A social–ecological study of stock structure and fleet dynamics in the Newfoundland herring fishery

ICES Journal of Marine Science (2018), 75(1), 257–269. doi:10.1093/icesjms/fsx097 Original Article Barbara Paterson1,2,*, Barbara Neis3, and Robert L. Stephenson4,5 1 School of the Environment, Department of Environmental Science, Saint Mary’s University, NS, Canada, B3H 3C3 Marine Research Institute, Department of Biological Sciences, University of Cape Town, Rondebosch 7701, South Africa 3 Department of Sociology, Memorial University, St. John’s, NL, Canada A1C 5S7 4 Canadian Fisheries Research Network, University of New Brunswick, Fredericton, NB E3B 5A3, Canada 5 Fisheries and Oceans, St. Andrews Biological Station, St. Andrews NB E5B 2L9, Canada 2 *Corresponding author: tel: þ 1 902 491 6406; fax: þ 1 902 491 6406; e-mail: Paterson, B., Neis, B., and Stephenson, R. L. 2017. A social–ecological study of stock structure and fleet dynamics in the Newfoundland herring fishery. – ICES Journal of Marine Science, 75: 257–269. Received 20 June 2016; revised 29 March 2017; accepted 30 March 2017; advance access publication 1 June 2017. Successful management of small pelagic fisheries is critical in integrated ecosystem based approaches and requires understanding of how the ecological dynamics of pelagic stocks mesh with the economic and social dynamics of commercial fisheries and the larger systems within which they operate. Combining insights from stock assessments with those from local fishers, scientists, and managers, can help identify knowledge gaps that could jeopardize stock resilience. This article presents results from a social-ecological, mixed-methods study that combines insights from science and from interviews with fishermen, scientists, and managers of small pelagic fisheries in western Newfoundland, Canada (NAFO division 4R) and in NAFO division 4X. Different approaches to herring management are used in the two areas. In area 4R fishing for herring (Clupea harengus) is part of a complex multi-species, multi-gear fishery; most harvesters who target herring also target Atlantic mackerel (Scomber scombrus). Harvester interviews indicate herring in 4R, like herring in 4X and elsewhere, have substantial within-species stock structure, but that it is not well-documented in science and not well protected under the current management system. Further, fishing strategies in the competitive mackerel fishery in which the herring vessels are involved may contribute to the risk of over-fishing on some herring populations. Keywords: Atlantic herring (Clupea harengus), fishermen’s ecological knowledge, social-ecological analysis, stock structure. Introduction Small pelagic fish species play a key role in marine ecosystems as forage for marine mammals, birds, and other fish; they are also important contributors to the economies and food security of coastal nations. Small pelagic species account for up to 50% of global annual landings (Fréon et al., 2005). The combined effects of high fishing mortalities, past overfishing and the impacts of climate change are exerting pressure on small pelagic stocks in many parts of the world (Naylor et al., 2000; Barange et al., 2008; Melvin et al., 2009). Successful management of small pelagic fisheries is critical because of the ecological, social, and economic importance of small pelagic fish and because of their vulnerability to environmental factors and to overfishing. In line with commitments to ecosystem-based management, fisheries management objectives in Canada and elsewhere have broadened in recent years to include productivity, biodiversity and habitat considerations (Gavaris, 2009). Within the biodiversity category, increasing attention is being given to within-species diversity, i.e. stock structure. Herring stocks have a complex population structure; they are made up of several distinct spawning units, which may mix at various times during their life history (Stephenson et al., 2009). Herring stock structure has been discussed for more than a century (Iles and Sinclair, 1982; Sinclair and Solemdal, 1988; Stephenson and Clark, 2002; Sinclair, 2009). The biological basis for the notion of herring stock-complexes is well documented and based inter alia on observations that C International Council for the Exploration of the Sea 2017. All rights reserved. V For Permissions, please email: A social–ecological study of stock structure and fleet dynamics in the Newfoundland herring fishery 258 B. Paterson et al. herring spawn in multiple, discreet locations within a stock distribution area, that herring return to the same spawning grounds from which they originated (“homing”), and that different subpopulations show different trends in abundance and growth (Stephenson et al., 2009; Payne, 2010). Management based on preserving this complex population structure has the potential to reduce the vulnerability of herring stocks to overfishing and ecosystem change. There is ongoing debate, however, whether it is practical to manage at the scale of individual spawning aggregations (Stephenson, 2002; Kell et al., 2009). This article reports findings from a study of the herring fishery in area 4R on the west coast of Newfoundland, Canada. In Canadian waters, the distribution of Atlantic herring extends from Georges Bank and the Nova Scotia coast to Newfoundland and Labrador (DFO, 2010a) (Figure 1). In eastern Canada, a great deal of attention has been paid to the collapse of multiple groundfish stocks in the early 1990s and to their limited recovery more than 20 years later (Frank et al., 2005). The collapse of Atlantic herring (Clupea harengus harengus) on Georges Bank in the 1960s (Melvin and Stephenson, 2007) and the current weak status of the Atlantic herring and capelin (Mallotus villosus) stocks in the region (DFO, 2012a) have received less attention. These species are the prey for cod and other groundfish (FRCC, 2009). Like all small pelagic fish, Atlantic herring populations are highly vulnerable to ecosystem changes and prone to rapid changes in abundance and collapse (Stephenson, 1997). Herring stocks in 4R are considered to be in trouble (DFO, 2014). A multidisciplinary research programme (www.curra.ca) took place on the west coast of Newfoundland between 2007 and 2014. Participating researchers observed intensive herring and mackerel purse seine fisheries each fall in the region and heard local people express concerns about the effect of these intensive, localized fisheries on the herring stocks in the region. We designed a study with the following objectives: (i) to gain a clearer picture of herring management in the region by interviewing fishermen, processors, scientists and managers and comparing the management in 4R with the more collaborative approach in the Bay of Fundy (Stephenson et al., 1999; Power et al., 2011), NAFO area 4X (Figure 1); and, (ii) to identify potential gaps in scientific knowledge and management that could jeopardize stock resilience by comparing available scientific information, such as landings data a (...truncated)