Evaluating the protection of diverse and representative coastal and marine habitats within California’s Marine Protected Area (MPA) network

The Marine Life Protection Act of 1999 endeavors to protect the “natural diversity and abundance of marine life” along the California coastline and its nearshore environments, promoting the protection of marine habitats, ecosystems, and natural heritage.1 In pursuit of informing these goals, substantial advances in Marine Protected Area (MPA) habitat measuring have occurred since the initial MPA planning process, particularly in remote sensing and habitat mapping. Under the guidance of researchers involved in the recent decadal evaluation of California’s MPA network, our team evaluated whether the network protects a diverse range of habitats in proportion to their natural abundance within state waters.  

Our team integrated existing spatial habitat datasets to generate map layers representing key habitat components across California state waters. These layers were used to measure habitat abundance and distribution inside the MPAs compared to outside of the network. The greatest difference in both actual and relative habitat abundance between state waters and MPAs was from canopy-forming macroalgal (kelp) cover, with 2.3 percent more coverage and 3.4 percent more coverage respectively.  

Our findings culminated in a written report summarizing this process, which includes effective visualization of key insights through tables, figures, and maps, as well as an interactive dashboard. It is our great hope that this report be used to inform the continued protection and effective management of California MPAs, and be further utilized by researchers engaged with habitat composition analysis for a wide range of applications.  

Acknowledgments 

Bren School: Dr. Carmen Galaz García, Assistant Teaching Professor; Cori Lopazanski, PhD Candidate,  Samantha Stevenson-Karl, Associate Professor 

Monterey Bay Aquarium: Joshua Smith, Ocean Conservation Research Scientist