A Multi-Sampling Approach to
Assess Striped bass Morone saxatilis Populations and Potential Thermal Refugia in a
Pascagoula River Tributary, Black Creek , Mississippi
Sherry L. Harrel, and Eric D. Dibble, Mississippi State
University, Department of Wildlife and Fisheries, Box 9690, Mississippi State, Mississippi
3976; Voice 601-325-2073 or 325-7494; FAX 601- 325- 8726
Keywords: striped bass; Morone saxatilis;
life stages; anadromous; thermal refugia
Striped bass Morone saxatilis populations have
declined in coastal river systems of the Gulf of Mexico. Timing and location of striped
bass spawning is correlated with temperature (19-24oC), flow, and salinity
(< 9ppt). After spawning, striped bass may remain in fresh water, seeking cool water
refugia (<27oC) with sufficient dissolved oxygen. The location,
characterization, and protection of critical spawning habitat, nursery grounds, and summer
refugia for striped bass in coastal river ecosystems are essential to the recovery and
management of this anadromous species. Investigations into potential spawning and thermal
refuge habitat have been ongoing in the Pascagoula River and its tributaries. Adult bass
have been previously captured in Black Creek, a tributary of the Pascagoula River located
in Southeast Mississippi. Few data are available on the status of striped bass populations
in Black Creek. Our objectives were to investigate availability of habitat in Black Creek
and use multi-sampling methods such as beach seines, gill nets, drift nets, and hand
seines to target adults, juveniles, larvae and pre-larvae. These samples were conducted at
55 sites along a 30-35 mi reach during May 1998 - October1998. Potential summer refugia
was identified in late spring and summer (May-July) with temperatures ranging from 24-31.5
oC. Our sampling efforts yielded 50 species of fish, however, no striped bass were
sampled. We present spatial and temporal relationships of the fishes collected to
physicochemical variables along the stream continuum. We conclude that there is available
habitat in Black Creek that may provide potential spawning sites and seasonal refugia for
striped bass, yet the numbers of striped bass using this tributary appear to be low.
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