Processes and mechanisms that determine the planktonic production in the largest bay inside the Gulf of California, Mexico: a synthesis and review
DOI: https://doi.org/10.3856/vol52-issue5-fulltext-3206
Abstract
The Bay of La Paz (BLP) is located in the southwestern portion of the Gulf of California (GC), the largest and deepest coastal environment along the gulf. The BLP is recognized for its high biological diversity and is a place of refuge, growth, and feeding for several emblematic species, some of which are critically endangered. However, what makes the BLP productive? This paper presents a synthesis and review of the physical processes and mechanisms related to planktonic production, which are directly linked to productivity at higher trophic levels, including top predators. This review reveals that the BLP has a high richness and abundance of plankton species. Several hydrodynamic processes at different scales exert a marked influence on these organisms, including internal waves, hydraulic jumps, thermohaline fronts, the presence of a dipole eddy, and a quasi-permanent cyclonic eddy that is confined to the bay, which induces Ekman pumping that determines the availability of nutrients in the euphotic zone. This eddy induces a differential phytoplankton distribution, with a predominance of dinoflagellates in its center and the dominance of diatoms in its periphery. This arrangement is closely linked to that of zooplankton. Herbivorous zooplankton are highly abundant in the periphery of the eddy, while omnivorous zooplankton are dominant in the center. In contrast, carnivorous zooplankton are dominant in the GC. Although significant progress has been made in understanding the dynamics of the BLP over the last two decades, gaps remain unaddressed. This review highlights the areas of opportunity to continue advancing this endeavor, achieve a better scientific understanding of the region, and propose better management and conservation plans for this highly diverse area.