Sustainable management of commercial bivalves in the Eastern Tropical Pacific requires an in-depth understanding of their bionomics in response to seasonal oceanographic variability. This study evaluated the growth and mortality dynamics of Leukoma asperrima in the Gulf of Panama over an annual cycle (November 1995 – October 1996). The population exhibited a mean shell length of 25.99 mm and a total weight of 7.05 g, with significant fluctuations associated with the coastal upwelling regime. Results revealed non-uniform growth across cohorts; the highest longitudinal increment rate was recorded in intermediate-sized individuals (0.109 mm/month), whereas maximum weight gain (0.13 g/month) was observed in larger specimens, suggesting high efficiency in phytoplankton assimilation during the rainy season. Average monthly mortality was 11.3%, with critical peaks in October (21.5%) and January (19.42%) linked to post-reproductive stress and senescence. The detection of endoparasites in gonadal tissue is postulated as a determining factor in tissue disorganization and adult survival. These findings highlight the importance of environmental and pathological factors in regulating L. asperrima biomass, providing critical parameters for the implementation of fisheries exploitation models.
