Effects of Noncompliance on the Success of Alternative Designs of Marine Protected‐Area Networks for Conservation and Fisheries Management

Abstract

Studies examining the efficacy of marine protected areas (MPAs) rarely consider the potential for noncompliance. Violation of MPAs will typically occur near boundaries, so perimeter-to-area ratios will be important determinants of actual protection, suggesting that MPAs should be larger and likely fewer. If larval dispersal is highly localized, however, MPAs will need to be more numerous, widespread, and likely smaller in order to replenish many fished areas. Thus, there is a discord between the MPA network that would best achieve external replenishment and that which would maximize compliance. I investigated these competing criteria with a spatially structured model of a hypothetical marine fishery exploiting a sedentary reef-dwelling organism. With full compliance, a network of several small MPAs protects a population of similar size to that in a single large MPA and produces higher fishery yield across a range of fishing mortality rates. As noncompliance increases, however, the protected population in the network of several small MPAs approaches zero, whereas the single, large MPA population declines much less. Furthermore, at high levels of fishing mortality and noncompliance, yield with the network of several small MPAs begins to mirror that with no MPAs and drops below the yield with the single large MPA. Temporal variability in both the protected population size and yield are similar between the two designs with full compliance, but the single large MPA provides much greater stability in both metrics at high fishing mortality rates as noncompliance increases. My results highlight the important effects of noncompliance in realized MPA benefits and can explain why observed and expected effects might differ. Moreover, my results support a call for increased attention to rates of noncompliance and their ecological effects and greater collaboration among natural scientists, social scientists, managers, and stakeholders in understanding and altering illegal behavior.Efectos del Incumplimiento sobre elÉxito de Diseños Alternativos de Redes deÁreas Marinas Protegidas para Conservación y Gestión de Pesquerías Resumen: Los estudios que examinan la eficacia deáreas marinas protegidas (AMP) raramente consideran el potencial de incumplimiento. La violación de AMP típicamente ocurrirá cerca de los límites, por lo que las relaciones perímetro:área serán importantes en la determinación de la conservación actual, lo que sugiere que las AMP deben ser más grandes y posiblemente menos en número. Sin embargo, si la dispersión larvaria está muy localizada, las AMP deberán ser más numerosas, más dispersas y posiblemente más pequeñas para reestablecer muchasáreas pescadas. Por tanto, hay una discordancia entre la red de AMP que mejor logre el reestablecimiento externo y que maximice el cumplimiento. Investigué estos criterios en competencia con el modelo estructurado espacialmente de una pesquería marina hipotética que explota a un organismo arrecifal sedentario. Con cumplimiento total, una red de varias AMP pequeñas protege una ...

Ecological effects of marine protected areas on rocky reef communities—a continental-scale analysis

“…erences for changes within MPAs (Côté et al 2001, Eggleston & Parsons 2008 MPA design effects (1) Size of MPA (Kritzer 2004, Claudet et al 2008 (2) Source/sink dynamics associated with currents and proximity to adjacent MPAs (Crowder et al 2000, Carr et al 2003 (3) Porosity of protected area boundaries for species of interest, particularly whether preferred habitat extends continuously across boundary (Forcada et al 2008) cally survey marine communities. The project is based on the premises that: (1) when appropriately trained and resourced, the most enthusiastic and knowledgeable recreational divers can undertake routine investigation of the marine environment to a level equivalent to a professional scientific diver; and (2) a large proportion of the best recreational divers are willing to assist scientific studies, and will maintain long-term enthusiasm, if provided appropriate feedback, recognition and support to cover some costs of field activities.…”

“…(1) Pre-existing fishing effort, which affects the extent to which a site can potentially recover after fishing ceases (Lynch 2006) (2) Level of compliance of laws and regulations, and legal enforcement capacity (Kritzer 2004, Little et al 2005, Byers & Noonburg 2007, Guidetti et al 2008, Sethi & Hilborn 2008) (3) Management regulations, including whether fully or partially protected from fishing (Williams et al 2006, Lester & Halpern 2008) (4) Level of resource extraction of surrounding areas, which can affect spillover, and also affects changes at sites used as ref-…”

Challenging the win-win discourse on conservation and development: analyzing support for marine protected areas

“…In turn, empirical work has elucidated a link between levels of compliance or enforcement and various measures of MPA ecological success (Fig. 1, arrow b; Kritzer 2004, McClanahan et al 2006, McClanahan et al 2009). The buildup of biomass within well-managed MPAs is also found to enhance adjacent fisheries (Fig.…”

Pacific Canada’s Rockfish Conservation Areas: using Ostrom’s design principles to assess management effectiveness

“…Despite the high fecundity of many marine fishes, overfishing of target species can reduce populations and induce trophic cascades throughout marine ecosystems (Hutchings 2001, Pauly et al 2002, Hutchings and Reynolds 2004, Essington et al 2006, Branch et al 2010. In recent decades, marine conservation areas and other spatial management tools have become popular for conserving threatened marine populations (Kritzer 2004). When implemented in tandem with catch limitations and fishing fleet reductions, spatial management has been shown to effectively protect marine species and recover depleted populations (Allison et al 1998, Pauly et al 1998, Mosquera et al 2000, Halpern 2003, Babcock et al 2010).…”