A landscape-based distribution model for fallfish (Semotilus corporalis) in the Great Lakes drainage of New York

Abstract

Fallfish (Semotilus corporalis) is a large native minnow that can be both an important food source and a predator on juvenile stream fishes, including salmonids. We developed a fallfish abundance-habitat neural network model. The model explained a large fraction of observed fallfish abundance class variation (R2=0.91) and predicted optimal habitat in relatively flat, low elevation, cool to warm streams associated with forested landscapes. The distribution of optimal habitat areas was limited to 9% of the stream network, but one concentration overlapped with the best salmonid production habitat in the Lake Ontario basin. These model results can help managers better understand fallfish distribution and habitat requirements, as well as help them better assess potential interspecific interactions with gamefish in the Lake Ontario–St. Lawrence drainage.