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Oceanographic parameters associated with spatial occurrence of cephalopods in standardized demersal fishing trawls in the NE AtlanticNARA Subscribed
In this work, the environmental occurrence ranges of different European cephalopod species are described for the whole NE Atlantic shelf including the greater North Sea and Baltic Sea. This is done based on the environmental parameters collected in-situ during surveys that caught commercially important cephalopod species (1990–2022). Results are supplemented and compared with information available in the published literature a...
The English Channel has the highest long-finned squid landings in the Northeast Atlantic, making squid one of the most valuable resources exploited by demersal fisheries operating in this area. This resource consists of two short-lived long-finned squid species: Loligo forbesii and L. vulgaris , which have a similar appearance (they are not distinguished by fishers) but differ in the timing of their life cycle: in L. forbesii...
Cetaceans of north-western continental Africa (Morocco to Liberia): diversity and distributionOA Marine
The north-western coast of Africa is one of the most productive marine systems in the world, where a high diversity of cetacean species has been recorded. However, management of human activities that impact cetacean populations in the area is inadequate, in part due to poor knowledge on cetacean occurrence and the lack of systematic surveys. We reviewed existing knowledge on cetacean distribution between Morocco and Liberia an...
Completing the picture: using vertebrae as well as otoliths in diet analysis reveals new preferred prey of great skuasNARA Subscribed
Knowledge of the diet of marine predators such as seabirds is fundamental to understanding the ecological cascades they may influence and the impact that environmental changes may have on them. Diet analysis of seabirds frequently relies on the identification of fish otoliths in pellets. However, it is recognised that the true dietary importance of fish with small and fragile otoliths is likely underestimated, requiring an add...
Using fusion effects to decrease uncertainty in distance sampling models when collating data from different surveysNARA Subscribed
Estimates of population abundance are required to study the impacts of human activities on populations and assess their conservation status. Despite considerable effort to improve data collection, uncertainty around estimates of cetacean densities can remain large. A fundamental concept underlying distance sampling is the detection function. Here we focus on reducing the uncertainty in the estimation of detection function para...
Age and growth analysis of Loliginidae squid paralarvae in the NW Spanish coast using statolith increment countsNARA Subscribed
Knowledge of recruitment to a fishery is particularly important in short-lived species, like most cephalopods, in which there is a complete turnover of individual every 1 or 2 years. In this study, age, body length, statolith length and growth rates of loliginid paralarvae ( Alloteuthis media , A. subulata and Loligo vulgaris ) were determined to evaluate the form of the growth curve and differences between species and hatchin...
Identifying sustainability priorities among value chain actors in artisanal common octopus fisheriesNARA Subscribed
The United Nations (UN) Decade of Ocean Science highlights a need to improve the way in which scientific results effectively inform action and policies regarding the ocean. Our research contributes to achieving this goal by identifying practical actions, barriers, stakeholder contributions and resources required to increase the sustainability of activities carried out in the context of artisanal fisheries to meet UN Sustainabl...
Inshore waters off the south coast of Ireland are an important foraging area for a range of cetacean species. Some of the main prey species of these cetaceans are herring and sprat, two economically valuable fish species in the region. The Celtic Sea herring stock suffered a marked decline in 2013. The present study aimed to investigate potential changes in the ecosystem associated to the herring decline and to determine the p...
Cephalopods, a gap in the European Marine Strategy Framework Directive and their future integrationNARA Subscribed
With the aim of maintaining or obtaining good environmental status in the Northeast Atlantic and northern Mediterranean Sea, the European Marine Strategy Framework Directive (EU-MSFD) came into force in 2008. All EU Member States (MS) have the task of assessing the current state of their adjacent waters to guarantee sustainable use of marine resources and healthy ecosystems for the current and future generations. Although the...
Identifiable food remains were analyzed from 46 stomachs of striped dolphins ( Stenella coeruleoalba ) stranded in southern Spain between 2007 and 2014. Results suggest that the species feeds mainly on mesopelagic and neritic fish, but also on oceanic squids. Fish species of the family Myctophidae were the main prey in terms of numerical importance and reconstructed prey weight (62% N and 29% W), followed by squids of the fami...
Monitoring marine mammal populations is essential to permit assessment of population status as required by both national and international legislation. Traditional monitoring methods often rely on visual and/or acoustic detections from vessels and aircraft, but limitations including cost, errors in the detection of some species and dependence on taxonomic expertise, as well as good weather and visibility conditions often limit...
The world’s largest extant fish, the whale shark Rhincodon typus , is one of the most-studied species of sharks globally. The discovery of predictable aggregation sites where these animals gather seasonally or are sighted year-round – most of which are coastal and juvenile-dominated – has allowed for a rapid expansion of research on this species. The most common method for studying whale sharks at these sites is photographic i...
Shorewatch is a citizen science project, managed by Whale and Dolphin Conservation (WDC), that records the occurrence of cetaceans during regular, standardized watches from a series of locations along the coast of Scotland (United Kingdom). Observer training and a clearly defined protocol help deliver a valuable source of information about cetacean occurrence and activity along the coast. Between 2005–2018, over 52000 watches...
Predicting Cetacean Distributions in the Eastern North Atlantic to Support Marine ManagementOA Marine
Data on species occurrence at the scale of their distributional range and the determination of their habitat use requirements are essential to support conservation and define management plans that account for their habitat requirements. For wide-ranging species, such as cetaceans, especially considering that their marine habitats include offshore areas, collection of such data is challenging. In the absence of dedicated survey...
Spiral valve parasites of blue and common thresher sharks as indicators of shark feeding behaviour and ecologyNARA Subscribed
This study documented the parasite faunas of the spiral valves of blue sharks Prionace glauca (L. 1758) and common thresher sharks Alopias vulpinus (Bonnaterre, 1788) caught in the California Current Large Marine Ecosystem (CCLME) north of the Mexican border. The spiral valves of 18 blue and 19 thresher sharks caught in the CCLME from 2009 to 2013 were examined for parasites. Seven parasite taxa were found in blue sharks and n...