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Abstract The changing global climate is having profound effects on coastal marine ecosystems around the world. Structure, functioning, and resilience, however, can vary geographically, depending on species composition, local oceanographic forcing, and other pressures from human activities and use. Understanding ecological responses to environmental change and predicting changes in the structure and functioning of whole ecosystems require large‐scale, long‐term studies, yet most studies trade spatial extent for temporal duration. We address this shortfall by integrating multiple long‐term kelp forest monitoring datasets to evaluate biogeographic patterns and rates of change of key functional groups (FG) along the west coast of North America. Analysis of data from 469 sites spanning Alaska, USA, to Baja California, Mexico, and 373 species (assigned to 18 FG) reveals regional variation in responses to both long‐term (2006–2016) change and a recent marine heatwave (2014–2016) associated with two atmospheric and oceanographic anomalies, the “Blob” and extreme El Niño Southern Oscillation (ENSO). Canopy‐forming kelps appeared most sensitive to warming throughout their range. Other FGs varied in their responses among trophic levels, ecoregions, and in their sensitivity to heatwaves. Changes in community structure were most evident within the southern and northern California ecoregions, while communities in the center of the range were more resilient. We report a poleward shift in abundance of some key FGs. These results reveal major, ongoing region‐wide changes in productive coastal marine ecosystems in response to large‐scale climate variability, and the potential loss of foundation species. In particular, our results suggest that coastal communities that are dependent on kelp forests will be more impacted in the southern portion of the California Current region, highlighting the urgency of implementing adaptive strategies to sustain livelihoods and ensure food security. The results also highlight the value of multiregional integration and coordination of monitoring programs for improving our understanding of marine ecosystems, with the goal of informing policy and resource management in the future.
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Revealing genetic patterns across ecoregions in the northeastern Pacific of California and Baja California
Abstract AimWe reconstructed the genetic patterns and identified the main genetic breaks of several taxa across California and Baja California coast. Additionally, we evaluated the contribution of different variables to the level of structure. LocationCalifornia and Baja California coast. TaxonFish, invertebrates, algae, seagrass and mammals. MethodsWe generated a map to reconstruct the genetic patterns using genetic information (Fst index and phylogenetic clades distribution) from a literature review of population genetics publications from 2000 to 2023. For the analysis of genetic connectivity drivers, we explored the effect of different variables representing life history traits, reproductive strategies and biogeographic variables and generated five working hypotheses which were evaluated with generalized linear models (GLMs). ResultsWe identified 42 genetic breaks from 63 species across our study area. The largest number of breaks occurs from 27° N to 29° N and from 31° N to 35° N. This range includes transition zones between ecoregions such as Punta Eugenia, Baja California, Mexico and Point Conception, California, USA. We also identified Ensenada, Baja California region as a barrier to gene flow. From a transboundary perspective, we found 40 species with connectivity between California and Baja California, including 14 commercial and or recreational species. We found none of the variables explored had a clear effect on the level of genetic differentiation of the species assessed in the region. Main ConclusionGenetic breaks among different taxa do not distribute randomly across the latitudinal range from California and Baja California coastal area, rather they are mainly located in transition zones between marine ecoregions. The challenge to identify specific variables that explain general genetic patterns highlights the complexity that drives population connectivity processes in marine species.
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- Award ID(s):
- 1925771
- PAR ID:
- 10544274
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Journal of Biogeography
- ISSN:
- 0305-0270
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1111/jbi.14988
