Shifts in fisheries management: adapting to regime shifts

Abstract

For many years, fisheries management was based on optimizing yield and maintaining a target biomass, with little regard given to low-frequency environmental forcing. However, this policy was often unsuccessful. In the last two to three decades, fisheries science and management have undergone a shift towards balancing sustainable yield with conservation, with the goal of including ecosystem considerations in decision-making frameworks. Scientific understanding of low-frequency climate–ocean variability, which is manifested as ecosystem regime shifts and states, has led to attempts to incorporate these shifts and states into fisheries assessment and management. To date, operationalizing these attempts to provide tactical advice has met with limited success. We review efforts to incorporate regime shifts and states into the assessment and management of fisheries resources, propose directions for future investigation and outline a potential framework to include regime shifts and changes in ecosystem states into fisheries management.

Shifts in North Sea forage fish productivity and potential fisheries yield

“…With the growing interest in implementing ecosystem‐based fisheries management (Pikitch et al., ), the regime‐shift subject is gradually becoming an integral part of the scientific endeavours in fisheries biology and management (Anderson & Piatt, ; Barange et al., ; King et al., ). Several studies have argued that the North Sea underwent a major regime‐shift in the late 1980s, manifested first as changes in primary and secondary production (McQuatters‐Gollop et al., ; Reid et al., ).…”

“…However, based on the time series length presented here and the large inter‐annual fluctuations in weight‐at‐age and recruitment, that even after converting to 3 years running averages were still distinctive for some stocks, it cannot be concluded if an abrupt regime‐shift like transition from one state to another has truly taken place, or if the change we observed reflects climatic oscillations on a multidecadal time‐scale, as reported for anchovy‐sardine systems (Chavez et al., ). Such differentiation may, however, be worth pursuing in the future, as it would be a major asset in models of resource fluctuations and execution of ecosystem based management actions (King et al., ).…”

“…Changes in ecosystems are often gradual and smooth and follows, for example, large‐scale climatological fluctuations. However, sudden rapid changes are not uncommon (Scheffer, Carpenter, Foley, Folke, & Walker, ), and the detection of such shifts is pivotal in responsive ecosystem based management (Casini, Bartolino, Molinero, & Kornilovs, ; King, McFarlane, & Punt, ; Pikitch et al., ). In the North Sea, the zooplankton community underwent considerable changes in the late 1980s and early 1990s, with the decline of the subarctic calanoid copepod Calanus finmarchicus being one of the most well‐documented examples (Beaugrand, Brander, Lindley, Souissi, & Reid, ; Defriez, Sheppard, Reid, & Reuman, ; Pitois & Fox, ).…”

Fishing and environmental influences on estimates of unfished herbivorous fish biomass across the Hawaiian Archipelago

“…B unfished represents the expected biomass of a population or community that is not exploited (Hilborn & Walters 1992, Quinn & Deriso 1999. While there is strong evidence that environmental forcing can influence fish biomass in addition to fishing , the incorporation of environmental variability into estimates of unfished reference points and assessments of fisheries depletion have been limited (Haltuch et al 2009, King et al 2015. When studies have controlled for environmental influences on fish biomass, there were marked improvements in estimates of B unfished and detectability of fishing effects (Hamilton et al 2010, Caselle at al.…”

Importance of Consideration of Climate Change at Managing Fish Stocks: A Case of Northern Russian Fisheries

“…In fact, even if they believe that it is occurring, most people think climate change is going to affect us later, and thus there is no real urgency". Although there were some attempts to formally incorporate climatic parameters into population models, these attempts have so far not been successful (King et al 2015).…”