Size matters: fishing less and yielding more in smaller-scale fisheries

Several factors influence catches and the sustainability of fisheries, and such factors might be different depending on the scale on which fisheries work. We investigated the existence of possible subdivisions within small-scale fisheries (SSF) themselves, regarding their economic performance and relative social and environmental impacts to understand which categories of these two types of fleets are best positioned to support sustainability. By doing so, we investigated if it is a good strategy for SSF to aim to grow towards larger scales. We obtained economic and ecological data from landing samplings and information on technological efficiency of this fleet, using a northeastern Brazilian state as a case study. We defined a cut-off point to separate the SSF into two categories of boats, according to their size and gear. We compared their cpue and the factors affecting it within each category; we also compared economic (number of boats, number of landings, jobs, gears, catch, travel time and total time of the fishery, revenues, costs, profits, revenue per unit of effort, and profit per unit of effort) and ecological factors (vulnerability of species caught) between the two categories. We found that small boats spent less time fishing and employed comparatively more people per landed value and catch. The cpue and profits of small boats were also higher. Both large and small boats exploit species with the same overall vulnerability. Therefore, being smaller, even within the SSF category, seems to be a more advantageous social and economic strategy for guaranteeing higher catches and more employment opportunities per catch. These findings need to be taken into account when defining new policies, such as the distribution of subsidies that support or not the sustainable use of fishery resources

Resilience and Social Adaptation to Climate Change Impacts in Small-Scale Fisheries

[Abstract] Small-cale fisheries are important for livelihoods, food security, jobs and income worldwide. However, they face major challenges, including the increasing effects of climate change that pose serious risks to coastal ecosystems and fishing communities. Although scientific research on climate change impacts has increased in recent years, few studies have explored the social impacts on small-scale fisheries. Using Galicia (Spain) as a case study, we investigated individual and household-level adaptive responses to climate change among fishers in three fishing guilds (Cambados, Campelo, and Redondela). Specifically, we estimated the economic vulnerability of shellfishers and assessed the diversity of social adaptive responses used to deal with climate change. Although fishers’ income strongly depends on shellfishing in all studied areas, our findings show that less fishing experience and lower engagement in fisher associations tend to increase the economic vulnerability of the fishers. The fishers’ vulnerability decreases as the size of households increases, while fishers who pay a mortgage and who live in households with fewer active members tend to be more vulnerable. The findings also show that Galician shellfishers have developed a wide range of adaptation strategies to anticipate and respond to climate change impacts, namely harvesting pricier and more abundant species, reducing household expenses and increasing social involvement in shellfishery associations. Although the adaptive strategies have helped Galician fishers to deal with climate change impacts, several threats to the sustainability of shellfisheries remain, such as a decrease in the abundance of key native shellfish species, and a high dependence on public and private aid to ensure reasonable incomes for shellfisheries. These findings are of interest and relevance to other similar small-scale fisheries around the world facing similar climate change challenges.This research was supported by grants CTM2014- 51935-R from the Spanish Ministerio de Economía y Competitividad to the project MARISCO and the Autonomous government Xunta de Galicia-FEDER (projects GRC2013-004, ED431C 2017/46). SV and PP acknowledge funding from the Xunta de Galicia (RECREGES II project under Grant 1400 ED481B2018/017, and Grupo de Referencia Competitiva GI-2060 AEMI, under Grant 1401 ED431C2019/11), the H2020–European Commission project Atlantic ECOsystems assessment, forecasting & sustainability (AtlantECO, ref. 2019-PI022). SV thanks the financial support for the EQUALSEA project ERC Consolidator, under Grant Agreement n°101002784 funded by the European Research Council. GM was supported by post-doctoral contracts from projects MARISCO and PERCEBES (BiodivERsA COFUND & Spanish Agencia Estatal de Investigación; PCIN-2016-063)Xunta de Galicia; GRC2013-004Xunta de Galicia; ED431C 2017/46Xunta de Galicia; ED481B2018/017Xunta de Galicia; ED431C2019/1

Co-management of culturally important species:A tool to promote biodiversity conservation and human well-being

Co-management has been advocated as an effective tool to achieve natural resource conservation worldwide. Yet, the potential of co-management arrangements can fail to be realized when there is insufficient local engagement. In this perspective paper, we argue that co-management schemes focusing on culturally important species (CIS) can help overcome this issue by engaging local people's interest. To develop this theory, we explore published data on the outcomes of two management schemes, both encompassing multiple independent initiatives, to discuss CIS-management effects and benefits. We also show a compilation of CIS examples throughout the world and discuss the potential of CIS-management to reach a global audience. Based on these data, we argue that CIS-management can be an effective tool to reconcile the often intractable goals of biodiversity conservation and human welfare

Expression profile of genes associated with mastitis in dairy cattle

In order to characterize the expression of genes associated with immune response mechanisms to mastitis, we quantified the relative expression of the IL-2, IL-4, IL-6, IL-8, IL-10, IFN-γ and TNF- α genes in milk cells of healthy cows and cows with clinical mastitis. Total RNA was extracted from milk cells of six Black and White Holstein (BW) cows and six Gyr cows, including three animals with and three without mastitis per breed. Gene expression was analyzed by real-time PCR. IL-10 gene expression was higher in the group of BW and Gyr cows with mastitis compared to animals free of infection from both breeds (p < 0.05). It was also higher in BW Holstein animals with clinical mastitis (p < 0.001), but it was not significant when Gyr cows with and without mastitis were compared (0.05 < p < 0.10). Among healthy cows, BW Holstein animals tended to present a higher expression of all genes studied, with a significant difference for the IL-2 and IFN- γ genes (p < 0.001). For animals with mastitis no significant difference in gene expression was observed between the two breeds. These findings suggest that animals with mastitis develop a preferentially cell-mediated immune response. Further studies including larger samples are necessary to better characterize the gene expression profile in cows with mastitis

Climate change can reduce shrimp catches in equatorial Brazil.

Shrimps are an important and valuable fishing resource, being increasingly exploited worldwide, demanding appropriate management. However, factors such as how shrimps are affected by environmental variables and how such variables are likely to change under a climate change scenario are still poorly known. We used a Brazilian database with 10 years of shrimp catch and effort data, from 20 different small-scale equatorial fishing ports, to test how shrimp fishing productivity is affected by environmental (sea surface temperature (SST), wind, precipitation, and cloudiness), economic (ex-vessel price), spatial (fishing port), and temporal factors (year and month). The results showed that better productivities are reached at higher SST (to a limit 26 °C) and precipitation. Time (year) and space (different fishing villages showed different fishing success) also affected the fishing success. Considering that both temperature and precipitation were important determinants of shrimp productivity, we estimated how such productivity would be affected by climate change. Our results suggest that these fisheries could collapse in a warmer and drier future, which is a possible scenario for the region. Overall, a better understanding of regional shrimp fisheries could permit the development of tailor-made management measures. Besides, this study also shows how an economically important invertebrate stock is sensitive to climate change, which is a warning signal to developing countries, where there is a significant parcel of its population directly dependent on fishery exploitation

Modeling sensitive parrotfish (Labridae: Scarini) habitats along the Brazilian coast

In coral reef environments, there is an increasing concern over parrotfish (Labridae: Scarini) due to their rising exploitation by commercial small-scale fisheries, which is leading to significant changes in the reefs' community structure. Three species, Scarus trispinosus (Valenciennes, 1840), Sparisoma frondosum (Agassiz, 1831) and Sparisoma axillare (Steindachner, 1878), currently labeled as threatened, have been intensively targeted in Brazil, mostly on the northeastern coast. Despite their economic importance, ecological interest and worrisome conservation status, not much is known about which variables determine their occurrence. In this study, we adopted a hierarchical Bayesian spatial–temporal approach to map the distribution of these three species along the Brazilian coast, using landing data from three different gears (gillnets, spear guns, and handlines) and environmental variables (bathymetry, shore distance, seabed slope, Sea Surface Temperature and Net Primary Productivity). Our results identify sensitive habitats for parrotfish along the Brazilian coast that would be more suitable to the implementation of spatial–temporal closure measures, which along with the social component fishers could benefit the management and conservation of these species

Assessing drivers of tropical and subtropical marine fish collapses of Brazilian Exclusive Economic Zone

11 pages, 4 figures, 2 tables, supplementary data https://doi.org/10.1016/j.scitotenv.2019.134940Overfishing is a concerning threat that can lead to the collapse of fish stocks. We assessed the combinations of factors, including biological traits, types of exploitation and responses to sea temperature and salinity changes, that drive species to collapse in the Brazilian Exclusive Economic Zone (EEZ) tropical and subtropical regions. We applied a catch-based method of stock classification and a catch time series of 61 years from 132 exploited fish species. Species were categorized as Collapsed, Overexploited, Fully Exploited or in Development, and we used a GAM analysis to understand their categorization over time. Furthermore, a Redundancy Analysis was developed to assess the species characteristics that best predicted each exploitation category. Twelve species were classified as Collapsed, 55 as Overexploited, 46 as Fully Exploited and 19 as in Development. Tropical and subtropical exploited species collapses in Brazil were best explained by a complex combination of a negative impact of warmer sea temperatures, fishery exploitation and specific life-history traits. A synergistic interaction between these factors could bring species to collapse. We hypothesize that the exploitation of species with vulnerable traits may alter how these species respond to temperature and, therefore, lead them to collapse given that intense exploitation may affect their ability to respond to temperature increases. Measures to mitigate climate change impacts should take into consideration incentives to decrease the exploitation of vulnerable species and, specifically, consider species with more sensitive biological traits. Such measures are also important to minimize the socioeconomic impacts on the people that depend on these speciesJTV was funded by CAPES with a PhD scholarship. PFML thanks CNPq for a productivity grant. We also thank the Graduate Program in Ecology at UFRN for the infrastructural support. This study was partially financed by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) – Finance Code 001With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI