Marine Atlas: Maximizing Benefits for Tonga

NATURE’S HOTSPOTS: KEY BIODIVERSITY AREAS Tongan waters host a large variety of habitats, which are important breeding or feeding grounds for a number of ma- rine and seabird species. The characteristics of Key Biodiversity Areas (KBAs) mapped here can support the further development of management options to balance human needs and protect vulnerable species and ecosystems.

Marine conservation in Tonga is guided by the goals and objectives laid out in its Environment Management Act (2010) and an earlier National Bi- odiversity Strategy and Action Plan (2006). These link national action with more global and regional initiatives such as the Convention on Biological Diversity (CBD) process for designating Ecologi- cally or Biologically Significant Areas (EBSAs), the IUCN’s KBAs and Birdlife International’s Important Bird Areas (IBAs). These areas are defined as sites that contribute significantly to regional or global persistence of biodiversity and consider attrib- utes such as uniqueness or rarity; importance for life-history stages of key species; threatened, endangered or declining species; vulnerability to, or slow recovery from, disturbance; productivity; diversity and/or naturalness. These definitions can operate at all levels of biodiversity (genetic, spe- cies, ecosystem). There is growing recognition worldwide that ma- rine ecosystems need to be managed to prevent or minimize harm from human activities. Con- servation areas or plans can benefit a country’s tourism potential, as well as improving consumer acceptance of products if they are proven to be sustainable. Whale-based tourism is already an important source of income in the winter season. As knowledge of the characteristics of such pro- spective areas develops, they can become critical elements of an integrated protected area network that ensures key ecological sites are protected, while still allowing human activities to occur in an environmentally sustainable way. The map shows the distribution of EBSAs and KBAs in island and offshore areas of Tonga, although it should be noted that there are also a number of localized coastal marine protected areas (MPAs) that are not included on the map. In November 2011, the Secretariat of the Con- vention on Biological Diversity hosted a regional workshop to facilitate the description of EBSAs for the western South Pacific Ocean (CBD, 2012). Two EBSAs were subsequently approved by the CBD: 1) The Tongan Archipelago is a large EBSA en- compassing the central waters of the provisional Tongan EEZ. It covers diverse topography, with shallower waters around the islands, seamounts (e.g. Capricorn seamount) and peaks along the Tonga Ridge, and most notably the Tonga Trench,

Island, Ata Island Marine, Eua Island, Fonualei, Fonualei Marine, Hunga Ha’apai-Hunga Tonga islands, Late, Maninita-Taula-Lualoli, Niuafo’ou, Tofua-Kao and Vava’u Marine EBSAs and KBAs have no official management status, but are components of efforts by the CBD and IUCN to identify species that should be prioritized for con- servation based on their ecological roles, cultural significance, uniqueness (e.g. endemics) and rarity (e.g. threat status on IUCN Red List), and to describe the marine habitats in which these species are likely to be found, and which may therefore need protection. In conjunction with the 10 official marine reserves and protected areas, KBAs and EBSAs can help develop an appropriate network of multiple-use managed areas.

which at its deepest point (Horizon Deep), is 10,880 metres. The region is a key breeding location for the Oceania population of humpback whales. It also supports globally significant pop- ulations of eight seabird species and is generally important for seabird nesting and foraging. 2) Monowai Seamount comprises an active vol- canic cone with a large caldera that has extensive areas of hydrothermal vents at depths of 1,200 metres. These host localized mussel, tubeworm, shrimp and crab species that are found in the venting areas. There are four significant IBAs in Tonga: the largest is the Fonualei Marine Area (15,887 km 2 ), which is an important breeding site for sooty terns; Vava’u Marine is a black noddy breeding location; Late Island hosts a breeding black noddy population; and Ata Island is a breeding site for wedge-tailed shearwater, red-footed booby and brown booby (Birdlife International, 2018a). There are 11 recognized KBAs in Tongan waters (Birdlife International, 2018b), including the above IBAs, and these are listed largely because of their potential importance for seabird species. ‘Ata

Tonga’s KBAs are important habitats, e.g. for bird nesting, and benthic and pelagic species.

MAXIMIZING BENEFITS FOR TONGA

HABITAT VALUES

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