Introduction

Pelagic ecosystems and their fisheries are of particular economic and social importance to the countries and territories of the Wider Caribbean for various reasons. In some countries (e.g. Barbados, Grenada) commercial pelagic fisheries already contribute significantly to total landings and seafood export foreign exchange earnings. Ports and postharvest facilities service the vessels, ranging from artisanal canoes to industrial longliners, and their catch which often reaches tourists as well as locals (Mahon and McConney 2004). In other places where the focus has previously been on inshore and demersal fisheries (e.g. Antigua and Barbuda, Belize) there is growing interest in the potential of pelagic fisheries development. This potential lies not only in commercial fisheries, but also in the high-revenue and conservation-aware recreational fisheries well established in a few locations (e.g. Puerto Rico, Costa Rica) and undertaken at a lower level in many others.

Underlying all of this is the complexity due to many of the valued pelagics being migratory or highly migratory shared and straddling stocks falling under the 1995 United Nations Fish Stocks Agreement and subject to several international instruments and management regimes, such as those of the International Commission for the Conservation of Atlantic Tunas (ICCAT). The web of linkages across Caribbean marine jurisdictions and organizations is complex (McConney et al. 2007). The related issues call for an ecosystem approach (McConney and Salas Chapter 7; Schuhmann et al. Chapter 8) and some progress has already been made at multiple levels (Fanning and Oxenford Chapter 16; Singh-Renton et al. Chapter 14).

This synthesis chapter presents the outputs of facilitated symposium sessions specifically related to achieving and implementing a shared vision for the pelagic ecosystem in marine ecosystem based management (EBM) in the Wider Caribbean. The methodology was described in Chapter 1 of this volume. This chapter first describes a vision for the pelagic ecosystem and reports on the priorities assigned to the identified vision elements. It then addresses how the vision might be achieved by taking into account assisting factors (those that facilitate achievement) and resisting factors (those that inhibit achievement). The chapter concludes with guidance on the strategic direction needed to implement the vision, identifying specific actions to be undertaken for each of the vision elements.

ABSTRACT

The surface and aeolian dust on Mars is rich in iron compounds, and significant quantities of dust have been observed to stick to permanent magnets that are either exposed to the dusty atmosphere, exposed to dust released by grinding into rocks, or inserted into the soil. All successful lander missions to Mars so far have carried permanent magnets of various designs for the purpose of studying dust magnetic properties. The magnetism of the aeolian dust is the result of the presence of magnetite, which apparently derives from mechanical weathering of magnetite-rich surface rocks. A strong correlation between the elements titanium and iron is observed in elemental abundance spectra of dust attracted to permanent-magnet surfaces, suggesting that the magnetite responsible for the magnetization of the dust is actually titanomagnetite. Overall, the dust can be shown to have a saturation magnetization of less than 2 A m2 kg− 1. However, some grains are significantly more magnetic, and by interaction with a permanent magnet it is possible to separate the airborne dust into populations of more and less magnetic grains. Subpopulations attracted to a magnet have been seen to have magnetizations above 7 A m2 kg− 1. The widespread presence of magnetite and other easily oxidized minerals like olivine in rocks and in the global Martian dust imply that the Martian surface has been largely devoid of liquid water for a very long time.