11th ICRS Abstract book - Nova Southeastern University

14.441
Population Genetics Of Spotted Seahorses (hippocampus Kuda) in Thai Waters
Thadsin PANITHANARAK* 1 , Ratima KARUWANCHAROEN 1 , Uthairat NA-
NAKORN 2 , Thuy NGUYEN 3
1 Institute of Marine Science, Burapha University, Chonburi, Thailand, 2 Department of
Aquaculture, Faculty of Fisheries, Kasetsart University, Bangkok, Thailand, 3 Network of
Aquaculture Centers in Asia-Pacific, Bangkok, Thailand
Population genetics of spotted seahorse (Hippocampus kuda) was studied in order to
investigate genetic diversity, level of genetic differentiation and evolution of the species
in Thai waters derived from the analysis of mtDNA control region. The study was also
carried out to identify the populations of Thai waters for effective conservation and
management of this vulnerable coral reef species. The spotted seahorses were collected
from four populations of Eastern and Western Coast of the Gulf of Thailand and one
population of the Andaman Sea (101 individuals collected). Of all mtDNA sequences
analyzed (353 bp), seven haplotypes were found. Five haplotypes were observed and
shared between Eastern and Western Coast of the Gulf of Thailand while the others were
found only in the Andaman Sea with 13-17 nucleotide differences compared to the
formers. Genetic differentiation was observed in pairs of their populations (FST P-value
< 0.0001) in consistent with high percentage of genetic variance observed between two
groups of the populations (95.56%) using the analysis of molecular variance (AMOVA).
Neighbour-joining trees showing relationship among seahorses from Thai waters and
other regions suggested that populations of the Gulf of Thailand and the Andaman Sea
were phylogenetically different and placed in separated evolutionary groups. The
populations of the Gulf of Thailand had a close relationship with populations of the
Pacific Ocean (Philippines, Taiwan and Fiji, 84% bootstrap support). In contrast, the
population of the Andaman Sea was grouped with populations from the Indian Ocean and
closely related with populations of Indonesia. All results indicated that populations from
the Gulf of Thailand and the Andaman Sea should be treated as separate conservation
units. However, more specimens would be needed to confirm the differentiation between
the populations, especially, the specimens from the Andaman Sea.
14.442
Population Genetic Study Of acropora Digitifera Using Microsatellite Markers in
Sekisei Reef
Yuichi NAKAJIMA* 1 , Akira NISHIKAWA 2 , Kazuhiko SAKAI 1
1 2
University of the Ryukyus, Motobu-cho, Japan, James Cook University, Townsville,
Australia
For understanding maintenance and recovery mechanism of coral populations, it is
essential to elucidate the genetic connectivity among the local populations. In Sekisei
Reef that is the largest coral reef in Japan, K. Nadaoka (in a report by Ministry of
Environment of Japan) estimated dispersal range of coral larvae from several local
populations by a computer simulation of seawater flow, and suggested that larval
dispersal of broadcast spawning corals may be limited among local populations in Sekisei
Reef. We examined the possibility suggested by K. Nadaoka by estimating gene flow of
Acropora digitifera among local populations in Sekisei Reef.
We selected six sites in Sekisei Reef, and collected small flagments of A. digitifera at
each site. Distances between sites were ranged from 6 to 25km. We used six
microsatellite markers for analyzing genetic difference among colonies. Our results
indicated that genetic differentiation of A. digitifera populations was very small in
Sekisei Reef. FST values among sites were ranged from 0.05 to 0.012. These values are
much lower than those reported for Seriatopora hystrix in Western Australia using
microsatellite markers; FST values were ranged from 0.045 to 0.187 in 3 to 23km spatial
scales in S. hystrix. This difference may be due to difference in mode of reproduction
between the two species; A. digitifera is a broadcast spawning coral and S. hystrix is a
planula brooding coral. If disturbance of coral communities occur patchily in several km
spatial scale, recovery of broadcast spawning coral populations such as A. digitifera at
disturbed reefs will be faster than that of brooding coral populations such as S. hystrix.
Poster Mini-Symposium 14: Reef Connectivity
14.443
Coral Recruits To Settlement Plates At Remote Locations Throughout The U.s. Pacific
Jean KENYON* 1
1 Coral Reef Ecosystem Division, NOAA Pacific Islands Fisheries Science Center, Honolulu, HI
The world-wide decline of coral reefs necessitates improved understanding of their intrinsic
capabilities for replenishment. The capacity of scleractinian corals to maintain or renew
genetically diverse populations through sexual reproduction is a key attribute of reef resilience.
Documenting the density, taxon, and size of coral recruits to settlement plates during known
time intervals is a widely used method of quantifying coral recruitment. Four deployments of
arrays of terra cotta settlement plates were made at six locations in the Northwestern Hawaiian
Islands at annual or biennial intervals between 2001 and 2006. Similar arrays were deployed at
four additional locations in the U.S. Pacific (Baker, Rose Atoll, Palmyra, Kingman) for two
consecutive, two-year periods, and a single deployment of two years’ duration was made at
Jarvis and at Swains, American Samoa. Most locations with multiple deployments showed
substantial temporal variability in the density of coral recruits. In the Northwestern Hawaiian
Islands, lowest average recruitment rates (9.0-11.3 recruits/m2/yr) were found at Midway and
Pearl and Hermes Atoll, respectively, and highest average rates were found at Maro (332.2
recruits/m2/yr). The taxonomic composition of the recruits (96.2% Pocilloporidae, 2.7%
Acroporidae, 1.1% Poritidae) did not reflect the composition of mature coral communities,
where the genus Porites dominates in all locations. No recruits were found at Rose Atoll or at
Swains, though arrays were emplaced in coral-rich habitats. Annual rates at the other four nearequatorial
locations ranged from 3.3 to 4.7 recruits/m2/yr. The taxonomic composition of the
recruits similarly was disharmonic with the composition of the mature coral communities at
these locations. The largest recruits were found at Baker (Pocillopora, 5.5 cm) and Kingman
(Acropora, 5.2 cm), but most recruits measured less than 2.5 mm. These results reveal the need
for further study of coral reproductive and recruitment processes in these remote areas, where
little data exist.
14.444
Variation in Spatial And Temporal Coral Recruitment Patterns On Fijian Reefs
Norman QUINN* 1 , Barbara KOJIS 2
1 St Croix East End Marine Park, Frederiksted, Virgin Islands (U.S.), 2 University of the Virgin
Islands, St Thomas, Virgin Islands (U.S.)
Community structure and recruitment patterns of scleractinian and milleporan corals were
investigated at Suva Harbour, Great Astrolabe Reef, and Taveuni in Fiji. Seventy five coral
species were recorded surveys with percentage coral cover ranging from 8% in polluted Suva
Harbour to 26% at Great Astrolabe Reef. Acroporids were the most dominant genus. The
density of coral recruits ranged from a mean of 20 to 1845 recruits m2. The lowest recruitment
rate occurred at Suva Harbour while the highest recruitment occurred on a reef periodically
disturbed by high rates of sedimentation. Larval settlement was >7 times greater in the
“summer” than the “winter”. The recruitment rate was greater than rate in the Mariana Islands
in the western Pacific, but lower than the highest settlement rates observed on the Great Barrier
Reef. The highest recorded recruitment rate in the Caribbean Sea is less than 1/3 of the
settlement observed in the best site in Fiji. The greatest variation in recruitment rates between
sites occurred within the Acroporidae. Recruits of the Pocilloporidae, Poritidae, Faviidae and
other species preferred settling in deeper water while Acroporidae preferred settling in shallow
waters. The high acroporid recruitment rate was probably related to the high frequency of
occurrence of the family. The high levels of recruitment of Acropora planulae in Fiji contrasts
with the paucity of Acropora recruitment in the Caribbean. This high recruitment rate of an
important shallow water coral family results in a greater resilience to natural disasters.
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