Sea Turtle Conservation in Seychelles

Transcription

1 Sea Turtle Conservation in Seychelles by Jeanne A. Mortimer, PhD Presentation made to participants of the Regional Workshop and 4 th Meeting of the WIO-Marine Turtle Task Force Port Elizabeth, South Africa 3-8 December 2012 IOSEA MoU Seychelles: ~150 islands; EEZ = 1,374,00 km 2 Almost every island hosts both nesting & foraging green turtles & hawksbills, but relative numbers of each varies from island to island. 5 Species Occur in Seychelles Green Turtles (Chelonia mydas): nest primarily in the southern islands; forage throughout country Hawksbills (Eretmochelys imbricata) : nest primarily in the Inner Islands & Amirantes; forage throughout country Loggerheads (Caretta caretta): forage Leatherback (Dermochelys coriacea): forage Olive Ridley: forage (first confirmed Seychelles record on 12 Sept 2006) Leatherback sometimes wash ashore dead in Seychelles First Olive Ridley recorded in Seychelles!! 12 Sep 2006 Believed to be by-catch mortality from Long Line Fisheries Remie S, Mortimer JA First records of Olive Ridleys (Lepidochelys olivacea) in Seychelles. Marine Turtle Newsletter 117:9. 1

2 Sea Turtles feature on paper currency & as the Logo for the Central Bank of Seychelles Sea Turtles: an economically important resource for Seychelles Historical Economic Benefits : Meat & Shell (until 1994) Taken primarily from Breeding Adult Turtles Harpooning Breeding Turtles near the Nesting Beach (early 1980s) Turtles were Turned on the Nesting Beach Take of Green Turtles for Calipee for Export to Europe Between 1907 and 1968 (61 years) rtles Killed for Calipee per Year Ave Number Green Tur at least 156,850 turtles killed Green Turtles Killed / Year Years Take of Hawksbill Turtles for Shell for Export to Europe & Japan Between 1894 and 1982 (88 years) at least 81,700 turtles killed Number of Hawksbills Killed Hawksbills Killed Price per Turtle Years Price per Turtle (Rs) Average P 2

3 Hawksbill Shell Curios for Sale near the Clock Tower (~ 1982) Artisan Compensation & Retraining Programme Project (early 1990s): GEF Seychelles Government Activities: Procured all Raw Hawksbill Shell in Possession of Shell Artisans Retrained Shell Artisans and Provided Financial Assistance to Install them in New Professions Once the needs of the shell artisans were addressed, it became politically feasible for Seychelles Government to pass national legislation protecting sea turtles: Miss World 1998 Event Wild Animals (Turtles) Protection Regulations (1994) Reg. 4. Declares turtles & eggs protected throughout Seychelles (1) No person shall disturb, catch, injure, fish for, kill, sell, purchase, receive or possess any turtle. (2) No person shall possess, disturb, sell purchase, receive, take, remove or cause to be taken any turtle egg. Vice President James Michel (now President J. Michel) setting fire to the shell stockpile to demonstrate commitment of Seychelles Gov t to ending trade in Hawksbill Shell Turtles Important for Ecosystem Health Hawksbills prevent over-growth of sponge on coral reefs Green turtles keep sea grass cropped short Modern Economic Benefits : a Tourist Attraction 3

4 Monitoring Programmes for Nesting Turtles Are very effective conservation tools, in that they provide: Scientific data Community awareness through involvement of local people De facto Anti-poaching campaigns Currently some 20 monitoring programmes are operating in Seychelles Population Trends for Hawksbills in Seychelles Documented by data from monitoring programmes Population Increase at protected islands (ex. Aride, Cousin, etc.): But Population Declines at un-protected islands (ex. Mahe, Praslin, La Digue, etc.): Protection of Nesting Beaches is Effective For example: Cousin Island Hawksbills 8-fold increase from 1973 to 2010 (to 250 females/yr) Aldabra Atoll Green Turtles 5t to 8fold ldincrease from 1968 to 2008 (to 16,000 clutches / yr *) * Where saturation tagging is not possible, numbers of clutches may be a better index of population size than numbers of females Four major island groups in Seychelles: Inner islands (granitic); Platte & Coëtivy and Amirantes Group (sand cays); and Southern Islands (mostly upraised limestone reef) Inner Islands: Human Population Centres Inner Islands: Protected Islands Very important nesting sites for hawksbill turtles 99% of Human Population: ~90,000 people Strict Nature Reserves: Aride & Cousin National Parks: Ste. Anne NP, Curieuse NP, Silhouette NP 4

5 Very important nesting sites for hawksbill turtles; tl some green turtle nesting Inner Islands: Private Islands Long term habitat protection guaranteed only at Cousine Island Islands with long term sea turtle monitoring programmes: Aldabra Atoll (Seychelles Islands Foundation) Alphonse/St. Francois & Desroches (Island Conservation Society (ICS) D Arros/St. Joseph (D Arros Research Centre) privately owned Green Turtle (Chelonia mydas): major nesting in the Southern Islands; minor nesting in Amirantes and Inner Islands Hawksbill Turtle (Eretmochelys imbricata): major nesting in the Amirantes and Inner Islands; minor nesting in the Southern Islands 5

6 Satellite Tracking: Hawksbills In 1998, five post-nesting females tracked by satellite from Cousin Island All five satellite tracked turtles remained within borders of Seychelles Bank Long Distance Hawksbill Migrations Satellite Tracking: Green Turtles In 2012, four post-nesting females tracked by satellite from St. Joseph atoll Collaboration between: SWIOFP, Kelonia, IFREMER, D Arros Research Centre Long Distance Green Turtle Migrations In-Water Turtle Studies General Habitat Surveys Conducted nationwide to determine Locations of Critical Habitats Relative abundance of turtles at various sites Assess how coral mortality may be affecting foraging turtle populations 6

7 In-Water Turtle Studies Juveniles on Feeding Habitat Mark Recapture (i.e., Tagging Studies) Growth Rates Aldabra Migrations D Arros / St. Joseph Population structure Sites in Inner Islands Doctoral Thesis: Rainer von Brandis Foraging ecology of hawksbill turtles at D Arros Island. Tshwane University, South Africa. Mark-Recapture of Foraging Hawksbill Turtles at Aldabra Atoll Recapture Site In-water studies in the Outer Islands Tagging Site Recapture Site Mortimer, JA, Gerlach, J, Summerton, P Long Distance Migrations of Hawksbills Tagged as Juveniles at Aldabra Atoll: Confirmation from Digital Photography. Marine Turtle Newsletter. 129: Genetic Studies collaborative: Hawksbills: Nancy Fitzsimmons, University of Canberra, Australia (mtdna: wider Indian Ocean) David Richardson & Karl Phillips, University of East Anglia, UK (micro-satellites: Seychelles nationwide) Green Turtles Jerôme Bourjea, Ifremer, Île de la Reunion, France (WIO) 7

8 Thank you! The organizers of the Regional Workshop and 4 th Meeting of the WIO-Marine Turtle Task Force Especially: Ronel Nel and her team Douglas Hykle, IOSEA Secretariat Nelson Mandela Metropolitan University for providing the venue for the meeting 8