Salmonid Redd Superimposition in the Feather River, CA: the Association Between Spawning Habitat Characteristics and Salmonid Species
Abstract
Chinook Salmon and Steelhead Trout are an essential part of the riverine and ocean ecosystem. Unfortunately, they are a species of concern with declining wild populations. This is partially caused by decreased spawning habitat due to anthropological disturbances, and potentially leading to redd superimposition. It is unknown whether Steelhead spawning habitat characteristics in the Feather River overlaps sufficiently with that of Chinook to make redd superimposition likely to occur. This study aims to fill that knowledge gap by studying the Steelhead trout and Chinook salmon populations’ redd characteristics in the Feather River, CA. Although we found large overlap in spawning habitat characteristics on the bivariate level implying superimposition is likely to occur, we concluded from multivariate analysis using logistic regression that this overlap is minimal of nature and not of management concern due to the abundance of different channel widths available in the Feather River. Understanding spawning timing, habitat characteristics, and the overlapping of spawning habitat can help researchers and land managers make sound decisions relating to habitat restoration and hatchery efforts to improve these salmonid populations - listed as threatened species under the Endangered Species Act - in managed river systems.