Population dynamics of the crayfish Cambarellus chapalanus from the San Juan Cosalá Mountain Range, Jalisco, Mexico

Abstract

Cambarellus chapalanus is an endemic species of the area around Lake Chapala in Mexico and knowledge about its biology and ecology is scarce. Its population dynamics were evaluated based on individual growth, mortality, production, and productivity. For this, individuals were collected between November 2011 and October 2012, in ponds located in the Sierra San Juan Cosalá, Jalisco, Mexico. The abiotic variables of ponds (depth, temperature, pH, precipitation, and evaporation) presented significant variations during the study. Abundance was similar throughout the year but was related to an increase in temperature and evaporation of ponds. Furthermore, males were more abundant than females. Growth was fast and oscillatory with slow phases in rainy periods. Mortality was high and started at medium sizes; however, high somatic production also generated high population productivity. In general, the parameters of C. chapalanus showed normal patterns for a natural population; however, were strongly influenced by temperature and pond volume, probably because it is an isolated population in Sierra San Juan Cosalá.