I thank Heather Koldeway and Matthew Gollock from Zoological Society of London, John Turner from Bangor University, Nick Dulvy from Simon Frazer University, and Chas Anderson, for very helpful comments on the manuscript. “
“The main threat to biodiversity loss in the marine environment is exploitation which results in species population Ipilimumab supplier declines and extinctions, habitat degradation, and ecosystem changes (Essington et al., 2006, Heithaus et al., 2008, Hutchings and Baum, 2005, Jackson et al., 2001, Myers and Worm, 2003 and Thurstan et al., 2010). International policy commitments now aim

to reduce this loss, supported by the development of threat indicators that can monitor environmental concerns related to fisheries (Dulvy et al., 2006). Overexploitation of apex predators has dramatically influenced biological communities by triggering cascading effects down food webs, leading to decreases in diversity and/or productivity, loss Raf inhibitor of ecosystem services and, in some instances, ecosystem collapse (Agardy, 2000, Jackson et al., 2001, Worm et al., 2002, Ferretti et al., 2010, Pinnegar et al., 2000 and Myers et al.,

2007). The majority of these studies relate to coastal ecosystems and currently there is insufficient evidence available to make an empirical assessment as to whether similar events are occurring within the pelagic realm (Worm et al., 2003). However, widespread shifts in the species targeted by some pelagic fisheries towards lower trophic-level species Decitabine suggest that changes in ecosystem structure have occurred (Verity et al., 2002). An ecosystem-based approach to fisheries management is now thought necessary to understand the overall impacts of fishing (Botsford et al., 1997 and Chuenpagdee et al., 2003). The Chagos Archipelago – also known as the British Indian Ocean Territory, BIOT, and subsequently referred to as Chagos/BIOT – is one of the UK’s fourteen overseas territories. The archipelago comprises of about 55 islands

located in the centre of the Indian Ocean, has the greatest marine biodiversity in the UK and its territories (Sheppard, 2000a), and is of considerable importance to global biodiversity (Procter and Fleming, 1999). UK government committees have previously highlighted their concerns about the lack of attention to, and co-ordination of, environmental initiatives in the UK overseas territories, with 39 recorded terrestrial extinctions and the continued threat of extinction of around 240 other species (House of Commons Environmental Audit Committee, 2008 and House of Commons Foreign Affairs Committee, 2008). The remoteness of Chagos/BIOT combined with very low levels of anthropogenic disturbance – the only human presence is a US military base on Diego Garcia – has resulted in some of the cleanest seas and healthiest reef systems in the world (Everaarts et al., 1999).