Pacific Island Fisheries and Interactions with Marine Mammals, Seabirds and Sea Turtles Lindsay Aylesworth Duke University Marine Lab, Beaufort, NC

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1 Pacific Island Fisheries and Interactions with Marine Mammals, Seabirds and Sea Turtles Lindsay Aylesworth Duke University Marine Lab, Beaufort, NC Bycatch, the accidental capture of non-target species in fisheries, is a major unintentional impact of fisheries worldwide. Long lived species such as sea turtles, marine mammals and seabirds can be especially vulnerable to bycatch (Beverly 2007, Black 2007, Miller 2007). Project GloBAL, based out of the Duke University Marine Lab has assessed the impact of fisheries bycatch on marine mammals, seabirds and sea turtles worldwide, working toward the larger goal of reducing fisheries bycatch of these vulnerable species and promoting sustainable fisheries. Bycatch for the remainder of this report will be used to refer to any unintentional catch of seabirds, marine mammals, or sea turtles (Project GloBAL 2008). This report synthesizes the existing information relating to fisheries and bycatch at a regional scale in the Pacific Islands. First the bycatch species will be discussed followed by a characterization of Pacific Island fisheries. Bycatch studies, management and recommendations will also be discussed. The study area includes 22 Pacific Island countries and territories including Papua New Guinea, but excluding Australia, New Zealand and Hawaii. An extensive literature review, fisheries observation data and regional experts were used to gather information in relation to Pacific Island fisheries and interactions with long-lived species. Bycatch Species The Pacific Island countries and territories cover over 300 million sq km of the largest ocean in the world (Bleakely 2004). There are 45 reported marine mammal species in the Pacific Islands including 9 mysticetes, 35 odontocetes, and 1 sirenian (IUCN 2008). Of the odontocetes, there twenty different delphinid species. Dugongs are known in the Solomon Islands, New Caledonia, Vanuatu, PNG, and Palau (SPREP 2007). The Solomon Islands and the Cook Islands have the highest reported number of species present with 23. Tokelau has the least number of recorded marine mammals with only 4. Despite efforts in certain areas and on several species, e.g., humpback whales, detailed knowledge of marine mammals such as population estimates, migration paths and important habitats, is at best extremely limited (Miller 2007). This is in part due to

2 limited resources and expertise to undertake research in the region, the vastness of the region itself and the diversity of marine mammals in it (Miller 2007). Sixty-six species of seabirds are known to inhabit the tropical Pacific Islands (Birdlife 2009). French Polynesia has the most reported seabird species with 45; the Cook Islands also have a high reported diversity with 41 seabird species. Nauru has the least number of reported species with one. Guam is an interesting case study because up until the early 1990 s it had 10 reported seabird species. Then an invasive rat species became decimated the seabird population leading to the current situation of no known seabirds in Guam. There are only six countries in the South Pacific with active bird research- Fiji, French Polynesia, Cook Islands, New Caledonia, Palau, and Samoa; these are also the countries with the highest reported seabird species in the Pacific Islands (Birdlife 2009). It is unknown if the other islands also have high seabird diversity but lack the research and resources to fully investigate seabird diversity. There are six types of turtle species found in the Oceania region: the leatherback (Dermochelys coriacea), green (Chelonia mydas), hawksbill (Eretmochelys imbricata), loggerhead (Caretta caretta), olive ridley (Lepidochelys olivacea) and flatback (Natator depressus) (SPREP 2007). The green and hawksbill turtles are the most widely recorded species, with confirmed records in nearly all countries and territories (SPREP 2007). Vanuatu and Papua New Guinea have reported all six species of sea turtles found in their waters whereas Nauru and Wallis and Futuna have only one reported species. Pacific Island Fisheries The fisheries in the Pacific Islands can be broken down into three main categories- commercial, subsistence and traditional. Tuna is the most important commercial fishery with four target species (albacore, bigeye, skipjack, and yellowfin) and four distinct gear types (purse seine, longline, pole and line, and trollers) (Gillett, 2008). There are around 500 purse seiners and 5,000 longline vessels actively fishing for tuna in the region (Gillett 2008). Most of these vessels are from distant water fishing nations and the vessels from the Pacific Islands themselves make up a very small portion of the fleet. Other commercial fisheries in the region include swordfish, deep-water snapper, aquarium trade, PNG shrimp trawl and a PNG shark longline (Adams 1995). Subsistence fisheries occur in all Pacific Islands mostly involving inshore resources to

3 provide sustenance and protein for local diets. There are no estimates for annual catch rates or participation for subsistence fisheries at a regional level. Known gear types for subsistence fisheries include gillnets, traps, handlines, cast nets, reef gleaning and trolling (Adams 1995). Traditional fisheries occur in the Pacific Islands for dolphins (Solomon Islands), dugongs, sea turtles and seabirds. These species are used in celebrations, religious ceremonies, and feasts. Estimates of annual catch rates in these fisheries at a regional level are unknown. Bycatch Studies There have not been many bycatch studies on Pacific Island fisheries. The majority (four) has been written for the commercial tuna fishery (Bailey 1996, Lawson 2001, Molony 2005, Molony 2007). The only other commercial fisheries with the potential for bycatch are the shrimp trawl and shark longline fisheries in PNG and the regional swordfish fishery (Gillett, 2006), but there are no studies of bycatch in these fisheries. The subsistence and artisanal fisheries located inshore are largely unregulated with little to no monitoring of catch or effort. Bycatch would be extremely difficult to monitor in these fisheries as seabirds, turtles and even some marine mammals are consumed traditionally throughout the Pacific Islands and any unintentional catch would be retained and consumed. There is little information on marine mammal bycatch in the Pacific Islands. The most information is from the commercial tuna fishery. In the latest review of observer data there is an estimated annual mortality of 265 marine mammals from longline gear and 10 marine mammals from purse seine gear (Molony 2007). Observer data from the newly established American Samoa observer program has indicated that rough toothed dolphins and false killer whales are known to interact with longlines in the commercial tuna fishery. This further supports complaint from fishermen regarding depredation of catch by toothed whales are common especially in Samoa, Fiji, Tonga, and PNG. Only two examples of entanglement in longlines have been noted in the region, one from a pilot whale in longline gear in Tonga and one from New Caledonia (SPREP 2007). Dugongs are known as bycatch in the barramundi gillnet fishery in Papua New Guinea (Kare 1995) but no mortality estimates have been made. The ban on driftnet fishing mitigated much known interaction between marine mammals and gear targeting albacore

4 tuna in the mid 1990 s (Richards 1994). The most information on bycatch of sea turtles is from the commercial tuna fishery. The latest study estimates that around 900 sea turtles are killed in the longline fishery and 500 in the purse seine fishery each year (Molony 2007). Of those estimates in the longline fishery, 21% are olive ridleys, 17% are green turtles and 10% are leatherbacks; all other turtles are not identified to species level (Molony 2007). Similarly, a study of observer data from the Secretariat of the Pacific Community (SPC) 2001 estimated different rates for turtle encounters based on setting strategies, bait used, and fleet characteristics with rates varying from to turtles per 1000 hooks (Lawson 2001). There was no information on sea turtle bycatch in the PNG shrimp trawl fishery or the PNG shark longline fishery. No information on the use of gillnets in coastal areas and interactions with sea turtles are known in the Pacific Islands most likely due to the fact that Pacific Islanders would not consider this bycatch due to traditional use of sea turtles. The main challenge to identifying and quantifying bycatch of sea turtles is the lack of observer coverage. Lack of observer coverage across the tuna fleet regionally and in each country remains problematic in quantifying sea turtle bycatch throughout the region. Seabird research in the Pacific Islands has not focused on fisheries interactions and therefore the majority of data on interactions is from fisheries observers. Logbook data, observer data, and industry opinion all support the same conclusion, seabird interactions with longline fisheries are rare (Watling 2006). Data spanning the time period from , covering 2,403 sets recorded only eight seabird interactions (Watling 2006). The number of known and potentially vulnerable bycatch species in the region is 11 (of which six are Pacific residents and five migrants), a stark contrast to the 36 known bycatch species at higher latitudes in the South Pacific (Watling 2006). The latest annual estimate for seabird mortality in the regional longline fishery is around 100 seabirds (Molony 2007). Management The Western and Central Pacific Fisheries Commission (WCPFC) manages the commercial tuna fishery and is a regional management organization. All other commercial, subsistence and traditional fisheries are managed at the country level and

5 effectiveness, data collection and sustainability vary by country. The WCPFC has a bycatch specialist working group that focuses on mitigating fisheries interactions with seabirds and sea turtles (WCPFC 2008). All mitigation methods for longlines and sea turtles such as circle hooks, line cutters, dip nets, and de-hookers are now mandatory on all commercial longline vessels (WCPFC 2008). The only mandatory measures for seabird mitigation apply to longlines fishing south of 30 S latitude and North of 23 N latitude and most of the fishing for tuna occurs in tropical latitudes (WCPFC 2008). Therefore the mitigation methods are not mandatory for the majority of Pacific Island exclusive economic zones. Currently there are no measures relating to marine mammals. The Secretariat of the Pacific Community Oceanic Fisheries Programme and Western and Central Pacific Fisheries Commission (WCPFC) produced a marine species identification manual for horizontal longline fishermen to use to assist in bycatch identification. These two organizations in conjunction with several other partners have also produced educational pamphlets on the avoidance of bycatch with longlines and there have been several training workshops related to bycatch around the region. Recommendations Recommendations for bycatch in Pacific Island fisheries are dependent on priorities due to limited funding and resources. If species conservation is the top priority, efforts should be made to mitigate other threats such as invasive species and habitat destruction. If a regional priority is to mitigate bycatch in Pacific Island fisheries the most important action to be taken is to increase observer coverage in the commercial tuna fishery. Coverage on the tuna fleet is estimated to be around 0.77% (Gillett 2008). If observer coverage increased to 5%, the region would have the largest observer coverage in the world (Gillett, pers, comm.). Efforts should be made to increase regional and national observer programmes. The increasing commercial swordfish fishery should also be targeted for observers because it uses shallow set longlines, which are known for high interactions with bycatch species. Each country has a national tuna management plan and bycatch language should be written in to raise awareness of the issue at the national level. More population level information on bycatch species is needed to determine how interactions may affect different species. The final recommendation is for mandatory workshops for commercial vessel owners on bycatch, as part of a licensing condition to

6 fish for tuna in the Pacific Islands. This would increase awareness with the people whose actions directly relate to bycatch because without a change in behavior at this level, bycatch in commercial fisheries will continue. References Adams, T., A. H. Richards, et al. (1995). Research on Fisheries in the Pacific Islands Region. Joint FFA/SPC Workshop on the Management of South Pacific Inshore Fisheries. Noumea, New Caledonia, South Pacific Commission Fisheries Programme. Bailey, K., Williams, Peter G, et al. (1996). By-Catch and Discards in Western Pacific Tuna Fisheries: A Review of SPC Data Holdings and Literature. Noumea, New Caledonia, South Pacific Commission: Beverly, S. and L. Chapman (2007). Interactions Between Sea Turtles and Pelagic Longline Fisheries. Third Regular Session. S. Committee. Honolulu, Hawaii, USA, Western and Central Pacific Fisheries Commission: 79. Birdlife Birdlife International online World Bird Database: the site for bird conservation. Version 2.1. Cambridge, UK: Birdlife International. [accessed 1 January 2009] Black, A., C. Small, et al. (2007). Recording Seabird Bycatch in Longline Observer Programs. Honolulu, Hawaii, USA, Western and Central Pacific Fisheries Commission: 11. Bleakley, Christopher Review of critical marine habitats and species in the Pacific Islands Region. International Waters Project. Apia, Samoa. SPREP, p. Gillett, Robert Tuna for Tomorrow? Some of the Science Behind an Important Fishery in the Pacific Islands. A Report for RETA 6128: Alternative Negotiating Arragements to Increase Fisheries Revenues in the Pacific. IUCN IUCN Red List of Threatened Species. < [accessed 10 November 2008] Kare, B.D A Review on the Research and Fisheries of Barramundi, Reef Fish, Dugongs, Turtles and Spanish Mackerel in the Papua New Guinea Side of the Torres Strait. in Joint FFA/SPC Workshop on the Management of South Pacific Inshore Fisheries. Noumea, New Caledonia. 22 p. Lawson, T. A. (2001). Observer data held by the oceanic fisheries programme covering tuna fishery bycatches in the western and central pacific ocean. Standing Committee on Tuna and Billfish. SPC. Noumea, New Caledonia, SPC OFP: 42. Molony, B. (2005). Estimates of catches and mortalities of seabirds, mammals, sharks and turtles in longline fisheries of the western and central Pacific Ocean, S. O. F. Programme. Noumea, New Caledonia, SPC: 70. Molony, B. (2007). Overview of purse-seine and longline bycatch issues in the western and central Pacific Ocean. Asia and Pacific Islands Bycatch Consortium. S. O. F. Programme. Noumea, New Caledonia, SPC 42 Project GloBAL Tackling the Global Problem of Fisheries Bycatch. < [accessed 2 November 2008] Richards, A. H. (1994). "Problems of Drift-Net Fisheries in the South Pacific." Marine Pollution Bulletin 29(1-3): SPREP (2007). Secretariat of the Pacific Regional Environment Programme Pacific Islands Regional Marine Species Programme Apia, Samoa, SPREP: 48 Watling, D. (2006). Interactions Between Seabirds and Pacific Islands Fisheries, Particularly the Tuna Fisheries. Second Regular Session. S. Committee. Manila, Philippines, Western and Central Pacific Fisheries Commission: 38 WCPFC (2008). Western and Central Pacific Fisheries Commission Tuna Fishery Yearbook Noumea, New Caledonia, Western and Central Pacific Fisheries Commission.