Effects of Human Population Density and Proximity to Markets on Coral Reef Fishes Vulnerable to Extinction by Fishing

Coral reef fisheries are crucial to the livelihoods of tens of millions of people; yet, widespread habitat degradation and unsustainable fishing are causing severe depletion of stocks of reef fish. Understanding how social and economic factors, such as human population density, access to external markets, and modernization interact with fishing and habitat degradation to affect fish stocks is vital to sustainable management of coral reef fisheries. We used fish survey data, national social and economic data, and path analyses to assess whether these factors explain variation in biomass of coral reef fishes among 25 sites in Solomon Islands. We categorized fishes into 3 groups on the basis of life-history characteristics associated with vulnerability to extinction by fishing (high, medium, and low vulnerability). The biomass of fish with low vulnerability was positively related to habitat condition. The biomass of fishes with high vulnerability was negatively related to fishing conducted with efficient gear. Use of efficient gear, in turn, was strongly and positively related to both population density and market proximity. This result suggests local population pressure and external markets have additive negative effects on vulnerable reef fish. Biomass of the fish of medium vulnerability was not explained by fishing intensity or habitat condition, which suggests these species may be relatively resilient to both habitat degradation and fishing. Las pesquerías de arrecifes de coral son cruciales para el sustento de decenas de millones de personas; sin embargo la amplia degradación del hábitat y la pesca no sustentable están causando la disminución severa de peces de arrecife. El entendimiento de la interacción de factores sociales y económicos — como la densidad de la población humana, el acceso a los mercados externos, y la modernización — con la pesca y la degradación del hábitat y su efectos sobre las poblaciones de peces es vital para el manejo sustentable de las pesquerías en los arrecifes. Utilizamos información de censos de peces, datos nacionales sociales y económicos y análisis de vías para comprobar si estos factores explican la variación en la biomasa de peces de arrecifes de coral en 25 sitios en las Islas Salomón. Clasificamos a los peces en 3 grupos con base en las características de la historia de vida asociadas con la vulnerabilidad a la extinción de los peces (vulnerabilidad alta, media y baja). La biomasa de los peces con vulnerabilidad baja