11th ICRS Abstract book - Nova Southeastern University
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11th ICRS Abstract book - Nova Southeastern University

11th ICRS Abstract book - Nova Southeastern University 11th ICRS Abstract book - Nova Southeastern University

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14-14 Environmentally-Mediated Variation in Larval Traits And Linkages To Juvenile Survival in Two Reef Fishes Su SPONAUGLE* 1 , Tauna RANKIN 1 , Kirsten GRORUD-COLVERT 2 1 Marine Biology & Fisheries, RSMAS/University of Miami, Miami, FL, 2 PISCO/COMPASS, Oregon State University, Corvallis, OR Population connectivity of benthic marine organisms depends on larval transit through the ocean as well as successful settlement and survival of young recruits. Thus environmental and oceanographic processes have the potential to play a significant role in population connectivity through their influence on early life history traits such as larval and juvenile growth, pelagic larval duration (PLD), and size and condition at settlement. We examined these otolith-based traits in multiple monthly cohorts of two common coral reef fishes, the bluehead wrasse Thalassoma bifasciatum and bicolor damselfish Stegastes partitus, in the Florida Keys to evaluate the role of water temperature and larval traits on early juvenile survival. Seasonal variation in water temperature explained a significant proportion of the variation in early life history traits among cohorts of both species, with potential consequences for the amount of time larvae have to disperse to suitable settlement habitats. Within cohorts, comparison of the distribution of early life history traits among late-stage larvae, and new and older recruits demonstrated that recruit survivorship is non-random and influenced by PLD, larval size and condition at settlement, and early juvenile growth. Contrasting patterns between species in the distribution of traits of young survivors suggest that the two species experience conflicting constraints as recruits. 14-15 Simulated Regional-Scale Genetic Structure of Caribbean and Southeast Asian Coral Reef Communities Johnathan KOOL* 1 , Claire PARIS 2 , Robert COWEN 1 1 Marine Biology and Fisheries, RSMAS - University of Miami, Miami, FL, 2 Applied Marine Physics, RSMAS - University of Miami, Miami, FL Recent advances in the development of coupled bio-oceanographic larval dispersal models have opened up new opportunities for evaluating large-scale population genetic structure in marine environments. Using this approach, it is possible to create transition matrices describing migration between different patch environments. Expected genetic structure (neutral or incorporating selection) may then be evaluated through projection using either classic matrix analysis or individual-based models. In this study, transition matrices based on larval dispersal patterns were generated and projected for two areas of interest: the Caribbean and the Coral Triangle Region of Southeast Asia (Philippines, Indonesia, Papua New Guinea). Preliminary results for the Caribbean indicate a strong east-west break (Gulf of Venezuela to Puerto Rico), which is consistent with previous field-based studies. Weaker clusters in other areas are also anticipated, as well as a cline through the Bahamas. Results for the Coral Triangle region are more complex due to current reversals, however the results suggest that if contemporary migration patterns are primarily responsible for creating genetic structure, then clusters in the Banda Sea region, in the vicinity of the Makassar Strait and the Celebes Sea, and along the eastern portion of Sulawesi should be evident. Although the results are specific to the set of life-history characteristics adopted in the simulations, they do appear to be robust, and provide a means of bridging the gap between observed marine population genetic patterns and biooceanographic processes. Oral Mini-Symposium 14: Reef Connectivity 14-16 Modeling The Influence Of Genotypic Diversity On Coral Meta-Population Structure Claire PARIS* 1 , Iliana BAUMS 2 1 Applied Marine Physics, Rosenstiel School of Marine and Atmospheric Science, miami, FL, 2 Department of Biology, The Pennsylvania State University, University Park, PA In sessile benthic invertebrates such as reef-building corals, fertilization is density dependent. Determining factors include the abundance, spatial distribution, and genetic makeup of those partners. Hence, the total number of larvae produced differs widely among populations in space and time. For instance, some hermaphroditic broadcast spawning corals reproduce mainly by asexual means (e.g. fragmentation) that can result in large monoclonal stands yet these species are self-incompatible. Such populations are unlikely to produce sexual offspring due to the lack of non-self mates. In turn, the genotypic (clonal) makeup of individual populations may influence the larger-scale meta-population structure. To test this hypothesis, we use estimates of clonal structure in several Acropora palmata populations in the Caribbean to scale the total larval output and simulate dispersal. Mortality rates and development times measured in the laboratory serve to parameterize the biophysical model. Sensitivity analyses of life history traits and scaled production on population connectivity networks are used to quantify the relative influence of the genetic makeup on the survivors in the meta-population. 14-17 Reef Fishes As "Living Tracers Of Connectivity" Patrick COLIN* 1 1 Coral Reef Research Foundation, Koror, Palau Comparisons of the distribution patterns of small reef fishes with limited larval dispersal to ocean current patterns, determined by satellite-tracked current drifters, provide an alternative method to biophysical modeling and genetic-based studies for assessing both connections and barriers within the tropical western North Atlantic (TWNA). The neon gobies (Elacatinus), the most speciose fish genus in the region, and other fish genera often have limited geographic distributions displaying similar distribution patterns among species. These patterns are the result of a natural connectivity experiment running since at least the last glacial low water and as such integrate the biological and physical aspects of connectivity over time. Oceanographic isolating mechanisms consistent with fish range limits have been identified and these modest zoogeographic barriers, combined with limits on fish larval dispersal, are responsible for the observed patterns of distribution. Consequently these fishes are indicators of connectivity and their zoogeography implies the TWNA is divisible into a series of enclave-like regions with limited genetic and ecological exchange among them. Even for reef fish species with longer maximum larval lives, the vast majority of larvae would recruit within their home enclaves and, as such, proposed enclaves provide an indication of ecological connectivity among nearly all reef fishes relevant to fisheries management and marine protected area design. 113

14-18 Meso-Scale Hydrodynamic Features And The Structure Of Great Barrier Reef Fish Communities Michael EMSLIE* 1 , Alistair CHEAL 1 , Angus THOMPSON 1 , Hugh SWEATMAN 1 , Severine CHOUKROUN 1 , Julian CALEY 1 1 Long Term Monitoring, Australian Institute of Marine Science, Townsville, Australia Coral reef communities are among the most diverse and threatened ecosystems on Earth leading to strident calls for urgent conservation measures, particularly the establishment of extensive networks of Marine Protected Areas. As well as protecting a range of species and habitats the reserves in a network should be linked by larval dispersal. The scale of connectivity in reef environments is uncertain. Recent findings suggest that selfrecruitment is much more common than originally thought, but the balance between selfrecruitment and long distance dispersal is unknown. Here we use long-term monitoring data from a significant section of Australia’s Great Barrier Reef that integrates the effects of ecological processes on communities comprising more than 200 species of fishes over more than a decade. This revealed previously undescribed, strong meso-scale structure of GBR reef fish communities that were associated with major hydrodynamic features. We postulate that these oceanographic features provide temporally stable barriers to ecologically significant fish dispersal among seven major community types within 1200 kilometres of reef matrix. We also propose that self-recruitment can apply not only to local scales but also has a regional context defined by oceanographic features. 14-19 Distribution, Abundance, And Genetics Of Corals Throughout The N. Gulf Of Mexico: The World’s Largest Coral Settlement Experiment Paul W. SAMMARCO* 1 , Amy D. ATCHISON 1 , Daniel A. BRAZEAU 2 , Gregory S. BOLAND 3 , Steven B. HARTLEY 4 , Angela LIRETTE 1 1 Louisiana Universities Marine Consortium (LUMCON), Chauvin, LA, 2 Pharmaceutical Genetics Laboratory, University of Buffalo, Buffalo, NY, 3 Minerals Management Service, US Department of the Interior, New Orleans, LA, 4 National Wetlands Research Center, US Geological Survey, Lafayette, LA Thousands of oil/gas platforms in the N. Gulf of Mexico (GOM) provide hard substratum where none existed prior to the Pleistocene. This has facilitated biogeographic extension of Caribbean reef fauna in the GOM. We quantified the distribution and abundance of scleractinian corals, hermatypic and ahermatypic, by surveying a total of 48 platforms around the Flower Garden Banks (FGB) and along four transects across the continental shelf: (T-I) Corpus Christi, TX, USA; (T-II) Lake Sabine, TX; (T-III) Terrebonne Bay, LA; and (T-IV) Mobile, AL. We also assessed genetic affinities between coral populations on the platforms and on the FGB to < 37 m using AFLPs. The western limit for hermatypes was near the shelf edge in T-IV. The highest densities of hermatypes were at the shelf edge, ~175-225 km offshore, in T-II&III. Some hermatypes were found in T-IV - their eastern limit. Ahermatypes (Tubastraea coccinea, Oculina diffusa, Phyllangia americana) were absent inshore and in the north-central region. A GIS analysis of coral data, salinity, temperature, dis-O2, phosphate, and nitrate concentrations indicated that lower salinities and temperatures are the major factors forcing community structure. Hermatypic species diversity peaked near the FGB. Genetic analyses performed on Madracis decactis revealed high self-recognition and site fidelity in M. decactis in T-III&IV, with little recognition across the mouth of the Mississippi River. In Tubastraea coccinea (invasive species), cross-recognition was higher between platforms within a transect, but absent across the river mouth. The Mississippi River is an effective biogeographic barrier to dispersal. These brooders are highly effective at colonizing patchy habitats at this scale – moreso than the broadcasters Diploria strigosa and Montastraea cavernosa - rare or absent over most of the Gulf, indicating less effective dispersal capabilities. Oral Mini-Symposium 14: Reef Connectivity 14-20 Genetic Connectivity Of Two Scleractinian Corals In Indonesia On Multiple Spatial Scales Craig STARGER* 1,2 , Paul BARBER 3 , Mark ERDMANN 4 , Andrew BAKER 5 1 Boston University Marine Program, Boston, MA, 2 Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, 3 Department of Biology, Boston University, Boston University Marine Program, Boston, MA, 4 Indonesia Marine Program, Conservation International, Denpasar, Bali, Indonesia, 5 Marine Biology and Fisheries, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL The Indonesian seas are home to some of the most biologically diverse marine ecosystems on Earth. They are also among the most threatened marine regions in the world. Studies focusing on genetic connectivity can shed light on the natural history of threatened populations while providing data that are useful to conservation managers. We have chosen the stony corals Pocillopora damicornis and Seriatopora hystrix to test hypotheses on barriers to larval dispersal. Microsatellite markers indicated that although coral populations are significantly differentiated across Indonesia, the level of genetic structure is much lower than that seen in other taxa. Gene flow and immigration estimates indicate that most populations are primarily self-seeding, however long distance dispersal is also occurring, maintaining connectivity across the entire Indonesian archipelago. A closer examination of connectivity on a regional scale was performed in the Bird’s Head Seascape of West Papua, where conservation managers are currently incorporating genetic data into the design of marine protected area networks. Similar to the country-wise assessment, there do not appear to any major barriers to dispersal within the Bird’s Head region. However, populations of both coral species are still primarily self-seeding, and the majority of genetic diversity is explained by within-population variation. A Bayesian assignment test and jackknifing approach were applied to examine the effect of population decline on overall connectivity in West Papua. Self-recruitment nearly always increased when populations were removed from the estimation of overall connectivity. This high sensitivity of the entire system to the decline of any individual population suggests that a network of marine protected areas covering a large geographic range is the best conservation strategy for maintaining connectivity in the Bird’s Head Seascape. In general, coral populations exhibit much lower genetic structure on a regional scale than other taxa. 14-21 Routine And Rare Genetic Connections in Corals Off Northwest Australia Jim UNDERWOOD* 1 , Luke SMITH 1 , Madeleine VAN OPPEN 2 , James GILMOUR 1 1 Australian Institute of Marine Science, Perth, Australia, 2 Australian Institute of Marine Science, Townsville, Australia The extent to which marine populations are connected by larval dispersal has profound influences on the ecology and evolution of species; from the short-term regulation and survival of communities to the long-term processes of adaptation to environmental change and speciation. Here, we use microsatellite DNA markers to quantify the genetic structure and infer the ecologically and evolutionarily relevant scales of dispersal of broadcast spawning coral (Acropora tenuis) and a brooding coral (Seriatopora hystrix) from isolated reefs off northwest Australia. For the brooder, whose larvae are competent to settle immediately after release, significant genetic subdivision over scales of tens of metres indicated that the majority of larvae recruit to within 100 m of their natal colony. However, occasional dispersal over tens of kilometres supplemented this localised recruitment, with putative source and sink dynamics associated with levels of disturbance and recovery from a recent and catastrophic coral bleaching. Additionally, prodigious genetic differences were detected among reef systems, indicating that dispersal over multiple generations of S. hystrix larvae over 100s of kilometres is rare. In contrast to the brooder, the broadcast spawned larvae of A. tenuis require about three days before competency is obtained, and as expected, levels of subdivision were an order of magnitude smaller compared with S. hystrix. However, significant differences were detected between sites separated by less than ten kilometres, providing evidence that these systems, reefs and some reef patches are predominantly self-seeding. However, genetic divergence between the coastal and offshore zones was greater than expected by the geographic separation of systems, indicating that connectivity between these zones via transport of A. tenuis larvae on oceanic currents occurs rarely. The primary management implication is that short-term recovery after severe disturbance requires the input of larvae from viable coral communities within kilometres to a few tens of kilometres away. 114

14-14<br />

Environmentally-Mediated Variation in Larval Traits And Linkages To Juvenile<br />

Survival in Two Reef Fishes<br />

Su SPONAUGLE* 1 , Tauna RANKIN 1 , Kirsten GRORUD-COLVERT 2<br />

1 Marine Biology & Fisheries, RSMAS/<strong>University</strong> of Miami, Miami, FL,<br />

2 PISCO/COMPASS, Oregon State <strong>University</strong>, Corvallis, OR<br />

Population connectivity of benthic marine organisms depends on larval transit through<br />

the ocean as well as successful settlement and survival of young recruits. Thus<br />

environmental and oceanographic processes have the potential to play a significant role in<br />

population connectivity through their influence on early life history traits such as larval<br />

and juvenile growth, pelagic larval duration (PLD), and size and condition at settlement.<br />

We examined these otolith-based traits in multiple monthly cohorts of two common coral<br />

reef fishes, the bluehead wrasse Thalassoma bifasciatum and bicolor damselfish<br />

Stegastes partitus, in the Florida Keys to evaluate the role of water temperature and larval<br />

traits on early juvenile survival. Seasonal variation in water temperature explained a<br />

significant proportion of the variation in early life history traits among cohorts of both<br />

species, with potential consequences for the amount of time larvae have to disperse to<br />

suitable settlement habitats. Within cohorts, comparison of the distribution of early life<br />

history traits among late-stage larvae, and new and older recruits demonstrated that<br />

recruit survivorship is non-random and influenced by PLD, larval size and condition at<br />

settlement, and early juvenile growth. Contrasting patterns between species in the<br />

distribution of traits of young survivors suggest that the two species experience<br />

conflicting constraints as recruits.<br />

14-15<br />

Simulated Regional-Scale Genetic Structure of Caribbean and Southeast Asian<br />

Coral Reef Communities<br />

Johnathan KOOL* 1 , Claire PARIS 2 , Robert COWEN 1<br />

1 Marine Biology and Fisheries, RSMAS - <strong>University</strong> of Miami, Miami, FL, 2 Applied<br />

Marine Physics, RSMAS - <strong>University</strong> of Miami, Miami, FL<br />

Recent advances in the development of coupled bio-oceanographic larval dispersal<br />

models have opened up new opportunities for evaluating large-scale population genetic<br />

structure in marine environments. Using this approach, it is possible to create transition<br />

matrices describing migration between different patch environments. Expected genetic<br />

structure (neutral or incorporating selection) may then be evaluated through projection<br />

using either classic matrix analysis or individual-based models. In this study, transition<br />

matrices based on larval dispersal patterns were generated and projected for two areas of<br />

interest: the Caribbean and the Coral Triangle Region of Southeast Asia (Philippines,<br />

Indonesia, Papua New Guinea). Preliminary results for the Caribbean indicate a strong<br />

east-west break (Gulf of Venezuela to Puerto Rico), which is consistent with previous<br />

field-based studies. Weaker clusters in other areas are also anticipated, as well as a cline<br />

through the Bahamas. Results for the Coral Triangle region are more complex due to<br />

current reversals, however the results suggest that if contemporary migration patterns are<br />

primarily responsible for creating genetic structure, then clusters in the Banda Sea region,<br />

in the vicinity of the Makassar Strait and the Celebes Sea, and along the eastern portion<br />

of Sulawesi should be evident. Although the results are specific to the set of life-history<br />

characteristics adopted in the simulations, they do appear to be robust, and provide a<br />

means of bridging the gap between observed marine population genetic patterns and biooceanographic<br />

processes.<br />

Oral Mini-Symposium 14: Reef Connectivity<br />

14-16<br />

Modeling The Influence Of Genotypic Diversity On Coral Meta-Population Structure<br />

Claire PARIS* 1 , Iliana BAUMS 2<br />

1 Applied Marine Physics, Rosenstiel School of Marine and Atmospheric Science, miami, FL,<br />

2 Department of Biology, The Pennsylvania State <strong>University</strong>, <strong>University</strong> Park, PA<br />

In sessile benthic invertebrates such as reef-building corals, fertilization is density dependent.<br />

Determining factors include the abundance, spatial distribution, and genetic makeup of those<br />

partners. Hence, the total number of larvae produced differs widely among populations in space<br />

and time. For instance, some hermaphroditic broadcast spawning corals reproduce mainly by<br />

asexual means (e.g. fragmentation) that can result in large monoclonal stands yet these species<br />

are self-incompatible. Such populations are unlikely to produce sexual offspring due to the lack<br />

of non-self mates. In turn, the genotypic (clonal) makeup of individual populations may<br />

influence the larger-scale meta-population structure. To test this hypothesis, we use estimates of<br />

clonal structure in several Acropora palmata populations in the Caribbean to scale the total<br />

larval output and simulate dispersal. Mortality rates and development times measured in the<br />

laboratory serve to parameterize the biophysical model. Sensitivity analyses of life history traits<br />

and scaled production on population connectivity networks are used to quantify the relative<br />

influence of the genetic makeup on the survivors in the meta-population.<br />

14-17<br />

Reef Fishes As "Living Tracers Of Connectivity"<br />

Patrick COLIN* 1<br />

1 Coral Reef Research Foundation, Koror, Palau<br />

Comparisons of the distribution patterns of small reef fishes with limited larval dispersal to<br />

ocean current patterns, determined by satellite-tracked current drifters, provide an alternative<br />

method to biophysical modeling and genetic-based studies for assessing both connections and<br />

barriers within the tropical western North Atlantic (TWNA). The neon gobies (Elacatinus), the<br />

most speciose fish genus in the region, and other fish genera often have limited geographic<br />

distributions displaying similar distribution patterns among species. These patterns are the<br />

result of a natural connectivity experiment running since at least the last glacial low water and<br />

as such integrate the biological and physical aspects of connectivity over time. Oceanographic<br />

isolating mechanisms consistent with fish range limits have been identified and these modest<br />

zoogeographic barriers, combined with limits on fish larval dispersal, are responsible for the<br />

observed patterns of distribution. Consequently these fishes are indicators of connectivity and<br />

their zoogeography implies the TWNA is divisible into a series of enclave-like regions with<br />

limited genetic and ecological exchange among them. Even for reef fish species with longer<br />

maximum larval lives, the vast majority of larvae would recruit within their home enclaves and,<br />

as such, proposed enclaves provide an indication of ecological connectivity among nearly all<br />

reef fishes relevant to fisheries management and marine protected area design.<br />

113

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