Allometry of the Growth of Pink ShrimpFarfantepenaeus duorarumin a Subtropical Bay

Abstract

We developed robust allometric relationships for pink shrimp Farfantepenaeus (=Penaeus) duorarum by focusing on appropriate mathematical models and statistical procedures for parameter estimation. We utilized fishery-independent data on the abundance and size of juvenile and subadult pink shrimp from an efficient sampling program in Biscayne Bay, Florida. Total length (TL), carapace length (CL), and wet weight (W) were obtained from 440 male and 487 female pink shrimp ranging from 3 to 30 mm CL. The TL−CL function was linear. Because we noticed a pronounced shift in the relationship at the onset of sexual maturity, however, we estimated separate models for juveniles (CL < 18 mm; TL = 1.616 + 4.503·CL) and subadults (CL ≥ 18 mm; TL = 11.636 + 3.985·CL). The dependence of W on CL was best described by nonlinear allometric functions of the form W = αCLβ. Model parameters were estimated by least-squares regression methods after log-transformation of the original nonlinear power function. The allometric function for males (W = 0.000731·CL3.024) was significantly different from that for females (W = 0.000865·CL2.951), which strongly indicates the existence of dimorphic growth for pink shrimp.