California Sea Grant College Program

No-take marine reserves have become a popular tool in fisheries management worldwide; ever, many aspects of their design, including optimal size and location, are still debated. This is due, in part to a lack of critical knowledge on behavior of many exploited marine organisms. Because a primary application of no-take marine reserves is to protect adult reproductive stock, which may serve to supply larvae and juveniles to adjacent unprotected areas, reserves must be large enough at minimum to encompass the daily movement patterns of adult fishes. Previous studies on home range sizes and site fidelity of kelp bass and sheephead in California marine reserves have suggested that habitat composition may influence the size and shape of home ranges, and that breaks in habitat may serve as natural barriers, restricting the home ranges of some fishes. Surprisingly, little is known about how habitat composition, quality and gradients may influence home range sizes and site fidelity of nearshore kelp bed fishes. Knowing fish-habitat relationships and how habitat edges affect fish movement will allow managers to site reserves knowledgeably with goals of optimizing “leaky” boundaries that allow for spillover into the fishery or “tight” boundaries that minimize movements of fish across the boundary.