Callum M Roberts results 34
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Crises narratives surrounding the societal challenges of biodiversity loss, climate change, and human health and well-being dominate current debates in global environmental politics. These challenges are deeply interconnected and require transformative and integrated change. Marine and coastal Nature-based Solutions (blue NbS) are an opportunity to minimise harmful human impacts on these ecosystems while providing co-benefits...
Chasing Fish: 130 Years of Innovation, Displacement and Depletion in Scottish FisheriesNARA Subscribed
Rebuilding the depleted fisheries of the 21st century requires an understanding of past drivers of their decline. Despite Scotland's central role in the commercial exploitation of North Sea fisheries for over a century, associations between technological innovations, regulatory introductions and fishery landings have not previously been quantified. Here we use data from annual Scottish Government fisheries reports (1890–2020)...
The UK’s expanding global reach for seafood over 120-yearsNARA Subscribed
Seafood markets have become increasingly internationalised over the course of the twentieth century, induced by expanding footprints of fishing fleets, improved communication and transport infrastructure, and trade agreements. We compiled archival UK seafood import data from UK Government, SEAFISH and FAO sources to track the expansion of the UK’s global reach for seafood products from 1900 to 2020. UK domestic fisheries landi...
Fishing with active bottom‐contacting gears (here collectively described as 'bottom trawling') is considered the greatest source of anthropogenic disturbance to marine sediments. However, uncertainties are apparent in studies evaluating the severity of their impacts from fishing with these gears at the global scale. A major uncertainty is the estimation of the area of seabed disturbed by applying European‐based vessel size to...
Individual flexibility in group foraging behaviour of reef manta rays (Mobula alfredi)NARA Subscribed
Flexibility in animal foraging strategies can increase overall feeding efficiency for individuals. For example, group foraging can increase the efficiency of resource exploitation; conversely solo foraging can reduce intraspecific competition, particularly at low resource densities. The cost–benefit trade-off of such flexibility is likely to differ within and among individuals. Reef manta rays ( Mobula alfredi ) are large filt...
Pulmonary vascular tone is modulated by nucleotides, but which P2 receptors mediate these actions is largely unclear. The aim of this study, therefore, was to use subtype-selective antagonists to determine the roles of individual P2Y receptor subtypes in nucleotide-evoked pulmonary vasodilation and vasoconstriction. Isometric tension was recorded from rat intrapulmonary artery rings (i.d. 200–500 µm) mounted on a wire myograph...
Subtidal marine sediments are one of the planet's primary carbon stores and strongly influence the oceanic sink for atmospheric CO 2 . By far the most widespread human activity occurring on the seabed is bottom trawling/dredging for fish and shellfish. A global first‐order estimate suggested mobile demersal fishing activities may cause 0.16–0.4 Gt of organic carbon (OC) to be remineralized annually from seabed sediment carbon...
Courtship and mating behaviour of manta rays Mobula alfredi and M. birostris in the MaldivesNARA Subscribed
The aim of this 14 year study was to elucidate the entire courtship and mating behaviour of manta rays Mobula alfredi and M. birostris using behavioural observations, video and photographic records. From 2003 to 2016, over 11,000 surveys were undertaken at known manta ray aggregation sites in the Maldives to record any observed manta rays reproductive activity. From 47,591 photo‐ID sightings, 4,247 individual M. alfredi were i...
Marine recreational fishing ( MRF ) is a high‐participation activity with large economic value and social benefits globally, and it impacts on some fish stocks. Although reporting MRF catches is a European Union legislative requirement, estimates are only available for some countries. Here, data on numbers of fishers, participation rates, days fished, expenditures, and catches of two widely targeted species were synthesized to...
Aim Despite predictions of high extinction risk resulting from climate change, range expansions have been documented more frequently than range retractions, prompting suggestions that species can endure climatic changes by persisting in cool or damp microclimates. We test whether such ‘microrefugia’ exist. Location The U nited K ingdom. Methods We examine fine‐scale changes in the plant communities of a coastal grassland over...
The International Union for Conservation of Nature Red List of Endangered Species employs a robust, standardized approach to assess extinction threat focussed on taxa approaching an end‐point in population decline. Used alone, we argue this enforces a reactive approach to conservation. Species not assessed as threatened but which occur predominantly in areas with high levels of anthropogenic impact may require proactive conser...
Many over‐exploited marine ecosystems worldwide have lost their natural populations of large predatory finfish and have become dominated by crustaceans and other invertebrates. Controversially, some of these simplified ecosystems have gone on to support highly successful invertebrate fisheries capable of generating more economic value than the fisheries they replaced. Such systems have been compared with those created by moder...