Geology ReportsSearch

Geology topics

B. Young

Publications and source records attributed to B. Young.

3 recordsLinked to original sources

Documentation of a Gulf sturgeon spawning site on the Yellow River, Alabama, USA

The Gulf Sturgeon Recovery Plan (USFWS, GSMFC and NMFS 1995) stressed the need to provide maximum protection to Gulf sturgeon spawning habitat. The approach employed by various Gulf sturgeon researchers, including ourselves, to document spawning has been to identify potential spawning habitat on the basis of physical characteristics and/or tracking data, collect eggs, and then raise the eggs in the laboratory until the point where the larval fish can be identified (e.g., Marchant and Shutters 1996, Sulak and Clugston 1998, 1999). However, collecting eggs in any appreciable number is usually difficult, and these eggs may not always be viable upon return to the laboratory. Molecular methods provide an alternative means of identifying the species represented by an egg. Notable examples related to sturgeon conservation include cases where molecular markers were used to verify the sources of commercially available caviar (DeSalle and Birstein 1996, Birstein et al. 1999). Parauka and Giorgianni (2002) reported that potential Gulf sturgeon spawning habitat is present in the Yellow River; however, efforts to document spawning by the collection of eggs or larvae have been unsuccessful in the past. Herein, we report on the first successful collection of eggs from a potential spawning site on the Yellow River and the verification of their identity as Gulf sturgeon by using molecular methods.

Alabama, Florida

Fishes of the Missouri national recreational river, South Dakota and Nebraska

Two sections of the Missouri River, one extending 94 km downstream from Gavins Point Dam, and the other extending 62 km downstream from Fort Randall Dam, are legally designated as National Recreational Rivers. An ichthyofaunal list and fish habitat data were needed for conservation planning by states and federal agencies (e.g., National Park Service). We collected fish during three summers from four macrohabitats, using five fish collection techniques, and measured fish habitat characteristics. Temperature, conductivity, and turbidity varied little, but substrate, depth, and velocity differed among macrohabitats (e.g., depth and velocity in the channel exceeded those elsewhere; sand dominated the substrate except in silt-laden tributary mouths and backwaters). We collected 21,699 fish of 53 species and combined our survey with others to compile a list of 92 species. Common recreational species included walleye (Sander vitreum) and catfishes (Ictaluridae). Twenty nonnative species were present. Seventy-two native species have persisted, but the pallid sturgeon (Scaphirhynchus albus) is endangered and a few other species (e.g., native minnows) may be in decline.

Great Plains Research