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Pamela J. Schofield

Publications and source records attributed to Pamela J. Schofield.

41 records · Page 3Linked to original sources
USGS2007

Assessment and control of an invasive aquaculture species: An update on Nile tilapia ( Oreochromis niloticus ) in coastal Mississippi after Hurricane Katrina

We provide information about the effects of Hurricane Katrina on populations of an invasive fish, the Nile tilapia (Oreochromis niloticus) in southern Mississippi. By resampling areas surveyed before the storm, we attempted to determine whether the species expanded its range by moving with storm-related floods. Additionally, we used rotenone to eradicate individuals of this species at a hurricane-damaged aquaculture facility on the Mississippi coast. Although our survey was limited geographically, we did not find the species to occur beyond the aquaculture facility, other than in an adjacent bayou. Our rotenone treatment of the facility appeared effective with only a single O. niloticus being collected six weeks after the treatment. To reduce the spread of O. niloticus in the southeastern U.S., it is important to continue to control feral populations, work to eliminate vectors for dispersal, and continue monitoring their distribution.

Southeastern Fishes Council Proceedings↗
USGS2003

Habitat selection of the channel darter, Percina (Cottogaster) copelandi, a surrogate for the imperiled pearl darter, Percina aurora

Percina (Cottogaster) aurora is an imperiled species under consideration for listing by the U.S. Fish and Wildlife Service. To better understand habitat use of P. aurora , we studied a related and more abundant Cottogaster species, Percina copelandi , from the Ouachita River, Arkansas. We used a laboratory stream system to examine mesohabitat selection (pools versus riffles) and microhabitat selection (substratum particle size) of P. copelandi over three temperature regimes (summer, spring, and winter). Percina copelandi selected pool habitats over riffles and selected pools with coarse substrata ( e.g. , cobble) over fine substrata ( e.g. , gravel). In riffles, P. copelandi selected large substrata during winter and spring but did not show particle size selection during summer. These data, and various published and unpublished field data for P. aurora , suggest that habitat use of P. aurora is also centered around deep runs and pools, with large substrata likely being more important at low water temperatures.

Journal of Freshwater Ecology↗