Publications

The American black duck, with its brownish-black plumage and iridescent violet speculum, is one of the wariest of all the large dabbling ducks (Kortright 1942; Fig. 1). The black duck’s distribution is confined to eastern North America but extends into Manitoba. The black duck breeds in a variety of habitat types, from the brackish coastal marshes of North Carolina to the open boreal...

Ecotourism management seeks to integrate and balance several potentially conflicting objectives: protection of natural and cultural resources, provision of recreation opportunities and generation of economic benefits. In the absence of effective planning and management, ecotourism can lead to significant negative impacts on vegetation, soil, water, wildlife, historic resources, cultures...

A comprehensive database of sediment chemistry and environmental parameters has been compiled for Boston Harbor and Massachusetts Bay. This work illustrates methodologies for rescuing and validating sediment data from heterogeneous historical sources. It greatly expands spatial and temporal data coverage of estuarine and coastal sediments. The database contains about 3500 samples...

Heavy metal and organic contaminants have been determined in undisturbed sediment cores from the US Environmental Protection Agency reference site for dredged material on the continental slope off San Francisco. As expected, the concentrations are significantly lower than toxic effects guidelines, but concentrations of PCBs, PAHs, Hg, Pb, and Clostridium perfringens (a bacterium spore...

We previously reported indirect but compelling evidence that fine-grained H2O ice under elevated CH4 gas pressure can persist to temperatures well above its ordinary melting point while slowly reacting to form methane clathrate hydrate. This phenomenon has now been visually verified by duplicating these experiments in an optical cell while observing the very slow hydrate-forming process...

The concentrations of metals in surface sediments of Boston Harbor have decreased during the period 1977–1993. This conclusion is supported by analysis of: (1) surface sediments collected at monitoring stations in the outer harbor between 1977 and 1993; (2) metal concentration profiles in sediment cores from depositional areas of the harbor; and (3) historical data from a contaminated...

Calculated annual excess skin friction stress at various locations in Quincy Bay (outer Boston Harbor) was found to be correlated positively with sediment sand content. The correlation was optimized when a critical shear stress (??c) of 0.085 Pa was assumed for the bay. The excess shear stress was correlated negatively with sediment lead (Pb) and polychlorinated biphenyl (PCB)...

The Toms Canyon structure [~20-22 km wide] is located on the New Jersey outer continental shelf beneath 80-100 m of water, and is buried by ~1 km of upper Eocene to Holocene sedimentary strata. The structure displays several characteristics typical of terrestrial impact craters (flat floor; upraised faulted rim: brecciated sedimentary fill), but several other characteristics are atypical...

Three-component (throughfall, soil water, groundwater) hydrograph separations at peak flow were performed on 10 storms over a 2-year period in a small forested catchment in north-central Maryland using an iterative and an exact solution. Seven pairs of tracers (deuterium and oxygen 18, deuterium and chloride, deuterium and sodium, deuterium and silica, chloride and silica, chloride and...

Fry of rainbow trout Oncorhynchus mykiss were exposed to serotype VR-299 of infectious pancreatic necrosis virus (IPNV) by using a standardized immersion challenge. In concurrent experiments, fish were monitored for 11 d for excretion of IPNV or monitored for 9 d for excretion and transmission of IPNV to susceptible rainbow trout fry. Immersion-challenged fish began excreting virus...

More than 10 inches of rain fell on some areas of eastern Massachusetts and more than 7 inches fell on some areas of Rhode Island during and intense and prolonged rainstorm from June 12 through June 15, 1998. On some streams, the magnitude of the floods resulting from the rain would be exceeded, on average, only once every 50 years. Estimated property damage from the June 1998 floods...

No abstract available.