Jan writes:
Separating abiotic from biotic causes is always tough. Agriculturally
impacted landscapes often have introduced populations of centrarchids, so
distinguishing effects of degraded habitat from predation is not easy.
Matthew Winston's study, however, is the first one I've seen that uses such
an extensive database (three statewide surveys during the periods 1938-1948,
1960-1968, and 1992 to 1998) and a rigorous screening technique to make all
survey data comparable.
By the way, Jay Hatch maintains an online Topeka shiner bibliography:
http://www.gen.umn.edu/faculty_staff/hatch/topeka/biblio.html
Recently, I have been thinking about my own Topeka shiners which are
retirees from some lab work we did - in summer 1998. Assuming they were
only 1 year old when we got them, the fish are now 5 years old. They are
believed to live only three years in nature.
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