Studies of Green turtle (Chelonia mydas) at nesting and foraging grounds Dr. Juanita Joseph Institute of Oceanography and Environment (INOS) Universiti Malaysia Terengganu

Presentation Outline: Long-term tagging and monitoring of green turtles at Chagar Hutang, Redang Island, Terengganu (1993 – 2014) Identification and determination of natal origins of green turtles at foraging grounds throughout Malaysian waters

Project Site of SEATRU (1993 - present) Chagar Hutang Beach Project Site of SEATRU (1993 - present) Project Leader : Dr. Juanita Joseph (2009 – present) Founders: -Prof. Dr Chan Eng Heng (project leader: 1993 – 2009) -Assoc. Prof. Liew Hock Chark (co-project leader 1993-2002)

Declared as Turtle santuaries in 2005: Chagar Hutang Research Station Mak Kepit Mak Simpan Turtle Sanctuaries Declared as Turtle santuaries in 2005: Chagar Hutang, Mak Kepit & Mak Simpan

Redang Island: Serve as nesting grounds Mating areas Foraging ground

Long-term Tagging and Monitoring of Sea Turtles

Sea turtle nests under incubation at Chagar Hutang, Redang Island

of un-hatched eggs to determine hatching success Excavation and analysis of unhatched eggs Nest excavation Hatchling emergence Examining the contents of un-hatched eggs to determine hatching success

Nest recorded at Redang Island: 1993 -2014 Nest Protected:8911 Total nest marketed: 1264 (120,707 eggs) 1993 – 2004: only 77% of eggs were incubated 2005: Gazette as Turtle Sanctuary (100% eggs incubated) Two species of sea turtles: Green turtle & Hawksbill turtle Nesting occurred throughout the year, but during the northeast monsoon (Nov – Jan) monitoring sometimes could not be done due to rough weather. Peak nesting months: May to July

Number of nesters (1993 – 2014) No. of turtle tagged and monitored (1993 -2014): 1711 Some turtles previously tagged in Chagar Hutang, were found nesting at the nearby nesting beaches (Redang), Pulau Perhentian, and Bidong) Major weaknesses: Data sharing is still limited, no speed restriction near the nesting areas

Dead turtles found around Redang Island Cracked on the carapace, suspected hit by boat propellers

Pulau Redang Internesting behaviour of Green turtles (Acoustic and radio telemetry)

Reproductive Data: Mean ±s.d. Range n (clutches) 99.9 88.1 5.3 5.4   Mean ±s.d. Range n (clutches) Adult Females: CCL (cm) CCW (cm) 99.9 88.1 5.3 5.4 78.7 – 115 70 - 104 1975 Hatchlings: SCL (cm) SCW (cm) Weight (g) 4.56 3.41 21.4 0.19 0.32 2.3 3.73 - 5.08 2.01 - 4.24 13.8 - 29.8 604 (34 clutches) 495 (33 clutches) Eggs: Diameter (cm) 3.82 37.2 0.31 4.5 2.79 – 4.98 25.9 – 47.2 270 (27 clutches) 270 (27 Clutches) Clutch size (eggs) 92 21.1 33 - 153 % Hatching success 79.8 23.4 73 - 86 Incubation period (days) 56 4.36 42 - 71 No. of clutches per female 2.1 1 - 12

Internesting interval:

Remigration Interval:

22 years of conservation effort, does the sea turtle population had increased in Redang Island? Long term protection is tedious, but maintaining high hatchlings output is shown to be an effective and essential conservation strategy. Conservation must be sustained for a long time. Funding Field assistants

Volunteer Program: To assist and fund the long-term sea turtle conservation at Redang Island To increase & create public awareness in sea turtle http://seatru.umt.edu.my

Genetics study of sea turtles at foraging grounds

Poaching Incidences Poaching incidences of sea turtles throughout Malaysian waters. November 2003 – 148 dead turtles aboard, few Chinese fishermen intercepted in waters off Labuan, Malaysia. May 2004 – arrested 16 fishermen from Hainan after discovering about 160 dead turtles in their vessel (Pulau Mengalum) June 2005 – more than 100 turtles were seized from a Hainan trawler (Labuan) April 2008 – more than 40 turtles and tortoises were seized from China, Vietnam and Thailand trawlers which were found 120km offshore of Miri, Sarawak, Malaysia.

2007 Poaching Incidences 26 Mac 2007 – 78 turtles found in a fisherman boat, 18 nm Pulau Mantanani, Sabah. 29 Mac 2007 – 240 turtles found in a Hainan fishermen boat, 18 nm from Pulau Mengalum, Sabah.

2014: Pulau Tiga, Balambangan, Kudat Slaughtering of green turtles, more than 50 carcasses were found Suspected that turtle were caught around the areas. Some slaughtered, some sold alive to Chinese and Vietnamese fishermen

Objectives To identify foraging grounds throughout Malaysian waters To determine the natal origin of sea turtles at each foraging grounds in Malaysia using mtDNA control region sequences (which nesting rookeries uses the foraging grounds in Malaysia)

Perhentian Island Redang Island Tanjung Tuan Sungai Pulai Tun Sakaran Marine Parks Mantanani Island   Sempadi Layang-Layang Island South China Sea Celebes Sea Strait of Malacca Sipadan Brunei Bay Pulau Tiga   Redang Sempadi Brunei Bay P.Tiga Mantanani Tg Tuan Sg. Pulai TSMP Sipadan Green Turtle 7 5 47 1 20 3  - 53 37 Hawksbill Turtle - -  2 8 Total 25 11 61 42 Turtles were seen at Perhentian Island & Layang-layang, but we didn’t manage to catch them

Frequency (%) Maturity stages

Methodology 1. Identification of feeding grounds Field Sampling 1. Identification of feeding grounds 2. Turtles captured by snorkelling/SCUBA diving or rodeo. 3. Turtle lifted up to the boat for measurement, tagging and withdrawal of blood samples for genetics study.

Brunei Bay Turtles were captured using ‘kabat’ A total of 47 green turtles were caught Collaboration with SEAFDEC Photos were taken at Brunei Bay (Lawas, Sarawak, Malaysia)

Genetic Results (mtDNA control region sequences) Haplotypes South China Sea Celebes Sea Haplotypes previously identified by: CmP20 (A3) 3 19 Dethmers et al. 2006 CmP77 (A4) 1 CmP49 (C3) 22 CmP87 (C4) 9 CmP40 (C5) 2 4 CmP82 (B5) CmP89 (C8) 5 CmP91 (C14) 8 CmP57 (D2) 24 34 CmP61 (E2) CmP19 (CMTWC) Dutton et al. unpublished CmP32 (FIJF) CmP154 CmP221 New haplotype   n 77 90

Bayesian Mixed-Stock Analysis,MSA (Pella & Masuda 2001) Rookery With uniform prior distribution Weighting by population size   South China Sea Celebes Sea Mean 2.5% 97.5% nGBR 0.16 0.00 1.78 0.05 0.62 0.24 2.55 0.08 0.85 Coral Sea 0.15 1.74 0.61 0.19 2.13 0.07 0.75 sGBR 1.69 0.59 2.21 0.78 New Caledonia 2.15 0.06 0.73 0.18 2.04 0.71 Micronesia 4.52 16.24 17.49 3.17 33.35 4.70 16.42 17.42 3.20 33.56 PNG 1.88 8.05 27.22 0.17 1.89 8.44 27.77 Peninsular Malaysia 2.38 29.53 0.57 7.45 3.64 46.12 9.37 Sarawak 10.89 28.51 0.69 10.78 29.21 0.58 Sulu Sea 14.97 43.94 36.80 64.83 17.78 45.44 40.08 65.63 Berau Island 7.71 78.66 4.84 27.46 8.62 79.74 6.37 29.54 SE Sabah 18.18 83.92 24.80 75.66 11.65 78.29 20.16 72.84 Aru 16.08 36.87 0.79 5.82 16.52 37.82 0.80 5.86 GOC 18.53 47.08 0.94 21.58 48.70 0.11 1.25 Ashmore Reef 0.25 2.84 1.32 18.45 0.26 2.90 22.22 Scott Reef 0.40 4.75 1.73 0.39 4.67 0.14 1.56 West Java 0.70 8.34 2.19 20.27 8.90 21.35 NW Shelf 1.97 0.68 0.30 1.09 Iriomote 0.66 0.60 0.02 0.22 Ishigaki 0.90 0.03 0.29 Ogasawara 1.76 1.65 Wan-an 1.70 1.18 6.47 0.45 0.56 4.85 Lanyu 3.81 43.60 1.20 13.98 1.75 29.94 9.56 Pella J, Masuda M (2001) Bayesian methods for analysis of stock mixtures from genetic characters. Fish Bull 99: 151-167

Bayesian Mixed-Stock Analysis,MSA (Pella & Masuda 2001) Region With uniform prior distribution Weighting by population size   South China Sea Celebes Sea Mean 2.5% 97.5% Western Pacific 5.32 0.00 17.43 25.77 12.42 37.36 5.67 17.97 26.14 11.81 37.91 Indian Ocean and SE Asia 90.27 51.03 99.97 71.67 56.40 85.60 92.27 64.35 99.99 72.61 58.83 87.35 Yaeyama 0.30 3.00 0.13 1.36 1.44 0.05 0.63 Ogasawara 0.15 1.76 0.60 0.14 1.65 0.57 Taiwan 3.96 43.79 2.38 15.29 1.80 30.00 1.15 10.60

South Great Barrier Reef Micronesia Aru West Java GOC Coral Sea South Great Barrier Reef

Conclusions: This study provides new insights into the stock composition and movement of green turtles in the Southeast Asia. Exploitation of sea turtles at foraging grounds in Malaysia will not only affect nesting rookeries in Malaysia, but will also effect nesting rookeries in other countries. Demographic studies of foraging grounds and genetic sampling (for both foraging and nesting rookeries) in Southeast Asia should be continued to monitor temporal variation of sea turtles in this region.

Special Thanks: Jabatan Taman Laut Malaysia Jabatan Perikanan Malaysia Sabah Parks Sabah Wildlife Department Sarawak Forestry Corporation Majlis Keselamatan Negara Research was sponsored by: FRGS (59123) INOS, UMT- HICoE (66928)