This report summarizes monitoring activities conducted by Marsh & Associates, LLC (M&A) during calendar year 2019 for the Gila River Basin Native Fish Monitoring project (GRBMP). The primary objective of the current monitoring program is to detect the presence of each focal species in each stream and determine the distributional extent within occupied streams. Secondarily, evaluate fish community structure to determine the relative abundance of the focal species relative to co-occurring fishes. Here, detailed trip summaries with catch data are reported, results are summarized across sub-basins, species distribution maps were constructed, sampling gears were qualitatively evaluated, and a preliminary multivariate analysis of fish community composition was used to reveal complex patterns and relationships.
Surveys were conducted in selected streams of major drainages throughout the Gila River basin (Figure 1) that were not being surveyed by others (e.g., agencies, institutions, and private contractors). The focal species in each stream is one or more of five native species currently listed as threatened or endangered: Gila Chub Gila intermedia, Spikedace Meda fulgida, Loach Minnow Tiaroga cobitis, and Gila Topminnow Poeciliopsis occidentalis, plus imperiled Roundtail Chub Gila robusta.