11th ICRS Abstract book - Nova Southeastern University

14-29
Complex Patterns of Genetic Connectivity in a Brooding Coral on the Great Barrier
Reef, Australia
Madeleine VAN OPPEN* 1 , Adrian LUTZ 1 , Glenn DE'ATH 2
1 Australian Institute of Marine Science, Townsville, MC, Australia, 2 Australian Institute
of Marine Science, Townsvile, MC, Australia
An understanding of the extent of larval transport in and out of reefs, as well as the
direction of larval dispersal will improve our ability to forecast whether and how fast reef
organisms are likely to recover from disturbance events that cause massive mortality.
Assessment of connectivity on the Great Barrier Reef (GBR) is complex, as the GBR is
extremely large (~350,000 km2, of which ~21,000 km2 consists of coral reef) and
comprises ~2,900 separate reefs. We assessed genetic connectivity among and diversity
within GBR populations of the brooding coral, Seriatopora hystrix. Approximately 1,800
specimens were collected across ~8.5 degrees of latitude and genotyped at ten
microsatellite loci. Although extensive mixing was obvious in some areas, for example
along the outer-shelf Ribbon reefs in the northern section of the GBR, high levels of
genetic subdivision were generally observed among populations. Nearby populations
from the same reef were in some cases as genetically distinct as populations hundreds of
kilometres away. A strong signature of recent admixture (i.e., linkage disequilibrium,
heterozygote deficits and high allelic diversity) was present in a subset of the populations,
and where both lagoonal and exposed sites were sampled on the same reef, the latter were
much more admixed. A hydrodynamic model is available for the northern section of the
GBR and a comparison of hydrodynamic and genetic data will be presented.
14-30
Population Genetics, Larval Dispersal, and Demographic Connectivity in Marine
Systems
Kimberley WEERSING* 1 , Robert TOONEN 2
1 Oceanography, University of Hawaii at Manoa, Honolulu, HI, 2 Hawaii Institute of
Marine Biology, University of Hawaii at Manoa, Kane`ohe, HI
We survey 300 published studies to synthesize life-history and population genetic
structure data from a broad array of benthic marine taxa (including ten coral species and
62 reef-associated species) to determine how well pelagic larval duration (PLD)
correlates with population genetic estimates of dispersal. Expanding on earlier studies,
we also explore other potential biophysical correlates of population substructure (genetic
marker class, habitat type, and larval swimming ability) that have not been considered in
previous meta-analyses. In contrast to previous studies concluding that planktonic
periods correlate well with inferred dispersal ability, we find that average PLD was
poorly correlated with population connectivity (FST). Furthermore, even this weak
correlation appears to be anchored by the zero PLD class, because removal of species that
lack a pelagic phase from the analysis resulted in a non-significant relationship between
F ST and mean PLD. A 3-way ANCOVA instead reveals that genetic marker class
(mtDNA, allozymes, and microsatellites) is responsible for most of the variation in FST (F
= 7.113, df = 2, p = 0.001), while neither habitat nor swimming ability were significant
factors. In contrast to the general expectation that microsatellite-based studies provide
the finest resolution of population structure, we find that significantly higher values of
FST are obtained with mtDNA than with either microsatellites or allozymes (which were
not significantly different). Useful predictors of the pattern and scale of dispersal play a
central role in both ecological and evolutionary studies, but as yet remain elusive; this
study suggests that mean PLD is at best a weak predictor of population genetic structure
and that estimates of larval dispersal will need to encompass both behavioral and physical
transport processes.
Oral Mini-Symposium 14: Reef Connectivity
14-31
Local And Regional Self-Recruitment in The Bicolor Damselfish (Stegastes Partitus) On
Turneffe Atoll in The Mesoamerican Barrier Reef
Eva SALAS* 1 , Helena MOLINA 1 , Dan HEATH 2
1 Centro de Investigación en Ciencias del Mar y Limnología (CIMAR), Universidad de Costa
Rica, San Jose, Costa Rica, 2 Great Lakes Institute for Environmental Research (GLIER),
University of Windsor, Windsor, ON, Canada
The scale of larval retention is of critical importance to define units of conservation for reef
fishes. By using genotype assignment techniques, we estimated the proportion of self
recruitment of Stegastes partitus, a Caribbean damselfish with a long (30-day) pelagic larval
phase. Adults and recently settled juveniles were collected from reefs located on Turneffe atoll
and the Belize barrier reef, and were genotyped at 12 microsatellite loci. We found that selfrecruitment
rates are relatively low at a local,