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Cephalopods are harvested in increasingly large quantities but understanding how to control and manage their stocks, and tracking the routes of the consumption that exploits them, lag behind what has been developed for exploiting finfish. This review attempts to redress the imbalance by considering the status of the major cephalopod stock species and the traceability of cephalopod seafood along the trade value chain. It begins with a general overview of the most important exploited cephalopods, their stock status and their market. Four major cephalopod resources are identified: the three squid species Todarodes pacificus, Dosidicus gigas and Illex argentinus; and one species of octopus, Octopus vulgaris. The techniques and problems of stock assessment (to assess sustainability) are reviewed briefly and the problems and possible solutions for assessing benthic stock such as those of octopuses are considered. An example of a stock well managed in the long term is presented to illustrate the value of careful monitoring and management: the squid Doryteuthis gahi available in Falkland Islands waters. Issues surrounding identification, mislabelling and illegal, unreported and unregulated (IUU) fishing are then reviewed, followed by a discussion of approaches and techniques of traceability as applied to cephalopods. Finally, some of the mobile apps currently available and in development for tracking seafood are compared. This review concludes with observations on the necessity for the strengthening and international coordination of legislation, and more rigorous standards for seafood labelling and for taxonomic curation of DNA sequences available in public databases for use in seafood identification. [ABSTRACT FROM AUTHOR]

The extraction of total lipids and tocopherol compounds from Patagonian squid (Doriteuthis gahi) by-products (viscera, heads, skin, etc.), resulting from squid mantel commercialisation, was studied. An optimisation simplex-lattice design by employing low-toxicity solvents (ethanol, acetone, and ethyl acetate) was carried out taking into account their relative concentrations. The variance analysis of data showed that the quadratic model was statistically significant (p < 0.05); empirical coded equations were obtained as a function of the low-toxicity solvent ratios. The optimised lipid extraction was obtained by employing the 0.642/0.318/0.040 (ethanol/acetone/ethyl acetate) solvent ratio, respectively, leading to an 84% recovery of the total lipids extracted by the traditional procedure. In all extracting systems tested, the presence of α-, γ-, and δ-tocopherol compounds was detected, α-tocopherol being the most abundant. For α-, γ-, and δ-tocopherol compounds, the optimisation process showed that acetone extraction led to the highest concentrations in the lipid extract obtained (2736.5, 36.8, and 2.8 mg·kg−1 lipids, respectively). Taking into account the recovery yield on a by-product basis, the values obtained for the three tocopherols were included in the 88.0–97.7%, 80.0–95.0%, and 25–75% ranges, respectively, when compared to the traditional extraction. This study provides a novel and valuable possibility for α-tocopherol extraction from marine by-products. [ABSTRACT FROM AUTHOR]

The extraction of total lipids and tocopherol compounds from Patagonian squid (Doriteuthis gahi) by-products (viscera, heads, skin, etc.), resulting from squid mantel commercialisation, was studied. An optimisation simplex-lattice design by employing low-toxicity solvents (ethanol, acetone, and ethyl acetate) was carried out taking into account their relative concentrations. The variance analysis of data showed that the quadratic model was statistically significant (p < 0.05); empirical coded equations were obtained as a function of the low-toxicity solvent ratios. The optimised lipid extraction was obtained by employing the 0.642/0.318/0.040 (ethanol/acetone/ethyl acetate) solvent ratio, respectively, leading to an 84% recovery of the total lipids extracted by the traditional procedure. In all extracting systems tested, the presence of α-, γ-, and δ-tocopherol compounds was detected, α-tocopherol being the most abundant. For α-, γ-, and δ-tocopherol compounds, the optimisation process showed that acetone extraction led to the highest concentrations in the lipid extract obtained (2736.5, 36.8, and 2.8 mg·kg−1 lipids, respectively). Taking into account the recovery yield on a by-product basis, the values obtained for the three tocopherols were included in the 88.0–97.7%, 80.0–95.0%, and 25–75% ranges, respectively, when compared to the traditional extraction. This study provides a novel and valuable possibility for α-tocopherol extraction from marine by-products.

The Patagonian long-finned squid Doryteuthis gahi is an abundant commercial species within Falkland Island waters. The population consists of two temporally distinct spawning cohorts, inferred to have markedly different patterns of migration and timings of ontogenetic events. Ontogenetic migrations of each cohort were confirmed by analysis of the chemical composition of statoliths collected from both cohorts in two consecutive years. Trace element concentrations were quantified using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), to determine temporal and cohort-specific variation. Individual ablation craters, ablated in a transect from the nucleus to the rostrum edge, were aged to produce high-resolution elemental chronologies. Generalized additive mixed models (GAMM) indicated that cohort and life history stage had a significant effect on Sr/Ca and Ba/Ca ratios. Sr/Ca and Ba/Ca ratios were both negatively correlated with near-bottom water temperature, with Ba/Ca also potentially correlated to depth. Statolith elemental chronologies have useful applications as natural tags, discriminating between spawning cohorts. • Elemental chronologies of Ba and Sr were constructed for statoliths of Doryteuthis gahi using LA-ICP-MS. • Temporally distinct spawning cohorts had unique elemental chronologies. • Elemental chronologies displayed significant variation throughout ontogeny. • Cohort-specific chronologies were most dissimilar during 80–160 d post-hatching. • Sr/Ca and Ba/Ca ratios were both negatively correlated with near-bottom water temperature. [ABSTRACT FROM AUTHOR]

The Patagonian long-finned squid Doryteuthis gahi is an abundant commercial species within Falkland Island waters. The population consists of two temporally distinct spawning cohorts, inferred to have markedly different patterns of migration and timings of ontogenetic events. Ontogenetic migrations of each cohort were confirmed by analysis of the chemical composition of statoliths collected from both cohorts in two consecutive years. Trace element concentrations were quantified using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), to determine temporal and cohort-specific variation. Individual ablation craters, ablated in a transect from the nucleus to the rostrum edge, were aged to produce high-resolution elemental chronologies. Generalized additive mixed models (GAMM) indicated that cohort and life history stage had a significant effect on Sr/Ca and Ba/Ca ratios. Sr/Ca and Ba/Ca ratios were both negatively correlated with near-bottom water temperature, with Ba/Ca also potentially correlated to depth. Statolith elemental chronologies have useful applications as natural tags, discriminating between spawning cohorts. [ABSTRACT FROM AUTHOR]

Squid species are important components of the Southern Atlantic Ocean ecosystems, as they prey on a wide range of crustaceans, fish and cephalopods. As a result of this trophic interaction and their high abundance, they are considered reliable indicators of energy transfer and biomass in the food web. We identifiedIllex argentinus,Doryteuthis gahiandOnykia ingensas the most important squid species interacting on the Patagonian shelf, and used isotope analysis and stomach content identification to assess the feeding ecology and interaction of these squids in the ecosystem. Our results describe trophic interactions by direct predation ofO. ingensandI. argentinusonD. gahi, and a trophic overlap of the three squid, and indicate a higher trophic level and differences in the foraging areas for mature and maturingD. gahiinferred throughδ15N andδ13C concentrations. These differences were related to the segregation and different habitat of large matureD. gahiand suggest a food enrichment of C and N based on feeding sources other than those used by small maturingD. gahiandI. argentinusandO. ingens. [ABSTRACT FROM PUBLISHER]

Doryteuthis gahi squid stocks in the Falkland Islands are assessed by depletion models which may include in-season recruitment pulses. Occurrences of in-season recruitment pulses are inferred by sharp peaks in CPUE, but this ad hoc approach does not distinguish between true recruitments into the fishery and aggregations of squid already in situ. Data were therefore investigated from 13 fishing seasons in which true recruitments could be identified by changes in D. gahi size distributions, and related to environmental variables of sea wind, sea surface temperature, and geostrophic currents. Changes in size distributions showed 30% of CPUE peaks to be true recruitments. Recruitment peaks followed a significant parabolic relationship between east-west and north-south sea wind vectors. Recruitment peaks occurring under west sea winds were characterized by a positive correlation between west and north wind speeds. Recruitment peaks occurring under east sea winds were characterized by a positive correlation between east and north wind speeds. The wind speed criteria were used to classify CPUE peaks in all D. gahi fishing seasons from 2002 to 2012. Among winter seasons, D. gahi abundance estimates correlated best with CPUE when depletion models included all recruitment peaks. Among summer seasons, which are shorter, abundance estimates correlated best with CPUE when depletion models included only the last overall peak. We hypothesize that identifying recruitment peaks improves the accuracy of depletion models, but time series must be sufficiently long for multi-peak models to fit optimally. [ABSTRACT FROM AUTHOR]

Abstract: The stomach contents of three squids: 57 Doryteuthis gahi with mantle length (ML) ranging from 7.0 to 37.0cm, 75 Illex argentinus (21.0–32.8cm) and 116 Onykia ingens (19.9–39.3cm) from commercial catches on the outer Patagonian shelf grounds during autumn (March and April 2012) were examined to describe their diet and compare their trophic spectrum. D. gahi preyed on 12 different items, I. argentinus on 20 and O. ingens on 29. Prey diversity increased with the sizes of the squids. Along growth, D. gahi shifted from crustaceans, mainly euphausiids to fish (Salilota australis) and squid (D. gahi and Histioteuthis sp.). Small to mid-sized I. argentinus and O. ingens consumed mostly two fish, two squid species D. gahi and Histioteuthis atlantica, two crustaceans Munida gregaria and Munida subrugosa and the Chaetognatha Sagitta elegans. All the three species show a high prey overlapping at similar sizes: Squid of smaller size (5–15cm ML) fed mainly on crustaceans: D. gahi on euphausiids and squat lobsters (Munididae). Mid-sized squid fed mainly on fish, most frequently Gymnoscopelus sp. and S. australis, and larger I. argentinus and O. ingens fed mostly on squids, including cannibalism. The overlapping of the diet of similar sized squid was large suggesting all preys are abundant species in autumn in the water column in the Patagonian Shelf. [Copyright &y& Elsevier]

Abstract: Long-term investigations of three abundant nektonic squid species from the Southwest Atlantic, Illex argentinus, Doryteuthis gahi and Onykia ingens, permitted to estimate important population parameters including individual growth rates, duration of ontogenetic phases and mortalities. Using production model, the productivity of squid populations at different phases of their life cycle was assessed and the amount of biomass they convey between marine ecosystems as a result of their ontogenetic migrations was quantified. It was found that squid are major nutrient vectors and play a key role as transient ‘biological pumps’ linking spatially distinct marine ecosystems. I. argentinus has the largest impact in all three ecosystems it encounters due to its high abundance and productivity. The variable nature of squid populations increases the vulnerability of these biological conveyers to overfishing and environmental change. Failure of these critical biological pathways may induce irreversible long-term consequences for biodiversity, resource abundance and spatial availability in the world ocean. [Copyright &y& Elsevier]

The Falkland Islands fishing industry is unique, as 60-80% of its annual catch consists of two squid species, Illex argentinus and Doryteuthis gahi. Short annual life cycles make both species susceptible to intra-annual environmental changes, resulting in large biomass fluctuations that must be addressed in management of the stocks. In the D. gahi fishery, short chains of communication between science, management and industry allow effective cooperation in the interest of long-term sustainable exploitation. The industry is responsive to short-notice requests for in-season information about the fishery. Management takes into account both scientific advice and industry recommendations, through ongoing consultations before and during the fishing seasons. As a result of this cooperation, D. gahi is one of the best managed squid fisheries in the world with local fishing companies being amongst the largest and most profitable enterprises in the Falklands economy. The I. argentinus fishery has the same potential, but a further level of cooperative management is needed as this squid is a straddling stock between several countries and the high seas. Development of a regional fisheries management organization in the South Atlantic Ocean is required to control multilateral exploitation and ensure long-term sustainability of I. argentinus stocks. [ABSTRACT FROM AUTHOR]

The Falkland Islands fishing industry is unique, as 60-80% of its annual catch consists of two squid species, Illex argentinus and Doryteuthis gahi. Short annual life cycles make both species susceptible to intra-annual environmental changes, resulting in large biomass fluctuations that must be addressed in management of the stocks. In the D. gahi fishery, short chains of communication between science, management and industry allow effective cooperation in the interest of long-term sustainable exploitation. The industry is responsive to short-notice requests for in-season information about the fishery. Management takes into account both scientific advice and industry recommendations, through ongoing consultations before and during the fishing seasons. As a result of this cooperation, D. gahi is one of the best managed squid fisheries in the world with local fishing companies being amongst the largest and most profitable enterprises in the Falklands economy. The I. argentinus fishery has the same potential, but a further level of cooperative management is needed as this squid is a straddling stock between several countries and the high seas. Development of a regional fisheries management organization in the South Atlantic Ocean is required to control multilateral exploitation and ensure long-term sustainability of I. argentinus stocks. [ABSTRACT FROM AUTHOR]

Doryteuthis gahi is a small squid species that has a wide distribution in South America. This species is characterized by coastal and benthic spawning, and its ontogenetic vertical migration is associated with upwelling zones, features that may restrict its dispersal potential. It has also been proposed that populations of these neritic squid are structured by the influence of local processes which act as barriers to gene flow. Based on this background, we evaluate the geographical structure of genetic diversity in D. gahi along its distribution in the south-eastern Pacific Ocean. We used 116 COI mtDNA sequences of squid collected from different sites in Peru and Chile and calculated genetic diversity, the population structure index Fst, and performed analysis of spatial molecular variance and exact tests to detect differences among localities. To infer demographic history we carried out tests of neutrality and Bayesian skyline analysis. Although there was little molecular divergence between Peru and Chile, we detected a significant genetic differentiation of D. gahi along its geographical distribution. Squid from Chile showed higher genetic diversity than those of Peru and the results of the demographic inference analysis suggest that the population of Peru is experiencing or experienced in the recent past demographic expansion, a pattern that was not found in Chile. We think that the current genetic patterns are consequences of northward migrations in the glaciation periods and posterior re-colonization of southern Chile in the deglacial period. [ABSTRACT FROM PUBLISHER]

The article explores the trophic link in the transfer of adult tapeworms of species Clistobothrim cf. montaukensis and Dinobothrium sp. to porbeagle sharks Lamna nasus. The parasite material used by the authors in their study was from 11 porbeagle sharks with sizes ranging from 132-218 centimeters and with standard techniques, genomic DNA was extracted from the anterior of the strobila. They found that the squid Doryteuthis gahi is the carrier of the tapeworms that are infecting porbeagle sharks. They add that teleost Micromesistius australis Norman and Macruronus magellanicus are also other potential sources of the tapeworms.

A unique observation was made of the cold water squid Doryteuthis gahi spawning in Patagonian shelf waters near the Falkland Islands, South Atlantic. This represents the first recorded observation of spawning behaviour for this species. In contrast to other loliginids, which spawn in large mixed-sex aggregations, a solitary female was observed adding a single egg capsule to an existing egg mass on a kelp stipe, (Lessonia trabeculata). If this behaviour is characteristic for this species then it represents a departure from normal loliginid spawning behaviour and is in agreement with the observed absence of D. gahi aggregations over spawning grounds. [ABSTRACT FROM AUTHOR]

The Falkland Islands fishing industry is unique, as 60-80% of its annual catch consists of two squid species, Illex argentinus and Doryteuthis gahi. Short annual life cycles make both species susceptible to intra-annual environmental changes, resulting in large biomass fluctuations that must be addressed in management of the stocks. In the D. gahi fishery, short chains of communication between science, management and industry allow effective cooperation in the interest of long-term sustainable exploitation. The industry is responsive to short-notice requests for in-season information about the fishery. Management takes into account both scientific advice and industry recommendations, through ongoing consultations before and during the fishing seasons. As a result of this cooperation, D. gahi is one of the best managed squid fisheries in the world with local fishing companies being amongst the largest and most profitable enterprises in the Falklands economy. The I. argentinus fishery has the same potential, but a further level of cooperative management is needed as this squid is a straddling stock between several countries and the high seas. Development of a regional fisheries management organization in the South Atlantic Ocean is required to control multilateral exploitation and ensure long-term sustainability of I. argentinus stocks., (© 2013 The Authors. Journal of Fish Biology © 2013 The Fisheries Society of the British Isles.)