In this project, researchers are estimating spiny lobster densities within six South Coast MPAs and adjacent reference sites and will relate these estimates to bottom features, such as rocky crevices and understory algae. Commercial lobster fishermen tagged and recaptured lobsters to study “spillover” from closed to open areas, lobster movements and home ranges. Spatially explicit landings data (catch records by location) are also being compiled to calculate catch-per-unit effort inside and outside the MPAs before and after they went into effect. The six MPAs and adjacent reference sites are: (1) Point Vicente State Marine Conservation Area (SMCA); (2) Laguna Beach State Marine Reserve (SMR); (3) Swami’s Beach SMCA; (4) Matlahuayl SMR; (5) South La Jolla SMR; and (6) Cabrillo SMR. Spiny lobsters support a popular recreational and valuable commercial fishery, are a key part of the southern California kelp forest ecosystem, and are a priority species for state managers. Results from this project will help assess the fishery’s stability to current harvesting practices and may be included in the spiny lobster fishery management plan now under development.