Fishers “local ecological knowledge” (LEK) can be used to reconstruct long-term trends of species that are at very low biomass due to overfishing. In this study, we used historical memories of Sicilian fishers to understand their perception of change in abundance of cartilaginous fish in the Strait of Sicily over the last decades. We conducted interviews with 27 retired fishers from Mazara del Vallo harbor (SW Sicily) working in demersal fisheries, using a pre-defined questionnaire with a series of open and fixed questions related to the abundance of sharks and rays. The questionnaire included specific questions about the trends they perceived in catch or by-catch of cartilaginous fish abundance between the 1940s and 2000s compared to the present. Information was gathered for 18 species, including Carcharhinidae, mesopredatory demersal sharks (Squalidae, Hexanchidae, Centrophoridae, Oxynotidae, Triakidae, Scyliorhinidae, and Squatinidae) and batoids. Overall shark catches were perceived to have diminished since the early 1940s: about 95% of fishers reported the decline of commercially important species (e.g., Mustelus spp.) and indicated species that could have been depleted or locally extinct (e.g., Squatina spp., Sphyrna lewini, Mustelus asterias, etc.). Our study shows that LEK of fishers can be beneficial for reconstructing long-term population trends of exploited species when traditional standard data on fisheries catch or species relative abundance from surveys is limited or only available for recent periods. The results obtained clearly indicate the rapid and alarming decline of elasmobranchs in the Strait of Sicily highlighting the need for urgent conservation measures to be adopted.
Local or Traditional Knowledge
There is a reluctance to incorporate Fishers’ Ecological Knowledge (FEK) into the evidence base used to underpin marine management decisions. FEK has proved to be useful as an alternative reference of biological changes in data-poor scenarios. Yet, recreational fisher knowledge has rarely been included in scientific studies despite being a source of FEK. Here, the use of recreational FEK to assess the conservation status of marine ecosystems in Galicia (NW Spain) was evaluated. Galicia has a highly complex marine socioecological system that includes both a large global commercial fleet and a powerful recreational sector, alongside other important stakeholders (e.g., tourism, aquaculture). Anglers and spear fishers were asked to provide their perceptions of the conservation status of fish stocks and the impacts on marine ecosystems. Face-to-face interviews were transcribed into text and analyzed using text mining tools. Key concepts were used to quantify fishers’ perceptions of changes in their target fish stocks and quantify the main impacts on marine ecosystems. Overfishing and habitat loss, followed by reduction in biodiversity, pollution, and warming temperatures were considered to be the main drivers of the poor status of cephalopods and finfish stocks. Perceived temporal declines in fish stocks were consistent with available biological data, highlighting the potential for recreational FEK to be used to assess long-term ecological changes. It was important to seek opinions from different users, including fishers from traditional commercial and recreational fisheries, as these groups had good knowledge of the impacts on natural and cultural community heritage. The poor status of ballan wrasse (Labrus bergylta) and kelp beds was identified, which was of concern due to it being a key species in coastal ecosystems. Use of FEK is a good approach to develop knowledge of these systems, but broader monitoring programs are needed to protect the future of these ecosystems.
Numerical modeling efforts in support of restoration and protection activities in coastal Louisiana have traditionally been conducted externally to any stakeholder engagement processes. This separation has resulted in planning- and project-level models built solely on technical observation and analysis of natural processes. Despite its scientific rigor, this process often fails to account for the knowledge, values, and experiences of local stakeholders that often contextualizes a modeled system. To bridge this gap, a team of natural and social scientists worked directly with local residents and resource users to develop a participatory modeling approach to collect and utilize local knowledge about the Breton Sound Estuary in southeast Louisiana, USA. Knowledge capture was facilitated through application of a local knowledge mapping methodology designed to catalog local understanding of current and historical conditions within the estuary and identify desired ecological and hydrologic end states. The results of the mapping endeavor informed modeling activities designed to assess the applicability of the identified restoration solutions. This effort was aimed at increasing stakeholder buy-in surrounding the utility of numerical models for planning and designing coastal protection and restoration projects and included an ancillary outcome aimed at elevating stakeholder empowerment regarding the design of nature-based restoration solutions and modeling scenarios. This intersection of traditional science and modeling activities with the collection and analysis of traditional ecological knowledge proved useful in elevating the confidence that community members had in modeled restoration outcomes.
A growing number of studies suggest a participatory ecosystem approach to support decision-making toward resilience and sustainability in social-ecological systems. Social-ecological resilience (SER) principles and practices are recommended to manage natural crises. However, it is necessary to broaden our understanding of SER on human-induced disturbances driven by economic development projects. In this paper we present the social-ecological system of Araçá Bay (Brazil), a small-scale fishery community that has experienced successive disturbances due to development projects since the 1930s. There was a lack of studies about the impacts of development projects in this bay. As part of a major project that aimed to build an ecosystem-based management plan for Araçá Bay through a participatory planning process, we focused on investigating fishers’ traditional ecological knowledge (TEK) to understand Araçá Bay’s small-scale fisheries social-ecological system. The objectives were to: (1) investigate fishers’ TEK regarding management practices and linked social mechanisms, human-induced disturbances and their consequences for the social-ecological system, ecosystem goods and services, and future threats; and (2) provide information based on TEK to the participatory planning process and analyze its contribution to Araçá Bay’s ecosystem-based management plan. Combined methods were used during 3 years of intense research-action (2014–2017): in-depth ethno-oceanographic interviews with expert fishers; monitoring Araçá Bay participatory meetings; and participant observation. Genuine local practices and social mechanisms from traditional culture were recorded, as well as TEK about 57 target fish species and methods to protect habitats and natural resources. Fishers also reported ecosystem disturbances and recovery processes. TEK was codified through SWOT analysis to assist the participatory planning process. Ecosystem services and threats based on TEK were brought to the participatory process, acknowledged by the participants, and incorporated into the management plan. TEK analysis proved to be an important methodology to provide historical environmental data regarding the impacts of development projects and support planning in disturbed ecosystems. In order to support coastal marine ecosystem-based management strategies toward SER and sustainability, researchers and practitioners should consider traditional territories in planning, recognize local practices and social mechanisms, and consider TEK on ecosystem goods and services and on historical human-induced disturbances.
One of the most pervasive signals of global climate change is altered patterns of distribution with trends towards poleward shifts of species. While habitat loss and destruction has severed connections between people and salmon in many locales, salmon fisheries in the high Arctic are just beginning to develop. To explore these emergent connections, we gathered local knowledge about Pacific salmon and emerging subsistence salmon fisheries in the Beaufort Sea region through ethnographic research in Utqiaġvik (formerly Barrow) and Nuiqsut, Alaska. Between 2010 and 2013, we interviewed 41 active fishermen and Elders who generally agreed that harvests of Pacific salmon species have been increasing in recent years, beginning in the 1990s and early 2000s. About 46% of active fishermen and Elders who discussed salmon abundance perceived an increasing trend over time. Another 43% characterized salmon abundance as cyclical or perceived no directional trend over time. The remaining fishermen (all from Nuiqsut) expressed their perception of decreasing salmon and fish abundance overall related to oil and gas development impacts to their local lands and waters. Given these mixed perceptions and harvests being an imperfect proxy for abundance, it remains unclear whether salmon populations are expanding in Arctic river systems. However, research participants have identified new stream systems not currently documented in the scientific literature where salmon are present and thought to be spawning. In both communities, we found that many fishermen and Elders often do not differentiate Pacific salmon species. Fishermen in both communities are developing new knowledge of salmon and increasing their use of salmon as a subsistence resource, yet uncertainties in the current data and local knowledge combine to generate equivocal evidence that salmon abundance is increasing. This lack of a clear increase in salmon abundance provides nuance to a simple story that warming has led to the increases of salmon in the Arctic. Despite the uncertainty regarding abundance, it is clear we are witnessing an emergence of new salmon fisheries in the high Arctic, perceived to be one among a suite of environmental and social changes currently being experienced in this region.
Mangroves, one of the major coastal ecosystems of tropical and subtropical regions, are critical habitats for fish and crustaceans, and provide a number of ecosystem services to people. While mangrove uses have been widely documented based on local ecological knowledge, seldom has this approach been used to analyse the mangrove-fishery relationship. By conducting semi-structured interviews (n = 82) with fishers in three different villages surrounding the Ciénaga Grande de Santa Marta, the most important lagoon system in the Colombian Caribbean because of its size and productivity, we evaluated fishing activity over time, mangrove use and mangrove-fishery linkage, and fishing and gear spatial distribution. Respondents believed that mangroves are critical habitats for fishery resources because they function as nurseries, food source and reproduction areas, and considered that the resource would be in jeopardy in the absence of mangroves. While fishing is the main activity in mangroves, they are also used for firewood, construction and to make fishing gear, but how fishers use mangroves varies across villages. Fishing is concentrated close to mangroves (<20 m) and fishers' villages though there was some gear and species-dependent spatial variation across villages. Given that the system is highly degraded and conservation and fishery management plans are urgently required, we suggest combining scientific with local ecological knowledge in the planning and implementation of restoration and conservation plans to increase the chances of such programs being successful.
Human impacts on the marine environment threaten the wellbeing of hundreds of millions of people. Marine environments are a common-pool resource (CPR) and one of their major management challenges is how to incorporate the value of ecosystem services to society in decision-making. Cultural ecosystem services (CES) relate to the often intangible benefits people receive from their interactions with the natural environment and contribute to individual and collective human wellbeing. Priority knowledge gaps include the need to better understand shared values regarding CES, and how to effectively integrate these values into decision-making. We filmed 40 Community Voice Method interviews with marine stakeholders in two areas of the UK to improve on the valuation of coastal and marine CES. Results show that cultural benefits including sense of place, aesthetic pleasure and cultural identity were bi-directional, contributed directly to a ‘fulfilled human life’ and were associated with charismatic marine life and biodiversity. Other-regarding self-transcendence values were salient underscoring a desire for sustainable marine management. We critically reflect on our analytical framework that integrates aspects of the UK National Ecosystem Assessment and IPBES conceptual frameworks. The thematic codebook developed for this study could prove useful for future comparative studies in other marine CES contexts. We propose that values-led management could increase the efficacy of marine planning strategies.
Fisher's knowledge offers a valuable source of information to run parallel to observed data and fill gaps in our scientific knowledge. In this study we demonstrate how fishers' knowledge of historical fishing effort was incorporated into an Ecopath with Ecosim (EwE) model of the Irish Sea to fill the significant gap in scientific knowledge prior to 2003. The Irish Sea model was fitted and results compared using fishing effort time-series based on: (i) scientific knowledge, (ii) fishers' knowledge, (iii) adjusted fishers' knowledge, and (iv) a combination of (i) and (iii), termed “hybrid knowledge.” The hybrid model produced the best overall statistical fit, capturing the biomass trends of commercially important stocks. Importantly, the hybrid model also replicated the increase in landings of groups such as “crabs & lobsters” and “epifauna” which were poorly simulated in scenario (i). Incorporating environmental drivers and adjusting vulnerabilities in the foraging arena further improved model fit, therefore the model shows that both fishing and the environment have historically influenced trends in finfish and shellfish stocks in the Irish Sea. The co-production of knowledge approach used here improved the accuracy of model simulations and may prove fundamental for developing ecosystem-based management advice in a global context.
Local ecological knowledge (LEK) of resource users is a valuable source of information about environmental trends and conditions. However, many factors influence how people perceive their environment and it may be important to identify sources of variation in LEK when using it to understand ecological change. This study examined variation in LEK arising from differences in people’s experience in the environment. From 2014 to 2016, we conducted 98 semi-structured interviews with subsistence fishers and recreational charter captains in four Alaskan coastal communities to document LEK of seven fish species. Fishers observed declines in fish abundance and body size, though the patterns varied among species, regions, and fishery sectors. Overall, subsistence harvesters provided a longer-term view of abundance changes compared with charter captains. Regression analyses indicated that the extent of people’s fishing areas and their years of fishing experience were relatively important factors in explaining variation in fishers’ perceptions of fish abundance. When taken together, perspectives from fishers in multiple regions and sectors can provide a more complete picture of changes in nearshore fish populations than any source alone. These findings underscore the importance of including people with different types of expertise in local knowledge studies designed to document environmental change.
Climate change and biological invasions are rapidly reshuffling species distribution, restructuring the biological communities of many ecosystems worldwide. Tracking these transformations in the marine environment is crucial, but our understanding of climate change effects and invasive species dynamics is often hampered by the practical challenge of surveying large geographical areas. Here, we focus on the Mediterranean Sea, a hot spot for climate change and biological invasions to investigate recent spatiotemporal changes in fish abundances and distribution. To this end, we accessed the local ecological knowledge (LEK) of small‐scale and recreational fishers, reconstructing the dynamics of fish perceived as “new” or increasing in different fishing areas. Over 500 fishers across 95 locations and nine different countries were interviewed, and semiquantitative information on yearly changes in species abundance was collected. Overall, 75 species were mentioned by the respondents, mostly warm‐adapted species of both native and exotic origin. Respondents belonging to the same biogeographic sectors described coherent spatial and temporal patterns, and gradients along latitudinal and longitudinal axes were revealed. This information provides a more complete understanding of the shifting distribution of Mediterranean fishes and it also demonstrates that adequately structured LEK methodology might be applied successfully beyond the local scale, across national borders and jurisdictions. Acknowledging this potential through macroregional coordination could pave the way for future large‐scale aggregations of individual observations, increasing our potential for integrated monitoring and conservation planning at the regional or even global level. This might help local communities to better understand, manage, and adapt to the ongoing biotic transformations driven by climate change and biological invaders.