Publications

No abstract available.

Hybridization has been used in aquaculture to produce fish that exhibit improved growth and survival over parent species. Previous studies produced an intergeneric hybrid by crossing female black drum Pogonias cromis with male red drum Sciaenops ocellatus. In the present study, the two parent species and their hybrid were simultaneously cultured in ponds for 9 mo. Two- to three-day-old...

No abstract available.

Lake Ontario marine seismic data reveal major Grenville crustal subdivisions beneath central and southern Lake Ontario separated by interpreted shear zones that extend to the lower crust. A shear zone bounded transition between the Elzevir and Frontenac terranes exposed north of Lake Ontario is linked to a seismically defined shear zone beneath central Lake Ontario by prominent...

A new plasticine-filled leg band was developed for use in banding dayold ducklings. These bands permit inference about early survival that is not possible from banding of older young in standard operations. Two double-marking experiments with web tags and the new leg bands indicated a high retention rate for the leg bands. In contrast, several web tags were lost, permitting an analysis...

A new, state-of-the-art method for mapping historical shorelines from maps and aerial photographs, the Digital Shoreline Mapping System (DSMS), has been developed. The DSMS is a freely available, public domain software package that meets the cartographic and photogrammetric requirements of precise coastal mapping, and provides a means to quantify and analyze different sources of error in...

The limnology of Lake Michigan has changed dramatically since the late Pleistocene in response to the expansion and contraction of continental glaciers, to differential isostatic rebound, and to climate change. The lake sediment's stratigraphic trends, magnetic susceptibility, δ18O, and ostracode species abundance ratios provide criteria to identify the lake's response to glacial ice and...

No abstract available.

A map showing ground-water levels in the carbonate rocks of northern Chester County, Pa., was constructed on the basis of water levels in 51 wells measured in May and June 1993. The area studied underlies parts of East Whiteland and Charlestown Townships. Water-level altitudes range from about 413 feet above sea level on Phoenixville Pike to 130 feet above sea level along Route 29.

The flow-routing module of the Hydrologic Simulation Program-Fortran watershed model was calibrated for 31 reaches on the Delaware River and 5 of it principal tributaries. These calibrations primarily involved the development of discharge-storage volume relations for the defined reaches. Daily discharge records for stream-gaging stations located at the upstream ends of the study reaches...

No abstract available.

Whole body and liver analyses indicated that wintering redheads (Aythya americana; n = 70) in coastal Louisiana (one site) and Texas (two sites) were relatively free of contamination with common trace elements, organochlorines, and hydrocarbons. Most trace elements, including As, Cr, Hg, Mg, Mn, Ni, Pb, Se, Sr, and Zn, were within background concentrations in livers; levels of B, Cd, Cu...