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Community marine reserves are geographical areas closed to fishing activities, implemented and enforced by the same fishermen that fish around them. Their main objective is to recover commercial stocks of fish and invertebrates. While marine reserves have proven successful in many parts of the world, their success near important marine predator colonies, such as the California sea lion ( Zalophus californianus ) and the Pacific harbor seal ( Phoca vitulina richardii ), is yet to be analyzed. In response to the concerns expressed by local fishermen about the impact of the presence of pinnipeds on their communities’ marine reserves, we conducted underwater surveys around four islands in the Pacific west of the Baja California Peninsula: two without reserves (Todos Santos and San Roque); one with a recently established reserve (San Jeronimo); and, a fourth with reserves established eight years ago (Natividad). All these islands are subject to similar rates of exploitation by fishing cooperatives with exclusive rights. We estimated fish biomass and biodiversity in the seas around the islands, applying filters for potential California sea lion and harbor seal prey using known species from the literature. Generalized linear mixed models revealed that the age of the reserve has a significant positive effect on fish biomass, while the site (inside or outside of the reserve) did not, with a similar result found for the biomass of the prey of the California sea lion. Fish biodiversity was also higher around Natividad Island, while invertebrate biodiversity was higher around San Roque. These findings indicate that marine reserves increase overall fish diversity and biomass, despite the presence of top predators, even increasing the numbers of their potential prey. Community marine reserves may help to improve the resilience of marine mammals to climate-driven phenomena and maintain a healthy marine ecosystem for the benefit of both pinnipeds and fishermen.

1. In dragonflies, species richness shows a marked variation between lineages. Species diversification in this lineage has been linked with habitat variation, but the role of other factors, such as wing pigmentation, arguably one of the most conspicuous traits in dragonflies, have not yet been explored.2. In this study, using novel methodology that takes into account state-dependent speciation, extinction models, and ancestral reconstruction, we investigate the role of wing pigmentation (present/absent) in conjunction with habitat variation (lentic/ lotic), to unveil the drivers of species diversification in dragonflies.3. We found that wing pigmentation is associated with a marginal increase in diversification compared to unpigmented lineages. Inhabiting a lentic habitat is associated with higher diversification rates. When considering both factors in a single model, lentic environments are associated with higher diversification compared to lotic habitats regardless of pigmentation status. In contrast with results across the whole tree, in lotic environments, wing pigmentation is associated with marginally higher diversification rates compared to non-pigmented species. Ancestral state reconstruction revealed that the last common ancestor of dragonflies was most likely non-pigmented and lived in lotic habitats. 4. Our study provides evidence that wing pigmentation in conjunction with habitat has an important influence on dragonflies species diversification, with habitat being a better differentiator than wing pigmentation.

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