Document: JEF-3-73-4

Modeling restoration of Michigan tributaries and its effect on salmonid populations.

TYLER, J.A.* ¹ and E.S.RUTHERFORD ²

Worcester Polytechnic Institute, Worcester, MA 01609 USA ¹
University of Michigan, Ann Arbor, MI 48109 USA ²

Abstract:
Damming of Great Lakes tributaries has fragmented spawning and nursery habitats for anadromous fishes and fundamentally altered the physical and chemical properties of these important aquatic environments. Changes in river morphology, flow, substrate and water temperature imposed by dams may reduce the reproductive potential of salmonids and lower parr growth and survival. Dams impede fish migration to suitable spawning grounds, reduce the quantity of suitable spawning habitat, and degrade productive nursery areas for parr growth and survival. Remarkably little attention has been paid to evaluating the effects that dams and their management have on salmonid populations. Here, we present a spatially-explicit, individual-based model (IBM) of salmonids in tributaries to Lake Michigan. The model simulates the period from adult spawning through the smolt stage. Simulated parr forage and grow according to well accepted models and select habitat using fitness based rules. Adult spawning and parr survival follow size-based rules derived from data. The spatially-explicit tributary environment allows simulations to explore the effect of environmental change on the salmonid population. Simulation results show that changes in water temperature and substrate affect salmonid population abundance and distribution and that their effects interact with salmonid density.

Keywords: salmonid, tributaries, restoration

This abstract is being presented at: 1:00 PM in session:
Oral Session #46: Modeling Populations and Statistical Ecology.