In Alberta, this species was found to be most abundant in floating cattail mats in marshes (Landry 1994). "Within flooded macrohabitats both
A. ferruginosum and
A. thoreyi predominantly occupied microsites with emergent substrate or clumps of dead vegetation. In one marsh where
A. ferruginosum co-occurred with
A. lutulentum, their macrohabitat distributions were mutually exclusive. " (Landy 1994).
Reference: Landry, Jean-Francoise. 1994. Resource Partitioning in a Guild of Marsh-dwelling Agonum (Coleoptera: Carabidae) in Central Alberta. The Canadian Entomologist 126 (3).