Annual abundance variation of Farfantepenaeus californiensis (Holmes 1900) in the Gulf of Tehuantepec

Abstract

The annual abundance variation of recruits (FR index) and spawners (DA index) of Farfantepenaeus californiensis
(Holmes 1900) was modeled with age groups related with the natural processes of recruitment and reproduction in the
Gulf of Tehuantepec (GT). The FR Index was modeled using the age group of four months and the DA index with the age
groups from six to 11 months. The relationships between the sea surface temperature (SST) and both population indices
from 1989 to 1998 were quantified, between these and the concentration of the Chlorophyll a (Cla) from November 1996

to May 1998. In both intervals, the SST had a correlation directly proportional with FR and inversely proportional with
DA. In the second interval, the Cla was greater during the two maximums abundance DA (R = 0.5627) and lesser during
the maximum FR (R = ?0.6887). The correlation between the SST and Cla was estimated in ?0.6452. Between October/
November and January, the spawners abundance was greater than the abundance of recruits. The maximums DA
agreed with maximums of Cla and minimum SST during the nortes season or tehuanos. The massive recruitment to
the marine environment was observed in July and August/September when the oceanographic conditions in the GT
were inverse to described for the DA index. The annual abundance variation of the FR and DA indices remains constant
with the presence of El Niño in the GT, but its abundance diminishes.