Tuesday, May 20, 2008

Three Sparrows and the Lynnhaven Estuary.

As the 2008 spring season begins to wind down, one thing has become apparent. Three, rare and declining sparrows rely on the Lynnhaven estuary as a migratory stopover haven. On April 8th two new nets were established in the small, protected salt marsh along the tidal creek leading to White Lake upstream of the footbridge. On May 2d two more nets were set in the marsh along the opposite side of the tidal creek. These nets were placed in the marsh as far as possible away from the shrubs and trees of the uplands.

The nets immediately began to capture a number of migrating Marsh Wrens, 23 to date. Thereafter, Saltmarsh Sharp-tailed Sparrow, Seaside Sparrow and (pictured above) Nelson's Sharp-tailed Sparrow have been banded, 16 in total so far. Five Nelson's found the nets in the last week and they were each very fresh and bright having just completed their unusual spring molt. Today the marsh was quiet, but more will likely arrive before the season is over. This spring's captures, together with salt marsh sparrow observations of last fall, have led me to believe that the Lynnhaven estuary is an important link in the migratory route of the these three sparrows along the Atlantic coast.

Outside of First Landing State Park the coastal wetlands of the Lynnhaven estuary are widely disturbed and fragmented. And there are many pending applications and plans to alter and fill more wetlands within the estuary. Many find a need to alter the estuary's landscape to fit their requirements.

The Nelson's and other wetland birds are also facing another insidious threat to their existence-methyl mercury contamination. To read about this issue, go to: http://www.briloon.org/science-and-conservation/centers/mercury-toxin.php

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