North American Journal of Fisheries Management 28:516�522, 2008

Copyright by the American Fisheries Society 2008

Physiological and ecological differences among

FLMB, NLMB, and their hybrids have been documented.

For example, they exhibited different critical

and chronic thermal maxima (Fields et al. 1987) and

different mortality rates when held at low temperatures

(Carmichael et al. 1988). In addition, FLMB and

NLMB differ in the timing of spawning, growth rate,

reproductive success, and survival (Isely et al. 1987;

Gilliland and Whitaker 1991; Philipp and Whitt 1991).

Performance differs among endemic units within the

historic range of FLMB and NLMB. For example,

growth and survival differed between progeny of

parents from different drainages in Illinois (Philipp

and Claussen 1995). Similarly, swimming performance

differed between Illinois and Wisconsin populations of

bass (Cooke et al. 2001). Lastly, the survival, growth,

and reproductive success of the local stock were higher

than those of the nonlocal stock when comparing

performance among Wisconsin, Illinois, Texas, and

Florida populations at each locale (Philipp et al. 2002).