Regresar

Call survey indicates rainbow trout farming alters glassfrog community composition in the Andes of Ecuador

Abstract:

Aquaculture, the farming of fish for human consumption and/or trade, is a growing industry throughout the world. The effects of farming on local ecosystems and wildlife are understudied, particularly in regions where farms are often limited to subsistence practices with little to no government regulation. The influence of Rainbow Trout (Oncorhynchus mykiss) farms on glassfrog community composition was assessed in the Mindo and Alambi regions of Ecuador. Call surveys were conducted during the dominant glassfrog reproductive season (March-May 2017) across 13 sites, six of which were in the immediate proximity of trout farms. Nonmetric multidimensional scaling ordination analyses and multiple response permutation procedures indicate that glassfrog communities differed between trout farm and non-trout farm sites (MRPP; A = 0.11, P = 0.04). Differences in glassfrog community composition were significantly or marginally correlated with percent canopy openness, dissolved oxygen (mg/L), conductivity (μS), and total dissolved solids (mg/L), environmental characteristics altered by the aquaculture practice. As the prevalence of trout farms increases across this region, it is likely that the glassfrog community composition will be altered, potentially resulting in a pattern of decreased species richness. It is also likely that habitat changes associated with trout farming practices including deforestation, water chemistry changes, and predation pressures by escaped trout will influence glassfrog species persistence. Mitigation strategies including improved barriers to decrease trout escape, the incorporation of settling ponds to decrease stream contamination, and the preservation of habitat in areas of high amphibian species richness are warranted.