the humboldt current system of northern and central chile - figema

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MARTIN THIEL ET AL.reported (Neill et al. 2006). Recently, patches of C. fragile have been observed within the MPA(R. Villablanca personal observations), highlighting the importance of considering connectivitywith surrounding areas and the constraints of aquaculture sites for selecting location of MPAs(Micheli et al. 2004).The establishment of MPAs in Chile has so far been based on anecdotal recommendations (e.g.,resource management, tourist attractions) rather than scientific criteria. This approach is consideredinadequate to effectively protect biodiversity (Meir et al. 2004, Sutherland et al. 2004). Currentstrategies for implementing MPA networks require a systematic planning conservation method toidentify optimal sites for protection of biodiversity (Sayre et al. 2000, Beck & Odaya 2001). Thefirst step in planning an MPA is the assessment and mapping (Geographic Information System —GIS) of the coastal marine biodiversity, the physical environment and major threats (e.g., humanuses) and then the identification of priority sites using Decision Support Systems (DSS) based onalgorithms (Sala et al. 2002, Leslie et al. 2003). A DSS based on species richness has been usedto identify priority areas for marine vertebrate conservation along the Chilean coast (Tognelli et al.2005). Habitat classification is generally considered as the conservation goal in the DSS (Robertset al. 2003). However, benthic surveys along the Chilean coast (C. Gaymer & C. Dumont unpublisheddata) revealed that communities are probably more appropriate to characterise the benthicenvironment and consider the ecosystem processes (e.g., trophic cascades; Shears & Babcock 2003),ecological interactions (e.g., predator-prey; Micheli et al. 2004) and population connectivity (e.g.,larval dispersal; Palumbi 2003). Moreover, there is an urgent need for more scientific informationin Chilean marine biodiversity (e.g., there is a lack of taxonomic expertise), population connectivity(e.g., identifying source and sink populations) and ecological processes (in particular speciesinteractions in subtidal habitats are poorly studied).Although ecological knowledge is a key component in developing MPAs, the managementeffectiveness is the most important challenge for the success of an MPA (Mascia 2004, Pomeroyet al. 2004). A major difficulty arises from the way in which marine reserves and MUMPAs havebeen established in Chile. The former were created by an imposition from the central authority(fisheries ministry) without consulting the stakeholders, who are mostly in disagreement with thisnew status. This establishment strategy has turned enforcement into a complicated task for thefisheries authority, and this may turn into a major threat for the success of present and future MPAs.For example, since its creation in 1997, the marine reserve La Rinconada has been affected byfrequent illegal extractions of scallops (M. Avendaño personal observations). Social conflicts due tolack of communication between the authority and the stakeholders are also present within the recentlycreated marine reserves Isla Choros-Damas and Isla Chañaral. In contrast, a participative processtook place in the establishment of the MUMPA Isla Grande de Atacama, incorporating most of therelevant actors (i.e., administrative authorities, stakeholders, managers, scientists and fishermen),offering the opportunity to evaluate contrasting interests in order to reduce potential conflicts. Socialcosts should be evaluated before the establishment of MPAs and a formal educational process shouldbe implemented by the authorities to teach the importance of MPAs in developing sustainableexploitation of resources (Mascia 2004). The government should also negotiate compensations andpropose alternative activities (e.g., tourism) to fishermen, who are the ancestral users of the MPAareas, and avoid creating high expectations (Mascia 2004, Sobel & Dahlgren 2004).Ideally, an international MPA network (from Ecuador to Chile) including the connectivity amongMPAs should be implemented to effectively preserve biodiversity in the HCS. This should be achievedusing the support of international tools and agreements, and international non-governmental organisations(NGOs) in order to co-ordinate and improve the quality of scientific information and reducethe costs (Balmford et al. 2004). Moreover, the Chilean government must contribute to funding forimplementation and functioning of MPAs as successful conservation experiences from all over the298
THE HUMBOLDT CURRENT SYSTEM OF NORTHERN AND CENTRAL CHILEworld have demonstrated that self-funding (e.g., through tourism business) is not feasible (Balmfordet al. 2004).Outlook, long-term research vision and future research frontiersAn outlook of the pressing scientific questions and tasks to be addressed in the short/mid-termfuture (during the next decade) within the HCS of northern and central Chile should, as a minimum,include (1) studies of ocean–atmosphere interactions and offshore oceanography, (2) research ininshore and offshore oxygen-minimum ecosystems, (3) research on inner inshore coastal oceanographyand benthic-pelagic linkages, (4) development of an ecosystem-based adaptive resourcemanagement approach to fisheries that integrates socioeconomic aspects, (5) implementation of acoastal overarching network system for marine conservation-management, (6) novel approaches incoastal mariculture, (7) studies of marine non-indigenous species (NIS), (8) marine molecularbiology, particularly on genomics, and (9) training of Chilean marine taxonomists.A long-term HCS vision (during the coming two decades) should also, as a minimum, include(1) intensification of precautionary and integrative ecosystem management; (2) implementation ofa high-sea conservation policy; (3) intensification of research on the continental slope, deep-seaand abyssal ecosystems; (4) scientific and technological research on deep-sea gas (methane)hydrates; and (5) evaluations of the effects of future climate change.Short/mid-term scientific outlookResearch on ocean–atmosphere interactions and offshore oceanographyThe HCS offers unique opportunities for offshore oceanographic studies (e.g., Strub et al. 1998)and considered as a whole, Chile and Peru represent between 15% and 20% of the world’s fisherylandings. Large-scale fluctuations in ocean climate (ENSO and the PDO) dominate interannual andinterdecadal variability in the ocean, which in turn are linked to upwelling and climate changes(Chavez et al. 2003) and are considered key elements in the HCS functioning. Upwelling systemspresently are experiencing ‘anomalous changes’ such as profound changes in the physical andbiogeochemical properties in the California Current Systems (Freeland et al. 2003, Grantham et al.2004), massive nitrogen loss in the Benguela upwelling system (Kuypers et al. 2005), and hydrogensulphide eruptions in the Atlantic Ocean off southern Africa and linked abrupt degradation ofupwelling systems (Bakun & Weeks 2004, Weeks et al. 2004, Arntz et al. 2006). Such interannualand decadal variability and anomalous changes may intensify due to global climate changes, whichwill also affect the HCS, causing important changes in productivity, biogeochemical cycling andfisheries. Research on these and related oceanographic topics is urgently needed for the HCS.Research on inshore and offshore oxygen-minimum ecosystemsOxygen-minimum zones (OMZs) in the ocean generally form along the EBCs. The decompositionof upwelling-derived biomass in combination with sluggish circulation of mid-water massesstrongly enhance the hypoxia conditions, as is the case in the HCS (Levin & Gage 1998, Moraleset al. 1999, Levin 2002, Helly & Levin 2004, Ulloa & De Pol 2004). The HCS is characterised bythe relative shallowness of the oxygen-minimum layer. The OMZ produces peculiar environmentswith organisms highly resistant to low oxygen concentrations (Levin et al. 2001, Gallardo et al.2004). These environments are unique in the HCS and quite different from those off California(Arntz et al. 2006). They offer diverse opportunities to develop frontier research, ranging from299
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