Award: DEB-1212124

The ecosystems and associated small-scale fisheries of Baja California, Mexico, have been affected by ENSO events, with significant decline in key resources during the extreme events of 1982-83 and 1997-98. Climate-driven low-oxygen events (hypoxia) have also been documented in coastal areas of the California Current region, including Baja California, resulting in high mortality of ecologically and commercially important nearshore marine species. This project investigated the impacts of oceanographic variability on coastal marine ecosystems and human communities of the Pacific coast of Baja California, Mexico, and the influences of local and global feedbacks on the resilience and adaptive capacity of these systems. We (1) characterized coastal oceanographic variability and the patterns and drivers of hypoxic events; (2) assessed the impacts of coastal oceanographic variability, particularly heat waves and hypoxic events, on nearshore species, ecosystems, and fisheries; and (3) assessed the cultural, social, and economic variables that influence the responses of local communities to these impacts, particularly their willingness and ability to invest in local conservation and adaptation. Coastal oceanographic studies have highlighted extreme, prolonged low oxygen events and associated mass mortalities of marine invertebrates. Analyses of oceanographic data revealed high local variability and differential exposure to warming and hypoxia at sites only a few km from each other. Such local variability provides opportunities for local conservation and adaptation actions and can be leveraged for siting marine reserves, artificial reefs, outplants for restocking depleted populations, and mariculture. This project has created an unprecedented monitoring network and infrastructure along the Pacific Coast of Baja California, enabling twelve fishing communities to track change in their marine environments and incorporate this information in their marine management. Kelp forest ecosystem monitoring have revealed large declines of benthic invertebrates, and stable or increasing fish abundances. Controlled field and laboratory experiments have shown that the low oxygen and high temperatures that have affected this region are likely drivers of the declines. A broader regional analysis showed that these community changes have occurred throughout the southern portion of the range of distribution of giant kelp, in response to warming events. Population models suggest that a network of marine reserves can have a direct positive effect on abalone population abundance and reduce the risk of population and fisheries collapse, particularly under increasing frequency of extreme events. Interviews and game theory experiments revealed that fishers voluntarily reduce fishing pressure to counteract or buffer the effects of environmental change. Environmental stewardship in the face of uncertainty, in this context, is contingent on strong communication, strong institutional organization and capacity, and past exposure to uncertainty and change. The project has provided training opportunities for 6 undergraduate and 12 graduate students, 8 postdocs, and 12 research associates and technical staff in the USA and Mexico. Results have been broadly shared in publications, reports, seminars, conferences, and through routine meetings with fishers, fishing cooperative staff, community members, government agencies, and academic institutions in Mexico and the USA. Last Modified: 12/12/2018 Submitted by: Fiorenza Micheli