* Short stout bills
* Medium-to-short legs for a shorebird
* Plumage often shows black patterning
Photo by Gregory Smith
Examples include: Killdeer, Black-bellied Plover, American Golden-plover, Piping Plover, and Snowy Plover.
Note: many shorebirds—particularly the large plovers, like American Golden-Plover—vary tremendously in plumage between the breeding and non-breeding seasons, which is why recognizing their relative shape and size is crucial for ID.
What are the main physical traits of the curlews & godwits?
- The largest of the shorebirds
- Big and bizarre with really large/long bills
- Godwits’ bills curve up and curlews’ bills curve down
© Brian Avent
Examples include: Long-billed Curlew, Whimbrel, Marbled Godwit, and Hudsonian Godwit.
What FIVE species make up the subgroup of “grass pipers” & Turnstones?
“Grass pipers”
* Uplands Sandpiper
* Buff-breasted Sandpiper
Turnstones
* Ruddy Turnstone
* Black Turnstone
Surfbird
The “grass pipers” are habitat specialists that like short, grassy habitats more than the usual shorebird hotspots (mudflats and sandy beaches).
Turnstones are like plovers—round and stocky with short-to-medium bills—but they are found almost exclusively in marine habitats where the ocean waves crash upon the rocks/shore.
We have also included the Surfbird in this category because it is similarly sized and shaped to the turnstones, and is commonly found in the same habitat; however, it actually belongs to the genus Calidris—the same as the peeps!
What FOUR species make up the subgroup of Oystercatchers, Avocets & Stilts?
- Black Oystercatcher
- American Oystercatcher
- American Avocet
- Black-necked Stilt
These large, easily-identifiable, bold black-and-white shorebirds do not really belong in any other category, so we slap them together in this mixed bag.
Can you name the anatomical features on this Spotted Sandpiper?
Image credit: Becky Matsubara
Can you name the anatomical features on this Dunlin?
Image credit: Andy Reago & Chrissy McClarren
Why is shape such a helpful ID tool for shorebirds?
The traditional clues provided by plumage color and markings do not help much with shorebird ID because plumages:
1. Vary very little between many species
2. Vary naturally from individual to individual
3. Change wildly from season to season
4. Are, at times, completely featureless
When it comes to shorebird ID, shape tells us so much more than plumage. It allows us to narrow a shorebird down to one of the eight subgroups and possibly even down to a handful or birds or even an individual species.
What FIVE aspects of a shorebird’s shape should you look out for?
- Bill length and bill shape
- Neck length
- Body shape (skinny or plump)
- Leg length (and color)
- Silhouette in flight
The lattermost aspect takes into account bill length and shape, and leg length (viewed by how much past the tail the legs project). In some cases, flight silhouette can be very distinctive, as is the case with:
- Upland Sandpiper, which has a very long tail (for a shorebird)
- Black-necked Stilt, whose long legs project almost comically past its tail
- Long-billed Curlew, whose incredibly long and curved bill is impossible to miss
- Hudsonian Godwit, which has very long, thin, pointed wings
What are the FOUR shorebird bill shapes to look out for?
- Curved upwards
- Straight
- Curved downwards
- Drooped
Examples:
1. Curved upwards: American Avocet, Marbled Godwit, and, very subtly, Greater Yellowlegs.
2. Straight: Most sandpipers, Wilson’s Snipe, and Short- and Long-billed Dowitchers
3. Curved downwards: Long-billed Curlew and Whimbrel
4. Drooped: (the tip of the bill droops downwards) Stilt Sandpiper and Dunlin
Which shorebird subgroup(s) have very short bills?
Plovers
Which shorebird subgroup(s) have very long bills?
Snipe-types, curlews and godwits
What shorebird subgroup(s) have short necks?
Peeps, plovers, and snipe-types
What shorebird subgroup(s) typically have long necks?
Tringas, curlews, and godwits
When you see a shorebird in flight, what THREE traits related to its shape should you look for to get valuable ID clues?
- Bill length: is it short, medium, or long?
- Bill shape: is it curved upwards, downwards, or straight?
- Leg length: do they project past the tail? How far? Or not at all?
Photo by Ron Knight
This photo illustrates the unique flying profile of shorebirds like the Whimbrel, whose long, curved bill is quite hard to miss!
What NON-SHAPE related clues should you look for in flying shorebirds?
Aside from leg length and bill length and shape
- Overall size: how big are they?
- Wing stripes: bold or absent?
- Rump color: white, black, rufous, or patterned?
- Leg color: red, yellow, or dark?
- Flight style: any behavioral clues?
- Call: many shorebirds become vociferous during flight!
Once you have collected your visual clues, you can then consider factors like range and habitat. Is it the right time of year for the species you are considering? The right habitat? And so on.
In what THREE ways can a shorebird’s behavior provide valuable clues?
- Flight style
- Bobs and twitches
- Foraging method
For example:
* When flushed, Wilson’s Snipe typically take off in a zig-zag flight style.
* Spotted Sandpiper constantly bob their tails, while Solitary Sandpiper constantly bob their heads (like they have the hiccups).
* When foraging, American Avocet slice their bills through the water in a scything motion, while dowitchers constantly probe the mud in an up-down motion that resembles a sewing machine.
Describe a typical shorebird’s flight style
Very fast, direct flight with rapid wingbeats
Why is it important to pay attention to shorebirds’ foraging behavior?
You can easily identify a shorebird’s subgroup and, in some cases, narrow the possibilities down to a few species based on foraging behavior alone.
Foraging behavior is probably the most important behavioral marker of shorebirds. It can even help to identify a species or, at the bare minimum, the subgroup it belongs to without taking into account any other clues!
Describe the typical foraging behavior of the plover subgroup
Plovers run, peck, and stand still (repeat)
These shorebirds scuttle along the beach, pick at the ground, stop (stand still), look for the next morsel, and then scuttle after it; repeating that over and over again.
Describe the typical foraging behavior of the peeps subgroup
Peeps keep their heads down and constantly probe the mud as they walk
Photo by Wolfgang Sauber
The exceptions to this rule are useful ID hacks, for example:
1. White-rumped Sandpipers stick their tails up in the air as they forage.
2. Sanderling (beach birds) constantly scuttle up and down the beach, avoiding the waves as they crash on the shore.
Describe the typical foraging behavior of a Yellowlegs
Both Greater and Lesser
Stroll n’ pick
© Brian Avent
Yellowlegs typically move constantly but slowly, keeping their heads up, picking at the occasional morsel at, or just under the surface of the water.
Greater Yellowlegs will also “scythe” the water, slicing their bills from side-to-side under the water, a technique that is unique to this shorebird and one other, the American Avocet.
Describe the typical foraging behavior of the Phalarope subgroup
Totally unique for a shorebird: they swim like ducks!
© Brian Avent
Phalaropes are often found paddling like ducks over the deepest parts of ponds and lakes, and spend winter out on the open ocean.
Additionally, when they forage, they spin in tight circles, whipping up edible morsels from lower down in the water column, bringing them to the surface for the bird to eat.
Where do many North American shorebird species go in the summer?
They migrate to the Arctic to breed
Where do many North American shorebirds go in the winter?
They migrate southwards to the very southern United States and southwards through Central and South America.
What time of year is the U.S. and Canada most likely to see migrating shorebirds?
Late March through May and again from July to mid-October.
True or false
All species of North American shorebirds breed in the Arctic in summer and migrate south for the winter.
False
While many North American shorebirds follow this annual migration, there are lots of exceptions. Some do not migrate at all, while others breed inland and winter along the shore within the confines of the North American continent.
How can the timing of migrations of specific shorebirds be a useful ID tool?
It tells you which shorebirds are likely around at that time of year
For instance, Short-billed Dowitcher end their fall migration towards the end of September / early October, while the Long-billed Dowitcher end theirs later. So if you come across a shorebird in November or December that you can tell is a Dowitcher, you can be pretty sure that it is a Long-billed Dowitcher.
What are the SEVEN shorebirds with western-restricted ranges in North America?
- Pacific Golden-Plover
- Mountain Plover
- Black Oystercatcher
- Black Turnstone
- Wandering Tattler
- Rock Sandpiper
- Surfbird
These birds are rarely seen east of the Mississippi River
What are the THREE shorebirds with eastern-restricted ranges in North America?
- Wilson’s Plover
- American Oystercatcher
- Purple Sandpiper
These birds are rarely found away from the Atlantic and Gulf coasts.
What TWO shorebird groups can those that do not have a western or eastern-restricted range be divided into?
Those that are found:
1. All across North America, e.g. Greater Yellowlegs
2. In the Eastern and Central U.S. and Canada, e.g. Baird’s Sandpiper
There are 11 species in the latter group. Some of them occasionally make it west of the Rocky Mountains but, in general, they are much more common to the east of this barrier.
Which is the only shorebird species that does not migrate?
American Woodcock
Photo by Fyn Kynd
These birds stick to their preferred habitat of forests and scrubby areas (not wetlands) in the eastern half of the United States and Canada.
What TWO habitats are amenable to most shorebird species?
Mudflats (marine and riverine) and sandy beaches
Name THREE shorebirds that specialize in grassland and field habitats
- Upland Sandpiper
- Buff-breasted Sandpiper
- Mountain Plover
American Plover, Pacific Golden-Plover, and Killdeer can also be found in these habitats but do not specialize in grasslands and fields. I.e. they are found in wetland habitats, too.
What THREE Atlantic Coast shorebirds specialize in rocky intertidal zones, where the waves constantly smash upon the rocks?
- Ruddy Turnstone
- Purple Sandpiper
- American Oystercatcher
What FIVE Pacific Coast shorebirds specialize in rocky intertidal zones, where the waves constantly smash upon the rocks?
- Black Turnstone
- Wandering Tattler
- Rock Sandpiper
- Black Oystercatcher
- Surfbird
Once you have learned the main habitats certain shorebirds like to forage in, what secondary—though no less important—habitat clue should you look for?
Exactly where in the habitat a bird is foraging
or spending most of its time
This is the same concept you apply when considering where in the forest a bird is spending most of its time.
For example Hermit Thrush prefer the forest floor; Wilson’s Warbler like the lower parts of the understory; and American Redstart are most often seen flitting about the canopy. Knowing this about these birds will help you find them and provide valuable clues to then identify them.
Let’s say that you are birding around a largish body of water, like a lake or estuary. Name FIVE typical habitat zones where different shorebirds might be found.
Give some examples of shorebird species found in each
Photo by James Allan
- In the grassy areas away from the water (Killdeer, Baird’s Sandpiper, and Buff-breasted Sandpiper)
- On the muddy flats around the water’s edge (peeps and plovers)
- In the shallow water (Stilt Sandpiper, Lesser Yellowlegs, and Dowitchers)
- In the deeper water (large, long-billed, long-legged shorebirds like Greater Yellowlegs, Hudsonian Godwit, and Avocets).
- Out on the open water (Phalaropes)
What FOUR color markings on the face can provide help with shorebird ID?
- Eye rings
- Eye stripes
- Eyebrow stripes (supercilium)
- Crown stripes
Crown stripes are stripes of darker plumage over the top (or crown) of the head.
Eyebrow stripes are stripes of darker or paler plumage located right above the eye.
Eye stripes are stripes of darker or paler plumage that run through the eye line.
Eye rings are patches of, usually, white skin or paler plumage around the eye. They can be bold and unbroken (Solitary Sandpiper) or thin and broken (Spotted Sandpiper).
What four DARK markings exhibited by some shorebirds are useful clues for ID?
Remember, plumage isn’t often a reliable clue in shorebird identification but there are some markings and colors that will definitely direct you towards the correct ID, especially when considered in tandem with behavior, shape, habitat, and range.
- Black auxiliaries or armpits (e.g. Black-bellied Plover)
- Chest bands (e.g. Killdeer)
- Black rumps (e.g. American Golden-Plover in breeding plumage)
- Black belly patches (e.g. Dunlin in breeding plumage)
B = Breeding
NB = Non-breeding
Another dark marking that’s helpful for ID—and unique to Sanderling—is a black leading edge to the wing.
What five LIGHT markings on a shorebird’s body are useful clues for ID?
Remember, plumage isn’t often a reliable clue in shorebird identification but there are some markings and colors that will definitely direct you towards the correct ID, especially when considered in tandem with behavior, shape, habitat, and range.
- Snipe stripes on the back (e.g. Wilson’s Snipe)
- White wedge up the back (e.g. Dowitchers)
- Wing stripes (e.g. Dunlin)
- White feather tips giving the back a “scaley” appearance (e.g. Baird’s Sandpiper)
- White rump (e.g. breeding Black-bellied Plover)
B = Breeding
For which shorebird subgroup does rump color play a particularly useful role in identification?
Plovers
- Black-bellied Plover have white rumps
- American and Pacific Golden-Plover have dark rumps
- Killdeer have rust-colored rumps (distinctive)
The reason it is so helpful to know this is for identifying plovers in flight. Black-bellied Plover can be very difficult to tell apart from the Golden-plovers but with its bright white rump (and not dark rump) visible in flight, you can make a quick and confident ID!
What are the only North American shorebirds that display a white wedge during flight?
A v-shaped patch of white that extends from the rump up between the shoulder blades.
- Long-billed Dowitchers
- Short-billed Dowitchers
- Black-necked Stilt
© Brian Avent
This photo of Long-billed Dowitcher beautifully illustrates how the white wedge becomes visible in flight.
Which shorebirds have a black belly?
In breeding plumage
The three large, unbanded plovers and, of the peeps, only the Dunlin and Rock Sandpiper
B = Breeding
When are markings like spots, stripes, or streaks most often useful for shorebird ID?
When the bird is in breeding plumage
Although many shorebirds have markings, they are not always useful for ID because many different species can look so incredibly similar, especially in non-breeding plumage. That said, there are a few times when markings—or even a lack of markings—can help distinguish one shorebird from another.
