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Simple Summary: The artisanal octopus fishery is a great tradition and has a large economic impact in Northern Spain. Despite its importance, there is scarce genetic information for this exploited population. The uniqueness of an exploited population and the effects that exploitation may have on its long-term survival is essential information that can be obtained by studying the past and current spatial and temporal genetic patterns. The mitochondrial DNA is used here as a genetic tool to gain insight into Northeast Atlantic octopus populations and their evolutionary history. Although it is not sensitive enough to detect differences in nearby populations, it allows us to differentiate the two main lineages that originated during the Quaternary glaciations. One of the lineages is present exclusively in northern latitudes and the other mainly in the south, although, for the first time, its presence is demonstrated also in the north of the Iberian Peninsula. This implies a more continuous distribution than previously thought for this lineage. We also detect temporal changes in the distribution of the two lineages in contact zones. These changes seem to be associated with the effect of changing oceanographic conditions. Future studies on these associations could be of interest for fisheries in the scenario of global climate change. Octopus vulgaris is one of the most harvested octopus species in the world. In the Iberian Peninsula, there are several small-scale fisheries that have a long-term tradition of harvesting octopus. The Asturias fleet (in Northern Spain) has an internationally recognized MSC label for its exploitation. Of concern, genetic assessments of exploited stocks are currently scarce, which could prevent the implementation of adequate managing strategies. We use two mitochondrial regions (cytochrome oxidase subunit 1 and control region) to analyze the genetic status and evolutionary events that conditioned octopus populations' characteristics in the Northeastern Atlantic. A total of 90 individuals were sampled from three different localities in the Iberian Peninsula as well as a location in Macaronesia. Temporal genetic analyses on Asturias and Algarve populations were also performed. Results indicated the absence of fine spatial genetic structuring but showed the Canary Islands (in Macaronesia) as the most distinct population. Our analyses detected two distinct clades, already described in the literature, but, for the first time, we confirmed the presence of the α-southern haplogroup in the Northern Iberian Peninsula. This result indicates a more continuous cline for the distribution of these two haplogroups than previously reported. Temporal changes in the distribution of both haplogroups in contact zones were also detected. [ABSTRACT FROM AUTHOR]

Octopus vulgaris (Cuvier, 1797) is a cephalopod species with great economic value. In western Asturias (northwest of Spain), O. vulgaris artisanal fisheries are relatively well monitored and conditionally eco-labeled by the Marine Stewardship Council (MSC). Despite this, the Asturian octopus stocks have not been genetically assessed so far. In order to improve the current fishery plan and contrast the octopus eco-label validity in Asturias, 539 individuals from five regions of the O. vulgaris geographic distribution, including temporal samplings in Asturias, were collected and genotyped at thirteen microsatellite loci. All the samples under analysis were in agreement with Hardy–Weinberg expectations. Spatial levels of genetic differentiation were estimated using F-statistics, multidimensional scaling, and Bayesian analyses. Results suggested that the O. vulgaris consists of at least four genetically different stocks coming from two ancestral lineages. In addition, temporal analyses showed stability in terms of genetic variation and high NE (> 50) for several generations in different localities within Asturias, pointing out to indeed sustainable fishery exploitation levels. Even though, the current Asturias fishery plan shows no significant genetic damages to the stocks, the regional-specific management plans need systematic genetic monitoring schemes as part of an efficient and preventive regional fishery regulation strategy. [ABSTRACT FROM AUTHOR]

We developed a new type of generalized depletion model adapted to the rapid life cycle of Octopus vulgaris and the data collection framework put in place in its co-managed small-scale fishery (SSF) in Asturias, northwest Spain. The model uses weekly data from 19 seasons to estimate annual recruitment and female spawners emigration out of the vulnerable stock to attend to their broods. The matched annual spawners-recruitment (SR) magnitudes are then used as observations in a non-Bayesian hierarchical inference framework. The Shepherd SR model was selected among three alternatives. The stock has a high degree of density-dependence, leading to overcompensation. The estimated SR model has an unstable equilibrium point, driving the stock to deterministic cyclic fluctuations under small disturbances. Under those conditions the maximum sustainable yield (MSY) is not applicable, lending further credence to Sidney Holt's opposition to the MSY as a basis for the elaboration of fishery management objectives, with potentially wide relevance to the management of SSF and cephalopod fisheries. We argue that harvest rates based on mean latent productivity, a concept that includes the MSY as a special case, are more adequate and sustainable for fluctuating stocks. [ABSTRACT FROM AUTHOR]

Abstract: Common octopus, Octopus vulgaris Cuvier, 1797, management in the west of Asturias has been carried out as a co-management experience since 2001. It includes the establishment of a closed season, a minimum capture weight of 1000g and the limitation of traps as the only authorized fishing gear. An assessment of these management rules is made in the present study. The percentage of mature females weighing between 900 and 1900g during the period of maximum reproductive development (February–June) is between 73% and 100% by 100g size class. Consequently, a minimum capture weight of 1000g can be considered adequate for the rational exploitation of this resource. Moreover, the constant monitoring of O. vulgaris landings (weight distribution and sex ratio) could be useful to find an indicator to permit the detection of changes in the spawning period, allowing managers to establish the closed season in the most suitable period in order to protect the recruitment of the next cohort. [Copyright &y& Elsevier]

Eco-labelling is gaining great international importance as a way to promote sustainable fisheries driven by the increasing demand for eco-certified products. Since 2016, the artisanal fleet to fish common octopus (Octopus vulgaris) of Navia-Porcía (Asturias, Spain) is certified by the Marine Stewardship Council (MSC), being the first octopus fishery certified by MSC in the world. Even though there is an ample evidence that confirms the existence of price premiums for seafood products with eco-labels in the retail market, there is still little research demonstrating the existence and the extent of price premiums at the producer or fisher's level, specifically from small-scale or artisanal fleets. The aim of this research is, therefore, to test the existence of a price premium for the artisanal fishers of MSC-certified common octopus from Asturias as well as to estimate the value of this premium. To carry out this analysis, we have applied the difference-in-difference (DiD) method using a panel of prices and quantities of common octopus sold at ports of the Spanish region of Asturias from 2010 to 2019. Our results confirm the existence of a price premium, between a 15.2% and a 24.6% over the uncertified octopus' price, that is paid to Asturian fishers who fish and sell the MSC-certified product. Thus, this paper provides evidence about the economic benefits of environmental certifications for small-scale and artisanal fleets to compensate the certification costs and promote sustainable fishing practices. • We have found evidence of a positive effect of the MSC certification on common octopus' prices in Asturian ports. • Eco-labelling allows to fishers to obtain a higher price to compensate the costs of environmental care practices and their certification. • Eco-labelling can be used to differentiate fish and seafood from small-scale and artisanal fleets. • Cooperation among different local agents to implement eco-labelling schemes can provide benefits for coastal communities. [ABSTRACT FROM AUTHOR]