Marine protected areas (MPAs) have gained attention as a conservation tool for enhancing ecosystem resilience to climate change. However, empirical evidence explicitly linking MPAs to enhanced ecological resilience is limited and mixed. To better understand whether MPAs can buffer climate impacts, we tested the resistance and recovery of marine communities to the 2014–2016 Northeast Pacific heatwave in the largest scientifically designed MPA network in the world off the coast of California, United States. The network consists of 124 MPAs (48 no‐take state marine reserves, and 76 partial‐take or special regulation conservation areas) implemented at different times, with full implementation completed in 2012. We compared fish, benthic invertebrate, and macroalgal community structure inside and outside of 13 no‐take MPAs across rocky intertidal, kelp forest, shallow reef, and deep reef nearshore habitats in California's Central Coast region from 2007 to 2020. We also explored whether MPA features, including age, size, depth, proportion rock, historic fishing pressure, habitat diversity and richness, connectivity, and fish biomass response ratios (proxy for ecological performance), conferred climate resilience for kelp forest and rocky intertidal habitats spanning 28 MPAs across the full network. Ecological communities dramatically shifted due to the marine heatwave across all four nearshore habitats, and MPAs did not facilitate habitat‐wide resistance or recovery. Only in protected rocky intertidal habitats did community structure significantly resist marine heatwave impacts. Community shifts were associated with a pronounced decline in the relative proportion of cold water species and an increase in warm water species. MPA features did not explain resistance or recovery to the marine heatwave. Collectively, our findings suggest that MPAs have limited ability to mitigate the impacts of marine heatwaves on community structure. Given that mechanisms of resilience to climate perturbations are complex, there is a clear need to expand assessments of ecosystem‐wide consequences resulting from acute climate‐driven perturbations, and the potential role of regulatory protection in mitigating community structure changes.
Marine species with pelagic larvae typically exhibit little population structure, suggesting long‐distance dispersal and high gene flow. Directly quantifying dispersal of marine fishes is challenging but important, particularly for the design of marine protected areas (MPAs). Here, we studied kelp rockfish (
- PAR ID:
- 10461231
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Molecular Ecology
- Volume:
- 28
- Issue:
- 7
- ISSN:
- 0962-1083
- Page Range / eLocation ID:
- p. 1611-1623
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Marine protected areas (MPAs) aim to protect habitats and ecosystems to promote the diversity and health of marine populations. To evaluate the health of fish populations within and outside of MPAs in Southern California, we used flight initiation distance (FID). FID is the distance at which an individual will flee from a perceived predator and is a direct measure of boldness. Lower FIDs are indicative of bolder populations. Lower FID values indicate that fish will have the opportunity to dedicate less energy to fleeing from predators which could then be used for increased foraging. Data was collected from eight locations along the Southern California coast, four in protected areas and four in non-protected areas. FIDs were measured with a sonar-based range finder. All fish species that recreational fishermen could catch were targeted, with a focus on six core species spearfishermen catch commonly. Results showed that all fish sampled in MPAs have significantly lower FIDs than those in non-protected areas. An ANOVA showed no significant difference between different locations of the same protected status. The six core species had lower average FIDs in protected areas, three species had significant differences between protected and non-protected populations, and there was no significant difference in FIDs between species. These results show that Southern California MPAs are promoting healthier fish communities with respect to boldness behavior. This data and methods can be implemented in future projects to expand the range of metrics measured to inform management tools for California’s MPAs and MPAs at large.
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