Brereton T.,Marinelife |
Jones D.,Marine Discovery |
Leeves K.,AK Wildlife Cruises |
Lewis K.,Marinelife |
And 2 more authors.
Journal of the Marine Biological Association of the United Kingdom | Year: 2017
In this study photo-identification data were used to better understand movements, population structure and abundance of common bottlenose dolphin (Tursiops truncatus) in south-west England and surrounding waters, to inform conservation efforts. A catalogue of 485 photographic sightings of 113 individuals was compiled from ~150 common bottlenose dolphin encounters made on 87 dates between March 2007 and January 2014. From these and other data, three likely sub-populations were identified in the western English Channel, demarcated by bathymetry and distance to land: (1) south-west England – inshore Cornwall to Devon, (2) offshore English/French waters and (3) inshore France from Brittany to Normandy. Maximum abundance estimates for south-west England coastal waters, using two methods, ranged between 102 and 113 (range 87–142, 95% CL) over the period 2008–2013, likely qualifying the region as nationally important, whilst the yearly maximum was 58 in 2013. The population was centred on Cornwall, where 19 well-marked animals were considered ‘probable’ residents. There were no ‘probable’ resident well-marked individuals found to be restricted to either Devon or Dorset, with animals moving freely within coastal areas across the three counties. Movements were also detected within offshore English waters and French waters (from other studies) of the western English Channel, but no interchange has as yet been detected between the three regions, highlighting the possible separation of the populations, though sample sizes are insufficient to confirm this. Given the findings, south-west England waters should be considered as a separate management unit requiring targeted conservation efforts. Copyright © Marine Biological Association of the United Kingdom 2017
Jones A.R.,UK National Oceanography Center |
Jones A.R.,University of Adelaide |
Wynn R.B.,UK National Oceanography Center |
Yesou P.,Office National de la Chasse et de la Faune Sauvage ONCFS |
And 6 more authors.
Endangered Species Research | Year: 2014
We investigated spatio-temporal distribution patterns of the Critically Endangered Balearic shearwater Puffinus mauretanicus in the northern part of its migratory range, using a combination of effort-corrected land- and boat-based survey data (2007-2010). The species was recorded regularly along the western English Channel (Western Channel) coasts of northwest France and the southwest UK, with peak counts occurring during the summer and autumn months. Foraging aggregations comprising hundreds to thousands of birds (~1 to 20% of the global population) were recorded in the large shallow embayments of northern Brittany in all survey years. Elsewhere, most birds were recorded on passage, with maximum birds-per-hour (BPH) of 169 offnorthwest France and 36 offthe southwest UK. Few birds were recorded offshore, beyond sight of land. A distance-from-shore analysis revealed that the species passed closer to shore than other pelagic seabirds such as sooty shearwater Puffinus griseus. A constant-effort seasonal survey from the southwest tip of the UK mainland recorded the species on 93% of survey days, with BPH rates peaking in the morning between 08:00 and 11:00 h. These results have important monitoring and conservation implications for this Critically Endangered species. In particular, the records of large aggregations in spatially restricted areas of the Western Channel during the inter-breeding period suggests the species could be vulnerable to impacts such as oil spills, or disturbance from offshore construction projects. We also provide evidence that some birds remain in the survey area during the breeding season, suggesting it may be an important site for non-breeding birds. © The authors 2014.
McClellan C.M.,University of Exeter |
Brereton T.,Marinelife |
Dell'Amico F.,Center Detudes Et Of Soins Pour Les Tortues Marines |
Johns D.G.,Sir Alister Hardy Foundation for Ocean Science |
And 9 more authors.
PLoS ONE | Year: 2014
The temperate waters of the North-Eastern Atlantic have a long history of maritime resource richness and, as a result, the European Union is endeavouring to maintain regional productivity and biodiversity. At the intersection of these aims lies potential conflict, signalling the need for integrated, cross-border management approaches. This paper focuses on the marine megafauna of the region. This guild of consumers was formerly abundant, but is now depleted and protected under various national and international legislative structures. We present a meta-analysis of available megafauna datasets using presence-only distribution models to characterise suitable habitat and identify spatially-important regions within the English Channel and southern bight of the North Sea. The integration of studies from dedicated and opportunistic observer programmes in the United Kingdom and France provide a valuable perspective on the spatial and seasonal distribution of various taxonomic groups, including large pelagic fishes and sharks, marine mammals, seabirds and marine turtles. The Western English Channel emerged as a hotspot of biodiversity for megafauna, while species richness was low in the Eastern English Channel. Spatial conservation planning is complicated by the highly mobile nature of marine megafauna, however they are important components of the marine environment and understanding their distribution is a first crucial step toward their inclusion into marine ecosystem management. © 2014 McClellan, et al.
Lambert E.,University of Aberdeen |
MacLeod C.D.,University of Aberdeen |
Hall K.,University of Aberdeen |
Brereton T.,Marinelife |
And 6 more authors.
Endangered Species Research | Year: 2011
As with many other taxa, climate change is expected to result in geographic range shifts of cetacean species as they track changes in temperature to remain within their ecological niches. Such changes in geographic range could have implications for the conservation and management of cetaceans. Here, we propose a bioclimatic envelope modelling approach for providing quantitative predictions of how the ranges of cetacean species may respond to changing water temperatures. This combines predictions from habitat niche and 'thermal' niche models for an individual species to determine probable geographic range under specific climatic conditions. However, if this approach is to be used to inform conservation strategies, it is essential that the ability to predict responses to environmental change is validated beyond the period of data collection used to construct the models. Therefore, in addition to validation of modelled current range, we included a step to validate the models' ability to predict previous changes in range over time in response to climatic changes using independent data. We demonstrate this approach using common dolphin Delphinus delphis data from the Northeast Atlantic. The combined model was constructed with data collected between 1980 and 2007, and validated using independent distributional records collected between 1930 and 2006. The validated model was then applied to predict future range between 2010 and 2069, based on projected water temperatures. Thus, the modelling approach is shown to provide the type of information required to help ensure that conservation and management strategies remain effective in the face of a changing climate. © Inter-Research 2011.
Watson H.,Bangor University |
Watson H.,University of Glasgow |
Hiddink J.G.,Bangor University |
Hobbs M.J.,BSG Ecology |
And 2 more authors.
Marine Ecology Progress Series | Year: 2013
Understanding spatial and temporal variability in the distribution of seabirds is fundamental for the conservation and management of marine ecosystems. In the absence of large-scale systematic survey data, the application of standard habitat modelling techniques to predict the atsea distributions of seabirds at large spatial scales has been limited. In this study, we examine the utility of relative environmental suitability (RES) modelling to predict large-scale distributions and habitat suitability for 6 seabirds in the North Atlantic. An index of habitat suitability was derived by relating niche characteristics to environmental attributes. Predictive performance of models was evaluated with Receiver Operating Characteristic plots, using independent survey data from the Bay of Biscay. RES models performed significantly better than null models at predicting relative likelihood of occurrence for 5 out of 6 species. Qualitative assessment showed that model outputs corresponded well with published range maps, though a common discrepancy was the inclusion of enclosed seas in which species are not known to regularly occur. This study de monstrates that RES modelling can be used to predict large-scale habitat suitability for wide- ranging marine animals for which occurrence data are limited and biased in geographical extent. RES predictions represent simple, testable hypotheses concerning a species' potential niche in respect of a few environmental predictors. RES modelling can help to identify biodiversity hotspots, predict effects of climate change and develop criteria for designating marine protected areas © 2013 Inter-Research.