Publications

No abstract available.

No abstract available.

Submerged aquatic plant populations in the Susquehanna Flats of the Chesapeake Bay were followed for 18 years. An exotic species, eurasian water milfoil, Myriophyllum spicatum, increased dramatically from 1958 to 1962; at the same time the dominant native species declined. After 1962, milfoil populations declined and the native rooted aquatics gradually began to return to their former...

Eggs of barn owls (Tyto alba) were collected from 18 nests in offshore duck blinds on the Maryland side of the lower Potomac River estuary in 1972 and 1973 and analyzed for organochlorine residues. DDE was found in 100% of the clutches, PCBs in 89%, and dieldrin in 78%. Eggshell thickness was inversely correlated with concentrations of DDE, DDD, and dieldrin residues. Six of the 18...

No abstract available.

A procedure is outlined for estimating the depths of floods of specified exceedance probabilities for Maryland streams west of the Chesapeake Bay. Data required for use of the estimating procedure are the stream's location in one of three flood-depth regions and the drainage area. Regression equations developed for depth estimation of the 50-, 20-, 10-, 2-, and 1-percent floods have...

A pilot Breeding Bird Atlas was initiated during 1971 in Montgomery County. A second atlas was begun during 1973 in Howard County. The Montgomery project was completed in 1973 and the Howard project in 1975......A total of 138 species were recorded for the two counties (129 confirmed, 7 probable, 2 possible). Montgomery County had 135 species recorded (122 confirmed, 9 probable, 4...

Twelve of 43 pregnant little brown bats (Myotis lucifugus) collected at Montpelier Barn, Laurel, Maryland, gave birth to dead young. Eleven of these 12 dead neonates were abnormally small. Most of the stillbirths were attributable to unknown reproductive difficulties associated with first pregnancies, but four may have been due to high concentrations of polychlorinated biphenyls (PCB) in...

Heavy minerals in bottom-sediment samples of the lower Chesapeake Bay show distribution patterns and interrelationships that denote characteristic mineral suites associated with defined geographic provinces. The Baymouth province has a garnet-hornblende-pyroxene suite, which is largely attributed to the influx of littoral and shelf sediments; the Eastern Shore province has a similar...

No abstract available.

No abstract available.

Pollution of estuaries affects bird populations indirectly through changes in habitat and food supply. The multi-factor pollution of Chesapeake Bay has resulted in diminution of submerged aquatic plants and consequent change in food habits of the canvasback duck. Although dredge-spoil operations can improve wildlife habitat, they often result in its demise. Pollution of estuaries also...