Cooperative Fish and Wildlife Research Units Program: Arizona
Education, Research and Technical Assistance for Managing Our Natural Resources

Arizona Project

Habitat Suitability Criteria for Northern Crayfish

August 2011 - December 2017


Participating Agencies

  • USGS/USFWS Science Support Program

A concern with the survival and persistence of native species is the introduction of non-native species. In the Southwest, especially in Arizona, a growing concern is the introduction of the non-native virile or northern crayfish Orconectes virilis. Virile crayfish not only negatively affect native threatened and endangered fish populations but also other vertebrates (Sonoran mud turtles Kinosternon sonoriense, leopard frogs, Rana chiricahuensis, and narrow-headed garter snake Thamnophi rufipunctatus), macroinvertebrates, and aquatic plants. Effective or efficient control methodologies for crayfish have proven elusive; however, reducing the amount of habitat for crayfish might give promise. Thus, determining which habitat parameters are optimal for crayfish and more importantly, which parameters are unsuitable for crayfish is critical. We are developing habitat suitability criteria for northern crayfish then identifying and assessing overlap in habitat criteria for other managed aquatic species (Apache trout, Oncorhynchus giliae apache, brown trout Salmo trutta, or rainbow trout, O. mykiss) that may give habitat advantages to desired species. We sampled crayfish in the West Fork of the Black River every 5 meters moving upstream using a quadrat sampler. This enabled us to determine occupied and unoccupied locations and measure habitat parameters of each location. Apache Trout occupied areas with colder water and more instream and overhead cover than Virile Crayfish. My findings suggest that, to suppress Virile Crayfish populations and increase Apache Trout populations, managers must: (1) reduce stream warming, (2) increase water velocity, (3) trap crayfish after floods, and (4) provide instream cover for Apache Trout. Understanding life history characteristics and habitat preferences of each species is critical to the management of species assemblages. This work was provided in a thesis and is now being formatted for journal publication. Partners include the USFWS.

Theses and Dissertations Publication Date
Petre, S. J. 2014. Habitat suitability criteria for Apache trout Oncorhynchus gilae apache and virile crayfish Orconectes virilis. MS. Thesis, University of Arizona, May 2014