Solitary and Spotted Sandpipers

At the mention of sandpipers, many birders mentally groan.  After all, sandpipers are those dull, brownish little creatures that skitter over mud and all look alike.  In other words, it can be really hard to appreciate them.  But actually, on closer study, sandpipers are unusual and highly fascinating birds.  And, no, they don’t all look alike!  I will focus on two very distinctive, common sandpipers that can be seen in migration now: the Solitary Sandpiper and the Spotted Sandpiper.

Although they are not closely related, the Solitary Sandpiper (Tringa solitaria) and the Spotted Sandpiper (Actitis macularius) are often seen together feeding in the same ponds and lakes, frequently those with woods or at least low-lying vegetation nearby.  Both can be found migrating in Mississippi from about March to June in the spring, and late July to late October in the fall.  The Spotted Sandpiper is an occasional winter resident in the state, as well, but is more common along the coast than inland.

Both sandpipers forage and migrate singly or in small groups, and both exhibit tail-bobbing behavior.  With the Spotted, the entire body is teetered; the bird is in constant, jittery motion: scampering along the water’s edge, picking up small insects, mollusks, crustaceans, and even tiny fish.  The Solitary Sandpiper has slower, more deliberate movements, and when it pauses, it often bobs its head and tail.  It has longer legs and a longer bill than the Spotted, which enables it to feed in slightly deeper water, where I assume the menu would include bigger fish and frogs!  As an additional feeding adaptation, it often shakes its foot above the water to draw small fish and insects to the surface.

If you come unexpectedly upon either of these sandpipers, they will probably fly up immediately, uttering high-pitched peet-WEET calls (the Solitary’s call is the higher pitched of the two).  Fortunately, their flight styles are very different and distinctive.  The Solitary Sandpiper has graceful, swallow-like wingbeats and displays long, pointed wings and white edges on its tail.  Spotted Sandpipers fly close to the water and give fluttery, shallow beats of their shorter, more-rounded wings, each of which shows a thin, white stripe.

Once the sandpipers land on the bank and begin feeding again, their colors and patterning are apparent.  The Solitary Sandpiper is slightly larger than the Spotted, with a longer neck and body, and it has a wide, white eye-ring that gives it an alert look.  Its head, neck, and breast are finely streaked with brown, its belly is white, and its back is dark brown and shiny, with a dusting of tiny white spots.  The thin, dark bill and dark, greenish-gray legs complete the picture.  The Spotted Sandpiper is relatively small and stocky, with orange legs and bill, brown upperparts, a white eyebrow and slight eye-ring, and in the breeding season a boldly spotted breast and belly.  At least before the birds molt in the fall and replace the spotted front with plain white, you can sometimes tell the sexes apart.  Females have larger spots that extend farther onto the belly than males.

But why would the female bird be more distinctively marked?  The answer lies in the Spotted Sandpiper’s breeding biology.  Along with phalaropes, it is unusual in that the females are polyandrous, mating with more than one male—sometimes up to five!  Each time after mating, the female lays a clutch of up to four brownish eggs, which the male is solely responsible for incubating.  However, the female does help with constructing the nest—a shallow scrape in the ground, lined with grass.  After the eggs hatch, the male alone raises the chicks, which are born precocial like all sandpipers.

While the Solitary Sandpiper is monogamous and doesn’t exhibit such unusual breeding behavior as the Spotted, it is unique among North American shorebirds in that it nests in trees.  A female Solitary Sandpiper will add a little extra nesting material to the abandoned nest of a songbird, such as a Rusty Blackbird, American Robin, or Cedar Waxwing, incubate her four well-camouflaged, brownish eggs, and care for the young with her mate.  Tree-nesting is so unusual among shorebirds (the Green Sandpiper of Eurasia is the only other species known to do it regularly) that, for decades, no one was sure where the Solitary Sandpiper nested until 1903, when the secret was finally discovered.

Spotted Sandpipers are one of the most widespread shorebirds, commonly found over much of North America, although they aren’t known to breed in Mississippi and some other southern states.  Solitary Sandpipers are more restricted in range, occurring in the breeding season mainly in Canada and Alaska.

The numbers of both of these sandpipers appear to be fairly stable, and that’s good news.  With care and protection, generations years into the future will be able to observe the fascinating behaviors of these and other birds that have been living here for eons.  A world without the little brown sandpipers that enliven our fields, woods, and wetlands would be bleak.

Too Much of a Not-So-Good Thing

On a sunny afternoon in February, my sister was about to let the dog outside when she noticed that there was a small bird squatting, dazed and sluggish, on the back patio.  She handled the bird with gloves, and, as is usual, I was called to investigate the situation.  It turned out that the bird was a Purple Finch—either an adult female or an immature, judging from its lack of “purple” (or, more accurately, pinkish) coloration.  Given the predatory propensities of dogs, and the fact that the finch did not seem to be in any condition to fly, it was probably fortunate that my sister had checked before simply allowing the dog to run outside.

The finch being handled

The seed feeder that I maintain for wild birds in the backyard is situated far enough from the house that I doubted that the finch had fled from it—because of a hawk, let’s say—and slammed into the windows.  Of course it was a possibility, but I thought that the likelier explanation was that the finch was intoxicated.  Drunkenness in birds occurs more often than some people might suspect.  In the winter and early spring months, warm days may cause fermentation in the sugary berries that grow on shrubs and vines.  If birds then consume these potent ethanol capsules in large enough quantities, they may exhibit symptoms of inebriation: flying erratically or weakly, dropping to the ground, lurching lethargically, etc.  In rare cases, birds may die from alcohol poisoning.  

While I didn’t entertain any real fears that the finch would die, I was pretty convinced that it was suffering from a mild case of intoxication, probably from eating too many overripe privet berries.  Over the previous few weeks, I had regularly observed the wintering flock of Purple Finches munching on these blue fruits, usually in the company of Cedar Waxwings—which, incidentally, seem to be found in a drunken state more often than most North American birds, if online reports and articles are any indication.  It’s also possible, although less likely, I think, that the toxin syringin, found in privet, had poisoned this bird.

Purple Finch feeding on privet berries

More finches at the feast

Since it wasn't practical for us to simply leave the finch on the patio, my sister and I decided to set it on a large stump near the feeder and wait for it to recover.  The feeder itself hangs under some very large oak trees and near an expanse of fairly dense shrubbery—plenty of cover to make the bird feel more secure.  We went about our business for a while, and, apparently, the bird eventually sobered up.  Several of its Purple Finch flockmates were also hanging around the backyard feeder, so, after a while, I completely lost track of which bird had been ailing.  They all seemed alert and healthy.  Success!

Recovering

On a not-unrelated note, in Googling a few things for this blog post, I found yet another item to add to my growing list of concerns about Chinese privet, the shrub on which the Purple Finches had been feeding.  Perhaps unsurprisingly, there has been research indicating that fruit from invasive plants may not be healthy for birds.  Specifically, many species invasive to North America contain more carbohydrates than their native counterparts, which tend to contain more fats.  Unfortunately, this means that birds often go for the “quick energy,” so to speak, even if it hurts them farther down the line.  Another problem that I hadn’t considered before is that feeding on invasive plants might interfere with mate selection in some species of birds.  For example, male Northern Cardinals that feed heavily on the nonnative Amur honeysuckle will have more vibrant plumage and may therefore be more attractive to female cardinals than males that feed on native plants, simply because the honeysuckle contains extremely high levels of carotenoids—i.e., pigments found in plants and certain other groups of organisms.  Male cardinals that don’t feed on Amur honeysuckle may well be healthier than their counterparts, but their plumage won’t reflect that.  Finally, I have to wonder if the higher levels of carbohydrates in many invasive species increase the likelihood that their fruits will ferment and lead to inebriated birds.  

Yes, I realize that I’m probably a bit hypocritical on this subject: I keep a feeder in the backyard.  It encourages birds to be lazy and to congregate in an area that normally wouldn’t interest them.  On the other hand, I would guess that the seed mixes they eat from it are healthier than the berries from privet and Japanese honeysuckle, to name only a couple of common invasives in this region, and at least the feeder isn’t strangling trees and shading out native vegetation.  Chinese privet is a tough weed to eradicate.  The best that most of us amateur naturalists can do on an individual level to combat its effects is to plant native shrubs and cut or uproot the privet wherever possible.  And, of course, keep alert for birds that might have had a little too much of this not-so-good thing.

Links:

https://www.newhopeaudubon.org/blog/invasive-plants-are-not-for-the-birds/

https://news.nationalgeographic.com/news/2014/12/141203-drunk-birds-animals-science-winter-global-warming/

https://plants.ces.ncsu.edu/plants/all/ligustrum-japonicum-l-sinense-l-lucidum-l-v/

Birdsong

Singing Indigo Bunting

As any serious bird-watcher knows, the term that denotes our hobby is terribly misleading.  A newcomer or an outsider usually assumes that because the pursuit is called “bird-watching”, then they should always be able to see birds, and see them well.  Binoculars, naturally, are often thought of as instruments serving to endow bird-watchers with a nearly super-human ability to see the birds that fly their merry ways, unseen to the casual observer.

Nothing could be further from the truth.  The fact is, “bird-watching” could just as easily be called “bird-listening.”  According to bird-watching experts, most birders (a term I prefer to bird-watchers—but due more to its brevity than its accuracy) identify at least 80 percent of the birds they find by sound, not sight.  Admittedly, we birders could probably actually see a fair chunk of this 80 percent if we made the effort to look, but in a lot of cases, these birds call and sing from the middle of dense woods, marshes, briar thickets—places we’d rather not go.  Of course, if the bird making sounds in this uninviting terrain is one that is new or especially exciting to us, we’re more than happy to make the effort to actually see it, even if it means braving poison ivy, saw-edged marsh grasses, skin-ripping greenbriar, ticks, mosquitoes, and venomous snakes; or maneuvering more mundane obstacles such as fallen trees, creeks, holes, gnats, etc.  And, succeeding in the face of all these impediments—finally seeing the rare bird—wins the hardworking birder a valuable excuse to brag at the next bird club meeting.

But I digress.  Another great truth of birding: binoculars are excellent tools, and without them birding as we know it would be next to impossible.  However, they will not give you any extraordinary abilities in locating birds; the most they can do is magnify what you’re seeing, so that the amazing beauty and variety of birds are more apparent.  As to locating birds, the only way to improve this skill is with practice.  Even with years of field experience, though, there are some birds that will manage to elude you, or at least elude your eyes.

I’m certainly not immune to the caprices of bird behavior.  The times that I’ve been outmaneuvered by birds are too numerous to name.  Sometimes it is an individual bird on one particular day; other times an entire species seemingly conspires against my earnest efforts to see it.  For example, I have yet to observe The Chuck-will’s-widow and Whip-poor-will—both secretive night birds with calls proclaiming their names—up close and through binoculars.  I have seen a live Chuck-wills-widow in the wild—it flew up from the road in front of the family car one night.  I saw just enough of its brown wings and white-bordered tail to positively identify it.  These birds’ secrecy is part of their mystique, though, so I’m perfectly happy to just listen to their rhythmic, intriguing nighttime songs, and if I happen to see one in full view someday, so much the better.

Other nocturnal birds like owls also prove elusive.  However, since owls are generally large and hunt from relatively prominent places—not impenetrable thickets like the haunts of the Chuck-wills-widow and Whip-poor-will—they are usually a little easier to observe.  Where I live in Macon, there are Great Horned Owls that live and hunt around the pastures and backyard pecan orchards.  I have seen them on a number of occasions, but more often I hear their resonant hoots, especially on moonlit nights in late winter when the trees are bare.  It’s a very comforting sound, and it foretells the owls’ courtship and eventual nesting, since these charismatic hunters breed and raise young very early in the year.

Sometimes vocal but difficult-to-see birds can be very frustrating.  The arrival of spring brings lots of migrating songbirds, many of which choose to proclaim their territories through song from the tops of the very tallest trees.  Then, it is literally a pain in the neck to try to see these birds, craning your head back as you look through your binoculars, trying to focus on the five-inch long warbler flitting forty feet above you as it sings its squeaky melody.  Of course, it could be worse; a lot of warbler songs are too high-pitched for some people to hear—the songs of Blackpoll, Bay-breasted, Black-throated Green, and Blackburnian Warblers, for example.  Even John James Audubon, one of the founders of American ornithology, is said to have had difficulty hearing the songs of a number of birds, especially wood-warblers.  On the other hand, several warbler species have very loud songs and are relatively easy to see; go into a swampy woodland, and you may see and hear a vivid yellow Prothonotary Warbler making its shrill tweet tweet tweet tweet song in the deep, gloomy shade of the cypress trees.  I promise you, it’s an amazing experience.

One of my favorite warblers, interestingly, is one that I haven’t actually seen more than a few times.  Not that that’s anything unusual: Swainson’s Warblers are notoriously tricky to see.  One of these sightings was of a bird flying away after I attempted to creep on it while it sang in a thicket.  More recently, this year I heard a Swainson’s Warbler in an overgrown wood during a spring migration survey.  After tallying it, I decided to walk through the dense undergrowth in hopes of spotting it.  Sure enough, as soon as I deduced what direction it was in, the bird moved to another spot and began its loud, ringing song again.  Despite the frustration it sometimes provokes in me, this incredibly secretive behavior coupled with the interesting song is one of the reasons I find the Swainson’s Warbler so fascinating, and I always enjoy encounters with them, visual or otherwise.

Probably you can think of at least a few birds whose sounds are particularly meaningful to you in some way.  Maybe they evoke fond memories; or are associated with certain seasons or times of day; or perhaps are simply beautiful, amusing, awe-inspiring…the list goes on.  The robin’s hurried morning warblings, the mockingbird’s nighttime virtuoso recital, the softly lilting tur-a-lee of the bluebird, the energetic drummings of woodpeckers, the shrill scream of a Red-tailed Hawk, the echoing honks of migrating geese—these and countless other calls not only hold special significance to birders, but are familiar sounds in our day-to-day relationship with the natural world.  Even something as seemingly mundane as a crow’s guttural caw caw can bring a lot of interesting feelings to an observer.

Seeing birds is always a pleasure, but sometimes it helps to just stop and listen to them as they go about their lives.  This can be difficult; it’s hard to resist the impulse to search for a bird that you can hear but not see (after all, this is bird-watching), but even hearing birds fills you in on interesting aspects of their ecology, enables you to identify them, and just makes birding more fun and meaningful.  Another thing to keep in mind: although you can see the birds that are right in front of your eyes during birding jaunts, their songs are all around you.