Sublethal Effects of Three Ectoparasites on Fish
File(s)
Date
1973-11Author
Vaughan, Gene E.
Publisher
University of Wisconsin-Stevens Point
Metadata
Show full item recordAbstract
In an attempt to determine sublethal effects of parasites
on fish, vulnerability-to predation, resistance to high
temperature, weight-length relationships, and fecundity were
compared for fish with and without or with light and heavy
infestations of three ectoparasites. Species used were fathead
minnow (Pimephales promelas) with anchor worm (Lernaea
cyprinaceae) infestation levels ranging from 0 to 4 with a
mean of 1.2 parasites per fish, brook trout (Salvelinus
fontinalis) infested with gill lice (Salmincola edwardsii)
at levels of 0 to J2 lice per fish with a mean of 4.1, and
yellow perch (Perea flavescens) with black-spot (Neascus
of Crassiphiala bulboglossa) with a range of 0 to 6JJ cysts
per fish and a mean of 249. The only sublethal effect
found was that of gill lice, which reduced resistance of
brook trout to high temperature. None of the three actoparasites
increased vulnerability of fish to predation by
piscivorous fish. Weight-length relationships were the
same in natural populations of brook trout with and without
gill lice and in two groups of yellow perch, one with a
light and one with a heavy infestation of black-spot.
Fecundity of brook trout was not affected by gill lice.