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COMPARISON OF THE ABUNDANCE, SIZE COMPOSITION AND HABITAT SELECTION OF GIANT CLAMS IN PROTECTED AND EXPLOITED AREAS
Despite
the fact that Giant Clams are protected by Indonesian legislation, they are
continually fished by local communities for food.
They also have commercial advantages, as the Chinese use the adductor
muscle that opens and closes the shell as an aphrodisiac, and the shells of
larger clams are often used for decorative purposes such as holy water fonts and
bird baths. In addition, the fishermen sell the shell of giant clam for
tile and ornaments. The benefits of
fishing this invertebrate has led to a decline in the number of Giant Clams
found in the region.
A
‘no fishing zone’ (NFZ) has been set up on the coral reef that surrounds the
island of Hoga to compare the effects on biodiversity on the coral reef, with
those areas that are left to exploitation by the local communities.
A local community ‘stakeholder’ committee has been set up, with the
main aim being to maintain and improve biodiversity. Data collected in this project can be used to assess what
affect this committee, if any, is having on the coral reef, as part of the
long-term monitoring program of free living and commercially exploited
invertebrates.
·
To assess
the effect of fishing of Giant Clams on the ecosystem by comparing data from
within the NFZ; outside the NFZ but within the stakeholder managed zone; and
outside both the NFZ and stakeholder managed zone.
·
To assess
species diversity in the field.
·
To assess
what economic advantages are gained by the fishing of Giant Clams by local
communities and to what extent they are being fished.
50
metre transects were laid at a total of 6 sites within the three areas to be
studied. The transects were laid at
the reef flat, reef crest and reef slope with three replicates at each site.
Along each transect each Tridacna were measured in length and identified
down to the species level. All
Tridacna were recorded that were within a 2.5 metre distance either side of the
transect line giving a total study area of 250m2
for each transect.
Structured
interviews were held with fishermen from the local communities in Sampela and
Furake. They were interviewed for
information on when Clam fishing took place, how many Clams were caught on
average, whether the Clams were used for subsistence or commercially, and the in
the cases of commercial fishing, fishermen were asked how much the clams were
sold for.
Results
from the study will be fully analysed on return to the UK
A final year
dissertation report will be completed by Nina Peck, University of Birmingham by
May 2003.