The invasive cladoceran Cercopagis pengoi is a generalist predator capable of feeding on a variety of prey species of different sizes and escape abilities
Pichlová-Ptáčníková, Radka; Vanderploeg, Henry A.
published: Jan 1, 2009
ArtNo. ESP141017304001, Price: 29.00 €
We carried out a comprehensive exploration of predation by the invasive predatory cladoceran Cercopagis pengoi in the laboratory. A range of potential prey was offered to the predator, including all major summer nearshore zooplankton taxa in Lake Michigan; we used prey in different concentrations from 5 to 100 ind. L-1. We found that Cercopagis is a generalist capable to consume a variety of prey species, including small and large prey, and slowly and rapidly swimming prey. Consumption rates increased with concentration in several species, but did not saturate even at the highest concentration tested (40 or 100 ind. L-1). Cladocerans were consumed at a higher rate than copepods. Cercopagis was able to catch and handle prey of nearly its own body size to prey about seventeen times smaller; however, it did not show any clear size preference within this range. In contrast to most indigenous Great Lakes zooplankton, Cercopagis can efficiently feed on veligers of the zebra mussel, another invader from the Ponto-Caspian region.