Spatial distribution of effort by artisanal fishers: Exploring economic factors affecting the lobster fisheries of the Corn Islands, Nicaragua

Abstract

1Spatial distribution of fishing effort is increasingly recognised as an important consideration for fisheries 2 management, as it can affect trends in catch rates, and be incorporated into planning of spatial management tools 3 like marine protected areas (MPAs). One-hundred and ninety-eight household questionnaires provided a coarse 4 indication of effort distribution of artisanal lobster fishers around the Corn Islands, and 32 semi-structured 5 interviews with skippers were used to map individual fishing sites and describe the operating costs and revenues 6 of typical dive and trap-fishing operations. Artisanal fisheries had ranges of up to 50 km, and had moved 7 significantly offshore within the previous 10 years. At the scale of a 5 x 5 minute lat/long grid, trap fishing effort 8 was highly aggregated (dispersion coefficient = 3.5), while diving had a regular dispersion (d.c. = 0.1). 9Descriptions of catch composition at each site showed a clear spatial pattern in the distribution of two locally-10 recognised types of lobster potentially indicating local stock structures. Economic information was summarised 11 into balance sheets for typical fishers and suggested that fuel accounted for about 52 and 37% of the operating 12 costs of dive and trap fishing captains respectively. Qualitative questions highlighted trap theft, adoption of 13 geographical positioning system (GPS) technology and fuel costs as major factors affecting spatial behaviour. 14 The costs and benefits of using more distant grounds were examined by testing for relationships between stated 15 typical catch rates and distance of 90 trap-fishing grounds; and between fuel expenditure and catches in 291 16 daily records of the activities of 3 divers. Maximum catch rates stated by trap fishers were significantly higher at 17 more distant sites and daily catches by the divers had a positive relationship with fuel expenditure, which 18 suggested that increasing fuel expenditure to target more distant sites would lead to higher gross revenue as well 19 as higher net revenues, after considering variable operating costs. Thus there appears to be an economic 20 incentive to extend the range of the fishery. However, fishers may not perceive these positive trends in catch rate 21 with distance due to catch variability, and costs other than fuel complicate the trade-off between catch and 22 distance. 23

The social–ecological system framework as a knowledge classificatory system for benthic small-scale fisheries

“…Castilla and Jerez (1986) RS2 -Clarity of system boundaries Biophysical characteristics that make feasible for actors to determine where the resource system starts or ends Foale (1998) RS3 -Size of resource system Absolute or relative descriptions of the spatial extent of a resource system ) Daw (2008 …”

Dinámica espacio-temporal del esfuerzo en una pesquería de buceo artesanal multiespecífica y sus efectos en la variabilidad de las capturas: Implicaciones para el manejo sostenible

“…El poco peso que tuvieron las variables económicas en la variación de captura promedio total por viaje de pesca en los GAMs reafirma lo encontrado por otros estudios que han analizado pesquerías de la misma naturaleza. Por ejemplo, Daw (2008) encontró que en las decisiones sobre la elección de sitios de pesca de los pescadores que capturan langosta en Nicaragua, se tienen en cuenta una compleja gama de aspectos más que la simple relación costo-captura que ha sido muy utilizada en análisis económicos reduccionistas en pesquerías. En nuestro caso, el poco efecto de las variables económicas indica que las propiedades de los métodos de pesca implican bajos costos de operación tal como lo reporta Naranjo (2010) al estudiar algunos aspectos económicos de la pesca de langosta con el empleo de los métodos de buceo analizados.…”

“…Pesquerías multi-específicas asociadas a métodos de buceo en América Latina ejercen alta presión de pesca sobre recursos bentodemersales, no solo por su alto valor comercial sino como seguridad alimentaria (Defeo & Castilla, 2005;FAO, 2006;Daw, 2008). En este tipo de pesquerías es común que los pescadores perciban disminución en los recursos y como efecto compensatorio aumenten el esfuerzo efectivo.…”

“…Para este fin, se contrastó la información de dos temporadas de pesca de los diferentes métodos de buceo, y se analizó la composición de especies, las fuentes de variación de las capturas, los patrones espacio-temporales del esfuerzo y se identificó las especies objetivo. Se partió del supuesto de que los pescadores desarrollan adaptaciones a sus estrategias en el tiempo y el espacio, cuando ven afectados sus retornos económicos con cambios en las capturas (Béné & Tewfik, 2001;Daw, 2008). Se discuten los resultados de este trabajo con el fin de derivar aspectos relevantes en el manejo sostenible de especies susceptibles y de la actividad pesquera en general.…”

Life, Fish and Mangroves : Resource Governance in Coastal Cambodia

“…For example, ten scholarly articles discussing gear theft within the fisheries sector were found in Scholar's Portal (a main database for social sciences research) between 2000 and 2010. What this scarce literature suggests is that fishers may travel further distances to avoid traps getting stolen (Daw 2008) and require extensive support in monitoring and surveillance if this problem is to be solved (Al-Masroori et al 2009). This does not help me better to analyze the situation in Koh Sralao; nothing is written about how local institutions may be involved in solving this type of issue.…”