Fall Shorebird Migration

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I live on the Delmarva Peninsula.  It is aptly named since it encompasses Delaware to the east, the Eastern Shore of Maryland to the west, and Cape Charles Virginia at its southern tip.  It’s bordered by Delaware Bay and the Atlantic Ocean to the east and the Chesapeake Bay to the west.  Delmarva is a flat, rural lowland with abundant farms and tidal wetlands.  There is not a rock in sight as the glaciers of the last Ice Age never made it this far south.  All in all it’s a perfect stopover and refueling site, or even a final destination for migrating shorebirds.  There are 50 species of shorebirds that breed regularly in North America and 217 species worldwide, just a small percentage of the total avian population of over 10,000 species.

Piping Plover

Piping Plover (Charadrius melodus)    click on any photo to zoom

The spring and fall migrations of shorebirds are completely different animals.  In spring the birds with raging hormones are making a mad dash to arctic and sub-arctic breeding grounds.  They follow the 35 degree isotherm to ensure liquid water and insects upon arrival.  Males and females must arrive at nearly the same time to mate, establish territories, build nests, lay eggs, and raise the young, all during the short, two-month arctic summer.  Fall migration, on the other hand is a much more leisurely trip south spanning several months from late June through November.

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Ruddy Turnstone & Black-bellied Plover (Arenaria interpres & Pluvialis squatarola)

The birds that abandon the arctic first and head south, even in late June, are the unsuccessful breeders and nesters.  If their first attempt fails due to weather, predation, etc., there is simply not enough time to try again.  Better to head south early and hope for better luck next year.  Some species send one of the parents south (either the male or female) as soon as the eggs are laid leaving the other to sit on the nest and raise the hatchlings.  Luckily shorebird chicks are more precocious than most birds walking, feeding themselves, and flying at an young age.  The abiding  parent will also migrate relatively early leaving the offspring behind to gain strength.  Amazingly the juveniles will head south one month later, often flying thousands of miles to their wintering grounds without any adult supervision.

Black Skimmers

Black Skimmers (Rynchops niger)

There has been speculation about the reason for an early fall migration from the tundra, even though there are still abundant insects and other food sources.  Some have suggested that the ancestors of these birds were tropical or neo-tropical and only began migrating northward to find new and safer breeding grounds as the glaciers retreated and climate warmed at the end of the Ice Age.  Thus, their hearts are really in the south, to which they return to ASAP when their biologic duty is done.

Wilson's Plover

Wilson’s Plover (Charadrius wilsonian)

There is species-specific timing to the fall migration.  After the non-breeders, you’re apt to see adult Least and Semipalmated Sandpipers, Yellowlegs, and Dowitchers passing through the Mid-Atlantic region as early as the first of July.  There is a somewhat predictable parade of following species, with Dunlins being an example of a late migrant, peaking here in October and November.

Long-billed Dowitcher

Long-billed Dowitcher (Limnodromus scolopaceus)

August is a popular month for observing the shorebird migration as most of the other bird groups have not yet felt the call.  Just be prepared for some confusing fall plumages.  Some will still have their breeding plumage while others will be in winter garb or a combination of both.  Add in the juvenile plumage and potential sex differences and you have some real ID challenges.  There’s also always a chance you might see a vagrant, often a lost juvenile far off course.  If you need a good reference book for these birds I recommend “The Shorebird Guide” by O’Brien, Crossley, and Karlson.

Black-necked Stilt

Black-necked Stilt (Himantopus mexicanus)

You often hear of the amazing distances covered by these migrating shorebirds.  Hudsonian Godwits are thought to fly 8,000 miles NON-STOP between breeding and wintering grounds.  Other shorebirds “choose” a more conservative approach and forgo the longer trip to Central and South America.  The Piping Plover, for instance breeds along the Atlantic seaboard from Massachusetts to Georgia and winters in Florida.  Wilson’s Plover both breeds and winters in Florida.  The Purple Sandpiper is the most hardy of the “locals” wintering along the rocky Atlantic coast all the way up to southern Newfoundland.

Sanderlings

Sanderlings (Calidris alba)

The ubiquitous and seemingly mundane Sanderling has its own migration story.  This small wave-chasing shorebird is seen in flocks on virtually every sandy beach world-wide.  It lacks a hind toe as a special adaptation allowing it to outrun the surf.  These birds breed far to the north in the arctic islands of Canada, Greenland, or Siberia and in this hemisphere choose various temperate wintering shorelines in both North and South America.  While some of Sanderlings choose a short migration route, ornithologist have discovered that others circumnavigate the entire Western Hemisphere, leaving the breeding ground in the fall and flying along the Atlantic coast to Chile and Peru.  In the spring they return north along the Pacific coast and central corridor, finally ending up at their original breeding site in northern Canada.

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Delmarva shorebird (Erratum maximum)

Our local baseball team, a farm club for the Baltimore Orioles, is appropriately called the Delmarva Shorebirds.  It seemed like the perfect name until they chose the team logo–they really needed a birder on that committee.  I would have suggested a Sanderling, a Piping Plover, or maybe even a Black Skimmer.  Instead they ended up with some stylized nonentity that looks like a cross between a Pileated Woodpecker and a Raven.  It’s clearly not a shorebird.  C’est la vie.

Cape May Hawkwatch Platform

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If you had to rate birding hotspots or favorite destinations for the eastern United States, Cape May would likely be at the top of the list.  This southern-most tip of the New Jersey peninsula was named for Captain Cornelius Jacobese Mey who explored the region in 1623.  The generations of fishermen, mariners and whalers have slowly given way to vacationers enjoying the beautiful beaches and myriad Victorian gingerbread houses gracing quaint tree-lined avenues.  But I went to Cape May for the birds, who are not there to admire the architecture.

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Merlin (Falco columbarius)

In a relatively small area you’ll find a variety of habitats including woodlands, grassy fields, salt marshes, freshwater ponds, low scrubland, and sandy beaches attracting a large variety of resident and migrating birds.  Almost anything is possible during fall migration in Cape May as the northwest winds push the vast Atlantic flyway eastward toward the coast and the birds are funneled southward until they arrive at land’s end and the formidable Delaware Bay and ocean.  The smart ones rest and feed for a few days, enjoy the scenery, and create a show to remember for us birders before continuing over the water.

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Laughing Gull (Larus atricilla); the area boasts the largest breeding population of this gull–no joke.

Cape May is one of the only places I know where the birder, dressed in our weird outfits and draped with our equipment, does not draw that quizzical apprehensive stare.  You’ll see many birders and guided tour groups daily throughout the town, and may even run into the celebrities, authors, and gurus of our hobby.  There are far too many birding sites in the area to discuss here, but one of my favorites is the Hawkwatch platform near the lighthouse at Cape May Point State Park.

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Red-tailed Hawk (Buteo jamaicensis)

Hawks have been watched and counted there for years but the counter became a formal paid position of the New Jersey Audubon in 1976 when they hired 24 year-old Pete Dunne.  The stump of an old telephone pole was the first platform, soon replaced by a plywood table built by Dunne himself.  Despite these humble beginning he, of course, is now one of our most accomplished birders and authors.  The platform itself has also grown to become a large, multi-tiered edifice and famous destination for birders, hosting 20,000 visitors in 2015.  It’s in a perfect location halfway between the dunes and beaches to the south, the tree line to the north, and directly faces a shallow saltmarsh to the east.  Curiously the migrating kestrels tend to hug the shoreline while the hawks pass east to west over the tree line.  Just to the west is the famous lighthouse, restrooms, visitor center, and plenty of free parking.

Hawk-Watch platform and counter

Hawk-Watch platform and counter

Think of a sports bar on a Sunday afternoon in autumn.  There are different football games playing on multiple large screen TV’s while “experts” multitask, keeping one eye on one game and the other eye elsewhere; at the same time debating over a cold beer on the wisdom of the last play call and the preferred strategy for the next.  That’s the hawk-watch platform during autumn migration; just substitute birds for the TV pigskin and bottled water for the beer.

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Herring Gull (Larus argentatus)

On the top tier of the platform and far to the right you’ll find the official counter.  He or she is the one constantly scanning the sky and often calling out the birds while they are still specks in the distance. “Merlin heading to the right between the two fluffy clouds, one binocular field-of-view to the left of the lighthouse!”  They amaze with their knowledge of characteristic flight patterns, wing flapping, and silhouettes, but you soon begin to learn their techniques and try your luck.  If you’re brave you may even call out a bird sighting yourself, but be prepared to be politely corrected if you blunder.

American Kestrel

American Kestrel (Falco sparverius)

As in the sports bar you can choose to just sit quietly and enjoy the birding banter.  Someone on the right is reliving an amazing count total from the past while someone on the left is describing recent trips to birding hotspots in Arizona and Maine.  Another expert is holding forth on the best camera, lens, or field guide while on the lower tier the Swarovski Optik representative (they are the corporate sponsor of the count) is hawking their wonderful scopes and binos.  While just sitting there I learned about the distinguishing dark carpal bands on the Common Tern and how to recognize the aggressive flapping flight of a Merlin, the “falcon with attitude”.  One made a low flyover right in front of us unsuccessfully chasing a fleeing sandpiper across the pond.

Greater Black-backed Gull

Great Black-backed Gull (Larus marines); look carefully to see his songbird prey

They count more than hawks from the platform with plenty of songbirds, waders, gulls, and shorebirds also called out.  My days at the platform were relatively quiet with a warm southern wind blowing in from the bay.  However, the day before I arrived they counted 91 American Kestrels and two days earlier had 325 Bobolinks coming in on more favorable NW winds.  The most common bird of prey which I saw was the Merlin, coming in seemingly every 10 minutes one mid-morning.  Extremely “big days” are possible.  Pete Dunne counted 11,096 Sharp-shinned Hawks and 9400 Broad-winged Hawks on 10/4/1977!  Oh, to have seen that!

Peregrine Falcon (Falco peregrinus)

Peregrine Falcon (Falco peregrinus)

There is no such thing as a bad birding day at Cape May.  And if the birds seem scarce just check out the “Hawkwatch Sports Bar” and you’re sure to pick up some tips or meet a celebrity birder.  There’s a counter there everyday from dawn to 5PM,  September 1 till November 30.

Staccato Summer

Red-bellied WP

Red-bellied WP, Melanerpes carolinus

 

I was under the mistaken impression that everyone loved woodpeckers with their striking black, white and red plumage, and distinctive behavior.  My sister-in-law has taught me otherwise.  She has a Red-bellied that keeps her awake at night by its drumming and drilling on the side of her cedar shake home.  Countless holes through the siding and sheathing and even into the insulation have caused mounting repair bills.  She now hangs gaudy Christmas tinsel year-round on the corner of the house to scare them off, all to no avail.  I’m afraid that more lethal interventions are now being considered.

Downy Woodpecker, Picoides pubescens

Downy WP, Picoides pubescent  (click on any photo to zoom)

Despite this I remain a strong admirer of the Picidae family of birds.  There are 25 species of woodpeckers in North America and 220 worldwide.  They vary widely in size but all have relatively short legs, long toes, and strong tails to support them upright against the tree trunk.  Their flight is rather slow and undulating.  The Flickers and Sapsuckers are migratory, depending on insects year-round, but the remainder are sedentary with a more diverse diet.  Woodpecker vocalizations are rather primitive, but loud and distinctive, often described as a descending rattle.

Red-headed WP

Red-headed WP, Melanerpes erythrocephalus

But where they really excel is with their staccato drumming ability–sorry sister-in-law.  I used to think that this was just the sound made by the bird’s search for food in the bark.  In reality it is a much more sophisticated communication tool used also for staking out breeding territory, attracting a mate (and maintaining the bond), and general communication–“I’m on my way home with more bugs.”

Yellow-bellied Sapsucker

Yellow-bellied Sapsucker, Sphyrapicus varius

The cadences are somewhat species specific.  Flickers and Sapsuckers have random, discontinuous patterns sounding like Morse Code.  The large Pileated has a loud, deep sonorous drumbeat that slowly diminishes in amplitude as it increases in frequency.  The Red-bellied drums at 19 beats per second, the Downy at 17 bps, while the Yellow-bellied Sapsucker starts with a short roll, pauses, and ends with two brief rolls of 2-3 beats each.  I guess I’ll have to consider adding a stopwatch to my birding paraphernalia.

Pileated WP

Pileated WP, Dryocopus pileatus

The force that a woodpecker generates by banging his head against a tree trunk is many times the maximum force that a human head and brain can survive.  There are a number of adaptations that make this possible.  The bird’s skull is thick and highly trabeculated, the neck muscles are strong, and the beak itself is slightly flexible, all helping to dissipate the force of the blow.  They also have a third inner eyelid to keep the eyeball from popping out at impact.

Nutgall's WP

Nuttall’s WP, Picoides nuttallii

The Hairy has the most bizarre adaptation.  This bird has a very long and sticky tongue to reach deep into the tree.  The tongue is retractable via an elaborate system of pulleys and muscles into a long tunnel which extends from the throat, encircling the base, back, and top of the skull, finally ending in the front at the base of the upper mandible.

The neat Sapsucker rows; apparently it doesn't harm the tree

The neat Sapsucker rows; apparently it doesn’t harm the tree

The Sapsuckers peck hundreds of perfectly parallel holes, encircling the tree and creating “sap wells”.  The birds feed on the sap but also on the myriad insects it attracts.  The endangered Red-cockaded also thrives on the sap of the large live pines of the South.  In fact I found this uncommon bird in Florida by first locating the large hardened resin patches on its preferred trees and then waiting patiently for the bird to show up.

Acorn WP

Acorn WP, Melanerpes formicivorus

The Acorn is a communal clown-like bird appropriately found on our “Left Coast”.  It forms small breeding flocks of several males and females along with some non-breeding young adults, all sharing in the incubation and feeding duties.  The bird is famous for the precisely drilled holes, each packed with a single acorn hoarded for future consumption.  These “granary trees” have been known to hold up to 50,000 acorns and are jealously defended by the commune.

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Ivory-billed WP, Campephilus principalis               by John James Audubon

I suspect all birders are familiar with the Ivory Woodpecker story. The last sightings of this large, glorious bird were in the bottomland forests of Louisiana and Arkansas in 2005.  But you’ll notice that all the extinct designations are qualified by “presumed”, “probably”, and “likely”.  Whenever I’m birding in the forests of the deep South and a Pileated flies by, I always take an extra glimpse of the bill color.  You just never know.

Book Review: Pilgrim at Tinker Creek, by Annie Dillard

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Pilgrim at Tinker Creek by Annie Dillard, published by HarperCollins Publishers, copyright 1974, 290 pages.

In the spirit and words of Henry David Thoreau, Annie Dillard went to her Walden Pond, Tinker Creek, “because I wished to live deliberately, to front only the essential facts of life, and see if I could not learn what it had to teach, and not when I came to die, discover that I had not lived.”  This remarkable Pulitzer Prize winning book by a 28 year old will impress and inspire.  Like Thoreau, “I have traveled a good deal in Concord”, Tinker Creek is her local unassuming haunt in the suburbs of Roanoke, Virginia. Dillard is the pilgrim to this sacred place, a small creek with island, winding its way through pasture and wood, in the foothills of the Blue Ridge Mountains.

Red-winged Blackbird

Red-winged Blackbird, Agelaius phoeniceus

It is a book of her fascinating natural observations, but then buckle your seat belt and hold on tight as she takes you soaring into the meaning, or lack thereof, of it all. It’s a pilgrimage of the mind dipping into cosmology, theology, epistemology, and even quantum mechanics before bringing you back home, somewhat exhausted.  She intends to “tell some tales and describe some sights of this rather tame valley, and explore, in fear and trembling some of the unmapped dim reaches and unholy fastnesses to which those tales and sights so dizzyingly lead.”

European Starling

European Starling, Sturnus vulgaris

This is obviously not a birding book although she does relate some interesting bird encounters.  There was the “Wood Duck flying like a bright torpedo that blasted the leaves where it flew.”  Or the Mockingbird with the white-striped tail fan diving straight down, seemingly just for the joy of it.  Or the flock of migrating Red-winged Blackbirds hidden in the Osage orange.  Or the annoying flock of thousands of European Starlings in the valley.  At wits end a hunter went out with shotgun and fired into the flock, killing three.  Asked if that had discouraged the birds he replied after some reflexion, “those three it did.”

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A quiet contemplative day of birding?                           Photo by A. Sternick

Birders, like Dillard relish being out there day after day to see what develops, observing closely and carefully, and returning with some pearl or new insight.  As she says, “beauty and grace are performed whether or not we will or sense them.  The least we can do is try to be there.”

Wood Duck

Wood Ducks, Aix sponsa; female and juveniles; I still waiting for a good close shot of the colorful male

Insects seem to be her special interest and several tales lead you into that strange world.  There’s the small frog on the bank that slowly involuted into a pile of skin right before her eyes.  It was being sucked dry by the hidden Giant Water Bug that had injected its dissolving enzymes and was now enjoying the nourishing broth while leaving the skin behind.  Then there’s the female Praying Mantis slowly devouring her sexual partner during coitus until all that’s left is his sexual organ, still fulfilling its purpose.  She has a special place in her heart for spiders.  “Any predator that hopes to make a living on whatever small creatures might blunder into a four inch square space in the corner of my bathroom…needs every bit of my support.”

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Northern Mockingbird, Mimus polyglottos

I appreciated the section about quantum mechanics and the Heisenberg Uncertainty Principle which says that the process of observation itself alters what is being observed.  This led to a college term paper for me years ago.  I won’t attempt to review the theology of this text, New or Old Testament, Koran, and others.  Nor will I tell you what the author concludes about the universe; is it brutally cruel or kind, chaotic or orderly; actually I’m not sure what she thinks.  I’ll have to read it again.  Some may find Tinker Creek too obtuse.  I suggest just plowing through those passages and come back to them later for a fresh look with a clearer head.  There’s much here to ponder.  “Knock; seek; ask.  But you must read the fine print.”

Red-winged Blackbird

Red-winged Blackbird, Agelaius phoeniceus

Some critics, including the author herself in recent years have complained about excessive verbosity in some passages–her style has later become more succinct.  You can also take the “deeper meaning” approach to the extreme, but remember when this was written.  We were all reading Hermann Hess and listening to Jimi Hendrix back then so I’ll forgive the influences of the time.  I still wonder how I overlooked this 1974 book for so many years, recipient of prizes and much acclaim.  Better late than never.

Where Have All the Swallows Gone?

Tree Swallow

Barn and Tree Swallows

Gliding, diving, graceful birds

Acrobats in flight.

On a boring day in May, June, or July you can always sit on the porch with a cool drink and watch the swallows.  This year the Tree Swallows won the annual competition for the birdhouse down by the creek, the one with the water view, and the Bluebirds were again relegated to the other two houses along the driveway.  I don’t pick favorites as both have great appeal.  The birdhouse by the water does have some issues as the smart Fish Crows from the neighbor’s trees are always poking their large bills through the hole, trying to snag a hatchling for lunch.  The parents do a brave job driving off the much larger crows, but I fear they are not always successful.  That doesn’t seem to stop the swallows from coming back here year after year.

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Barn Swallow, Hirundo rustic,                   click on any photo to zoom

The entertainment is their airshow.  Swooping, sharp corners, straight up, diving low over the grass and river, catching insects, eating and drinking, even in flight.  In my book only the terns can rival the swallows in aerial acrobatics.  The Tree Swallows arrive first in the spring to stake out a nesting cavity, and stay later in the fall since they are the only swallow that can also feed on berries when the bugs are no longer plentiful.  The later arriving Barn Swallows almost exclusively build their mud nests on man-made structures–in my yard that’s the underside of the boat dock.

Eastern Bluebird

Eastern Bluebird at the “loser’s” house

The “Barnies” are the only North American swallow that has that deeply forked swallow tail.  It, plus the chestnut colored throat make the ID easy.  The Tree Swallows are striking birds with pure white below and metallic blue or green above, depending on the light.  These are the most common swallows in the East, but keep an eye out for the Bank S. with its dark chest band, the less sociable and more bland Northern Rough-winged S., and an occasional Cliff S. with its buff rump and forehead.

Tree Swallows

Tree Swallow flock

Then one evening in late July you notice they’re gone.  No fanfare or goodbyes, just gone, show’s over.  The birdhouse and dock are vacated.  And why did they leave so early?  There are still plenty of bugs, warm weather and sunshine, and maybe even enough time to raise another brood.  But I’ve learned that they are not gone.  The swallows haven’t really left for the season yet, but have changed their venue.  Just travel a few miles east to the inland fields with power lines or the vast tidal marshes along Delaware Bay and you’ll find them again.  You’ll see flocks, sometimes huge mixed flocks of swallows, no longer interested in breeding but now more intent upon consuming large volumes of insects and storing up energy for the coming fall.

Northern Rough-winged Swallow

Northern Rough-winged Swallow, Stelgidopteryx serripennis

The fall migration is a much bigger deal than its spring counterpart.  A successful breeding season will swell the flock many times over the number of birds that arrived the previous spring.  But there’s danger ahead.  Its been reported that the mortality rate for songbirds during the fall migration and at the wintering sites may be as high as 85% due to disease, predators, accidents, weather, etc.

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Tree Swallows, Tachycineta bicolor

 Flocking prior to and during fall migration, and continuing all winter, may in part be a safety mechanism to confuse predators with visual overload.  As opposed to most songbirds the swallows migrate in these large flocks during daylight, perhaps relying on visual clues for guidance.  This also allows them to feed on the fly.  The Tree Swallows will actually undergo a gradual molt during the trip to South Florida, the Gulf coast, Cuba, or Mexico, whereas the “Barnies” wait to molt until they have arrived at the wintering grounds in South America.

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Coastal flock prior to fall migration

So the swallow’s sojourn in their summer breeding grounds appears to be a two part affair.  First mate, nest, and raise the young.  But when that’s accomplished congregate in great numbers, fellowship, teach the juveniles advanced flying skills, and build up fat reserves for migration.  And when the mysterious word is spoken, whether it’s hormonal, sunlight, or temperature, be ready to head south en masse.  Their return in the spring will not be in massive flocks but rather in smaller groups of survivors, coming north to start the cycle all over again.

Do Birds Retire?

Red-shouldered Hawk

Red-shouldered Hawk, Buteo lineatus

 

As I approach that golden age of retirement my birding hobby causes me to look to the avian world for guidance.  Do birds retire and perhaps seek that perfect habitat where food and water are plentiful and the temperature ideal all year long?  Do they give up those long migrations and the work of nesting and breeding?  Do they recreate with other aging birds, have more time for song, or perhaps help with raising of the grand and great-grand chicks?  Birds, I know do not crave a large nest egg; for them that just signifies the nefarious work of a parasitic cowbird and means another large mouth to feed.  (See earlier post “Birds Behaving Badly / Brood Parasites”, 8/22/2015)  In short, is there a golden age for birds?

Ruby-crowned Kinglet

Ruby-crowned Kinglet, Regulus calendula (click on any photo to zoom)

There seems to be two distinct approaches to this issue in humans; those who want to keep working or must work until they die in the saddle, and those who crave and can afford the free-time of retirement.  You can’t explore these issues for birds until you figure out how to determine the bird’s age, and they don’t make that easy.

Indigo Bunting

Indigo Bunting, Passerine cyanea

Bird size is not a reliable dating tool, nor is bird song.  Some have observed that second year males often have weird or incomplete versions of the adult song, but you can’t rely on it for dating.  Early dating by plumage is straight forward, using natal down and the rapid progression to juvenile plumage, which is usually duller than the adult’s and often spotted or striped.  But by late summer, fall, or early winter, depending on the species, the “first winter” plumage develops which is usually very similar to the adult.

White-eyed Vireo

White-eyed Vireo, Vireo griseus

Judging the age of adult birds then becomes much more difficult.  The annual or biannual molt makes the shabby and worn out feathers all new again, like repairing the wrinkles of age.  Wouldn’t a yearly face-lift or tummy tuck be great?  Luckily some birds, gulls in particular, have a yearly progression of plumages allowing first year, second, third, and adult age designations.  Learning these variations is difficult and requires a good guidebook or an experienced colleague.

Brown Pelicans

Brown Pelicans, Pelicans occidentals (adult above and juvenile below)

Another dating technique is called skulling.  One can observe the air cavities in the bird’s skull by wetting and separating the feathers.  The maturing skull apparently goes through a specific and progressive pattern of pneumatization and maturation, visible through the bird’s thin skin.  This is obviously a tool for ornithologists–don’t try this at home.  That leaves banding, the most definitive technique in determining the birds age, but again a technique for the experts.  These basic facts are now known:  birds in the cooler temperate zones live shorter lives than those in the tropics, rural birds live longer than urban birds, large birds live longer than small birds, and young, inexperienced juveniles have the highest mortality rate of all.

Mottled Duck & Ducklings

Mottled Duck & Ducklings, Anas fulvigula

I was surprised to learn that the annual mortality of passerines was 70% in the temperate zones.  The longevity record for the Bald Eagle and Osprey is 22 years, 16 years for a Northern Cardinal, and 7 years for a House Wren.  But these were the lucky ones.  Message to birds:  avoid risky juvenile capers, leave the city and head to the tropics and stay there, and don’t volunteer to be a canary in a coal mine or a clay pigeon.

House Wren

House Wren, Troglodytes aeon

D.J. Holmes and others, writing in “Experimental Gerontology”, has noted that birds have relatively longer life spans compared to similar sized mammals, especially given their warm body temperatures, rapid heart rates, high glucose levels, and high metabolic rates.  These are usually harbingers of rapid aging, but not so with birds.  Some seabirds in particular age very slowly and actually increase their reproductive activity with age.  Apparently birds have evolved specific adaptations to offset the cell damage caused by oxidative and glycosylative compounds, mechanisms not found in mammals.  Is there a hidden “Fountain of Youth” under all those feathers?

Dark-eyed Junco, AKA Snowbird

Dark-eyed Junco, Slate-colored, Junco hyemalis (AKA Snowbird)

So it turns out that birds do not retire and enter a life of leisure but rather press on or even increase their activity and fecundity with age.  That is until they just drop, fly into a window, or are snatched away by a more agile hawk or owl.  I’m sorry to learn this, but maybe we humans can adapt some of their techniques for staying young.  Life in the tropics sounds good, so I for one will become a “snow bird” and head south this winter.  I’m also interested in those avian chemical adaptations.  Maybe there’s an investment opportunity lurking here.

The Least Birds

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“Least” is the superlative on the short end of the scale.  It’s a modifier that may be complimentary or derogatory but in the birding world it just describes size.  I was noticing some terns roosting on the dock pilings this week.  The Royal was large and obvious, while the smallest were more vocal and active, hovering and diving while the others just watched.  These were Least Terns and brought to mind the other common “least” birds, the sandpiper, bittern, and flycatcher.

For me the Least Terns were the easiest terns to learn and ID, mainly due to their size and an obvious marking.  The ID’s become much muddier for the next size up when you have to deal with the Common, Forster’s, and Roseate Terns with their subtle differences.  In addition to being our smallest tern, that white chevron on the forehead on breeding adults is unique.  The Little Tern is a similar-appearing East Coast vagrant from Europe, but other than that potential confusion, the Least Tern is usually an easy ID.

Least Tern, Sterna antillarum

Least Tern, Sterna antillarum

This little bird has been losing it’s competition with bathers, beachcombers and condos for nesting sites on the beach, but now you do find some roped-off dunes.  The bird’s innovative and resourceful impulse has led it to “protected” nesting on the gravel roofs of shopping plaza, including our local Acme.  I guess there is some benefit to all these big box stores.  Thankfully the milinery hunters of the 19th century are no longer a threat.  Say goodbye to this bird in late summer as it completely leaves the mainland U.S. and northern Mexico for unknown wintering grounds further south.

Least Sandpiper, Calidris minutilla

Least Sandpiper, Calidris minutilla

The Least Sandpiper also comes in as the perceptible light-weight of the peeps.  The guidebooks only list it as 1/4 to 1/2 inch smaller than the Western and Semipalmated Sandpipers but the size difference is noticeable when you see them in a group.  Often however, this bird congregates in small feeding flocks away from other larger shorebirds in sheltered coves and along marsh edges. It’s the most common sandpiper to be seen on small inland lakes.  I find that the pale yellow legs is the most helpful field mark–the other peeps have black legs.  I know the caution about muddy legs obscuring the yellow, but you usually can find one bird in the flock who likes to keep her legs clean.

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Least SP; also notice slightly drooping bill tip and more brown than other peeps

The birds breed in Canada and Alaska but appear along each coast and the Great Lakes in mid-June, hanging around through September.  I find them in Florida and the deep south all winter.  I’ve learned from experience and fellow photographers that you really need to get low on the beach, kneeling or lying prone to get good shots of the shorebirds.  I usually just kneel.

For the other two “least” birds the modifier is valid for not just their size.  The Least Flycatcher and Least Bittern are among the least often seen, least photographed, and least properly ID’ed birds, at least for me.  Forgive me for showing photos of related birds only–I’ll keep stalking the others for decent shots.

Great-crested Flycatcher, Myiarchus crinitus

Great-crested Flycatcher, Myiarchus crinitus

The Least Flycatcher is common here but easily confused with the other 4 members of the genus Empidonax that are also seen in the Eastern U.S.  They all have wing bars and eye-rings and their size differences are only measured in 1/4’s of inches.  This is where “advanced birding” techniques apply.  The best differentiaters are their songs and habitat preferences, but you’re often left with just calling them all “Empids”.  The Least FC prefers the partly open edges along woods and has a loud “che-beck, che-beck…” song.

Green Heron

Green Heron, Butorides virescens

I saw the elusive Least Bittern at a distance in the STA5 water control area in south/central Florida in 2012 with a large group of experienced birders.  Despite its relative abundance the wonderful camouflage and secretive feeding habits make it one of the more difficult sightings.  I think it’s closest look-alike is the Green Heron rather than the larger American Bittern.  I’ll show you photos of both–it’s the least I can do.

American Bittern

American Bittern, Botaurus lentiginosus

Summer Solstice Birding

Red-headed Woodpecker

Red-headed Woodpecker

 

2016 has been strange in many ways.  Add one more example–it’s the first time in nearly 70 years that the full moon and solstice have fallen on the same day, June 20.  Algonquin Indians called this rarity a “Strawberry Moon” since it occurred at the height of the strawberry harvest.  The solstice (from Latin sol, meaning sun and sistere, meaning to stand still) is the day in the earth’s orbit when the 23 degree tilt and the northern hemisphere are directly toward the sun, the sun reaches its maximum elevation in the sky, and daylight lasts the longest.  In other words, it’s all downhill from here.

Great Blue Heron

Great Blue Heron

To celebrate, I went birding.  June birding is like June Christmas shopping–there are no crowds but the pickings are rather slim.  Gone is the phrenetic excitement of spring migration when you feel you’ll miss something if you’re not out there everyday.  Instead you have the quieter breeding, house-keeping, and chick-rearing of the birds that have chosen to live and work in your neighborhood, fostering a special attachment to these “locals”.

Osprey

Osprey, click on any photo to zoom

Summer birding is all about moisture.  As a northerner I first looked for a job in the south 35 years ago.  During an interview in Charleston SC I commented on the humidity.  “If you want to live down here, young man, you’ll just have to get use to feeling sticky.”  So I took a job a little further north on the Eastern Shore of Maryland.  Combine sweat, bug spray, and suntan lotion with standing water from a rainy spring and you have sticky birding, even here in the shallow south.

male Orchard Oriole

male Orchard Oriole

Along our tidewater creek on the Chesapeake we were debating the other evening as to which bird was contributing the most decibels to the summertime din of birdsong.  It was a draw between the nearly constant screeching of the Osprey, the piercing trill of the Red-winged Blackbird, and the extensive repertoire of the the Northern Mockingbird.  The Mocker probably wins the prize for duration as he continues the concert long after sunset.

female Orchard Oriole

female Orchard Oriole

The photos in this post were all taken this week at the Blackwater NWR in Dorchester County, Maryland, a few miles south of here.  There was nothing unusual seen but the day offered a chance to work on photography techniques.  This site is my most reliable location to find the gorgeous Red-headed Woodpecker, a bird that alluded my camera lens for years.  I was the only birder there, the horse flies and mosquitoes were held at bay by the strong NW winds which came in following the priors night’s strong storms, and the daylight was long–the longest of the year.

Red-winged Blackbird

Red-winged Blackbird

We were having a glass of wine on the porch at sunset this week when two Mockers landed on the lawn right in front of us and began literally rolling over each other in the grass.  I’ve seen birds mate standing up, sitting, swimming, and even while flying, but have never seen this rolling caper.  It became even stranger when the third bird flew in.  My literary spouse put it all into perspective when she reminded me of Oscar Wilde’s famous quote, “I have no objections to anyone’s sex life as long as they don’t practice it in the street and frighten the horses.”

Red-headed Woodpecker

Red-headed Woodpecker

Those Pesky Canada Geese; Why Won’t They Leave?

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Branta canadensis

 

The story of the increasing numbers of non-migrating, resident Canada Geese is more interesting than just “bird slothfulness”, and may be an example of the unintended consequences of human intervention, bird adaptation, and evolution in action.  These year-round birds also generate strong human emotions and responses, similar to when a house guest overstays their welcome.

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The migratory geese

My first childhood memory of Canada Geese was when my father pointed out the honking V’s, high overhead as we made our cottage ready for winter in Upstate New York.  When I moved to the Chesapeake 33 years ago they took center stage each fall, and all exited stage left each spring, leaving us with fond memories and anxious for their autumn return.  Back then they were very welcome, but things have started to change.  The Branta canadensis PR department must re-examine their new behavior before it’s too late.

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Click on any photo to zoom

There are about 5 or 6 million Canada Geese in North America with the resident non-migratory population now greater than 50% of the total.  In 1900 however, Branta canadensis was in serious jeopardy, mainly from hunting pressures. By 1950 the “Giant” subspecies, occidentals, was thought to be extinct.  Luckily a small surviving group was located and allowed to breed in captivity, and were eventually released back to nature, but now as non-migrating birds.  Interbreeding with other subspecies led in part to this growing population of geese that no longer heeds the call of the north each spring.

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And how can you blame them?  1500 miles is a long way to fly if you don’t need to.  When you get there, tired and hungry, you must immediately mate, build your nest, and fight off predators, only to make the return flight south in 6 months.  The resident geese however can enjoy a year-long stable climate and breeding conditions, beautiful grassy lawns for feeding and ponds for swimming, few predators, and only have to take short, low-altitude flights.  They’ve boldly adapted to lawn mowers, dogs, picnickers, golfers–no problem for them.

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A picnic in our front yard.

The problem is for humans.  Denuded lawns, goose droppings on the putting surface and elsewhere, polluted ponds and pools, health concerns, and airplane collisions are some of the issues.  The birds are protected by the Migratory Bird Act but some efforts to reduce the population have been tried without significant success.  Many states have an early hunting season, before the migrating geese arrive.  Nest and egg destruction, harassment, habitat management, etc. have all been tried to little avail.

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Early family life

It interesting to note that while the migratory geese are only breeding after they arrive in Canada, the resident geese breed down here–they don’t interbreed and their gene pools do not mix.  I suspect someday we will begin to see morphologic differences such as smaller migratory birds with stronger flight muscles, as well as genetic differences when mutations occur and are passed on only along the isolated lines.  I think I can already detect the fatter and bolder resident birds when the flocks mix here in the winter.  Someday, in perhaps several million years, we’ll see a distinct separation of two species.

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Teen age brood. Where are their headphones, cell phones, and tattoos?

This spring we had two families of resident Canada Geese raised along our shoreline.  I must admit it was enjoyable watching the growing families parading across the lawn each evening.  One day I found several small chicks had entered our pool but could not climb out–the parents were nearby honking loud instructions but were unable to save their young.  Here was my chance to cull the population–but I just could not do it.  I spent a long time catching the downy youngsters in my leaf net–those little buggers can really swim and dive even if that can’t fly.  I finally released them to their concerned and squawking parents, with nary a thank you I must add.  I guess I’ll just leave the culling to someone else.

What’s Up With the Martins?

Purple Martin

Purple Martin, Progne subis

The last of April and early May were remarkable for the cold, wet weather here in Maryland and throughout the Mid-Atlantic.  I heard we had 14 straight days of measurable rain and the thermometer was clearly forgetting that the spring equinox was six weeks ago.  As we pulled into our rural road, returning from a hot supper out, there was a good-sized flock of Purple Martins, maybe 25 or 30, blocking our way.  As I slowed down surprisingly only a few flew away and even those birds quickly landed a short distance further down the road as if to claim it for themselves.  I ran an obstacle course through them trying hard to straddle as many as possible.  What was going on?  These were not the usual energetic, swooping, and vocal swallows one usually sees each spring.  The next morning the martins were still on the road, but now there were several squashed bodies of those that had refused to yield to traffic.  This went on for several days and the body count mounted until the survivors finally disappeared.

Purple Martin

Martin roadblock; note the droopy tail and wings

About this same time I was at a party where friends of mine recounted another episode of strange martin behavior occurring about the same time in the cold and drizzle.  This couple are bird lovers and astute observers of the flora and fauna in their yard. They noticed a martin with unusually droopy wings perched on the porch of their Purple Martin house.  He flew away when they investigated with a ladder but one of the apartments was jammed with five other stuporous martins.  The entry to another apartment was blocked by a dead bird, and when he was removed another five birds flew out the now open door.  What’s going on?

Purple Martin

male

As you probably know Purple Martins are long distance migrants. The older scouts first arrive in the Chesapeake region in the second half of March, seeking their prior year’s nesting site.  The younger birds make the long trip from South America up to four weeks later.  The martins are the largest New World swallows and the only swallows displaying sexual dimorphism–the sexes look different. The eastern subspecies has the unusual trait of almost entirely depending upon man-made cavities for nesting.  Hundreds, perhaps thousands of years ago Native Americans in the east started hanging hollowed-out gourds to attract the sociable martins.  European settlers noticed this and expanded the practice which we continue today.  After thousands of generations of birds using these man-made nesting sites the eastern martins have essentially abandoned the use of natural cavities.

Purple Martin

Click on any photo to zoom

The concept of long distant and massive bird migrations has not always been known.  This makes sense since until the end of the 15th century we weren’t even aware of the distant continents themselves.  There was a general idea that the disappearing fall birds were hibernating somewhere, just like the frogs, turtles, and some mammals.  I’ve read old accounts of torpid spring martins that were assumed to be waking up from their winter’s sleep and wonder if they were describing the same behavior of our martins last month.

Purple Martin

Progne subis

So here’s my theory of what’s going on with the martins.  They are tough birds but after a two thousand mile migration their body weight is significantly reduced and the birds are vulnerable.  The ill-timed cold snap and rains greeted them in their already weakened state making it difficult to fly, or even avoid an oncoming car.  Martins usually forage during flight, but if they are too weak to fly hunger will compound their plight.  Possibly the flying insects they feed on were also in short supply due to the inclement weather.  I’ll bet they were huddled in the apartment and on the dark road in a last desperate search for warmth.  In the open they were clearly easy prey for predator hawks as well as the squashing cars.

Let me know if you’ve noticed similar behavior or if you have any additional thoughts.  It may well be a tough breeding year or two for the martins, at least in our neck of the woods.