Wellfleet Bay Natural History Notes

Eastern Bluebird

Mass Audubon's Ashumet Holly Wildlife Sanctuary in East Falmouth near Rt. 151 is well known for its 65 varieties of holly trees planted throughout the sanctuary and rare wildflowers that bloom in late summer. You’ll find a flurry of activity near the small barn in August with resident barn swallows and colorful bluebirds. The Eastern Bluebirds can be found around the many nest boxes on the western side of the sanctuary.  Bluebirds are known for singing a melodious series of soft whistled notes.

The bluebird is a very popular and beloved sight on Cape Cod.  This brightly colored bird with its vibrant blue and chestnut colored body is most frequently seen in open woodlands, meadows, and grassy fields.  They often make their nests in man-made nesting boxes and natural tree cavities.  A hundred years ago when the Cape was covered with farm fields, bluebirds had plenty of habitat, but those meadows were erased with the return of forests.  Thanks to many local efforts, bluebirds are returning to Cape Cod with a growing number of bluebird trails with a series of nest boxes mounted on fence posts.

The Cape Cod Bird Club (CCBC) has volunteers that monitor eastern bluebird nestbox trails in four locations on the Cape. Their monitoring does help the bluebirds and other native cavity-nesting species succeed.  CCBC monitors nestbox trails at Crowes Pasture in East Dennis (14 boxes), and at Thompson’s Field (24 boxes), Bank Street Bogs (44 boxes) and Texeira Field (8 boxes) in Harwich, amounting to more than 80 boxes in total!  All sites are also being surveyed for bird and other animal species, as well as plants.  The Harwich Conservation Trust and CCBC have combined to create a bluebird trail in Harwich at the Bank Street Bogs which features 44 nest boxes on 60 acres of conservation land just south of Route 39. 

Enjoy,

Craig Gibson
Woods Hole

Saltmarsh Sparrow

For most birders, the task of identifying Sparrows is daunting and challenging!  However, only a small handful of sparrows are typically found in grassy marshes.  The Saltmarsh Sharp-tailed Sparrow is a common summer breeding bird in Massachusetts.  This sparrow is mostly found in coastal salt marsh habitats.  The images below are from a recent trip to South Beach in Chatham.  Saltmarsh Sparrows are known to be quite secretive as they forage in the marsh for food.  Their song is made up of a series of sweet, soft gurgling notes.

According to The Sibley Field Guide for Eastern North America, the Saltmarsh (Sharp-tailed) Sparrow is “a rather long-billed sparrow with a bright orange triangle on its face, usually distinct dark streaks on its breast, relatively dark gray-brown back with white stripes, and gray crown.”  The Mass Audubon Breeding Bird Atlas mentions that “most migrant Saltmarsh Sharp-tailed Sparrows arrive during the last week in May. Nesting starts almost immediately in the wide, flat swales of the soft green Salt-hay.  They tend to form loose colonies with little or no courtship behavior prior to nesting. The nests are neat, cup-shaped structures placed on the ground or tucked under tufts of grass.”

This sparrow is a "species of conservation concern" for the U. S. Fish and Wildlife Service as well for a number of coastal states.  The Saltmarsh Sparrow's limited range and shrinking habitat concern conservationists. A National Audubon report states that “on top of habitat losses caused by commercial development, the Saltmarsh Sharp-tailed Sparrow is impacted by toxic environments and the invasion of exotic plant species.  Extensive, healthy marshlands dominated by grasses are essential for the Saltmarsh Sparrow.  The Mass. Audubon online Cape Cod Weekly Bird Sightings recently reported 11 horned larks, 300 tree swallows, and 18 saltmarsh sparrows at South Beach in Chatham.

Enjoy,

Craig Gibson
Woods Hole