Rocky intertidal ecosystems in urbanized southern California: Long-term change, human impacts, and management
By Dr. Jayson Smith, California State Polytechnic University, Pomona
Rocky intertidal habitats are located at the interface between land and the sea and are incredibly diverse despite being naturally harsh habitats due to stresses associated with, for example, frequent aerial exposure during low tides and high wave disturbance. In heavily urbanized southern California, human impacts, including visitation, exploitation, climate change, pollution, and introduced species, can further add to these stresses, resulting in long-term changes in the abundances and distributions of marine flora and fauna. For example, long-term monitoring with the Multi-Agency Rocky Intertidal Network (MARINe) has detected decadal declines in rockweeds and mussels and population crashes in abalone, sea stars, and urchins. While multiple stressors have likely contributed to changes, the detrimental effects of human visitation are particularly evident in southern California where tidepooler usage can be extreme at easily accessible locations. Visitor behaviors, such as collecting and trampling, can result in declines in target or sensitive species, shifts in the size and age structure of populations, and other cascading ecological effects. Marine Protected Areas, combined with local stakeholder investment and management, can mediate these impacts while restoration of ecologically important taxa can increase recovery rates and improve resilience. Understanding long-term patterns, effects of humans, and effectiveness of management and restoration approaches in rocky intertidal ecosystems are imperative as we look ahead towards future climate changes, including increases in the frequency and intensity of marine heatwaves, sea level rise, and ocean acidification.
Dr. Jayson Smith received a Bachelor’s degree from the University of California, Los Angeles (UCLA) and a Master’s degree at California State University, Fullerton before returning to UCLA for his doctorate. Now an Associate Professor of Biology at California State Polytechnic University, Pomona, he teaches a variety of marine and environmental biology courses, including field courses on Catalina and in Hawaii. Dr. Smith conducts research in rocky intertidal habitats of heavily urbanized southern California, focusing on long-term monitoring and change, marine protected areas, human impacts and management, restoration, and introduced seaweeds. He is an active researcher with the coast-wide Multi-Agency Rocky Intertidal Network (MARINe) and participates in local conservation efforts with the Laguna Ocean Foundation and the Orange County Marine Protected Area Council. His research has been funded by the Bureau of Ocean Energy Management, USC Sea Grant, California Sea Grant, and the Ocean Protection Council.
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