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Deepsea fishing in the Southern Indian Ocean has a relatively recent history relative to other areas of the world for two main reasons.  First, it is distant to the traditional fishing grounds and main markets for higher valued fishes – Europe, North American and the Far East.  Second, its fish resources are not abundant because of the deepness in which fishing must occur: they required development of the technical capacity to exploit the deeper oceans, in depths from 600 – 1200m.

The first major impetus to harvest deepwater fishery resources of the Southern Indian Ocean was by the Soviet Union and started in the 1970s.  They used a variety of gears: Trawls; vertical mechanized lines; bottom longlines and traps.  After the breakup of the Soviet Union in 1991 some fishing continued under the flag of Ukraine.

The distribution of the deep-water species that were targeted was connected wholly or partially with the seamounts, ridges and other bottom features of the area.  The Soviet (Ukrainian) fleet targeted alfonsino (Beryx splendens), rubyfishes (Emmelichthys nitidusand Plagiogeneion rubiginosum) and butterfishes (generally Centrolophus niger and Hyperoglyphe antarctica).  The Soviet (Ukrainian) fishing fleet never targeted orange roughy (Hoplostethus atlanticus) and dories (Oreostomidae) though these species were recorded in research vessel catches.

The first catches by Soviet vessels from the Western Indian Ocean were not reported before 1964 but deepwater catches only started to a significant degree after 1975: no further catches have been reported since 2002.  Responsibility for research and exploration of the Indian Ocean lay with the Southern Scientific Research Institute of Marine Fisheries and Oceanography (YugNIRO) based in Kerch, Ukraine.  All the research work was generally coordinated by the All-Union Scientific Research Institute of Marine Fisheries and Oceanography (VNIRO), before December 1991.

The Soviet deepwater fishery in the Western Indian Ocean focused on alfonsino: 18 054 t was reported as landed form this fishery, though there are grounds for considerable uncertainty as to the accuracy of reported figures.  Two peaks in the catch occurred, the first in 1981 (2524 t) and the second in 1996, of 3079 t.  “Snappers/jobfish nei” were also reported to have been landed in significant quantities (9206 t in total) with peaks in 1974, 1980 and 1996.  This group would have included valuable species such as Etelis spp and Pristopomoides spp, but no details of the catch composition are known.  The Centrolophidae, which would have included butterfishes (Schedophilusspp) and bluenose warehou (Hyperoglyphe antarctica) also figured prominently in their catches.  Altogether 8838 t were recorded landed with peak catches in 1980 (1831 t) and 1992 (Ukraine – 828 t).  Bonnetmouths and rubyfishes were another prominent group among the USSR catch with a total of 6798 t reported.  Peak landings were in 1980 (3252 t) and 1993 (Ukraine 551 t).  The high-value (because it is delicious) armourhead (Pseudopentaceros richardsoni) was also important – total landings of 3031 t, with peaks in 1982 (414 t) and 1999 (Ukraine - 108 t).  With the exception of “Snappers/jobfish nei” these species have remained important in the fishery until today.

Catches of cardinal fish have been minor, a peak of 80 t in 1981 and there is no record of any landings of Oreostomidae or orange roughy (Hoplostethus atlanticus) though the Soviet fishery did not target this last deepwater species that was to be the stimulus for the development for much of the fishery as it has evolved until today.

The Post-USSR Era

The dissolution of the Soviet Union just predated the development in the SIO of the modern deepwater fishery that was to develop along the lines of a technologically complex aimed-trawl fishery.  Aimed trawling for orange roughy and developed in Eastern Australia and New Zealand though the 1980s and there was strong commercial awareness of the close relation between seafloor features (i.e. bottom ridges, knolls, hills, guyots and seamounts) and orange roughy, especially during the winter spawn period.  Several oreo species also occurred in relation to these seafloor features, either independently or in association with orange roughy along with what could be important bycatch species, e.g. armourhead, rubyfish, bluenose warehou, etc. 

By this time the industry in New Zealand and Australia were aware that commercial aggregations of deepwater fishes did not occur in association with every seafloor feature, for reasons that remain unknown. As a consequence, one of SIODFA’s members began an ocean wide bathymetric survey of the main seafloor features of the SIO prior to the start of any commercial fishing in 1995.  Commercial fishing by the one company began in 1998 closely followed by a second.  Then, in 1999, South African vessels returning from the orange roughy fishery that had been finally closed on the South Tasman Rise off Tasmania chanced upon the fishery and ‘the starting gates were open’.

By 2000, 43 boats were participating in the fishery, a number that had increased to 53, flagged to 17 states, by the following year.  Such was the influx of fishing vessels that Fishing New International, in their May 2000 issue referred to “Roughy Bonanza in Indian Ocean”.  This completely unregulated ‘explosion’ of  fishing effort has not hindered by the cancelling of the Indian Ocean Fisheries Commission in 1999 by the Food and Agriculture Organization, the one body that might have shown some management responsibility in what turned into a completely unregulated ‘gold rush’.  This was  to allow the FAO to inaugurate the Indian Ocean Tuna Commission, a birth that left a vacuum for governance of other high-seas fisheries that remained for the following s 12 years.

As in all gold rushes, the losers outnumbered the winners: by 2004 the fleet had declined to 5 vessels, more-or-less the size of the fleet prior the explosion effort in 2000.  Eight months after their first article, in January 2001, the International Fishing News headlined a follow-up article “Fleet Flops on Seamounts: Mountains of Debt in the Indian Ocean”.  Many operators learned that successful deepwater fishing for orange roughy requires more than a surplus vessel and access to financing to put the vessel to sea.

Fleet Size of Fishing Vessels in the Southern Indian Ocean Deepwater High-seas Fishery

Since the implosion of this fishery in the immediate years following its expansion, the fleet size had been stable between 4 and 5 vessels and it is expected that fleet capacity in the deepwater high-seas fishery of the Southern Indian Ocean will be three, and not in excess of four, vessels in 2012.

SIODFA Symbol of a Blue Marlin
SIODFA Mission Statement


Represents the interests of deep-sea fishing operators of the southern Indian Ocean by promoting responsible management of the fisheries of the SIO and the conservation of deep-sea biodiversity.