Assessing the sustainability and adaptive capacity of the gooseneck barnacle co-management system in Asturias, N. Spain

Influence of a changing wave climate on the quality and morphometry of the stalked barnacle Pollicipes pollicipes (Gmelin, 1789), along the coasts of NW Iberia

Wave climate is shifting over the last decades along the Atlantic coasts of Europe ultimately driven by large-scale patterns of atmospheric variability forced by anthropogenic global warming. Changes in wave height and surf zone orbital currents are hypothesized to drive marked shifts in the shape of intertidal organisms such as the stalked barnacle Pollicipes pollicipes, whose quality and market price are known to decrease non linearly with the peduncle length: width ratio S. This study evaluates wave trends in NW Iberian Peninsula, using the Spanish Port System 2006-2020 SIMAR wave hindcast. On the other hand, trends in stalked barnacle morphology and quality are estimated from 26 sites at the management regions of Baiona and A Guarda between 2011 and 2020. Results show evidence of temporal changes in barnacle quality and, especially, morphometry caused by simultaneous shifts in winter wave induced orbital currents. Because of the non linear relationship between S and the high quality threshold, large increases in S are usually translated to small reductions in quality. However, we identified a tipping point around S = 2.4 that if surpassed can lead to great drops in barnacle quality. In addition, changes in wave forcing will have different effects at each extraction site, as trends in wave climate are decoupled from barnacle morphometry at steeper sites sheltered from the predominant wave direction. In conclusion, this knowledge could be applied to develop site specific barnacle harvesting strategies based on annual wave climate forecasts.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s11160-024-09838-2.

Social attributes can drive or deter the sustainability of bottom-up management systems

Despite the growing popularity of bottom-up fishery management schemes not all socio-ecological systems respond well to this approach. Unfortunately, due to the heterogeneous nature of socio-ecological systems and lack of long-term, place-based studies we have yet to disentangle the impact of social attributes on their sustainability. The gooseneck barnacle fishery in Asturias, a fishery with a long-standing tradition of bottom-up management schemes and a plethora of spatially explicit data, provides a unique opportunity to test the effect of social attributes on 7, heterogeneous, co-managed, Territorial Use Rights for Fishing (TURFs) areas. We developed an integrated index that reflects the sustainability of each individual Asturian TURF on 2 key spheres of the total environment: biosphere and anthroposphere. Additionally, we carried out detailed surveys to assess both user and governance social attributes in each TURF. The effect of these attributes on the sustainability index was assessed using Linear Regression Analysis, One Way Analysis of Variance and Analysis of Covariance. According to our results, social factors are key drivers for the sustainability of a bottom-up management system. Additionally, bottom-up management schemes promote strong governance social attributes but can be systematically weakened if user-defined social attributes are lacking. Fortunately, user-defined attributes tend to be linked and can have a compensating effect, as was the case in Asturias were conflict resolution mechanisms and strong leadership were able to compensate for low cooperation within the TURFs. Thus, social attributes must be considered when assessing the suitability or sustainability of bottom-up management schemes.

Exploring determinants for the implementation of mixed TURF-aquaculture systems

Territorial use rights in fisheries (TURFs) have been highlighted as a means to deter the race for fish. Nevertheless, in many situations TURFs are not able to meet all their goals, jeopardizing their continuity. Here we explore one of several innovations on TURFs, mixed TURF-aquaculture systems, which can help overcome the challenges of maintaining sustainable socio-ecological systems. We analyzed the history of mixed TURF and small-scale aquaculture systems in Chile, particularly 8 recent learning platforms in the Coquimbo region. Additionally, we assessed the impact of 6 variables, from multiple spheres, on the implementation of mixed TURF-aquaculture systems. Despite low values in several variables, 75% of the learning platforms managed to implement aquaculture systems and 38% have been successful in developing monitoring efforts. Social capital was key in the implementation of the mixed systems. By investing in social capital policy makers can contribute to the successful implementation of mixed TURF-aquaculture systems, thus promoting a livelihood diversification strategy for fishing communities that encompasses the economic benefits of aquaculture with the socio-ecological benefits of TURFs. However, their development and enabling conditions must be monitored to embrace their synergies.

Fisheries regulatory regimes and resilience to climate change

Climate change is already producing ecological, social, and economic impacts on fisheries, and these effects are expected to increase in frequency and magnitude in the future. Fisheries governance and regulations can alter socio-ecological resilience to climate change impacts via harvest control rules and incentives driving fisher behavior, yet there are no syntheses or conceptual frameworks for examining how institutions and their regulatory approaches can alter fisheries resilience to climate change. We identify nine key climate resilience criteria for fisheries socio-ecological systems (SES), defining resilience as the ability of the coupled system of interacting social and ecological components (i.e., the SES) to absorb change while avoiding transformation into a different undesirable state. We then evaluate the capacity of four fisheries regulatory systems that vary in their degree of property rights, including open access, limited entry, and two types of rights-based management, to increase or inhibit resilience. Our exploratory assessment of evidence in the literature suggests that these regulatory regimes vary widely in their ability to promote resilient fisheries, with rights-based approaches appearing to offer more resilience benefits in many cases, but detailed characteristics of the regulatory instruments are fundamental.

Crossing Science-Policy-Societal Boundaries to Reduce Scientific and Institutional Uncertainty in Small-Scale Fisheries

The governance of small-scale fisheries (SSF) is challenging due to the uncertainty, complexity, and interconnectedness of social, political, ecological, and economical processes. Conventional SSF management has focused on a centralized and top-down approach. A major criticism of conventional management is the over-reliance on 'expert science' to guide decision-making and poor consideration of fishers' contextually rich knowledge. That is thought to exacerbate the already low governance potential of SSF. Integrating scientific knowledge with fishers' knowledge is increasingly popular and is often assumed to help reduce levels of biophysical and institutional uncertainties. Many projects aimed at encouraging knowledge integration have, however, been unsuccessful. Our objective in this research was to assess factors that influence knowledge integration and the uptake of integrated knowledge into policy-making. We report results from 54 semi-structured interviews with SSF researchers and practitioners from around the globe. Our analysis is framed in terms of scientific credibility, societal legitimacy, and policy saliency, and we discuss cases that have been partially or fully successful in reducing uncertainty via push-and-pull-oriented boundary crossing initiatives. Our findings suggest that two important factors affect the science-policy-societal boundary: a lack of consensus among stakeholders about what constitutes credible knowledge and institutional uncertainty resulting from shifting policies and leadership change. A lack of training for scientific leaders and an apparent 'shelf-life' for community organizations highlight the importance of ongoing institutional support for knowledge integration projects. Institutional support may be enhanced through such investments, such as capacity building and specialized platforms for knowledge integration.