RELATIVE GROWTH OF CARDISOMA CRASSUM SMITH, 1870 (DECAPODA: GECARCINIDAE) IN THE ESTUARY EL SALADO, PUERTO VALLARTA, JALISCO MEXICO

Abstract

The growth of organisms is accompanied by changes in proportion and size, and it is known as relative or allometric growth. C. crassum is one of the largest crab species it inhabits mangrove forests in the Eastern tropical Pacific, however, the data of this specie is deficient and limited to a few records. Therefore, the aim of this work was to estimate the growth of C. crassum in El Salado stream, Puerto Vallarta, Jalisco, Mexico. A total of 252 organisms were captured in the rainy season, which were marked and released after assessments. The Huxley equation was used to determine allometry and to estimate the condition factor (K) and the growth rate. The sex ratio was 1:1.72, favoring females. The range of the condition factor in females was between 0.02 and 0.06 g/cm3. In ovigerous females the K mínimum value was 0.03 and the maximum value was 0.08 g/cm3; for males the K minimum was 0.03 and the maximum was 0.14 g/cm3. A K=0.88 was obtained and Lmax=95.1 mm. There were no significant differences in CA between sexes, neither in PO. While differences could be observed in LQ and AQ between sexes. It was concluded that C. crassum growth is similar to another gecarcinid species in El Salado. Males reach larger sizes than females and the condition factor is similar between males and non-ovigerous females, but there are significant differences between the condition factor in females and ovigerous females.