2009

August 12, 2009
It’s a warm summer’s evening in mid-August of 2008 and dusk is drawing its veil over the Maurice River.  The wind is dying down too.  A certain hush blankets the marshes.  And then as if someone has hollered, “Lights out!” it begins.  From seemingly all directions the sky is dotted as if sprinkled with pepper. Then the forms get larger and we can make out flocks of purple martins descending on us from all directions.  They’re coming to the shores of the Maurice River to bed down for the night. 

Just north of the Mauricetown Causeway Bridge is a regional staging ground for migrating purple martins. Clouds and swirls ebb and flow in the air like an airborne school of fish.  The martins land among the reeds.  Their voices are all raised with the excitement caused by each newly arriving wave of winged torpedoes, hurling about at average speeds of 17-27 miles an hour and up to 45 mph. At times settling in seems a difficult task, and it appears that previous arrivals take to flight once again.  The commotion makes my head spin in an endless attempt to try and catch each newly arriving wave of birds.  At one point my kayak tilts; in my unbridled enthusiasm I nearly forget that balance is an important issue. Whew, that was close!  A whoosh from the birds’ wings momentarily overpowers other noises and my camera’s shutter sounds briefly like a fashion model’s photo shoot.  In an effort to steal the show, red-winged black birds let out their distinct call - a shrill buzz followed by a conk-a-reeee.

Paddling a short distance into the maze of tall phragmites for a closer look, we see the flocks traverse the tops of these reeds and dip lower when they cross the labyrinth carved by the channels. Their speed and accuracy is amazing.

I ponder the benefits of flying in flocks.  There are so many watchful eyes scanning for dangers.  A prospective predator might think twice about diving into a sea of prey for fear of being injured in a collision.  How difficult it must be to focus on a single target when so many are amassed.  I try to track just one bird among the flock, but it’s simply impossible.  One out of formation might be captured.  It seems with so many hungry beaks the bugs don’t stand a chance in this mob.

To a limited extent birds experience energy gains by flying in a flock. Each bird’s propulsion forward causes a vortex, a change in air-flow, that its neighbor benefits from, much like racing cyclists who take turns leading a team. Evidently, larger birds get greater benefit in this department than martin-sized birds.  One can’t help but marvel at their uniform spacing, as they navigate the air above the marsh, holding a direction and velocity in a marvelous display of coordinated aerobatics. In my limited research it appears this coordination remains one of nature’s great mysteries, not that it is without theories.

I feel as though I am at a great airport where multitudes of birds are piling into a gate to make the big trip south to Brazil. Thousands keep arriving from presumed local environs where they fuel up on insects to build the fat resources necessary for departure.  And then the greatest marvel of all strikes me - each of these birds lives in housing provided by landlords – yes, structures built by people. Martins are secondary cavity nesters, meaning they nest in natural cavities but don’t actually build them. Over time the purple martins in the eastern half of the United States have become entirely reliant on people for housing.  Supposedly Native Americans provided hollowed-out gourds for nesting martins so that the birds would warn them of intruders by making their typical martin ruckus upon spotting something unusual.  The relationship has continued to this day. So as these vast numbers assemble I think of the countless people who are providing for their housing. I smile with ambivalence – how wonderful and kind of people, but yet I feel a tinge of sorrow that the birds are not more fiercely independent.

As I watch from my kayak, night falls with a quieted hush, a full moon’s refection sparkles on the water, and the commotion of the past half hour is extinguished like a bedside candle.  The spectacle is over for another day.

Where and when do purple martins stage? At the Mauricetown Bridge, Route 670 (just west of Route 47 Wawa) Dorchester, Maurice River Township in mid-August.

If you want the benefit of camaraderie, this year’s annual Purple Martin Migration Spectacular is Friday and Saturday, August 14 & 15.  Bring your binoculars and bug repellent. Hosted by Maurice River  Township with help from Citizens United to Protect the Maurice River and Its Tributaries, Inc. the Cape May Bird Observatory and the Natural Lands Trust, the event includes evening boat cruises and kayak trips to afford great views of this imposing migration phenomenon. For more information and to make reservations for the cruise, contact Linda Costello at 856 785 1120 x 110.

Citizens United to Protect the Maurice River and Its Tributaries, Inc.’s own Allen Jackson mentors prospective landlords on the proper techniques for maintaining a healthy colony of birds.  In fact he is so talented in his advice that for the past few years he has banded over 8,000 chicks.

Contact us by email for more details: forrivers@comcast.net

How to become a purple martin landlord?
It helps if you live on or adjacent to a large field.
Read up on purple martins and then visit: http://purplemartin.org/ for local help. We will put you in touch with a purple martin mentor.

CU on the River!