exploring the effect of predator experience on yellow perch (perca flavescens) behaviour and predator recognition
abstract
recreational and commercial fisheries are important resources that can be
vulnerable to disruption by invasive species, particularly the introduction of top predators
into water systems that have not previously supported them. how prey fish species assess
and respond to predation significantly influences their vulnerability to this disruption. in
this experiment, 12 groups of 8 yellow perch (perca flavescens) from four lakes with
different exposures to piscivorous predators were placed into enclosures to observe and
record their behaviour around a food source and use of their environment, as well as how
the presence of a predator within the enclosure might affect this behaviour. in the first
trial, perch started in the half of the enclosure opposite a food source and upon removal
of a central barrier, were allowed access to a suspended porous container filled with food.
after this a second trial was conducted but with a northern pike (esox lucius) present in
the half of the enclosure with food to determine how the perch behavior changed from the
first trial. in response to the presence of a predator, predator-experienced yellow perch
consistently and significantly increased schooling and cover use while decreasing
foraging behaviour at the food source while in contrast, predator-naive yellow perch did
not significantly alter their behaviour. these trends in behaviour were consistent across
two rounds of sampling (summer and fall). this study demonstrates that previous
predator experience significantly affects yellow perch foraging and exploration
behaviour in the presence of a predator, highlighting that populations without previous
predator experience might be more susceptible to the detrimental effects of invasion by
top predators.