ResFish v1.0 user manual

ResFish v1.0 is a program written in Java for planning the repair and removal of artificial in-stream barriers, which impair regular seasonal movements of resident fish species and other freshwater aquatic biota. The program uses a state-of-the-art heuristic solution algorithm (described below) to select barriers for repair or removal in order to maximize the connectivity of stream reaches within a watershed, subject to a limited budget on the total cost of barrier removal and repair actions.

More specifically, the program maximizes overall connectivity weighted habitat based on the Cind connectivity metric (Deibel et al. 2009), which accounts for the amount (length), quality and distance of different habitat types (e.g., stream orders) that can be accessed by stream-resident fish from any given focal stream segment by successfully traversing upstream/downstream and back again through any intervening artificial or natural barriers. More specific details on the structure and formulation of the ResFish decision problem are given the Appendix below.

Access to a range of different habitat (steam orders) types is important not only as part of the normal life-cycle of resident fish (e.g., movement from spring spawning areas in low order headwaters to summer feeding grounds in mid-order streams to over-wintering areas in deep water pools) but also provides access to refugia during large disturbances, such as floods and droughts, and has been shown to be an important determinant of stream-level species richness (Deibel et al. 2009).

The primary output of ResFish consists of an optimal to near optimal list of barrier removal/repair actions, the corresponding level of habitat connectivity and the total cost of barrier repair and removal.