head, mouth and barbels of juvenile dangerous invasive freshwater predator channel catfish, ictalurus punctatus attentively stares

aggressive america animal aquaculture aquarium aquatic attentively barbel barbels biotic biotope cat catfish channel clear close coldwater dangerous ecology ecosystem european fauna fish freshwater greedy grey head ictaluridae ictalurus instinct invasion invasive juvenile macro mouth natural nature popular portrait predator punctatus reservoir river sand stare stares states system tank threat underwater united voracious water widespread wild