11th ICRS Abstract book - Nova Southeastern University

24-33
Transplantation of Porites lutea to Rehabilitate Degraded Coral Reef at Maiton
Island, Phuket, Thailand
Nalinee THONGTHAM* 1
1 Phuket Marine Biological Center, Phuket, Thailand
Porites lutea is among the most common coral species found in Thai waters. Its solid,
hard structure enables it to withstand storms and strong waves. It is also tolerant to heavy
sedimentation, thus it is appropriate to be used as the main structure in rehabilitation of
degraded coral reefs. However, as its growth rate is slower than branching corals, it is
not often used for transplantation. The objective of this study, which began in December
2004, is to determine the survival and growth of different sizes of transplanted P. lutea at
Maiton Island off Phuket, Thailand. Fragments in three different sizes, 4.5x4.5 cm, 3x3
cm and 2x2 cm, were detached from coral colonies and each size was replicated 45 times.
Coral colonies of about the same size as the fragments were also collected for
comparison. The fragments and coral colonies were cemented on concrete blocks and
placed at the same depth as the reef where the corals were taken. Percentage of survival
and detachment, as well as diameter and height of those corals were monitored every 3-4
months for 2 years. Survival of bigger fragments and colonies was higher than the small
ones, which had more tendency (76%) to be detached from the substrate after ninth
months. Mortality of all sizes was between 2 and 17%. Self-attachment of both fragments
and colonies was apparent just after one month, but growth in height was slow. A study
conducted over 10 years in an adjacent area found that it takes at least seven years for the
concrete block to be fully covered and the coral blend with the natural environment. The
study found that P. lutea could be used as the main structure in rehabilitating coral
reefs.
24-34
The Population Of Hard Coral Colonies Growing On Ecoreefs® Artificial Modules
On Manado Tua Island, Bunaken National Park, North Sulawesi, Indonesia
Tries RAZAK* 1
1 Research Consultant, EcoReefs Project at Bunaken National Park, Bandung, Indonesia
Bunaken National Park in North Sulawesi was established as a marine national park in
October 1991 and is one of Indonesia’s most well-known marine ecotourism and diving
destinations. Unfortunately, many reef areas within the park have been decimated into
fields of coral rubble from dynamite fishing that peaked around 30 to 40 years ago. A
rehabilitation program was then implemented in December 2003 where 620 EcoReefs®
modules were installed on a blast-damaged sloping reef area. In the present study,
“returned” populations of hard corals were examined within two-and-half (June 2006)
and three years (December 2006) after the installation. On the first trip, 138 modules
were examined and a total of 5626 colonies belonging to 31 genera in 15 families were
found. The second research trip was performed six months after the first one (December
2006) where 112 modules were studied; the same 112 modules studied on the first trip.
Hard coral population on EcoReefs® modules was dominated by family Pocilloporidae,
Acroporidae, Milleporidae and Poritidae; that altogether covered 91.4% (June 2006) and
85.4% (December 2006) of the total population. The number of corals per module
ranging between seven to 122 colonies; and there was an increase in the average
abundance with 45 colonies/module in December 2006 compare to 12 colonies/module
(July 2004) and 41 colonies/module (June 2006). In regards to colonies' physical
condition, up to 62.1% (December 2006) of the total population were alive and healthy;
this number was higher in June 2006 with 77.6%. The remaining of the population
(37.9% and 22.4% respectively) were dead colonies covered with algae/crustose coralline
algae/sponge, bleached or infected by diseases. These findings showed that artificial reefs
can be used as a catalyst in resurrecting marine life, still conserving the live reef
ecosystems are easier and cheaper.
Oral Mini-Symposium 24: Reef Restoration
24-35
Eco-Block As A Coral-Friendly Contrivance in Port Construction
Hidekazu YAMAMOTO* 1 , Norikazu MAEKOUCHI 2 , Takashi ANO 2 , Megumi OOGI 2 ,
Syuichi TSUDA 2 , Kazuo KURITA 3
1 Coastal Environment Department, ECOH Corporation, Taito-ku, Japan, 2 Okinawa General
Bureau, Cabinet office, Naha City, Japan, 3 Okinawa General Bureau, Cabinet office, Miyako
City, Japan
We confirmed the natural attachment of coral colonies on breakwaters in Naha Port, Okinawa
Prefecture in 1989. Having fixed 30 quadrates to the breakwaters, we have been monitoring the
growth of corals every year since 1990. The results complied until 2003 were reported by Ooka
et al. (2006).
Focusing on this phenomenon as a clue to afford a coral-friendly approach in port construction,
we began the development of technology to enhance coral recruitment and growth on concrete
armor blocks. The development concept centered on creating roughness on conventionally
smooth block surfaces, thus imitating natural substrates as near as possible. The primary
experiment began in Naha Port in 1990, followed by the second one in 1991. The findings from
these experiments were then applied in the project of the Eco-block in 1999, a wave-dissipating
block with abrasive protrusions on its surface. Since the installation of Eco-blocks in 1999, the
growth and recruitment of corals on them have been monitored yearly in 36 fixed quadrates.
With information obtained here, a similar attempt is underway in Hirara Port in Miyako Island.
The surfaces of armor blocks were unevenly processed before their deployment to breakwaters,
and their effectiveness has been continually monitored.
Eco-blocks with abrasions at depths of about 5mm and 10mm showed a greater effectiveness in
coral settlement. The initial coral recruitment was found to be higher at depths of C.D.L. 5m
and shallower. The same results were obtained from the experiment in Hirara Port.
Ooka, S. et al. (2006) Growth of coral assemblages on artificial structures and surrounding
natural substrates. Proc. 10th Int. Coral Reef Symposium, Naha., p.91-98.
24-36
Benthic And Fish Community Succession After The 2005 Red Tide Disturbance in The
Eastern Gulf Of Mexico: Are Artificial Reefs Effective Mitigation Tools?
Jennifer DUPONT* 1 , Pamela HALLOCK 1 , Walter JAAP 2
1 College of Marine Science, University of South Florida, Saint Petersburg, FL, 2 Lithophyte
Research, Saint Petersburg, FL
A harmful algal bloom (red tide) and associated anoxic/hypoxic event in 2005 resulted in
massive fish kills and the collapse of epibenthic communities in depths less than 25 meters
along the central west Florida shelf. An ongoing monitoring study provided a focused time
series (2005 to 2007) of community successional stages at two natural hardbottom ledge sites
and six artificial reef sites, situated in comparable depths (~20 meters), allowing us to assess the
potential use of artificial reefs as benthic invertebrate and fish recruitment/recovery tools during
future disturbances. Radical changes in community structure were observed at both the artificial
and natural habitats after the red tide. Epibenthic invertebrate and fish diversities and
abundances were significantly lower (t-tests: p10 cm) colonies were recorded. Juvenile recruits were abundant on
exposed substrate during post-disturbance samplings. Artificial reefs had much lower benthic
diversities and were dominated by smaller Cladocora arbuscula and Phyllangia americana
corals. Fish community diversities and abundances were higher at the artificial reef habitats.
Successional stages tended to follow a predictable progression and revert to a pre-red tide state,
corroborating previous predictions that the fluctuating nature of the shallow eastern Gulf of
Mexico may limit the effective species pool of colonists. Artificial reefs appear to be
significantly more effective in recruiting diverse and abundant fish populations, with less
diverse benthic invertebrate communities, when compared to natural reef ledges along the West
Florida Shelf.
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