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Wales, United Kingdom

Dolman S.J.,Whale and Dolphin Conservation Society WDCS | Dolman S.J.,University of Aberdeen | Evans P.G.H.,Sea Watch Foundation | Evans P.G.H.,Bangor University | And 3 more authors.
Marine Pollution Bulletin

Various reviews, resolutions and guidance from international and regional fora have been produced in recent years that acknowledge the significance of marine noise and its potential impacts on cetaceans. Within Europe, ACCOBAMS and ASCOBANS have shown increasing attention to the issue. The literature highlights concerns surrounding the negative impacts of active sonar on beaked whales in particular, where concerns primarily relate to the use of mid-frequency active sonar (1-10. kHz), as used particularly in military exercises. The authors review the efforts that European regional policies have undertaken to acknowledge and manage possible negative impacts of active sonar and how these might assist the transition from scientific research to policy implementation, including effective management and mitigation measures at a national level. © 2010 Elsevier Ltd. Source

Banguera-Hinestroza E.,Durham University | Banguera-Hinestroza E.,King Abdullah University of Science and Technology | Evans P.G.H.,Sea Watch Foundation | Mirimin L.,Sea Watch Foundation | And 6 more authors.
Conservation Genetics

Highly mobile species in the marine environment may be expected to show little differentiation at the population level, but this is often not the case. Instead cryptic population structure is common, and effective conservation will require an understanding of how these patterns evolve. Here we present an assessment from both sides of the North Atlantic of differentiation among populations of a dolphin species that inhabits mainly pelagic waters, the Atlantic white-sided dolphin. We compare eleven putative populations in the western and eastern North Atlantic at mtDNA and microsatellite DNA loci and find reduced nucleotide diversity and signals for historical bottlenecks and post-bottleneck expansions in all regions. We calculate expansion times to have occurred during the early Holocene, following the last glacial maximum (LGM). We find evidence for connectivity among populations from either side of the North Atlantic, and differentiation between putative populations in the far northeast compared with all other areas sampled. Some data suggest the possibility of separate refugia during the LGM explaining this pattern, although ongoing ecological processes may also be a factor. We discuss the implications for developing effective programs of conservation and management in the context of ongoing anthropogenic impact. © 2014 Springer Science+Business Media Dordrecht. Source

Gero S.,Dalhousie University | Milligan M.,Dalhousie University | Rinaldi C.,Association Evasion Tropicale | Francis P.,Anchorage Whale Watch | And 7 more authors.
Marine Mammal Science

There is substantial geographic variation in the behavior and social structure of sperm whales worldwide. The population in the Eastern Caribbean is thought to be isolated from other areas in the North Atlantic. We describe the behavior and social structure of the sperm whales identified off Dominica during an eight year study (2005-2012; 92% of photographic identifications) with supplementary data collected from seven other organizations dating as far back as 1981. A total of 419 individuals were identified. Resighting rates (42% of individuals between years) and encounter rates with sperm whale groups (mean = 80.4% of days at sea) among this population were both comparatively high. Group sizes were small (7-9 individuals) and were comprised of just one social unit (mean = 6.76 individuals, SD = 2.80). We described 17 units which have been reidentified off Dominica across 2-27 yr. Mature males are seen regularly off Dominica, but residency in the area lasts only a few days to a few weeks. Males were reidentified across years spanning up to a decade. Management of this population within the multinational Wider Caribbean Region will require governments to work towards international agreements governing sperm whales as a cross-border species of concern. © 2013 Society for Marine Mammalogy. Source

Dolman S.,Whale and Dolphin Conservation WDC | Baulch S.,Environmental Investigation Agency EIA | Evans P.G.H.,Sea Watch Foundation | Read F.,Whale and Dolphin Conservation WDC | Ritter F.,Whale and Dolphin Conservation WDC
Marine Policy

For decades, cetacean bycatch has been a major conservation and welfare concern in Europe, with high numbers of harbour porpoises, dolphins and whales continuing to die each year. Despite binding legal requirements to reduce bycatch, there has been limited effective monitoring or mitigation. Bycatch is also an important welfare issue. At this critical juncture, with discussion of incorporating monitoring and mitigation of bycatch of protected species in Europe into the Data Collection Framework and Technical Measures Framework taking place to help deliver the reformed Common Fisheries Policy (CFP), a clear, effective strategy could identify the steps that are required by all EU Member States to reduce bycatch towards zero. Here, implementation of current monitoring and mitigation obligations are reviewed. Recommendations are made for the provision of clear EU guidance in order to improve and unify population surveillance and bycatch monitoring, with enhanced implementation and enforcement from Member States. A more regionalised evidence-based approach to monitoring and mitigation is in line with the move to more regionalised management under the CFP, with Member States robustly showing that bycatch levels are decreasing over a set period of time (e.g. 5 years) by a specified amount. To this end, an EU Action Plan on Cetacean Bycatch, comparable to the existing 2012 Action Plan for reducing incidental catches of seabirds in fishing gear, might be beneficial and could ultimately form a model for an international Food and Agricultural Organisation (FAO) Cetacean Bycatch Reduction Action Plan. © 2016 Elsevier Ltd. Source

Anderwald P.,University College Cork | Anderwald P.,Durham University | Evans P.G.H.,Sea Watch Foundation | Dyer R.,Arisaig Marine Ltd. | And 3 more authors.
Marine Ecology Progress Series

Because pelagic prey concentrations are patchy in both space and time, predators such as marine mammals require high degrees of flexibility in their habitat use. We tested the hypothesis that minke whales Balaenoptera acutorostrata adjust their habitat use during the feeding season at different spatial scales: their overall distribution should be determined by broad-scale oceanographic features, while foraging activity at finer scales should be dictated by short-term changes in habitat conditions. Results from generalized additive models indicate that minke whale distribution off the west coast of Scotland is dependent largely on temporally variable parameters (sea surface temperature in spring, chlorophyll concentration in autumn), in addition to depth and topography. However, fine-scale foraging behaviour was dictated by the strength and direction of tidal currents. Seasonal distribution patterns according to environmental parameters were largely consistent between 2 different spatial scales, and over a time period of 15 yr. Significantly higher sighting rates occurred in areas of predicted sandeel Ammodytes marinus presence in spring, but not during the rest of the summer, while in August and September, prey samples from the core study area consisted almost entirely of sprat Sprattus sprattus. The low energetic cost of swimming in minke whales and their ability to switch between different prey according to their seasonal availability thus appears to allow them to readily respond to temporal changes in pelagic prey concentrations at different scales. This occurs through a distribution influenced by temporally variable parameters (temperature and chlorophyll concentration), combined with adjustments in foraging activity dependent on variable conditions at fine spatial scales (tides). © Inter-Research 2012. Source

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