Shark Depredation and Unwanted Bycatch in Pelagic Longline

Appendix 7
South Africa Pelagic Longline
Tuna and Swordfish Fishery:
Industry Practices and Attitudes towards Shark Depredation
and Unwanted Bycatch
Samantha Petersen and Meidad Goren, BirdLife South Africa, Seabirds@birdlife.org.za
A7.1. Introduction
The oceanic and inshore waters surrounding South Africa are
frequented by 36 species of sharks that are classified as threatened,
near-threatened or data-deficient by the IUCN (IUCN redlist).
Nineteen of these species are threatened by either directed fishing
operations or due to bycatch on other fisheries, eight of which longline
bycatch is a known threat. These include the Thresher Shark Alopias
vulpinus, Great Hammerhead S. mokarran, Scalloped Hammerhead
S. lewini, Smooth Hammerhead S. zygaena, Shortfin Mako Isurus
oxyrinchus, Blue Shark Prionace glauca, Porbeagle Shark Lamna nasus
and Crocodile Shark Pseudocarcharias kamoharai. However, little is
known of the scale of this threat in South Africa’s pelagic fishery.
A7.2. Data Sources
Observer data from South Africa flagged vessels, collected and
analyzed from 2000 to 2005, are used for analyses in this study.
Obser-vers were only placed on foreign flagged vessels in 2005 and
thus data only from this year are available for analysis. We conducted
ten interviews all with captains and crew of South African flagged
vessels, as no foreign vessels have been operating in South African
waters since the commencement of this study.
A7.3. History of the Fishery and Effort Trends
The earliest record of a South African domestic pelagic longline fishery
dates back to the early 1960s. This fishery predominantly targeted
Albacore Thunnus alalunga, Southern Bluefin T. maccoyii and Bigeye
T. obesus tunas (Cooper and Ryan, 2005). Effort waned in the domestic
fishery in the mid 1960s, as interest shifted to more lucrative fisheries.
Thereafter, pelagic fishing effort was largely conducted by Japanese
and Taiwanese vessels as part of a bilateral agreement (Fig A7.1).
These Asian vessels set their gear relatively deeply, frequently set
during the day, seldom used lightsticks and primarily targeted
tuna spp. Their fishing effort accounted for 96% of the c. 12
million hooks set annually within the South African EEZ during
1998-2000 (Ryan and Boix-Hinzen, 1998, Ryan et al., 2002).
In 1995 a permit was issued to conduct a joint venture operation
between a South African and Japanese vessel. This joint venture
showed that tuna and swordfish could be profitably exploited in
South African waters. Consequently, the directorate Marine and
Coastal Management issued 30 experimental permits in 1997 to
South African flagged vessels. These vessels set their gear relatively
shallow, used light sticks and set their lines at night and primarily
caught swordfish (Fig. A7.2).
All foreign licences were revoked in 2002. This has resulted in a
smaller and domestic fishery operating in South Africa’s Exclusive
Economic Zone (EEZ) targeting primarily swordfish. However, the
domestic fishery was further developed in 2004 when 50 commercial
fishing rights were made available for allocation (30 tuna and 20
swordfish). Twenty six rights (11 Korean, 2 Philippine and 4 South
African flagged vessels; remaining permits under ship building
contracts) were allocated to vessels fishing for tuna and 17 for those
fishing for swordfish (15 South African, 1 Belize and 1 Australian
flagged vessel) in March 2005. These foreign vessels were operating
under joint venture contracts with South African companies. Their
effort is recorded separately because they operate differently to the
South African vessel as detailed above (Fig. A7.3).
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