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Research about Delaware, Maryland

Source-linked reports with geographic coverage including Delaware, Maryland.

At least 37 records · Page 2Linked to original sources
USGS1993

Avian communities in riparian forests of different widths in Maryland and Delaware

In agricultural landscapes, much of the remaining forest is in linear tracts along streams. These riparian forests provide habitat for forest birds, but their use by forest interior birds may depend on forest width. We conducted point-count surveys of birds in riparian forests on the Eastern shore of Maryland and Delaware to assess whether the presence of any species was dependent on corridor width. We surveyed 117 corridors that ranged from 25- to 800-m wide. Several area-sensitive neotropical migrants were encountered more frequently in wider riparian forests, and probabilities of occurrence increased most rapidly between 25 and 100 m. Based on these surveys, we recommend that riparian forests be at least 100-m wide to provide some nesting habitat for area-sensitive species. Wider riparian forests would be preferable and should be preserved.

Delaware, Maryland↗
USGS1987

Survival of striped bass larvae and yearlings in relation to contaminants and water quality in the upper Chesapeake Bay

This study was designed to evaluate survival of striped bass yolk-sac larvae and yearlings at three locations in their natural spawning habitat in the upper Chesapeake Bay (Chesapeake and Delaware Canal) using “in-situ” chambers; correlate larval and yearling survival with the presence of 11 water quality parameters, 10 inorganic contaminants and 21 organic contaminants and assess histological effects on yearlings after exposure to habitat water. The cumulative percent survival ranged from 42–59.5% for striped bass larvae after 96 hr of exposure to habitat water during two experiments. Survival in control conditions during these two experiments was 77.5 and 80.5%. Data from previous studies have shown that mortality rates for wild yolk-sac larvae ranged from 7–19% per day. Daily mortality of larvae in the present study was 13–16%; therefore, suspected acutely harmful water quality or contaminant conditions affecting survival were not substantiated. All yearling striped bass survived 10 days of exposure to habitat water. Although habitat water was not acutely toxic, histological examination of surviving yearling striped bass indicated sublethal effects. Telangiectases (lamellar dilations) of the gills was reported for yearlings exposed to habitat water. This pathological change was not found in the controls.

Delaware, Maryland↗