Managing Small-Scale Commercial Fisheries for Adaptive Capacity : Insights from Dynamic Social-Ecological Drivers of Change in Monterey Bay

Globally, small-scale fisheries are influenced by dynamic climate, governance, and market drivers, which present social and ecological challenges and opportunities. It is difficult to manage fisheries adaptively for fluctuating drivers, except to allow participants to shift effort among multiple fisheries. Adapting to changing conditions allows small-scale fishery participants to survive economic and environmental disturbances and benefit from optimal conditions. This study explores the relative influence of large-scale drivers on shifts in effort and outcomes among three closely linked fisheries in Monterey Bay since the Magnuson-Stevens Fisheries Conservation and Management Act of 1976. In this region, Pacific sardine (Sardinops sagax), northern anchovy (Engraulis mordax), and market squid (Loligo opalescens) fisheries comprise a tightly linked system where shifting focus among fisheries is a key element to adaptive capacity and reduced social and ecological vulnerability. Using a cluster analysis of landings, we identify four modes from 1974 to 2012 that are dominated (i.e., a given species accounting for the plurality of landings) by squid, sardine, anchovy, or lack any dominance, and seven points of transition among these periods. This approach enables us to determine which drivers are associated with each mode and each transition. Overall, we show that market and climate drivers are predominantly attributed to dominance transitions. Model selection of external drivers indicates that governance phases, reflected as perceived abundance, dictate long-term outcomes. Our findings suggest that globally, small-scale fishery managers should consider enabling shifts in effort among fisheries and retaining existing flexibility, as adaptive capacity is a critical determinant for social and ecological resilience

Aims of methods used.

<p>Aims of methods used.</p

Map of the Monterey Bay area.

<p>Map includes the three major ports: Santa Cruz, Moss Landing, and Monterey.</p

Timeline of dominance modes and transition points.

<p>Identified drivers most associated with each transition are listed accordingly.</p

Simpson Diversity Index of landings.

<p>Higher values indicate more evenness (less dominance) among fisheries landings, lower values indicate less evenness (greater dominance of a single fishery), based on pounds landed (CDFW Table 18PUB) at the three study ports combined. Dotted line represents average.</p

Key features of the commercial fisheries that comprise the interconnected Monterey Bay wetfish fisheries system.

<p>*Available permits does not indicate the number of vessels with landings as some permitted vessels may not participate in a given year. The number of market squid permits applies only to round haul (seine) vessels; light boat and brail vessel permits are issued separately.</p><p>Key features of the commercial fisheries that comprise the interconnected Monterey Bay wetfish fisheries system.</p

Dominance mode transition points.

<p>Proportional landings bubble plots showing dominance mode transition points for three of the seven transition years identified by the cluster analysis. Circle size is scaled to relative volume of landings (Data from Table18PUB CDFW). Darkest purple circles are sardine landings, lightest purple are anchovy landings. Gray arrows represent the movement of focus shifting from one fishery to the next.</p