Coconut Crabs as a Target for Promoting the Establishment of Marine Protected Areas on Green Island, Taiwan

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Coconut Crabs as a Target for Promoting the
Establishment of Marine Protected Areas on Green
Island, Taiwan

• C.P. Chen1,2,3, S.T. Lin2,3, F.L. Wang1
• 1 Institute of Fishery Science, National Taiwan
  University, Taiwan
• 2 Institute of Zoology, Academia Sinica, Taiwan
• 3 Research Center for Biodiversity, Academia
  Sinica, Taiwan

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Local Community
Coconut Crabs
Local empowerment
Conservation
Green Island
Marine Protected Area (MPA)
MPA establishment combining local community and
ecosystem
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Green Island introduction
Green Island

• History
• Ecology
• Coral reef ecosystem
• Hard corals176 spp.
• Soft corals27 spp.
• Fishes602 spp.

Map of Green Island.

• 16.2 km2
• 3200 people
• Mountain peak of
• Green Island is 281m

Photos available at http//green.taitung.gov.tw/ca
ption/ca_page1.asp
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Coconut crab, Birgus latro

• A threatened species, list on the Red list of the
  International Union for the Conservation of
  Nature (IUCN) since 1983
• Protected by the Wildlife Conservation Law in
  Taiwan since 1995.

Birgus latro (Linnaeus, 1767)
Phylum Arthropoda Class Crustacea Order
Decapoda Infraorder Anomura
Family Coenobitidae Genus Birgus
Coconut crab, Birgus latro .
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Life history of the coconut crab, Birgus latro.
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Why we choose coconut crabs as an umbrella
species of Green Island?

• Relationship between coconut crabs and local
  residents
• as childrens pet in early days
• The ecological importance of coconut crabs,
  including
• large body size
• Unique ecological niche
• long life history
• the unique life of this migrating species, as
  adults occur in terrestrial mountain areas
• Successfully conserving the habitat of coconut
  crabs will not only protect the coastal zones and
  nearby waters, but also land areas

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Threats to coconut crabs on Green Island

• Illegal harvesting
• population of coconut crabs declined
  rapidly.
• Too many infrastructures
• harm its habitats and block its spawning
  pathway.
• Environmental deterioration
• habitat fragmentation

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Current tourism state of Green Island
SARS

• Number of tourists visiting
• Green Island from 1991 to 2003
• Carrying capacity
• 2000 persons/day
• (Calculating by ECG international,
• 1993)

• Number of monthly tourists
• from 1991 to 2003
• July is the peak
• Averaged of last five July is
• 64,077 persons

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Three actions for coconut crab conservation

• Basic survey and larval culture of coconut crabs
• Habitat conservation
• Local community empowerment through education

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Basic survey of coconut crabs
Hard to conduct the population survey!
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Capturing female coconut crabs

• Spawning area

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Larval culture of coconut crabs

• Temperature 24-25?
• Salinity 34-35.
• fed with hatched Artemia nauplii

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Larval culture results in 2004
Glaucothoe of coconut crab hiding in a snail
shell.

• 20 Zoea metamorphosed to
• glaucothoes on the 27th to
• 34th day
• 6 carrying the shell on the 37th
• to 43rd days of its zoeal life.

The mean survival rates of zoeae fed with
enriched Artemia nauplii are higher than
unenriched groups in each zoeal stages.
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Habitat conservation

• Maintain habitat diversity

Adults
Juvenile
larva
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Habitat conservation

• Avoid habitat fragmentation

The road circling Green Island, cuts the
migration routes of hermit crabs
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Local community empowerment through education
Framework of the coconut crab conservation team's
works on Green Island.
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Coconut crab conservation team

• Team members including teachers from local
  schools, government officials, police and local
  residents.
• Objectives
• Environmental education
• Stopping illegal harvesting
• Habitat preservation
• Artificial culture
• Information collection
• Ecotourism development

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Environmental education at Green Island
elementary school in 2003.
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Coconut crab booklet, emphasizing the
relationship among coconut crabs and their
natural environments on Green Island.
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(a)
(b)
Coconut crab postcard. (a) The front of the
postcard emphasizes the life history and
habitats, (b) The back of postcard states the law
and punishment.
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Propositions of coconut crabs conservation

• Ecological corridors for crabs.
• Enforcement of conservation laws.
• Promoting environmental education and local
  communication.
• Continuing research on artificial culture
• Protecting the entire habitat of coconut crabs,
  from the mountains to the sea.

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Outlook for the MPA and creation of an Eco-island

• MPA
• MPA proposed emphasizing both ecological and
  social aspects.
• Local participation on the planning and managing
  process of MPA.
• Eco-island
• Conservation actions start from protecting
  coconut crabs.
• Maintain biodiversity, and habitat integrity
• Develop Ecotourism.
• Wise and sustainable use natural resources.

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Thank you
Girl with coconut crab Painted by Y. W. Ou, 1961