Development and Evaluation of Habitat Suitability Criteria for Native Fishes and Assessment of the Relationship Among Riparian Areas and Stream Macrohabitats Type and Fish Presence in Four Central Arizona Streams

Abstract

Habitat loss is an important reason for fish fauna declines in the southwestern U.S. Several studies have defined habitat conditions for selected native fish species in Arizona, yet habitat use can vary across streams due to a variety of biological and physical factors. In addition, previous studies have focused on effects of instream habitat characteristics and less on how riparian areas structure aquatic communities of the Southwest. Riparian areas affect aquatic communities in a variety of ways, including structuring instream habitat. Macrohabitat (riffle, run, pool) is an important determinant of fish use, and little is known about the effect of riparian vegetation and associated land use activities on the formation of macrohabitat. Therefore, the objectives of my study were to 1) evaluate suitable habitat for native Arizona species, and 2) to investigate the relationships among riparian vegetation and stream macrohabitats type and fish presence in four central Arizona streams. Fish and habitat data were collected in four streams along the Mogollon Rim in Arizona during the 2017 summer field season at base flow conditions. I used the National Hydrography Dataset (NHD) and National Agricultural Imagery Program (NAIP) aerial imagery to estimate the amount of vegetation cover within the riparian areas of each stream. I developed habitat suitability criteria for four native species in three streams. Most generalized criteria did not transfer among study streams, similar to finding from past studies suggesting that stream-specific criteria were more accurate. I found that Smallmouth Bass and Red Shiner had a negative relationship to canopy cover, possibly explained by high temperature tolerances of both species. Desert Sucker and Speckled Dace presence were positively related to presence of riffle habitat, as has been noted in previous habitat studies. Riffle habitat was positively related to increases in riparian vegetation cover. These results can inform researchers, agencies and stakeholders who study and manage Arizona’s riparian areas and instream habitat.