11th ICRS Abstract book - Nova Southeastern University

24-1
Fates Of Restored Acropora Palmata Fragments At The M/v Fortuna Reefer
Grounding Site, Mona Island Puerto Rico: Lessons Learned Over 10 Years
Andrew BRUCKNER 1 , Ron HILL 2 , Robin BRUCKNER* 3
1 NOAA Coral Reef Conservation Program, NOAA, Silver Spring, MD, 2 Southeast
Fishery Science Center, NOAA Fisheries, Galveston, TX, 3 Office of Habitat
Conservation, NOAA Restoration Center, Silver Spring, MD
Restoration of detached Acropora palmata fragments generated by the M/V Fortuna
Reefer grounding off Mona Island (18°02'N; 67°51'W) was completed on October 14,
1997, three months after the grounding. Fragments (n= 1857) were secured to either reef
substrates or dead standing A. palmata skeletons using stainless steel wire. Fragments
experienced high rates of early mortality (57% surviving after 2 years) primarily
attributed to wire breakage and removal during winter storms, overgrowth by bioeroding
(clionid) sponges, disease, and predation by Coralliophila abbreviata (gastropods). Fewer
than 10% (n=166) of the fragments were alive after 10 years. Most survivors resembled
adult colonies with tissue covering their upper skeletal surfaces, extensive branching
(mean= 5 branches, 89 cm in length), and a substantial increase in height (mean = 39 cm
tall). Survivors included representatives of all size classes originally attached (15-340
cm), although the mean length of survivors (78 cm) was significantly larger than dead
fragments (62 cm). Most surviving fragments were secured to the reef (70%) and oriented
upright (>80%). These were 13% larger (mean=79 cm original length; current length=
120 cm) and had grown upward 14% more than fragments attached to skeletons. The
most significant ongoing sources of mortality include snail predation (8%), overgrowth
by sponges (6%), and disease (6%). While some fragment mortality can be directly
attributed to the restoration approaches used at this site, most losses were due to disease
and corallivory, two pervasive problems affecting acroporids throughout the region.
Since 2001, we have documented an increase in corallivore abundance and a severe
outbreak of disease; these primarily affected unrestored colonies, and have caused the
loss of >95% of the colonies in surrounding areas. To improve our ability to recover and
rebuild degraded acroporid populations, restoration approaches need to be combined with
measures to mitigate disease and corallivory.
24-2
Gardening Coral Reefs – New Insights For Coral Reef Restoration By Using
Branching Corals As Ecosystem Engineering Species
Yael HOROSZOWSKI* 1,2 , Jean-Claude BRETHES 3 , Baruch RINKEVICH 1
1 National Institute of Oceanography, Israel Oceanographic & Limnological Research,
Haifa, Israel, 2 ISMER, Universite du Quebec a Rimouski, Rimouski (Quebec), Canada,
3 ISMER, Universite du Quebec a Rimouski, Rimouski (Quebec), QC, Canada
Many of the world’s coral reefs are experiencing a severe degradation due to
anthropogenic activities that have significantly weakened the reefs’ ability to cope with
disturbances. Due to the ineffectiveness of traditional measures, active restoration has
now become the premiere method of rehabilitation. In past efforts, coral colonies were
taken from healthy localities and transplanted into denuded areas. This, however, resulted
in low survival rates and inflicted stress on donor colonies. With the aim of overcoming
these pitfalls, we tested the application of the “gardening coral reefs concept,” a method
inspired from forest restoration guidelines. This method involves generating and farming
large stocks of new coral colonies in an in situ, floating nursery prior to their
transplantation into degraded reefs.
The experiment targeted a degraded zone of Eilat’s Reef, Israel. Two transplantation
events were carried out: In November 2005, 550 nursery-grown colonies of two
branching scleractinians (Stylophora pistillata, Pocillopora damicornis) were
transplanted on five denuded knolls. In May 2007, 330 nursery-grown colonies of three
branching species (S. pistillata, P. damicornis, Acropora sp.), one massive species (Favia
favus) and one hydrozoan (Millepora dichotoma) were added.
The first two years of monitoring revealed low mortality rates of the new transplants. The
new ecological and spatial niches resulting from the autogenic engineering characteristics
of the transplants were immediately colonized by coral-obligatory invertebrates. When
following influences on local fish community we witnessed an increase in the habitat’s
carrying capacity, reflected by higher fish abundance with no modification of the species
composition. S. pistillata colonies from both transplantations released planula larvae.
Thus, the nursery-grown transplants are not only reinforcing the local coral community
but are also contributing to larval pool by participating in the local coral reproduction.
Oral Mini-Symposium 24: Reef Restoration
24-3
Coral Transplantation in a Degraded Lagoon Environment: Differential Results of Three
Species
Edgardo GOMEZ* 1 , Patrick CABAITAN 1 , Helen YAP 1
1 The Marine Science Institute, University of the Philippines, Quezon City, Philippines
A major challenge to restoration ecologists concerning reef corals is the determination of the
appropriate species to use, and how to deploy them in the field to ensure good survival and
growth. We transplanted three coral species which represent different life history strategies,
viz., Montipora digitata, Porites cylindrica, and Pavona danai. Our study aims to establish
viable coral populations within a range of conditions in a degraded lagoon environment
(Bolinao, northwestern Philippines). The basic assumption is that prevailing environmental
factors are still favorable for scleractinian survival, growth and reproduction, but that
limitations probably exist in terms of potential recruitment, substrate suitability, and
competition with other, established, benthic species. Degraded bommies along a gradient from
sheltered to exposed conditions were used as platforms for the transplantation of branch
fragments of the three species mentioned above. There was variable success ranging from high
mortality for a usually fragmenting species, M. digitata, to virtually no mortality for P.
cylindrica, with P. danai towards the more positive end. Growth of the transplants appeared to
be better in environments that resembled more closely those of their naturally established
(source) populations. The experimental treatments included variations in density and
orientation of the transplants (attachment to horizontal and vertical surfaces), for which there
appear to be no statistically significant differences in terms of growth and survival.
24-4
Coral Transplants As Rubble Stabilizers: A Technique To Restore And Mitigate
Damaged Reefs
Pablo ROJAS* 1 , Laurie RAYMUNDO 1 , Roxanna MYERS 1
1 Marine Laboratory, University of Guam, Mangilao, Guam
Developing workable stabilizing techniques to mitigate the effects of coastal construction, ships
groundings and destructive fishing have been challenging well-informed decision makers for
the past 30 years. Coral communities reduced into rubble are less likely to provide potential
substrate for recruits due to instability and have slim chances to recover. We tested the efficacy
of using two species of corals with contrasting morphologies as rubble consolidators. Three
experimental plots were established in a 14 m2rubble field at 15 m depth in Sumay Mound,
Apra Harbor, Guam. Eighteen fragments each of Porites rus, a submassive species that forms
basal plates and Porites cylindrica, an upright branching species were transplanted to each plot
in June 2006. We cemented each fragment to pieces of rubble to provide minimum stability and
monitored for consolidating ability, measured in survival and basal growth and branching. We
hypothesized that P. rus, which is hardy and forms extensive basal plates like forming plate
would be superior as a consolidator to P. cylindrica. After 13 months, growth and overall
survival varied significantly between species. Survival of P. rus was 99% and 80% for P.
cylindrica. Monthly mean basal growth was 0.76 mm for P. rus and 0.16 mm for P. cylindrica.
Porites rus proved superior as a stabilizer due to its plate-like forming base that enhanced
fragment stability. P. cylindrica failed to attach to substrate and its mortality was higher.
Transplants required occasional recementing in the early stages and cleaning of seasonally
abundant macroalgae. Our study demonstrated that a morphologically complex, hardy, plateforming
coral species can be used to stabilize coral rubble. With minimum maintenance at posttransplantation,
Porites rus established themselves within one year and showed positive growth,
high survival and attachment to the substrate.
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