PRESENT STATUS of Silky Shark, Thresher Sharks, Mobulid Rays and Banggai Cardinafish in Indonesia
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Regional Experts Mee1ng on Commercially-Exploited Aqua1c Species: Sharks 16-17 May 2016 , Bangkok, Thailand PRESENT STATUS of Silky shark, Thresher sharks, Mobulid rays and Banggai cardinafish in Indonesia Dharmadi Center for Fisheries Research and Development, Agency of Marine and Fisheries Research and Development, Ministry of Marine Affairs and Fisheries. Jl. Pasir Putih II, Ancol Timur Jakarta 14430 Indonesia •Email: dharmadi.shark.gmail.com Introduction Indonesia as a nation is home to more shark and ray fishing activities than any other and is one of the highest volume exporters of sharks fins in the world (Blaber et al., 2009). Over the past several decades, national shark production in particular has declined by 28,30%, from 63,366 tons in 2000 to 68 366 tonnes in 2014 (DGCF, 2016). 80 000 70 000 60 000 50 000 (Source : DGCF, 2016) 40 000 30 000 Production (t) Production 20 000 10 000 - 76 78 80 82 84 86 88 90 92 94 96 98 00 02 04 06 08 10 12 14 Trend production of sharks based on shark group in 2002-2014. 70 000 Thresher sharks 60 000 Requiem sharks Mackerel sharks 50 000 Hammerhead sharks 40 000 Dogfish sharks 30 000 Productioni (t) 20 000 10 000 - 02 03 04 05 06 07 08 09 10 11 12 13 14 (Source : DGCF, 2016) Trend production of Thresher sharks in 200-2014 70 000 60 000 50 000 40 000 30 000 Production (t) 20 000 10 000 - 02 03 04 05 06 07 08 09 10 11 12 13 14 (Source : DGCF, 2016) Species composition of sharks landed at Cilacap (2015) 1 Alopias pelagicus Pelagic Thresher 967 25.03 2 Alopias superciliosus Bigeye Thresher 674 17.45 3 Isurus oxyrinchus Shortfin Mako 62 1.60 4 Isurus paucus Longfin Mako 36 0.93 C. falciformis was known 5 Carcharhinus falciformis Silky Shark 312 8.08 as the second most 6 Carcharhinus sorrah Spot-tail Shark 780 20.19 7 Carcharhinus brevipinna Spinner Shark 27 0.70 abundant in terms of 8 Carcharhinus Graceful Shark 17 0.44 numbers recorded during amblyrhynchoides study in Indonesia from 9 Carcharhinus plumbeus Sandbar Shark 14 0.36 10 Carcharhinus leucas Bull Shark 1 0.03 2001 to 2006 (White 11 Prionace glauca Blue Shark 115 2.98 2007) 12 Galeocerdo cuvier Tiger Shark 6 0.16 13 Negaprion acutidens Sicklefin Lemon Shark 1 0.03 14 Carcharhinus Silvertip Shark 1 0.03 albimarginatus 15 Sphyrna lewini Scalloped Hammerhead 47 1.22 Pelagic sharks are known 16 Sphyrna mokkaran Great Hammerhead 1 0.03 as one of bycatches in 17 Mustelus cf manazo Sparse-spotted Smoothhound 133 3.44 tuna gillnet fishery, with 18 Lago garricki Longnose Smoothound 5 0.13 19 Heptranchias perlo Sharpnose Sevengill Shark 228 5.90 A. pelagicus, A. 20 Hexanchus griseus Bluntnose Sixgill Shark 1 0.03 superciliosus and C. 21 Squalus sp. 1 Indonesian Greeneye Spurdog 88 2.28 falciformis as the most 22 Squalus sp. 3 Indonesian Shortnose 309 8.00 Spurdog common shark species 23 Squalus sp. E Western Longnose Shark 11 0.28 caught by this type of 24 Deanica f calcea Birdbeak Shark 4 0.10 fishing gear (Fahmi and 25 Centrophorus squamosus Leafscale Gulfer Shark 1 0.03 26 Centrophorus moluccensis Smallfin Gulfer Shark 1 0.03 Dharmadi 2013) 27 Squatina sp. 1 Indonesian Angel Shark 19 0.49 28 Hidrolagus lamures Indonesian Ghost Shark 2 0.05 Thresher sharks Shark LL Tuna LL 22% 3% Tuna GN 75% 300 Alopias superciliosus GN & LL Tuna Alopias pelagicus 298 unit 250 Shark LL 25% 200 Tuna Tuna LL GN 17% 58% 324 unit 150 Catch (t) Catch 100 21 unit 50 19 unit of boats 0 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 PPS Cilacap, 2016 Species composition (by ind) of sharks landed at Tanjung Luar (January-November 2015) Triaenodon obesus Prionace glauca Carcharhinidae Negaprion acutidens Galeocerdo cuvier Carcharhinus sorrah Carcharhinus obscurus Carcharhinus melanopterus Carcharhinus limbatus Carcharhinus falciformis 53% Carcharhinus brevipinna Carcharhinus albimarginatus 0 500 1000 1500 2000 2500 (a) Numbers of each of the five species of mobulid ray recorded at each of the four main landing sites between April 2001 and October 2005. (b) in each month at Tanjung Luar (Lombok) between April 2001 and October 2005 (c) Estimated numbers of each species that would have been landed at Tanjung Luar in each month, assuming that rays were landed daily (White et al., 2006) Length distribution of sharks landed at East Java in 2015 Max Average Min 450 400 350 300 (cm) 250 200 150 100 Total length Total 50 0 Length distribution of sharks landed at Kedonganan-Bali in 2015 Max Average Min 300 250 200 (cm) 150 100 50 Total length length Total 0 Length distribution of sharks landed at Tanjung Luar in 2015 400 Max Average Min 350 (cm) 300 250 200 150 Total length length Total 100 50 0 Mobulidae Manta (M. birostris, M. alfredi) (Fully protected (Men KP, 4/2014) Mobula japanica M. tarapaca M. kuhlii M. thurstoni Manta species Manta birostris Manta alfredi 1. Mobula japanica – spine-tail devil ray ¤ Up to 3.1 meters in width ¤ White ventral surface ¤ Deep-blue to black dorsal surface ¤ Spine at tail base 2. Mobula tarapacana – sickle-fin devil ray ¤Up to 3 meters in width ¤Olive-green dorsal surface 3. Mobula thurstoni – bent-fin devil ray ¤ Up to 2.2 meters in width ¤ Ventral surface is mostly white, with dark shading along anterior margin double curvature ¤ Deep blue-black dorsal surface Mobula japanica 4. Mobula kuhlii 3.1 m width, white shading 1.2 m width, white shading does extends above eye, spine. not extend above eye, no spine. Frequency and production of Mobulidae caught by tuna gillnet in the Indian ocean-South of Java in 2014 Production (ton) Production Total Mobulidae (ind) Weight (t) Frequency (ind) Frequency n=674 ind M.japanica 90 M.tarapacana 80 70 M.thurstoni 60 50 40 Number ofNumber individu 30 20 10 0 Agust'15 Sept'15 Okt'15 Nop'15 Des'15 Jan'16 Feb'16 Monthly catch fluctua1on of Mobula spp landed at Cilacap-Central Java M F n=674 ind M.thurstoni M.tarapacana M.japanica 0 100 200 300 400 500 Number of individu Catch composition based on individu of Mobula spp (male and female) landed at Cilacap in 2015 Average Estimated Annual Mobulid Landings 2001-15 Change 2001-5 Lamakera 2002-6 2007-12 2013-14 vs 2013-14 Mobulids 931 352 229 -75% Manta spp. 605 229 149 -75% Mobula spp. 326 123 80 -75% Tanjung Luar 2001-5 2007-12 2013-14 Change 2001-5 vs 2013-14 Mobulids 2,150 1,003 103 -95% Manta spp. 272 120 14 -95% Mobula spp. 1,023 883 66 -94% M. tarapacana 337 3 -99% M. japanica 518 20 -96% Change Cilacap 2001-5 2006-13 2014 2001-5 vs 2015 2013-15 Mobulids 2,065 924 750 -64% Manta spp. 53 15 -71% Mobula spp. 1,006 367 -63% M. tarapacana 212 48 -77% M. japanica 635 320 155 -75% M. thurstoni 106 0 -100% M. kuhlii 53 0 0 -100% BANGGAI CARDINALFISH Distribution Population (Yahya et al., 2012) which showed that density of recruits and adult tend to decrease between 2009-2011, whereas for the juveniles more abundant in 2012 compared to 2009. Another study was also carried out in 2010 (Kasim et al., 2014) of which result indicated that the population tend to decrease due to heavy collection for trade and microhabitat loss as the local community and also collect other shallow water marine species for consumption (sea urchin and sea anemone). Its population in Banggai Islands was reported at 1.4 million individuals in 2015, of which number is assumed as a result of 42% reduction compared to the population in 2004 (Vagelli, in prep.). The cause of this decline is reported mostly due to heavy collection for aquarium trade. BCF is relatively easy to adapt in other environment that resemble its known original habitat in Banggai. For example, a population in Ambon, reported being introduced in late November 2014, found grow well and expand to a fairly huge number a year after. However, current habitat exploitation practices in Banggai Islands do not support its sustainability. In a normal condition of a wild habitat, this species breed every month in a year, provided its juvenile microhabitat, with acceptable presentation of sea urchin and sea anemone is maintained (Hartati et al 2012; Erdy, pers com). Effective control and monitoring for BCF collection in this native habitat is needed, as well as local communities education, especially on the issue of correct fishery practice to avoid habitat destruction and maintain the microhabitat of this species related to their own sustainability livelihood. Harvest: Yahya et al, (2012) the harvest data from one site in Banggai, i.e Bone Baru, showed that the number was 99,898 and 99,719 individuals in 2010 and 2011. Moore et al., (2012) mentioned that annual harvest had reached 600,000-700,000 individual/year. Tumbak (Manado), Kendari and Luwuk with the number of individuals per month was 10,000, 20,000 and 5,000 respectively (CV. Cahaya Baru, pers.com). In 2015, the harvest of aquaculture in Ambon annually at 19,953 fish with approximate production is 1,600 fish/month. Bali at 20,000 fish per month. The LINI Aquaculture and Training Centre had harvested and sent its first live production to Great Britain in early March this year at a number of 400 individual fishes (Sertori, 2016).