The use of Local Ecological Knowledge as a complementary approach to understand the temporal and spatial patterns of fishery resources distribution

Abstract

BackgroundAcquiring fast and accurate information on ecological patterns of fishery resources is a basic first step for their management. However, some countries may lack the technical and/or the financial means to undergo traditional scientific samplings to get such information; therefore affordable and reliable alternatives need to be sought.MethodsWe compared two different approaches to identify occurrence patterns and catch for three main fish species caught with bottom-set gillnets used by artisanal fishers from northeast Brazil: (1) scientific on-board record data of small-scale fleet (n = 72 trips), and (2) interviews with small-scale fishers on Local Ecological Knowledge (LEK) (n = 32 interviews). We correlated (Pearson correlations) the months cited by fishers (LEK) as belonging to the rainy or to the dry season with observed periods of higher and lower precipitation (SK). The presence of the three main fish species at different depths was compared between LEK and SK by Spearman correlations. Spearman correlations were also used to compare the depths of greatest abundance (with the highest Capture per Unit Effort - CPUE) of these species; the CPUEs were descendly ordered.ResultsBoth methods provided similar and complementary bathymetric patterns of species occurrence and catch. The largest catches occured in deeper areas, which also happened to be less intensively fished. The preference for fishing in shallower and less productive areas was mostly due to environmental factors, such as weaker currents and less drifting algae at such depths.ConclusionBoth on-board and interview methods were accurate and brought complementary information, even though fishers provided faster data when compared to scientific on-board observations. When time and funding are not limited, integrative approaches such as the one presented here are likely the best option to obtain information, otherwise fishers’ LEK could be a better choice for when a compromise between speed, reliability and cost needs to be reached.Electronic supplementary materialThe online version of this article (doi:10.1186/s13002-017-0156-9) contains supplementary material, which is available to authorized users.

Fishers’ Local Ecological Knowledge (LEK) on Connectivity and Seascape Management

“…This indicates that, even though there was a significant difference found between the two different epistemological knowledge systems due to the different approaches of acquiring ecological knowledge, both LEK and CSK can be used to complement each other. This was in accordance with other studies comparing LEK and CSK on fish biology and ecology in Tanzania (Gaspare et al, 2015), Brazil (Silvano et al, 2006(Silvano et al, , 2010Silvano and Begossi, 2012;Begossi et al, 2016;Lima et al, 2017), and the Philippines (Selgrath et al, 2016). Multiple research papers advocate that local knowledge should be used in conjunction with scientific knowledge (Berkes et al, 2000;Johannes et al, 2000;Garcia-Quijano, 2015).…”

Integrating science and citizen science: the dusky grouper (Epinephelus marginatus) sustainable fishery of Copacabana, Rio de Janeiro, Brazil

“…Fishers are also shown to provide helpful information regarding the temporal abundance of fish and changes therein, based on CPUE [47] and regarding different fishers’ perceptions concerning MPAs. Other temporal changes were also detected by Lima et al [48] in the SE Atlantic Brazilian areas, such as a decrease in biomass of the fish caught and a higher abundance of relatively small fish.nats…”

The ability of artisanal fishers to recognize the dolphins they cooperate with

“…Long-term studies are particularly challenging when involving cetaceans, which are wideranging, deep-diving, and fast-moving animals [25]. In this context, traditional ecological knowledge can fill some of the gaps of scientific knowledge on the species, habitat, and ecosystems [26][27][28], enabling quick solutions for co-management and immediate conservation of ecological systems [29][30][31].…”

“…Fishers also fit into different socio-economic profiles: (a) the professionals-those who rely on the fishing activity as the main source of income; (b) the opportunists-those who tend to interact with dolphins only during the mullet season; (c) and the amateurs-those who engage in the fishing with dolphins all year long, but as a hobby, since their main source of income depends on other activities [22]. The analysis of traditional knowledge needs to account for such variability that likely affects the quality and accuracy of individual perceptions on their systems [22,28,34].…”