Nature Notes #3: Shorebirds Arriving for the Winter

As I sit in my friend’s backyard garden a cool breeze brushes over my skin, calming me on this summer day.  Birds sing, sing, sing – invoking more calm.   Why does the sound of birds singing feel so soothing to me?

A few weeks ago the LA County bird listserve included a post reporting the first shorebirds arriving back from their breeding grounds.   Numerous species are settling in along the Los Angeles River.

One early Black-bellied Plover was reported, the mere mention bringing a smile to my face.   The Black-bellied Plover has become my favorite shorebird.  Not because of any striking or particularly colorful feature.

Instead, I’ve grown to love these birds that travel between the Arctic Circle and the Ballona Wetlands because I’ve become accustomed to their yearly arrival mid-summer, and I’ve become better acquainted with them each year as I walk the estuary levees.   And, I long to hear this bird's unique song.

On July 25 Roy van de Hoek, Ballona Institute’s resident naturalist, noted approximately 100-200 Black-bellied Plover standing on the Salt Panne in the Ballona Wetlands Ecological Reserve – the first significant sighting of the season to be reported.

Some 1,200-1,500 Black-bellied Plover Pluvialis squatarola arrive each year at the Ballona Wetlands.     The earliest arrival male parents are still deeply speckled – black and white mottled markings, with deep black bellies – feathers having been colored by nature for courtship and breeding purposes.   Mostly, we see the plovers after their feathers have toned down – grey, brown and white.  Two distinctive black spots under what appear to be armpits are visible from below when they fly.

Sometimes as I walk, I wonder, “Which of the birds I see standing so still on the rocks are the mothers?   How did the young find their way here when scientists say the parents fly ahead of them?”

The mysteries of migration are many, yet new advances in technology are informing scientists of surprising detail.  Tiny transmitters are attached to the birds’ wings, so migration tracking is more exact. 

Somehow, without a transmitter, a mother Black-bellied Plover knows her young.   Ornithologists say the call of each young bird is distinctive, and mother birds are tuned into recognizing that call.   This knowing recognition helps to make sure each baby bird is fed sufficiently while growing up on the Arctic Tundra.

The late spring/early summer of this northern birthing spot boasts an abundance of insects.   Insect calories are transferred from the beak of the mother to the baby until the young plover can feed itself.   Within a day the young are walking and feeding themselves on the insect banquet provided by the “land of the midnight sun.”   

Once the young are full-size they are ready to travel south for the winter, and soon they will be seeing the Los Angeles coast for the first time.

There are three places the plovers call home while in Los Angeles.   During the daytime they stand in the salt panne – a crusty landscape with few plants and white salt atop it when rainwater has yet to fall. Extremely social birds, except for their habits of dining alone, the Black-bellied Plovers almost always are together.   If the sight of a hawk or some other predator alarms a plover or two, they call out to each other and all lift off together, flying acrobatically as a well-synchronized flock.

Late in the afternoon the plovers move to the edges of the Ballona Creek estuary and stand among the rocks.   As the crepuscular hour arrives and the sky turns from blue to grey, the cool, clear whistles of the Black-bellied Plover can be heard.   What do these whistles signify?   I’ve often wondered – the first time I’d really paid attention to them was in 2001 when a reporter from NPR’s “Living on Earth” was visiting and those beautiful, crisp whistling sounds were captured on tape.  It’s now a sound I look forward to in late summer, fall and winter – missing it desperately while the plovers are away in their breeding grounds.

The third location the plovers go while here in LA I only recently learned.   As darkness falls these birds head to the beach where, at the water’s edge they find food with their big, round eyes.

In addition to Black-bellied Plovers other shorebirds line the estuary levee rocks that provide ready camouflage and loafing space (loafing is a term biologists use for the time birds rest from the rigors of flight and hunting for food.)  

Willet, with the straight beak and its colors imitating the rocks, is the most numerous.   Whimbrel, with the down-turned beak and stripes across its eyes and head, shares space with Marbled Godwit, with the beak pointing skyward and streaked with brown and gold feathers.

Some of these shorebirds can also be seen feeding at Del Rey Lagoon in Playa del Rey and in Ballona Lagoon on the Marina Peninsula – now two lagoons in different communities of humans, but connected easily by short flights and once part of the more than three mile long historical Ballona Lagoon.

These distinctive birds I once was sure all looked too much alike to identify are worthy of my attention.  Now I know them better, and they not only provide a constant source of wonder, but they signal summer is on the wane and autumn will be arriving soon.

© 2011, Marcia Hanscom & Ballona Institute

Marcia Hanscom is a writer, a community organizer and an environmental activist.  She is Co-Director of Ballona Institute and Director of the Wetlands Defense Fund ~ projects of the International Humanities Center