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USC Dornsife Scientific Diving: The California Spiny Lobster

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


By Alyssa Dykman

In the cool waters of the Eastern Pacific Ocean lies the California spiny lobster. The lobster, Panulirus interruptus, can be found on the rocky substrates of the coastal ocean floor between Monterey Bay, California and the northwestern coast of Mexico. A majority of the population is found off the coastline from Point Conception southwards, to the Channel Islands, and Cortes Bank (Duffy, 1973). In southern California, the California spiny lobster primarily lives in the dynamic kelp forests of the region.

The California spiny lobster is an irreplaceable member of the kelp forest ecosystem. One of the most important ecosystem services the lobsters provide is maintaining the population of sea urchins, which otherwise consume kelp. The lobsters keep the ecosystem in check by protecting the vitality of its foundation, and by taking on the role of a keystone species. However, since the late nineteenth century, humans have found a keen interest in the recreational and commercial fishing of lobsters. The California spiny lobster has been increasingly hunted, and their average size and lifespan has been significantly reduced, putting an entire ecosystem at risk.


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The California spiny lobster has become highly profitable. Due to the lobster’s rising popularity, humans have sought increasingly to catch them legally and illegally. The California Department of Fish and Game have implemented various measures to ensure sustainable lobster fisheries, however the rules are often broken. In terms of illegal lobster catching in southern California, fishermen often get in trouble by hunting in Marine Protected Areas (MPA), which are prevalent throughout the California coastal region.

The Marine Life Management Act, passed in 1999, helps define and manage MPA’s in their distinctive regions (California Department of Fish & Game). The MPA’s seek to conserve the native ecosystem, and they have strict and specific fishing regulations that improve organisms’ size, abundance, and biomass compared to non-reserve locations (Kay, Lenihan, Kotchen, & Miller, 2012). In a recent study, Kay et. al (2012) examined lobster catches in marine reserves compared to non-reserve areas in the Santa Barbara Channel Islands. They found an average of 5.49 more legal-sized lobsters caught per trap in marine reserve areas compared to traps outside reserves, therefore demonstrating the effectiveness of MPA’s (Kay et. al, 2012).

The California Department of Fish and Game established a Fishery Management Plan (FMP) for the California spiny lobster in 2009, as required by the Marine Life Management Act (California Department of Fish & Game). The FMP mandates the public to get involved in the process of assessing the value of MPA’s to local lobster fisheries (California Department of Fish & Game). Specific to southern California is the Southern California Marine Life Protection Act, which established MPA’s of the region to be effective January first of this year. Thus, lobster hunting in southern California has become more tightly regulated and will be evaluated more often.

The most frequent violations in California spiny lobster hunting is catching more than seven lobsters, which is the daily limit, and having possession of underweight lobsters, or ‘shorts’ (Duffy, 1973). It takes a lobster up to a decade to reach the legal size limit. When the lobsters are overfished, the average age of the take is reduced, compromising mating patterns and future generations of the species.

Another requirement of California spiny lobster hunting is they have to be caught by hoop nets or bare hands, not by any mechanism that allows for large quantities to be caught (California Department of Fish & Game). Scuba divers can easily catch lobsters by hand, especially at night when they are more active. Recently, a southern California citizen became the first person to violate the newly effective MPA guidelines this past January, by poaching 47 California spiny lobsters at the Laguna Beach State Marine Reserve (Department of Fish and Game News). The citizen was fined over $20,000 and sentenced to a week in jail for this crime. (Department of Fish and Game News).

Not only is the California spiny lobster important to the kelp forest inhabitants, but humans have noticed their immense value as well. In order to not exploit another sector of the world’s depleting fisheries, citizens, particularly of the southern California region, must more sustainably manage this crustacean. Next week I am off for a weeklong trip to Catalina to practice research diving methods, before traveling to Guam and Palau for research. I hope to see the California spiny lobster in its native environment next week.

About the Author: Alyssa Dykman is a sophomore in the USC Dana and David Dornsife College of Letters, Arts and Sciences working towards a BS degree in Environmental Studies and a minor in Psychology and Law. Alyssa has a strong interest in environmental policy and hopes to pursue a career in Environmental Law.

Works Cited:

California Department of Fish & Game. (2012). California Spiny Lobster Fishery Management Plan. Web. 9 May 2012.

California Department of Fish & Game. (2012). Invertebrates of Interest: California Spiny Lobster. Web. 7 May 2012.

Department of Fish and Game News. (2012). DFG and Orange County Successfully Prosecute First MPA Violation. Web. 10 May 2012.

Duffy, J.M. (1973). Marine Resources Technical Report. California Department of Fish and Game, 10, 1-15.

Kay, M.C., Lenihan, H.S., Kotchen, M.J., & Miller, C.J. (2012). Effects of Marine Reserves on California Spiny Lobster are Robust and Modified by Fine-Scale Habitat Features and Distance from Reserve Borders. Marine Ecology Progress Series, 450, 137-150.

Editor’s note: Scientific Research Diving at USC Dornsife is offered as part of an experiential summer program offered to undergraduate students of the USC Dana and David Dornsife College of Letters, Arts and Sciences. This course takes place on location at the USC Wrigley Marine Science Center on Catalina Island and throughout Micronesia. Students investigate important environmental issues such as ecologically sustainable development, fisheries management, protected-area planning and assessment, and human health issues. During the course of the program, the student team will dive and collect data to support conservation and management strategies to protect the fragile coral reefs of Guam and Palau in Micronesia.

Instructors for the course include Jim Haw, Director of the Environmental Studies Program in USC Dornsife, Assistant Professor of Environmental Studies David Ginsburg,, SCUBA instructor and volunteer in the USC Scientific Diving Program Tom Carr and USC Dive Safety Officer Gerry Smith of the USC Wrigley Institute for Environmental Studies

Previously in this series:

Catching Up with Scientific Diving at USC Dornsife: Surfgrass Monitoring at Catalina

Catching up with Scientific Diving at USC Dornsife: The Robot Submarine

Catching up with Scientific Diving at USC Dornsife: Diving into the Aquarium of the Pacific

USC Dornsife Scientific Diving: Moving Forward to Guam and Palau 2012

USC Dornsife Scientific Diving: Finding My Career Through This Course

USC Dornsife Scientific Diving: The Devaluation of Ecosystem Services

USC Dornsife Scientific Diving: Why USC Dornsife was the Right Decision For Me

USC Dornsife Scientific Diving: Why Experiential Learning is Vital to Academic Life

USC Dornsife Scientific Diving: My Walden South of Los Angeles

USC Dornsife Scientific Diving: Crown-of-Thorns Outbreaks and Anthropogenic Pollution

USC Dornsife Scientific Diving: The International Policy Rationale for the Military Buildup on Guam and Some Environmental Drivers

USC Dornsife Scientific Diving: Marine Ecology from Antarctica to Micronesia

USC Dornsife Scientific Diving: Palau Water Supply

USC Dornsife Scientific Diving: The Contributions of J. S. Haldane to Dive Safety

USC Dornsife Scientific Diving: Human Impacts on Mangrove Forests

USC Dornsife Scientific Diving: Global Sea Cucumber Fisheries

USC Dornsife Scientific Diving: Palauan Mermaids

Dr. Jim Haw is Ray R. Irani Professor of Chemistry and director of the Environmental Studies Program in the USC Dana and Dornsife College of Letters, Arts and Sciences. He is also a scientific, technical and recreational diver.

More by Jim Haw