To aid management and conservation of widely distributed marine vertebrate species, it is necessary to have a knowledge and understanding of their spatial ecology. We tracked 10 adult female ...loggerhead turtles Caretta caretta from Masirah Island, Sultanate of Oman, which hosts one of the world's largest breeding aggregations. Transmitters were specifically deployed early in the nesting season to enable tracking throughout the internesting and post-nesting habitats. Turtles displayed a dichotomy in behaviour during the internesting period, with 6 remaining close to Masirah Island and the others undertaking circuitous oceanic loops, hundreds of kilometres in length. This behaviour did not appear to be related to body size. Tracking-derived minimum clutch frequency was on average (+/- SD) 4.8 +/- 1.2 nests (n = 8 ind.). Post-nesting migrations revealed a propensity towards long-term utilisation of oceanic habitats in the region between Socotra Island (Yemen) and the mainland of Yemen/Oman, with 76 +/- 15.4% of time spent in oceanic habitat (n = 8 ind.). The spatial footprint of our tracked turtles was found to be far less than that of a similar number of turtles that were tagged later in the same season (from a separate unpublished study) and from long-distance returns of flipper tags. The spatial and temporal sub-structuring of the population highlights the need for more comprehensive tracking projects, with deployments across the breeding season in multiple years, in order to obtain reliable estimations of high-use foraging habitats of widely dispersed marine vertebrates. Variation in behaviour patterns suggests the need for diverse conservation measures.
We followed the movements of 9 adult female olive ridley turtles Lepidochelys olivacea after nesting on Masirah Island, Oman, using satellite tracking. Their post-breeding migrations ranged from 85 ...to 796 km. Three individuals travelled north to foraging grounds in Pakistan, Iran and the United Arab Emirates. The other 6 turtles remained in Omani seas for extended periods (mean +/- SD = 171.3 +/- 109.4 d; range = 40 to 310 d). These locally resident turtles experienced biannual cooling of sea temperatures due to the effect of the west Arabian Sea upwelling which was not experienced by those that migrated to the north. Indications of disparity in turtle size between foraging locations are identified for the first time in this species. The majority of turtles (8) settled in coastal areas of water depth 100 min) in water warmer than 21 degree C, which is a feature unique to olive ridleys amongst sea turtles. They displayed a shift to shorter diving after breeding, indicating increased activity levels. The entire spatial footprint of olive ridley dispersal remained within a putative regional management unit (RMU) for this species in the western Indian Ocean, supporting its delineation. We reveal Oman's key role in conserving this demographic unit, with 6 turtles remaining within its national boundary. Our data add to the growing body of evidence that marine turtles show varied migration behaviours within populations, thus complicating their management.
The Arabian Peninsula and surrounding countries host a large number of nesting and foraging turtles. Most countries in the region host populations of two or three sea turtle species. Perhaps the best ...known nesting area in the region is Masirah Island, in the Sultanate of Oman, where hawksbills, olive ridleys and green turtles, in addition to the >30,000 loggerhead turtles, come to nest each summer. In conjunction with the Ministry of Environment of Oman, TOTAL Foundation and TOTAL S.A. - Muscat Branch have been working for four years on a sea turtle conservation project on Masirah Island. The Foundation recently sponsored a second sea turtle conservation project in Kuwait, with the aim of studying and protecting green and hawksbill turtle populations on the atolls of Qaru, Kubbar and Umm Al-Maradim. In cooperation with public and private authorities in the French Antilles, TOTAL Foundation co-sponsors another conservation project in Guadeloupe, coordinated by the NGO Kap-Natirel.
To fully assess the sustainability of energy from home-grown biomass, the whole production combustion life cycle of the crops needs to be considered across a broad range of ecosystem service ...indicators. A sustainability framework needs to consider impacts within the UK and beyond arising across the life cycle. This paper presents a framework for making such an assessment using data collected by two different literature summary techniques but processed using the same qualitative scoring system, recording matrices and graphical presentation of results. It illustrates what is known about the impacts on ecosystem services of UK produced biomass crops (short rotation coppice and Miscanthus), suggesting a lack of research relating to upstream, operational and downstream elements of the energy life cycle, and a focus on the growth-cycle of the crops. The specific results obtained are sensitive to choices made in the literature review process, but the approach is useful in its ability to summarise a large amount of data and applicability to other energy feed-stocks, enabling a comparison of ecosystem impacts between energy systems.
•Presents a framework to assess ecosystem service impacts across life cycle stages.•The technique is applied to UK and global impacts of UK-produced biomass crops.•Results suggest a research focus on the growth-cycle of crops.•Less research has been conducted on upstream, operational and downstream impacts.•The approach enables a comparison of ecosystem impacts between energy systems.
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