Marine Atlas: Maximizing Benefits for Fiji

include parrotfish (family Scaridae), surgeonfish (family Acanthuridae) and rabbitfish (Siganidae). However, over 100 species are reported in the deep waters off Fiji, and in recent years interest has developed in medusafish (family Centrolophidae, primarily bluenose ( Hyperoglyphe antarctica )), blue warehou ( Seriolella brama ) and alfonsino ( Beryx spp.) on seamounts (see also chapter “Underwater mountains”). Line fishing for these species has been carried out commercially for several decades. Deepwa- ter snapper fishing was promoted in the 1980s by SPC and Fijian fishers were actively engaged in this fishery (Dalzell and Preston, 1992). The fisheries occur on the outer-reef slope and around seamounts (mainly in depths from 100 to 400 me- tres; sea also chapter “Underwater mountains”). The gear used includes hand reels and powered reels, with some commercial bottom longlining and trotlining. A regional assessment of the fisheries potential was made in 1992, largely based on sea- floor area around 200 metres deep. Following this assessment, Fiji’s waters were estimated as having a sustainable yield of between 400 and 1,200 tons per year (SPC, 2013). However, although there have been up to seven licensed vessels fishing off Fiji, such fisheries in the region have struggled as a whole, due to low catch rates following an initial fishing-down phase, variable export markets and prices, and limited habitat area (McCoy, 2010). In 1987, Fiji put management guidelines in place for deepwater snappers, though these have not been updated given the lack of a consistent fishery. In 2011, SPC hosted an international workshop, where it was recommended that biological sampling and studies be undertaken across the Pacific Islands for deepwater snapper and other deepwater dem- ersal fisheries, since these species are believed to be long-lived (20+ years), slow-growing and late to mature, thus making them susceptible to overfishing (Williams et al., 2013). Overfishing, from Fijian and international fishers, in both the inshore and offshore fisheries, is a big concern in Fiji and worldwide, with only 10 per cent of global fish stocks not yet at their limits (see graphic). The tuna catch map shows the general distribution of all tuna catches from 2001 to 2010. All species are widely distributed, though there is limited information on the stock or substock structure. Fishery catches need to be managed on a regional basis, rather than at the national level; albacore tuna is a good example of this. A South Pacific stock is distributed between 10°S and 50°S, spawning between latitudes of 10°S and 25°S (Nikolic et al., 2016). Juveniles occur more in surface waters at higher latitudes compared with adults, which are found in deeper subequatorial wa- ters. Adults appear to have a seasonal migration pat- tern, moving south during early summer (December – January) and north in winter (June – August). Depth and seasonal distribution therefore need to be consid- ered in the spatial management of tuna fisheries. The distribution of tuna and their fisheries is expect- ed to shift with climate change, potentially moving to the east and to higher latitudes (Lehodey et al., 2011). While this is not expected to affect Fiji much at the large spatial scale of the current models, it is a factor that should be considered in longer-term management scenarios. The deepwater fisheries map shows historical catches around Fiji based on FAO data and national reports. As regards the distribution of deepwater snapper, information is also limited. Gomez et al. (2015) estimated the distribution of 14 deepwater snapper

species, using available fisheries and oceanographic data. Depth was the most influential predictor and there were strong regional patterns in the modelled distributions of snapper. Seamount features are recognized as important habitats for deepwater snappers. If there are resident populations of fish on seamounts, it can make them vulnerable to localized overfishing, as well as detrimental impacts from deep-sea mining (Clark et al., 2016). Improved knowledge of stock structure, and the degree of seamount-affinity, are issues of major relevance to management. The likelihood of restricted distribu-

tions of these deepwater species means there is a need to consider regulations specific to seamounts or to localized areas of suitable fish habitat, in order to reduce the risk of serial depletion. Fiji’s offshore fisheries are evidently important, providing economic benefits, employment and food additional to that provided by its valuable inshore fisheries. In order to maintain these values for gener- ations of Fijians to come, MSP and evidence-based, sustainable fisheries management is crucial to preventing us from fishing in the dark.

DEEPWATER FISHERIES CATCH

2001 2010 (metric tonnes) >0 - 50 50 - 200

200 - 400 400 - 800 800 - 1200

Fiji Provisional EEZ Boundary Archipelagic Baseline

100 50

200 km

Sources : Becker et al, 2009; Claus et al, 2016; Sea Around Us, 2017; Smith and Sandwell, 1997. Copyright © MACBIO Map produced by GRID-Arendal

MAXIMIZING BENEFITS FOR FIJI

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