Transcript Towards wetland restoration for the "Wetland Three Musketeers”, a

Towards wetland restoration for the "Wetland Three Musketeers”,
a horseshoe crab, a fiddler crab, and a coconut crab
Hwey-Lian Hsieh, Po-Fen Lin, Fang-Lin Wang, Chang-Po Chen
Research Center for Biodiversity, Academia Sinica, Nankang, Taipei,
Taiwan 115, Republic of China
(Fang-Lin Wang, Po-Fen Lin)
Three arthropod species, the horseshoe crab Tachypleus tridentatus, the fiddler crab Uca formosensis, and
the coconut crab Birgus latro, nicknamed here as the "Wetland Three Musketeers”, and which once thrived in the
coastal wetlands of Taiwan, now survive in only a few small restricted areas. Their population declines were
largely due to loss of suitable habitats caused by anthropogenic impacts and/or harvesting pressures from
humans. We have chosen these three species as flagship species and have set up a three-step strategy
advanced from understanding of life histories of these individual species to their habitat maintenance, and the
issue of wise use of wetlands.
(Hwey-Lian Hsieh and Chang-Po Chen)
Uca formosensis: Habitat requirements and public education programs
Investigating sedimentary microhabitats in U. formosensis
 Silt/Clay content: 10~43%
 Total organic carbon and nitrogen content: 0.16~0.4% and
0.01~0.05%
 Water content:15~31%
 pH: 7.9~8.6(neutral to very weal alkaline)
 Depth of the oxidation layer: often > 16~40cm
 Benthic macroinvertebrates: 58.8~1189.0 individuals/m2
(polychetes, insects, and crabs)
Fig. 5 Some records of educational programs to conserve the fiddler crab Uca formosensis.
a, b, Elementary school teachers and students designing and making traps to collect crabs;
c, deployment of traps in the field; d, field observations of fiddler crab habitats; e,
transplantation practice of fiddler crabs because their original shelters will be reclaimed
soon for constructing a municipal swage treatment plant; f, a book written for public
education.
c.
b.
a.
e.
d.
f.
Coconut crab: Larval development and metamorphosis and public education programs
Fig. 1 The wetland Three Musketeer species: the horseshoe crab Tachypleus tridentatus, the fiddler crab
Uca formosensis, and the coconut crab Birgus latro.
Fig. 2 Localities in Taiwan where viable
populations of each flagship species are found.
a.
a.
c.
b.
d.
Table 1 Criteria used to select the Three Musketeer species as flagship species for coastal wetland
conservation in Taiwan.
Significance
Species
Biodiversity
Horseshoe crab
living fossil of 200
Tachypleus tridentatus Million years
Habitats
Socio-economy
● serum serves as
indication of healthy
mud-sand intertidal flat
endotoxin testing
drug
● visional application
of compound eyes
Fiddler crab
Uca formosensis
endemic species of
Taiwan
indication of healthy
not known
high tidal zone on
mud-sand intertidal flat
Coconut crab
Birgus latro
● threatened species
in the IUCN Red
Book
● hermit crab which
does not carry a
shell except at very
early juvenile stage
indication of healthy
Reef island
food source for island
people
Culture and History
Education
● folk medicine
● habitat
● utensil to dip water
conservation
● some places named ● ecotourism
after horseshoe crabs
● shells served as evilrepellent for home
protection
● habitat
endemic species of
Taiwan
conservation
● ecotourism
● worship sacrifice
● habitat
● Chinese geomancy
conservation
● pet animal
● ecotourism
2.5cm
Juvenile crab
without shell
Fig. 6 Morphology and development duration from hatching to the
glaucothoe stage in the coconut crab Birgus latro under laboratory
condition and a scheme depicting natural habitats the coconut crab use
through its life history.
b.
Fig. 7 Newly metamorphosed and shellcarrying coconut crab juvenile in the
laboratory. a: Close-up view; b: crab
crawling on a piece of coral
fragment.
Fig. 8 Some records of educational programs to promote conservation of the
coconut crab Birgus latro. a, b, Public education for elementary school
students and coastal guards; c, organization of a task force to conduct
conservation affairs; d, book and postcard published to raise public awareness.
General strategies planning for wetlands conservation include the following:
(a) To conserve coastal wetlands as protected areas which still maintain sound function, to improve those that have been disturbed,
and to restore those that have been destroyed. By connecting these three types of habitats to form a “Coastal Wetlands
Conservation Greenway” (Hsieh et al. 2004), coastal wetlands conservation can be implemented;
(b) To accelerate studies of the life history and of habitat requirements of each stage of the Three Musketeer species;
(c) To develop and establish sea-farming techniques for ensuring population;
(d) To educate the public to be aware of wise uses of coastal wetlands by developing a multiple use scheme for natural resources.
Wetlands serving as ecotourism and environmental education sites are such wise uses of wetlands services;
(e) To empower local communities and non-profit organizations to actively participate in local wetlands conservation;
(f) To establish a cooperative coalition involving participation from all relevant sectors including local communities, non-profit
organizations, scientists, governmental agencies, and enterprises; and
(g) To promote innovations in ecological engineering for restoring habitats. Ecological engineering is
a practice that incorporates both design and construction with nature;
(h) To establish international cooperation for designating marine protected areas and promoting wetland conservation.
Horseshoe crab: Establishment of a protected area and public education programs
Further work
a.
Fig. 3 Protected area in Kinmen, Taiwan designated
c.
(1) Horseshoe crab: A new nursing ground and juveniles were found in 2005 in Haoumeiliao wetland, Chiayi County. Local
community, tour businessmen, teachers of elementary schools, and local government formed a team to protect and restore
the horseshoe crab and its habitats.
b.
(2) Fiddler crab: To rehabilitate the Uca formosensis habitats and to monitor and evaluate the effects of mangrove removal on
intertidal ecosystems. To enhance local people’s participation in mangrove removal and protection of intertidal flat. To
continue in public education.
d.
e.
for the horseshoe crab Tachypleus tridentatus.
Fig. 4 Some records of educational programs for conserving the horseshoe crab
Tachypleus tridentatus. a~c, Activities for learning about horseshoe crabs; d, brochures
and a book published to raise public awareness; e, visiting horseshoe crab habitats as a
part of ecotourism tours.
(3) Coconut crab: To promote environmental education and local communication through the coconut crab conservation team
work. Ecological corridors for crabs will be built through community-based works including the study of the distribution of
coconut crab population and spawning migration. The research on larval mass cultivation will be continued in 2006. The
study of genetic connectivity of Birgus latro in the Indo-Pacific region will help in strategic planning for coconut crab
conservation.
Reference
Hsieh HL, Chen CP, Lin YY. 2004. Strategic planning for a wetlands conservation greenway along the west coast of Taiwan. Ocean and Coastal
Management 47: 257-272.