Density of mysis of Penaeus aztecus Ives, 1891 on a reef in the Southwest of the Gulf of Mexico

Background. The Parque Nacional Sistema Arrecifal Veracruzano (PNSAV) is in the southern Gulf of Mexico and supports an important shrimp fishery based on three species of Dendrobranchiata: the brown shrimp, Penaeus aztecus, the white shrimp, P. setiferus and the pink shrimp, P. duorarum. Objective. Analyze the distribution and abundance of P. aztecus during the mysis stage and determine its relationship with environmental factors in the PNSAV. Methods. We measured temperature, salinity, and dissolved oxygen in situ. The planktonic samples from four transects were collected during cold fronts and rainy weather conditions from 2011 to 2013. Results. In rainy conditions the temperature varied from 27.49 ± 0.46 to 29.98 ± 0.02°C, salinity from 32.18 ± 0.06 to 35.40 ± 0.52, and dissolved oxygen from 3.64 ± 0.13 to 6.18 ± 0.64 mgL-1; during cold fronts the temperature varied from 23.21 ± 0.05 to 25.74 ± 0.37 °C, salinity from 34.59 ± 0.39 to 35.84 ± 0.17, and dissolved oxygen from 4.04 ± 0.06 to 6.02 ± mgL-1. The highest average density with 6,938 ± 326 mysis 100 m−3, was found during rainy season in 2011 in the southern transect nearshore, followed by 3,321 ± 339 mysis 100 m−3 in the offshoresouth-central transect during cold fronts weather conditions in 2013, and 3,056 ± 236 mysis 100 m−3 in the south-central foreshore transect during cold fronts weather condition in 2011. Conclusions. The highest density of P. aztecus during mysis stage was recorded in southward foreshore area from PNSAV, during rainy conditions and related to large values of dissolved oxygen concentrations.