Fall Shorebird Migration

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 (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.

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 (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 (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 (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 (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 (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.

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

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.

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.

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.

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

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.

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 (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.

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)

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.