Turtle Presentation to MSBC 2009

8/14/2019 Turtle Presentation to MSBC 2009

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A three year review from Playa Norte,Tortuguero, Costa Rica

Stephanny Arroyo Arce , Wing Tsui, Diogo Verissimo, Julie Jackson,James Lewis, David Aneurin Jones and Rebeca Chaverri

Email: [email protected] Vision International Costa Rica,

Apartado Postal 78-7209, Cariari de Pococ, Limn, Costa Rica.

Marine TurtleMonitoring and Conservation

Hand-in-Hand:


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Study Site

Maps: MINAET & googlemaps


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Study Site



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Study Site



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Project AimsGeneral

Conservation

Scientific

Monitor the dynamics of the marine turtle populations of Playa Norte and mitigate theimpact of human activities on their conservation status through filed research, activeoutreach and cooperation with local stakeholders.

Reduce poaching rates by maintaining a presence on the beach and by disguising andrelocating nestsEducate the local community and tourists about marine turtle conservationManage the beach habitat to increase availability of nesting sites

Investigate the impact of development on the marine turtle population

Gather biometric data on nesting marine turtlesRecord the spatial and temporal distribution of nesting activity

Monitor the number of nesting emergencesDetermine the poaching level of nests and turtlesRecord nest survivorship and hatching ratesMonitor the apparent health of nesting femalesTrack re-emergences and migrations between nesting beachesMonitor the impact of tourism on the turtle population


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Work Conducted

Night walks : Nesting Seasons (Mar-Oct)Spatial & temporal distribution of nestsBiometric informationNest markingTagging nesting femalesNest relocation*


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Morning Census : Year RoundRecord new tracks of nesting turtlesErase all tracksCamouflage nestsDetermine the status nest laid in past two days

Work Conducted


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Work Conducted


Morning Census : Year RoundRecord new tracks of nesting turtlesErase all tracksCamouflage nestsDetermine the status nest laid in past two days

Excavations : Hatchling Season (Jun-Dec)


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Habitat Management : Year Round

Educational Classes & Events : Year Round

Work Conducted continued...


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Results

Playa Norte receives up to four speciesof marine turtles


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Leatherback (Dermochelys coriacea)

C R I T I C A L L Y

E N D A N G

E R E D

Photo seaturtle.org


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Green Turtle (Chelonia mydas)

E N D A N G E R

E D

Photo seaturtle.org


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Hawksbill (Eretmochelys imbricata)

C R I T I C A L L Y

E N D A N G

E R E D

Photo seaturtle.org


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Loggerhead* (Caretta caretta)

E N D A N G E R

E D

Photo seaturtle.org

*Incidentally recorded


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Nests 2007-2009

Table 1. Number of nests recorded for 2007 to 2009, Playa Norte, Tortuguero, Costa Rica

NB: All data presented for 2009 is correct until October 7 th

Nesting SeasonSpecies 2007 2008 2009

C. mydas 803 442 154

D. coriacea 50 88 70

E. imbricata 16 27 19


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Temporal distribution:Dermochelys coriacea

Figure 1. Temporal distribution of leatherback nests during the nesting season 2007 to 2009at Playa Norte, Tortuguero, Costa Rica.

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Temporal distribution:Chelonia mydas

Figure 2. Temporal distribution of green nests during the nesting season 2007 to 2009 at PlayaNorte, Tortuguero, Costa Rica .

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2007 2008 2009


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Temporal distribution :

Eremochelys imbricata

Figure 3. Temporal distribution of hawksbill nests during the nesting season 2007 to 2009 atPlaya Norte, Tortuguero, Costa Rica .

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2007 2008 2009


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Encounter times

Figure 4. Peak of activity during the nesting season 2007 to 2009 at Playa Norte, Tortuguero,Costa Rica

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Encounter time

N u m b e r o f t r a c k s

2007 2008 2009


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Tagging

Table 2. Turtles newly tag during the nesting season 2007 to 2009 at Playa Norte,Tortuguero, Costa Rica

Returning address Dept. Biol.UF, Gainesville, FL, USA

Tag Series: Inconel CP0000 & Monel VA0000

Nesting Season

Species 2007 2008 2009

C. mydas 106 79 30

D. coriacea 8 10 11

E. imbricata 4 4 7


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Hatching information

Table 3. Number of hatched nests and hatchlings, 2007-2009, Playa Norte,Tortuguero, Costa Rica

For the nesting season 2008, the success rate for leatherbacks nestswas 75%, for green nests 85%, and for hawksbill nests 64%

SpeciesNumber of hatched

nestsNumber ofhatchlings

C. mydas 254 25,151

D. coriacea 62 2,624

E. imbricata 18 2,203


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Spatial distribution

Figure 5. Spatial distribution of sea turtles during the nesting season 2007 to 2009 at PlayaNorte, Tortuguero, Costa Rica

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Beach sector

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2007 2008 2009


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Nest poaching

Figure 6. Poaching rate of nest after two days that the eggs were laid, during the nestingseason 2007 to 2009 at Playa Norte, Tortuguero, Costa Rica

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Nesting season

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Poached Nest


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Poaching of adult turtles

14 turtle carcasses were recorded2007 3 Cm

2008 6 Cm; 1 Ei2009 4 Cm

(one nested)

18 additional signs of poachingwere recorded (lifted turtles)

2007 3 Cm

2008 8 Cm; 1 Ei2009 6 Cm; 1 Ei

(seven nested)

O i l f d li i h


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On two occasions turtles were found alive in thevegetation during morning census and released

Picture taken from Turning the turtle ; BBC Wildlife, May 2009


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The Future...?


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The Future...?


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The Future...?

--- 14% poachingfrom excavationdata available

until October 7,2009


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Thanks

With financial support from

With institutional support from

Volunteers and staff

Project partner

Documents

Turtle Presentation to MSBC 2009