James R. Jackson

The impacts of many species of piscivorous birds on aquaculture are well documented in the southeastern United States; however, specific studies of black-crowned night heron (Nycticorax nycticorax) in these areas are lacking. Because black-crowned night herons opportunistically exploit abundant food resources and inhabit an important catfish production area, we initiated a study to assess their use of and potential impacts on a catfish aquaculture facility. We conducted a biweekly survey October 2004-September 2006 on Harvest Select Farms near Inverness, Mississippi, to quantify year-...

The availability of quality nursery habitats can be an important factor in the recuitment dynamics of littoral fish species. Eight artificial habitats composed of crushed rock substrate were established in littoral areas of an embayment of B. E. Jordan Lake, North Carolina, that historically exhibited low abundances of juvenile largemouth bass (Micropterus salmoides). Response of juvenile largemouth bass to habitats was assessed by night shoreline electrofishing at treatment sites and associated controls on 4 occasions during the growing season in each of 3 years. Significantly more age-0...

From 1987 to 1998, gill netting was conducted annually in Jordan Lake, North Carolina, usually 3 times per year with 9 nets distributed over 3 reservoir sub-basins. White perch (Morone americana) began appearing in gill-net samples in 1988. By 1993 they were the second-most abundant species (11.2/net night), following black crappie (Pomoxis nigromaculatus) (21.2/net night). White perch catch rates in 1994 (16. I/net night) exceeded rates for other fish captured in gill nets. White perch continued to constitute a large percentage (21.1%) of the gill-net catch from 1995-1998. Analysis of...

A total winterkill of threadfin shad (Dorosoma petenense) in B. Everett Jordan Lake, North Carolina, facilitated assessment of their role in the growth and condition of black crappie (Pomoxis nigromaculatus). Reductions in size at age and Wr were observed in Age 3 and older crappie in the year of the winterkill. Reestablishment of threadfin shad in the following year led to improvements in crappie population parameters, and within 2 years of the shad winterkill, crappie growth and condition had returned to pre-kill levels. The presence of a strong gizzard shad (D. cepedianum) year class...

The ability of shad populations to impact the density and composition of zooplankton populations has led to the suggestion that planktivorous shad may compete with young-of-year bass for plankton food resources and influence bass recruitment. We studied the feeding dynamics of concurrent year classes of threadfin shad (Dorosoma petenense) , gizzard shad (D. cepedianum) , and largemouth bass (Micropterus salmoides) in a North Carolina reservoir to determine the nature of feeding interactions among the species. Shad planktivory was found to be confined to a brief period early in the growing...