The Delmarva Peninsula separates the Atlantic Ocean and the Chesapeake Bay. The last 100km of the peninsula form a narrow land mass averaging 10 km in width. The Lower Delmarva IBA comprises the southwestern tip of the peninsula along the bayside. The landscape is highly disected and dominated by agricultural fields. Forest tracts are generally small and isolated with mixed vegetation. The exceptions to this pattern are the forested corridors along the bayside and seaside margins.

{link:For a fact sheet on this IBA, including a map, click here|}

Ornithological Summary

The lower Delmarva supports a spectacular fall migration of southbound land birds. Due to the long narrow shape of the lower peninsula and the resulting funneling effect, over 10 million neotropical and temperate migrating passerines and 20 to 80 thousand nocturnal and diurnal raptors are estimated to pass through the area each fall. Passerine migrants use the area as a stopover to rest and refuel, while the raptor species often stopover to prey on available small birds and mammals while migrating through. The landscape mosaic of agricultural lands and woodlots provide important habitat for breeding and wintering species as well. Fallow fields support large populations of Eastern Meadowlarks, Grasshopper Sparrows, Field Sparrows, and Northern Bobwhites. The maritime pine forests that line the peninsula and the Chesapeake Bay support some of the highest breeding densities of Chuck-Will's-Widows in their range and likely support large populations of Brown-headed Nuthatches. This area is also an important winter trap for the American Woodcock, with a high count of 570 reported during the Cape Charles Christmas Bird Count in 1993.

Conservation Issues

The single greatest threat to this area is the ongoing conversion of habitat to residential and commercial development. In the past decade, interest in the area from developers and potential homeowners has greatly increased, leading to an incredible rise in land valuations. Further increase may price the conservation community out of the market. Most of the privately owned land along the bayside has been subdivided for development for a period of 15 years or more. Much of the inland parcels have been subdivided in more recent years. Recent investments in residential developments suggest that the area is nearing a sea change in habitat loss. Other significant threats include the various factors (deer overpopulation, clearing for land sale or development, overstocked pine plantations that lead to canopy closure) that contribute to understory loss.


A modest percentage of the Lower Delmarva IBA is owned and protected to meet various conservation objectives, including providing habitat for migrants. Holders include the US Fish and Wildlife Service, The Nature Conservancy, and the Virginia Department of Conservation and Recreation, Division of Natural Heritage. Acquisition of parcels demonstrated to be important to migrants is a continuing goal of a consortium of land-based agencies and conservation organizations. The remainder of the site is privately owned.


Forest tracts are generally small and isolated with mixed vegetation, with the exception of the forested corridors along the bayside and seaside margins. Canopy trees are dominated by Loblolly pine, Virginia pine, red maple, and various oaks and hickories. Understory trees are dominated by flowering dogwood, black cherry, and american holly. A small percentage of the site exists in fallow pastureland. The majority of the site is actively farmed.

Land Use

Land use is primarily pastoral in nature. A significant portion of the site is actively farmed in row crops and pasture. Parcels that are important for migrants are aquired whenever possible and managed for conservation. A modest portion of the site is already managed for wildlife and conservation through various organizations/agencies.

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