In Arizona, various nonnative trout have been stocked since the early 1900s, and trout angling remains an important component of the sportfishing industry. These nonnative rainbow trout may have contributed to the decline of Little Colorado spinedace. The overall purpose of the research was to define interactions so that impacts to both trout management and spinedace populations can be minimized. Our objectives covered 5 broad areas of potential interaction: habitat use, diet, predation, health, and distribution.

This project consisted of multiple activities: Fish salvage, fish holding and repatriation, stream renovation, fish barrier construction and watershed stock tank renovations. Fish salvage and restocking operations were done in coordination and in conjunction with USFWS and a larger research project being conducted by NAU through separate funding. Brief information on methods and results from those efforts are provided. The Department, utilizing resources provided directly by USBR and via a grant from the FWS, implemented holding facility construction and operation. The Department coordinated the stream renovation with planning and implementation assistance provided by all the aforementioned partners. The USBR conducted all activities related to the fish barrier design and construction, details of which will not be included in this report.