Small-scale spatial variation in population dynamics and fishermen response in a coastal marine fishery

• Published in: PloS one Vol. 7; no. 12; p. e52837
• Main Authors: Wilson, Jono R, Kay, Matthew C, Colgate, John, Qi, Roy, Lenihan, Hunter S
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 31.12.2012; Public Library of Science (PLoS)
• Subjects: Age; Analysis; Animal Distribution; Animals; Biology; California; Coastal fisheries; Collaboration; Commercial fishing; Conservation; Conservation of Natural Resources; Cooperative Behavior; Decision making; Demographics; Demography; Ecosystem biology; Ecosystems; Environmental science; Evolution & development; Fertility; Fish; Fish populations; Fisheries; Fisheries - methods; Fisheries management; Fisheries research; Fishery management; Fishes - growth & development; Fishes - physiology; Fishing; Growth rate; Heterogeneity; Humans; Innovations; Laboratories; Life history; Management; Management decisions; Marine fish; Models, Biological; Mortality; Oceans and Seas; Overfishing; Population biology; Population Dynamics; Productivity; R&D; Recruitment; Reproduction; Research & development; Scales; Sebastes alutus; Sebastes rastrelliger; Sebastes serranoides; Sedentary species; Small scale; Small-scale fisheries; Spatial distribution; Spatial variability; Studies; Subpopulations; Variability; Wildlife sanctuaries; Yield; California; Mexico; Santa Barbara California; Baja California Mexico; United States > US
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0052837

A major challenge for small-scale fisheries management is high spatial variability in the demography and life history characteristics of target species. Implementation of local management actions that can reduce overfishing and maximize yields requires quantifying ecological heterogeneity at small spatial scales and is therefore limited by available resources and data. Collaborative fisheries research (CFR) is an effective means to collect essential fishery information at local scales, and to develop the social, technical, and logistical framework for fisheries management innovation. We used a CFR approach with fishing partners to collect and analyze geographically precise demographic information for grass rockfish (Sebastes rastrelliger), a sedentary, nearshore species harvested in the live fish fishery on the West Coast of the USA. Data were used to estimate geographically distinct growth rates, ages, mortality, and length frequency distributions in two environmental subregions of the Santa Barbara Channel, CA, USA. Results indicated the existence of two subpopulations; one located in the relatively cold, high productivity western Channel, and another in the relatively warm, low productivity eastern Channel. We parameterized yield per recruit models, the results of which suggested nearly twice as much yield per recruit in the high productivity subregion relative to the low productivity subregion. The spatial distribution of fishing in the two environmental subregions demonstrated a similar pattern to the yield per recruit outputs with greater landings, effort, and catch per unit effort in the high productivity subregion relative to the low productivity subregion. Understanding how spatial variability in stock dynamics translates to variability in fishery yield and distribution of effort is important to developing management plans that maximize fishing opportunities and conservation benefits at local scales.