Assessing the Distribution and Environmental Associations of Burrowing Crayfish in a Restored Missouri Prairie

Author: Catlin Ames

Institution and/or Affiliation: University of Missouri 

Abstract:

Crayfish are the third most imperiled floral or faunal group in North America following mussels and snails (NatureServ 2012), and are proportionately the most imperiled faunal group in
Missouri, with 56% (20) of 36 species listed as species of conservation concern (Missouri Natural Heritage Program 2013). Information on the ecology and conservation of crayfish
species is lacking, with published research on crayfish life histories accounting for only 12% of 347 United States (U.S.) and Canadian species, and the majority of these focusing only on stream dwelling species (Welch and Eversole 2006, Taylor et al. 2007, Loughman 2010, Moore et al. 2013). The sparse ecological work that has been conducted on burrowing crayfish species indicates that they and their burrows provide several ecosystem services including soil mixing, respiration, nutrient cycling, and refugia for a suite of animals such as snakes, frogs, salamanders, non-crayfish crustaceans, nematodes, arachnids, mammals, and insects (Creaser 1931, Carpenter 1953, Williams et al. 1974, Richardson 1983, Norrocky 1991, Stone 1993, Pintor and Soluk 2006, Welch et al. 2008, Loughman 2010). The fossorial nature of burrowing crayfish species has limited the amount of research
conducted, resulting in life history or habitat information on only a small proportion of these species, even though burrowing crayfish account for 32% of all imperiled crayfish species
(Schuster 1976, Hamr and Sinclair 1985, Correia and Ferreira 1995, Johnston and Figiel 1997, Welch and Eversole 2006, Welch et al. 2008, Loughman 2010, Taylor et al. 2011, Helms et al. 2013a, 2013b). Burrowing crayfishes are particularly vulnerable to land-use disturbance and can have very limited distributions, in the case of one species, only a few acres (Helms et al. 2013b). In Missouri, prairie landscapes were once a dominate habitat (approximately 27% of the state), and species adapted to these environments after the retreat of glaciation (Schroeder 1981). Of these species, are a diverse array of the genus Orconectes sp., and a few known burrowing crayfish. One species in particular, Procambarus gracilis (grassland crayfish) is only associated with grasslands and prairies (Pflieger 1996). Prairie landscapes are now in great decline in the state, mostly by effect of agriculture (grazing, cultivation), and information on the use and distribution of crayfish in remnant or restored prairies are lacking (Schoeder 1981). A survey of the burrowing crayfishes on regional and local scales explicates on the biodiversity of the area, and often provides baseline data on their distribution. Further, understanding the environmental associations (e.g., soil types, soil compaction, proximity to water, etc.) of burrowing crayfish communities facilitates future management decisions on restoration, reintroduction, and establishment of crayfish dependent species (especially prairie specialists e.g. endangered crawfish frogs) through having more extensive knowledge of burrowing crayfish habitat. The goal of this study was establish baseline information on the distribution of burrowing crayfish in a restored Missouri prairie. This goal was addressed with a series of field surveys that would 1) the potential habitats suitable for burrowing crayfish species, 2) their relative densities in these habitats, 3) what habitat/soil characteristics influence their distribution, and 4) the species composition and their respective distributions.