Lesson 3: 'Peep' Sandpipers Flashcards
The "peeps" are the small, stocky sandpipers of North America's mudflats, sandy shores, and rocky coastlines. The tend to be the most frustrating of all the shorebirds to identify because of their similar size, shape, and plumage across many different species, but this deck contains the cheat codes to their ID!
What is meant by the term “peeps?”
It is the term given to the group of small, stocky sandpipers.
They are called “stints” elsewhere in the world.
Describe the overall physical characteristics of the peeps.
Peeps are:
1. Small, stocky sandpipers
2. Largish heads
3. Short necks and legs
4. Medium-length bills
The peeps are tricky to ID because they all tend to look alike and, with the exception of the Red Knot, are quite small: smaller than a Killdeer.
How many species of peeps are found in North America and what are they?
Eleven
- Red knot
- Rock Sandpiper
- Pectoral Sandpiper
- Dunlin
- Purple Sandpiper
- Sanderling
- White-rumped Sandpiper
- Baird’s Sandpiper
- Western Sandpiper
- Semipalmated Sandpiper
- Least Sandpiper
Listed in decreasing order of size
True or false?
Most peeps have moderately bold wing stripes.
True
Photo by Andy Reago & Chrissy McClarren
Sanderling have the boldest wing stripes of all the peeps and Dunlin (pictured above) the second. So if you see a large flock of peeps flying, see if there are variations in the boldness of their wing stripes. It’s possible that among the species present in the greatest number, there may be some surprises!
What are the THREE largest species of peeps in North America?
Try to list in decreasing order of size
- Red Knot
- Rock Sandpiper
- Pectoral Sandpiper
Of course “large” is relative! All of these shorebirds are actually quite small, with the exception of the Red Knot, which is about the same size as a Killdeer, making it North America’s largest peep. Rock and Pectoral Sandpiper are smaller than a Killdeer.
What are the THREE smallest species of peeps in North America?
Try to list in increasing order of size
- Least Sandpiper
- Semipalmated Sandpiper
- Western Sandpiper
The Least Sandpiper is not only North America’s smallest peep but—at the same size as a sparrow—it’s also the smallest shorebird in the world!
Red Knot
Breeding plumage
About the same size as a Killdeer, Red Knot are North America’s largest peep. In breeding plumage, they are very colorful for a shorebird, with their head, neck and breast becoming a bold, rusty red color.
An important clue to pay attention to is that Red Knot have a strict preference for intertidal marine habitats, like coastal inlets, estuaries, and bays.
What is the Red Knot’s most noticeable trait?
In breeding plumage, it’s very colorful for a shorebird, with a rusty red head, neck and breast.
In the non-breeding season, the Red Knot is the typical shorebird combination of dull gray above and white below.
What distinctive feature do juvenile Red Knots have?
One that sets them apart from all other shorebirds?
The feathers on their back have both a black and white (double) outline.
Photo by Andrey Gulivanov
Most juvenile shorebirds have white edging to their feathers, which gives them a “scaly” or “scalloped” appearance.
Young Red Knots, however, show both a white and black outline to these feathers, which is beautifully illustrated in this photo. This is a totally unique feature to Red Knots. For once, a juvenile shorebird that is easier to identify than its adult (non-breeding) counterpart!
What is the preferred habitat of the Red Knot?
Intertidal marine habitats, especially near coastal inlets, estuaries, and bays.
What birds are these?
Sanderling
Non-breeding plumage
With a worldwide distribution, Sanderling are one of the most widespread wintering shorebirds. Note their pure white undersides, mostly white faces and necks, and very black legs and bills.
In flight, look for a black leading edge to the wings, strong black-and-white wing stripe (the most distinctive of all the peeps), and the pale tail and rump with a dark stripe in the center (not visible here). Since peeps often take off in mixed flocks, this is one way you can tell Sanderling apart from the other birds in the flock.
What are THREE physical traits indicate that you are looking at a non-breeding Sanderling?
- Snow white belly, neck, and face
- Black shoulder patch
- Black legs and bill (not dark gray)
Sanderling look a lot like other peeps but, in their non-breeding plumage, they are the most black-and-white of all the sandpipers, which are more brown-gray and white.
What THREE distinctive features are shown by Sanderling in flight?
- Black leading edge to the wings
- Broad white-and-black wing stripe
- Dark centerline to the otherwise pale tail and rump.
Sanderling have the most dramatically contrasted, distinctive wing stripe of all the peeps.
What habitats do Sanderling prefer?
Sandy beaches, although they do show up at ponds and mudflats during migration.
Dunlin
Breeding plumage
Dunlin are medium-sized sandpipers—large for a peep—with a “hunched” appearance, long drooping bill, and blackish (not yellow) legs.
In breeding plumage, they develop chestnut on their back and cap, as well as an extensive black patch on their bellies.
Describe the overall appearance of a Dunlin.
Try to mention four notable features
Dunlin are:
1. Medium-sized sandpipers (large for a peep) with
2. A slightly “hunched” appearance,
3. Long drooping bill, and
4. Blackish (not yellow) legs.
How does a Dunlin’s plumage change between the breeding and non-breeding seasons?
In the non-breeding season, the Dunlin is one of the plainest peeps with a dull brownish back and white belly (the long, drooping bill is key for identification).
In the breeding season, it develops a rufous cap and back, and an extensive black belly patch.
What THREE key features can help you to identify a Dunlin in flight?
- Bold white wing stripe
- Dark line down the center of the otherwise white rump and tail
- Long drooping bill
Dunlin have the second most prominent wingstripe of the peeps, second only to Sanderling, which look much more black-and-white in flight.
They also tend to fly in huge flocks or murmurations along the shore, as you can see in this photo!
Least Sandpiper
Breeding plumage
This is the smallest shorebird in the world—about the size of a sparrow, which helps enormously in its ID when it is foraging side-by-side with other shorebirds.
Also note its yellow legs, thin, tapered bill, and brownish/reddish plumage with white “snipe” stripes down its back.
The yellow legs are a very helpful trait for ID. However, they are often covered in mud, which can make them look quite dark! This is something to pay attention to in the field because it happens quite frequently.
What are THREE distinguishing features of a Least Sandpiper?
- Tiny size
- Yellow legs
- Thin-tipped, slightly curved bill
Where are Least Sandpiper most often found foraging?
At the upper edge of mudflats or along the drier margins of inland ponds.
This is not a strict rule, of course, but where you might see Dunlin, for example, foraging in the water, Least Sandpiper tend to daintily pick their way along the higher and drier edges of the habitat.
What sized flocks do Least Sandpiper typically gather in?
Smaller flocks of dozens or hundreds.
Photo by Melissa McMasters
Least Sandpiper can also be found singly or in small groups of less than 10. Certainly, however, you won’t find them gathering in enormous ten-thousand-strong flocks like Western Sandpiper.
Red Knot
Non-breeding plumage
In winter, Red Knot look like most other shorebirds with their dull gray-brown upperparts and creamy white underparts. Look for their dull yellow legs and medium-sized, short, thick, and blunt bills.
Also, remember, they are the largest peeps (about the same size as a Killdeer), which will help you tell them apart from almost all the other peeps. But if you struggle to distinguish them from Dunlin, the legs and bill should rule out any confusion.
Describe the foraging behavior of the Red Knot.
They walk and peck at surface prey, or probe beneath the mud for small mollusks, which they swallow whole.
Red Knot are often found foraging and roosting in very large (mixed) flocks of other shorebirds, such as Ruddy Turnstones and Dunlin.
Sanderling
Breeding plumage
Sanderling are known for their strongly contrasting white-and-black plumage, so you would be forgiven for thinking you were looking at a totally different bird! What you are looking at is the same bird but in breeding plumage.
In summer, males develop a patchwork quilt of black, white, and rusty spots on their backs and heads. However, their bellies remain as pure white and unmarked as they are in winter plumage, which is helpful for ID.
How does the male Sanderling’s plumage change in the breeding season?
Males develop rufous backs, heads, and chests but retain their pure white undersides.
Describe the beach foraging behavior of Sanderling.
They scuttle in flocks along the tide line, probing the sand as a wave retreats, and then running away from the surf as it comes back up the beach.
It is rather comical to watch!
Dunlin
Non-breeding plumage
In the non-breeding season, the Dunlin is one of the plainest peeps with a dull brownish back and white belly (the long, drooping bill is key for identification).
In fact, the name “Dunlin” originates from the word “dun”, which means dull brown and the term dunling which means “little brown one.”
True or false?
In winter, Dunlin can be found along both the east and west coasts of North America and also venture far inland for foraging grounds.
False
While Dunlin winter along both the east and west coasts of North America, they rarely venture inland. They also tend to be the latest of the sandpipers migrating through in the fall.
Least Sandpiper
Non-breeding plumage
In winter, Least Sandpiper lose their lovely chestnut coloring—as do most of the peeps that exhibit color during the breeding season—BUT they keep their yellow legs and, of course, their overall size and shape remain the same
Remember, its diminuitive size is really the hallmark trait of this tiny shorebird. Also note its medium-sized, slightly downcurved bill.
Red Knot
Breeding plumage
The rich red plumage, medium-length stocky bills, intricately red-white-and-black speckled backs, and coastal marine habitat all tell us these are Red Knot.
What birds are these?
Sanderling
Non-breeding plumage
The dark shoulder patch is diagnostic of Sanderling. Also note their pure white bellies, necks, and faces and jet black legs and bills.
In fact, in their non-breeding plumage, Sanderling are the most black-and-white of all the sandpipers so look for that white face, pure white belly, dark shoulder patch, and jet black legs and bill.
Where can you find them? Sanderling love sandy beaches, where you will find them running along the tide line, foraging; although they can and do show up at ponds and mudflats during migration.
What birds are these?
Dunlin
Breeding plumage
In the breeding season, Dunlin develop a rufous cap and back, and an extensive black belly patch. Always remember to be on the lookout for that long, drooping black bill as it’s diagnostic of the species!
In flight, the Dunlin shows a bold white wing stripe (the second most prominent of the peeps), and a dark line down the center of the otherwise white rump and tail.
What bird is this?
Least Sandpiper
Breeding plumage
Least Sandpiper tend to favor the higher, drier margins of mudflats and inland ponds for foraging. They also congregate in smaller flocks of dozens or hundreds, rather than thousands, like the Western Sandpiper.
What birds are these?
Pectoral Sandpiper
This medium-sized sandpiper’s distinguishing feature is its dark, densely streaked breast, which ends abruptly in the white belly. Note the sharp border between the streaking and white in the photo.
Also visible in the photo are the white “snipe stripes” down the reddish-brown back—another key feature of this shorebird.
How can you tell the very similar-looking Least Sandpiper from a Pectoral Sandpiper?
Least Sandpiper have similar markings and yellowish legs.
Least Sandpiper are half the size of Pectoral Sandpiper!
Photo by Wildreturn
Least Sandpiper are the smallest species of shorebirds in North America, hence their name.
What bird is this?
Western Sandpiper
Breeding plumage
Note the chestnut on the back, cheek, and crown; the dark (not yellow) legs and the long, slightly drooped bill (like a Dunlin). Western Sandpiper are also very small—not much bigger than a Least Sandpiper.
And if you look very closely at its left foot, you will notice some webbing between the toes. Western Sandpiper is one of only two peep species (the other being the Semipalmated Sandpiper) that have this webbing so it can be a very helpful diagnostic clue, if you can see it!
Describe TWO features of a Western Sandpiper’s breeding plumage.
- Chestnut on the back, cheek, and crown
- Chest and sides are heavily marked with chevrons that extend down the flanks
Photo by Andy Morffew
Also, in general, they have dark legs and a long, slightly drooped bill (like a Dunlin).
What is a Western Sandpiper’s distinguishing physical trait?
Short webbing between the toes, which can be hard to see.
Photo by Alan Schmierer
With the exception of the Semipalmated Sandpiper, no other peep has this webbing so it can be a helpful clue… if you can manage to spot it!
Semipalmated Sandpiper
These are small peeps, barely larger than a Least Sandpiper, with a short, blunt-tipped bill. They can be very hard to tell apart from the other peeps so pay attention to bill length because it is noticably shorter than that of the similar-looking Western Sandpiper, Least Sandpiper, and Dunlin in non-breeding plumage.
They are also distinctly uncolorful, lacking the chestnut plumage of the other peeps in the breeding season.
White-rumped Sandpiper
Breeding plumage
White-rumped Sandpiper are small shorebirds—medium-sized for a peep—that are named after their distinguishing feature: their pure white rump! This is always visible in flight and sometimes at rest, such as when they fluff their wings.
Other useful clues for ID include:
* Long wings that project past the tail when folded,
* Dark legs (not yellow),
* Arrowhead streaks on flanks (unusual for a peep), and
* Orange-brown patch at the base of the bill’s mandible (visible in this photo)
What feature shown in flight (and when the wings are open) is a giveaway clue for identifying the White-rumped Sandpiper?
Its white rump!
Photo by Ryan Hodnett
In the above image, the sandpiper closest to us shows off its white rump while taking a bath.
Pectoral Sandpiper
The name “Pectoral” refers to the starkly contrasted heavily streaked breast above and the white belly below. This is a diagnostic feature of this species so if you spot it, try to verify the following additional clues and you can be confident you have a Pectoral Sandpiper:
- Yellowish legs
- Slightly drooping bill
- Size (close to a Killdeer)
The latter point is important because Pectoral Sandpiper tend to look similar to Least Sandpiper, except they are much bigger.
What bird is this?
Baird’s Sandpiper
Non-breeding plumage
The white edging to the darker back feathers gives this bird a scaly appearance. Usually, this scaliness or scalloping is a trait exhibited by juvenile shorebirds but in the case of the Baird’s Sandpipers, it’s one of their hallmark traits!
Like the White-rumped Sandpiper, they also have long wings that extend past the tail and are, overall, a very brown-and-white bird.
Western Sandpiper
Juvenile
Note the chestnut stripes on the back—juvenile Western Sandpiper have these chestnut “racing stripes”. Also note the long, slightly drooped bill and blackish legs, not yellow.
This species can often be confused with Least Sandpiper, which are similar in size but have yellow legs and a shorter, more tapered bill.
Semipalmated Sandpiper
Interestingly, the word ‘palmated’ means “webbing” and so this peep is named after the short webbing between its toes, which you can see quite nicely in this photo. There is only one other small sandpiper with this kind of webbing and it is the Western Sandpiper, which has a longer bill and more chestnut coloring on its back, face, and crown.
The Semipalmated Sandpiper has a (1) short, blunt bill, a (2) heavily-streaked crown, and (3) overall lack of color. In other words: they are very brown and white.
White-rumped Sandpiper
Breeding plumage
Note the orange-brown patch at the base of the bill’s mandible, the dark (not yellow) legs, and the long wings that project past the tail.
In the breeding season, these peeps have a warm brown back, crown, and face patch that creates a faint white eyebrow stripe. They also have a heavily streaked breast that does not end as abruptly in a pure white belly as it does with Pectoral Sandpiper.
Baird’s Sandpiper
Juvenile
Note the scaly back, buffy chest band and unmarked creamy white belly and flanks. Other peeps might have streaks or chevrons on their bellies and flanks but the Baird’s Sandpiper’s are distinctly unmarked.
Also note the long wings that extend beyond the tail and overall brown-and-white plumage with a distinct lack of color.
Finally, the Baird’s Sandpiper shows exclusively gray-brown plumage and never rufous, as is the case with many other peeps in the breeding season.
Western Sandpiper
Breeding plumage
Note the chestnut on the back, cheek, and crown, as well as the chest, sides, and flanks that are marked with chevrons.
In spring, this species migrates in the millions up the Pacific coast towards their breeding grounds in the Arctic. They spend winter on both the eastern and western coastline of North America, but are more commonly found in the west, hence their name.
Pectoral Sandpiper
Note the streaked breast strongly contrasted with the white belly, yellowish legs, slightly drooping bill, and white “suspender” stripes down the back.
An important habitat-related clue for the Pectoral Sandpiper is that they seem much more at home on the grass than in the water and mud. (Of course this picture shows that they do not strictly avoid water either!)
So while other sandpipers may be scuttling about and probing the water and mud, Pectoral Sandpiper will often be found on the strips of grassy land between the muddy pools.
White-rumped Sandpiper
Breeding plumage
One of the White-rumped Sandpiper’s key identifiers is its foraging behavior. When it lowers its head to probe in the mud or beneath the water, it tilts its entire body downwards as we can see in this photo. As it repeatedly lowers and raises its head to forage, the bird’s body performs a sort of see-saw motion!
All the other peeps maintain a flat back perpendicular to the ground when foraging. This alone can help you make your ID, provided you sniff out a few other clues, like the brown patch at the base of the bill and the white rump.
Semipalmated Sandpiper
Short, blunt bill, heavily-streaked crown, slight webbing between the toes (if you look really closely), and lack of any strong chestnut coloring tell us this is a Semipalmated Sandpiper!
Baird’s Sandpiper
The (1) dark back feathers with pale edges creating that “scaly” appearance, (2) buffy chest band, (3) clean, creamy white belly and flanks, (4) long wings that extend beyond the tail, and (5) overall gray-brown-and-white plumage tell us this is a Baird’s Sandpiper!
Another thing to remember is where you see this bird in its habitat. Similar to Pectoral Sandpiper, Baird’s Sandpiper typically prefer the higher, grassier portions of the mudflats than the other peeps.
Rock Sandpiper
Breeding plumage
Rock Sandpiper are plump, medium-sized shorebirds that lie towards the larger end of the peep spectrum.
During the breeding season, they develop chestnut plumage on the back, a rust-colored crown, dark ear patch, and diffuse black belly patch. With their slightly droopy bill, you would be forgiven for confusing this bird with a breeding Dunlin but there are a few differences to pay attention to.
The Dunlin has:
1. A more solid black belly patch, which is located lower down on the belly.
2. A longer, droopier bill.
3. Black legs (the Rock Sandpiper’s are orange although in this picture they look quite dark. This is why it’s so important to take into account multiple clues!)
Rock Sandpiper
Non-breeding plumage
This bird looks completely different from its breeding self, which more closely resembles a Dunlin in breeding plumage.
Fortunately, you are most likely to see Rock Sandpiper in their non-breeding plumage, which is quite a bit easier to distinguish from a Dunlin. (This is because they migrate to the high Arctic in the summer.)
Otherwise, the features to pay attention to include the yellowish legs, orange bill base, overall plump shape and size, and preferred habitat: coastal marine, usually in the splashing surf.
Purple Sandpiper
Transitional plumage
If the range of the Purple Sandpiper overlapped with that of the Rock Sandpiper, birders everywhere would have a real challenge on their hands because these two species look REALLY similar in non-breeding plumage.
They are both plump, medium-sized shorebirds that love rocky, coastal marine habitats in the splash zone. The Purple Sandpiper is mostly dark gray with spotted underparts and in certain light, their back has a purplish sheen, which is where they get their name from.
Their legs and bill base are a bright yellow-to-orange in color.
Rock Sandpiper
Non-breeding plumage
Note the dark droopy bill with yellowish base, dull brown-gray upperparts and creamy, speckled underparts, and yellowish legs. Also consider the habitat (literally rocks) and range, which, in the case of the Rock Sandpiper, is the Pacific coast.
Purple Sandpiper
Non-breeding plumage
Purple Sandpiper are found exclusively along the Atlantic Coast (they have an eastern-restricted range), where they spend winter, congregating in small flocks.
Purple Sandpiper
Non-breeding plumage
Can you see the purplish sheen on the back? It is almost like the gray on the back is tending towards mauve. This is the feature from which the Purple Sandpiper gets its name!
Also note the habitat: the mussel and seaweed covered rock and the splashing surf. This is the ideal habitat for this surf-loving peep!
What key physical trait can help you tell a Surfbird apart from a Rock Sandpiper, both in non-breeding plumage?
Especially since they love the same habitats and are often found hanging out in mixed flocks.
The Surfbird has a much shorter, stouter bill.
Whereas Rock Sandpiper have longer, slightly drooped bills. They are also much smaller than Surfbird!
