Al. Sheldon et Gk. Meffe, SHORT-TERM RECOLONIZATION BY FISHES OF EXPERIMENTALLY DEFAUNATED POOLS OF A COASTAL-PLAIN STREAM, Copeia, (4), 1995, pp. 828-837
Fishes were removed from pools in a South Carolina stream to observe s
ubsequent recolonization patterns and development of community structu
re. Recolonization, measured between two and 32 days, was rapid; and d
ownstream sites attained preexperimental density, richness, and propor
tional composition by day 32. However, recovery of upstream sites was
incomplete in that time. Species colonized in proportion to abundance,
and rare species returned later; both of these results are interprete
d as simple proportional sampling of a mobile fauna. In a longer exper
iment, defaunated pools did not differ from controls; and density, ric
hness, and composition showed no temporal trend over 31-63 days. Movem
ent, measured by directional trapping, was dominated by spawning yello
wfin shiners (Notropis lutipinnis), but 16 of 26 species present were
trapped, demonstrating active movement by much of the fauna. Rapid rec
olonization of defaunated areas is plausibly explained by a combinatio
n of high mobility and equilibrium with source populations.