Mollusc and crustacean fisheries in mangroves of Magdalena-Almejas Bay, Baja California Sur, Mexico

To determine changes in the catches of mollusks and crustaceans associated with mangrove areas in the lagoon complex of Magdalena-Almejas Bay and the possible impact of medium-term environmental variability, production trends derived from data recorded by the National Commission of Aquaculture and Fisheries from 1992 to 2021 were analyzed. In addition, possible relationships were established with environmental conditions associated with El Nino-La Nina periods based on sea surface temperature values. The fisheries included in the analysis targeted the following species: the black arks ( Anadara tuberculosa), ), Pacific calico scallops ( Argopecten ventricosus), ), squalid callista clams ( Megapitaria squalida), ), Californian venus clams ( Chione californiensis), ), pen shells ( Pinna rugosa and Atrina maura), ), and the Murex snails the black and pink ( Hexaplex nigritus and Phyllonotus erythrostomus). ). Blue shrimp ( Penaeus stylirostris), ), brown shrimp (P. P. californiensis), ), and green swimming crab ( Callinectes bellicosus) ) were also considered. The results showed variability among the series for each fishery, with positive trends for black arks, Californian venus clams, and Chinese snails, and negative trends for Pacific calico scallops, squalid callista clams, and shrimps. The most frequently occurring changes appeared to be cyclic and related to variations in environmental conditions. However, we concluded that it is difficult to differentiate and quantify the possible effects on resource availability due to fishing or modifications in mangroves, habitat conditions, and their impact on biological processes such as reproduction, feeding, growth, mobility, and recruitment.