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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14-37 Genetic Connectivity in Philippine Waters: Insights On Patterns, Scales, And Processes Based On Various Marine Taxa Rachel RAVAGO GOTANCO* 1 , Marie Antonette JUINIO-MENEZ 1 1 Marine Science Institute, University of the Philippines, Quezon City, Philippines An understanding of connectivity among reef environments is of critical importance to the design and implementation of management and conservation schemes. Predicting patterns of reef connectivity remains a challenge, as connectivity is the result of a complex interaction of biological and physical factors and processes operating across a wide range of spatial and temporal scales. Genetic patterns of a variety of reef-associated species with varying dispersal potential, from different marine biogeographic regions in the Philippines provide insights on ecological and historical processes that structure marine populations in these regions. Genetic patchiness at scales finer than expected from potential dispersal based on life history traits coupled with local hydrographic features indicate key factors affecting benthic recruitment success determine genetic patterns. For species such as Tridacna crocea, Linckia laevigata, and Siganus fuscescens, these include the influence of distribution and extent of suitable habitats and degree of environmental disturbance. Within biogeographic regions, genetic patterns coupled with community structure and hydographic regimes provide useful insights relevant for fishery management considerations. Patterns of genetic variability among northwest Luzon populations of S. fuscescens and Tripneustes gratilla provide insight into the spatial scales and putative boundaries for connectivity and gene flow. Genetic patterns across regions, as in the case of T. crocea, S. fuscescens and Siganus argenteus populations across the eastern Philippine seaboard, and South China Sea and Sulu Sea populations of T. crocea and L. laevigata, indicate the influence of broadscale hydrographic features on population genetic structure. In the case of the spiny lobster Panulirus longipes, genetic connectivity coupled with subspecies distribution patterns provides insight into long-term evolutionary scale processes shaping genetic structure and species biogeography. 14-38 Long-Distance Gene Flow And Fine-Scale Genetic Differentiation in The Indo- Pacific Reef Fish, zebrasoma Flavescens Jeff EBLE* 1 , Rob TOONEN 1 , Larry BASCH 2 , Brian BOWEN 1 1 Hawaii Institute of Marine Biology, Kaneohe, HI, 2 University of Hawaii Pacific Cooperative Studies Unit, Honolulu, HI The remoteness of the Hawaiian Archipelago has proven to be a formidable barrier to the dispersal of marine species, resulting in high levels of endemism and corresponding genetic divergence. However, across the 2500 km of Hawaii’s islands and atolls, marine populations have historically been assumed to be panmictic. To compare patterns of connectivity within the archipelago to broader trans-Pacific patterns, we surveyed both mtDNA and nuclear markers in the Indo-Pacific reef fish, Zebrasoma flavescens. Adults were collected at multiple spatial scales (N = 824) from 21 sites including: (a) four West Pacific locations, (b) six sites within the newly created Northwestern Hawaiian Islands (NWHI) Marine National Monument, and (c) 10 sites within the Main Hawaiian Islands, four being located around the largest island in the archipelago, the island of Hawaii. Additional tests for sweepstakes recruitment were conducted on 212 newly recruited fish collected from seven Hawaii Island sites. Analysis of cytochrome b sequences demonstrated modest population structure across the West Pacific (Φst = 0.04; P = 0.034) and stronger genetic differentiation between the West Pacific and Hawaii (Φst = 0.09; P = 0.004). Analysis of 14 microsatellite loci indicate restricted gene flow between the newly established NWHI reserve and the main Hawaiian Islands (Fst = 0.008, P = 0.024), and genetic subdivision at scales of less than 50 km around Hawaii Island (Fst = 0.019, P < 0.001). Oral Mini-Symposium 14: Reef Connectivity 14-39 Population Structure And Genetic Connectivity Of Corals in Subtropical Eastern Australia Annika NOREEN* 1 , Peter HARRISON 1 , Madeleine VAN OPPEN 2 1 Department of Environmental Science and Management, Southern Cross University, Lismore, Australia, 2 Australian Institute of Marine Science, Townsville, Australia This study examines the population differentiation, genetic diversity, and connectivity of corals in the eastern Australian subtropics and the Great Barrier Reef. Several eastern Australian subtropical reefs have high coral cover (up to 85%) and relatively high species richness (90-140 species). High-latitude reefs might be increasingly vulnerable because of ocean acidification, lower genetic diversity and lower connectivity among reefs. We address some of the issues underlying these ecological questions using population-level genetics of five coral species. Over 1,200 samples have been taken from Seriatopora hystrix, Pocillopora damicornis, Acropora solitaryensis, Goniastrea favulus and Platygyra daedalea from subtropical reefs (Lord Howe Island, Middleton and Elizabeth reefs, the Solitary Islands and Flinders Reef) and several Great Barrier Reef locations. Nuclear DNA was extracted from each sample, and between 5 and 10 fluorescently-labelled microsatellite markers were amplified for each species using PCR. The alleles were then genotyped and scored. Seriatopora hystrix, a brooding coral, has highly differentiated populations between most of the locations. However, some populations sampled are undifferentiated despite considerable environmental variability, e.g. Lord Howe Island east coast versus western lagoon. Additionally, the Elizabeth reef lagoon population clusters with the Middleton reef lagoon population, despite being 50 km apart, as do their respective outer channel populations. The S. hystrix population at Flinders reef, southern Queensland, is most similar to that of Lord Howe Island, over 600 km further south. The three Great Barrier Reef locations are admixtures of several genetic populations and, as a group, highly differentiated from subtropical reefs. There is discernable gene flow between some populations, notably Middleton and Elizabeth reefs’ outer channel to Lord Howe Island. 14-40 The Missing Link To Population Genetic Structure in Brooding Corals: How Far Do Sperm Swim? Patricia WARNER* 1,2 , Bette WILLIS 1 , Madeleine VAN OPPEN 2 1 School of Marine and Tropical Biology and ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia, 2 Australian Institute of Marine Science, Townsville, Australia The processes that govern the population genetic structure of brooding corals may be different to those that govern broadcast spawning species because of differences in the frequency and scale of dispersal characteristic of internal versus external fertilization. Given that small and isolated populations may be at greater risk of decline and extinction compared to large and panmictic populations, investigating genetically effective population sizes of brooding species is important. Effective population sizes in hermaphroditic reef corals are expected to be several magnitudes smaller than the census size, due to inter-annual variation in census population sizes and fecundity, as well as possible influences of both asexual reproduction and self-fertilization. Analysis of highly polymorphic DNA markers of the brooding coral, Seriatopora hystrix, on the Great Barrier Reef (GBR) shows that allelic diversity is high across the GBR, but much smaller in each population, suggestive of small effective population sizes. Heterozygote deficits, indicative of non-random mating, are common in this species, which is consistent with rapid settlement of the larvae shortly after release. Knowledge of fine-scale connectivity patterns within populations of brooding corals may help to elucidate the broad-scale patterns in genetic structure. Limited sperm dispersal may amplify signals of geographic subdivision, but current knowledge of the frequency and scale of dispersal of spermatozoa in brooding species is limited, and is absent for S. hystrix. To determine the spatial extent of spermatozoa dispersal, the genotypes of all colonies within a mapped study population in the Palm Islands, central GBR, were compared with those of the brooded larvae of adults sampled from the center of the mapped population. Furthermore, we assessed the timing of spermatozoa and larval release with histological monitoring of adult gametogenic tissue throughout the reproductive season. 119

14-41 Fine-scale Spatial Genetic Structure in the Caribbean Staghorn Coral Acropora cervicornis Silvia LIBRO* 1 , Steve VOLLMER 1 1 Marine Science Center, Northeastern University, Nahant, MA Localized spatial genetic structure (SGS), i.e. the non-random association of genetic relatedness among individuals in space, can be caused by a variety of demographic and evolutionary processes including limited dispersal, inbreeding, and selection. SGS has been studied extensively in plants, in order to estimate fine-scale patterns of dispersal, but has rarely been examined in sessile marine taxa. Here we investigated the possibility that SGS might be important in the staghorn coral Acropora cervicornis. Staghorn corals from four populations were mapped along permanent transects and genotyped with five microsatellite loci. Our results show that A. cervicornis exhibits localized SGS within reefs (out to 14 meters) due to both the spatial aggregation of clones and the non-random association of genets on reefs. We show that patches of A. cervicornis can be highly inter-related as well with relatedness on the order of cousins. We also detected moderate to high levels of population genetic structure among reefs over spatial scales as small as 2kms, but no evidence of isolation by distance among reefs. We suggest that the localized SGS, high relatedness among genets within reefs, and strong population structure between reefs is the results of rare cohort recruitment. 14-42 Understanding Patterns Of Gene Flow in Coral Reef Fishes: Multiple Species And Multiple Scales. Joshua DREW* 1 , Paul BARBER 2 1 Marine Program, Boston University, Woods Hole, MA, 2 Marine Program, Boston University, Boston, MA Understanding the spatial scales over which populations of coral reef fishes are connected is important for elucidating evolutionary patterns as well as in setting conservation priorities. In this presentation we compare patterns of genetic connectivity of several common coral reef fishes over multiple spatial scales. On the finest scale, between the islands of Fiji we see broad scale genetic homogenization with most, but not all of the species we examine. However, on the next highest spatial scale (between Fiji and the rest of Melanesia) we see evidence for regional endemism within five species of fishes. Expanding further, we investigate two species of fish Amphiprion melanopus and Pomacentrus moluccenis [Pomacentridae] whose species ranges are entirely within Melanesia and Indonesia. Here we see evidence for restricted gene flow across the Indo- West Pacific archipelagos ultimately leading to the evolution of peripheral populations into reproductively isolated monophyletic clades. Finally at the largest spatial scales we use the widely distributed species Halichoeres hortulanus [Labridae], to investigate gene flow across the Indian and Pacific oceans, and discover significant barriers to gene flow between these oceans occurring in the Indonesian archipelago. Our results demonstrate that despite having pelagic larvae and the ability to distribute genes over broad geographic differences, some coral reef fish populations are geographically structured, but the magnitude of that structure depends on the spatial scale considered. Oral Mini-Symposium 14: Reef Connectivity 14-43 Connectivity in A Caribbean Octocoral: A Tale Of Three Datasets Howard LASKER* 1 , Jaret BILEWITCH 1 , Stefano GOFFREDO 2 1 Program in Evolution, Ecology and Behavior, and Dept of Geology, University at Buffalo, Buffalo, NY, 2 Department of Evolutionary and Experimental Biology, University of Bologna, Bologna, Italy Characterizations of connectivity vary with the spatial and temporal scales inherent in the techniques used to assess connectivity. The Caribbean octocoral, Pseudopterogorgia elisabethae has been harvested on the Little Bahama Bank for over 10 years. The harvest, which involves cropping colonies, leaves areas with reduced numbers of reproductive colonies. This reduction in reproductive colonies should reduce local recruitment, since P. elisabethae surface broods and has negatively buoyant planulae. We examined connectivity among populations on the Little Bahama Bank and throughout the northern Bahamas on differing spatial and temporal scales by comparing recruitment before and after harvesting, comparing the population size/age structure between harvested and unharvested areas and examining population genetic structure. Recruitment at sites in 2004 and 2005 varied with local population density, but changes in recruitment due to harvesting were no greater than inter-annual variation in recruitment at all sites. However, the size structure of populations that were subjected to up to 3 episodes of harvesting had depressed proportions of small colonies suggesting that local recruitment and the extended depression of local recruitment affected population demographics. Microsatellite analyses of populations on the Little Bahama Bank detected minimal population clustering but did identify significant FST values. We found high levels of structure on larger scales. The data suggest that in any single year recruits readily move over scales >10 -1 km. However, over the scale of a decade and summed across harvesting encompassing several kilometers a substantial portion of recruitment is local. Over scales of decades and 10 to >100 km there is sufficient migration to reduce but not eliminate population genetic structure. There is limited migration across oceanographic barriers. 14-44 Preliminary Analysis of Acropora palmata Gene Flow in Reefs of the US Virgin Islands William SCHILL* 1 , Caroline ROGERS 2 , Erinn MULLER 3 , Anthony SPITZACK 4 , Iliana BAUMS 5 1 Natl. Fish Health Research Laboratory, USGS-Leetown Science Center, Kearneysville, WV, 2 Virgin Islands National Park, USGS-Florida Integrated Science Center, St. John, Virgin Islands (U.S.), 3 Florida Institute of Technology, Melbourne, FL, 4 USGS-Florida Integrated Science Center, St. John, Virgin Islands (U.S.), 5 The Pensylvania State University, University Park, PA Two regionally isolated populations of Acropora palmata that were previously identified are generally demarcated by Mona Island, east of Puerto Rico. To further examine pathways of gene flow in the eastern zone, we determined the genotype at five polymorphic microsatellite loci of 256 colonies of Acropora palmata from six sites on St. John, and 92 additional colonies from two sites at Buck Island/St. Croix, USVI. Data analysis using AMOVA demonstrated that 98% of the genetic variation was within collections, while 2% was among the island groupings. Sixty-five of the 348 colonies were clonal. The incidence of clonality may be influenced by differential spatial scales of sampling at various sites, but was lowest in samples from the South Fore Reef of Buck Island (0 of 50 colonies), and highest at the Hawksnest Bay, St. John site (21 of 42 colonies). When clonemates were removed from the analysis, the differentiation of the island groupings disappeared and the algorithm used by the program, structure v. 2.2, failed to identify more than a single cluster. Pairwise population FST and RST values, however, indicated significant differentiation for combinations of the Yawzi Point or Saltpond Bay, St. John, collections with the two St. Croix collections. We also examined distributions of sample pairs’ relatedness. Within collections, mean relatedness was significantly higher between sample pairs from the two St. Croix collections than between sample pairs of other collections. Thus, the St. Croix collections seem to exhibit some cohesiveness not generally found in the St. John collections. The Saltpond Bay collection, however, was distinct from the other five St. John collections in that 5.5% of the possible pairings shared at least one allele at each of the five loci. Analyses of individuals with similar genotypes suggest potential connections between reefs. 120

14-37<br />

Genetic Connectivity in Philippine Waters: Insights On Patterns, Scales, And<br />

Processes Based On Various Marine Taxa<br />

Rachel RAVAGO GOTANCO* 1 , Marie Antonette JUINIO-MENEZ 1<br />

1 Marine Science Institute, <strong>University</strong> of the Philippines, Quezon City, Philippines<br />

An understanding of connectivity among reef environments is of critical importance to<br />

the design and implementation of management and conservation schemes. Predicting<br />

patterns of reef connectivity remains a challenge, as connectivity is the result of a<br />

complex interaction of biological and physical factors and processes operating across a<br />

wide range of spatial and temporal scales. Genetic patterns of a variety of reef-associated<br />

species with varying dispersal potential, from different marine biogeographic regions in<br />

the Philippines provide insights on ecological and historical processes that structure<br />

marine populations in these regions. Genetic patchiness at scales finer than expected from<br />

potential dispersal based on life history traits coupled with local hydrographic features<br />

indicate key factors affecting benthic recruitment success determine genetic patterns. For<br />

species such as Tridacna crocea, Linckia laevigata, and Siganus fuscescens, these include<br />

the influence of distribution and extent of suitable habitats and degree of environmental<br />

disturbance. Within biogeographic regions, genetic patterns coupled with community<br />

structure and hydographic regimes provide useful insights relevant for fishery<br />

management considerations. Patterns of genetic variability among northwest Luzon<br />

populations of S. fuscescens and Tripneustes gratilla provide insight into the spatial<br />

scales and putative boundaries for connectivity and gene flow. Genetic patterns across<br />

regions, as in the case of T. crocea, S. fuscescens and Siganus argenteus populations<br />

across the eastern Philippine seaboard, and South China Sea and Sulu Sea populations of<br />

T. crocea and L. laevigata, indicate the influence of broadscale hydrographic features on<br />

population genetic structure. In the case of the spiny lobster Panulirus longipes, genetic<br />

connectivity coupled with subspecies distribution patterns provides insight into long-term<br />

evolutionary scale processes shaping genetic structure and species biogeography.<br />

14-38<br />

Long-Distance Gene Flow And Fine-Scale Genetic Differentiation in The Indo-<br />

Pacific Reef Fish, zebrasoma Flavescens<br />

Jeff EBLE* 1 , Rob TOONEN 1 , Larry BASCH 2 , Brian BOWEN 1<br />

1 Hawaii Institute of Marine Biology, Kaneohe, HI, 2 <strong>University</strong> of Hawaii Pacific<br />

Cooperative Studies Unit, Honolulu, HI<br />

The remoteness of the Hawaiian Archipelago has proven to be a formidable barrier to the<br />

dispersal of marine species, resulting in high levels of endemism and corresponding<br />

genetic divergence. However, across the 2500 km of Hawaii’s islands and atolls, marine<br />

populations have historically been assumed to be panmictic. To compare patterns of<br />

connectivity within the archipelago to broader trans-Pacific patterns, we surveyed both<br />

mtDNA and nuclear markers in the Indo-Pacific reef fish, Zebrasoma flavescens. Adults<br />

were collected at multiple spatial scales (N = 824) from 21 sites including: (a) four West<br />

Pacific locations, (b) six sites within the newly created Northwestern Hawaiian Islands<br />

(NWHI) Marine National Monument, and (c) 10 sites within the Main Hawaiian Islands,<br />

four being located around the largest island in the archipelago, the island of Hawaii.<br />

Additional tests for sweepstakes recruitment were conducted on 212 newly recruited fish<br />

collected from seven Hawaii Island sites. Analysis of cytochrome b sequences<br />

demonstrated modest population structure across the West Pacific (Φst = 0.04; P = 0.034)<br />

and stronger genetic differentiation between the West Pacific and Hawaii (Φst = 0.09; P =<br />

0.004). Analysis of 14 microsatellite loci indicate restricted gene flow between the newly<br />

established NWHI reserve and the main Hawaiian Islands (Fst = 0.008, P = 0.024), and<br />

genetic subdivision at scales of less than 50 km around Hawaii Island (Fst = 0.019, P <<br />

0.001).<br />

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

14-39<br />

Population Structure And Genetic Connectivity Of Corals in Subtropical Eastern<br />

Australia<br />

Annika NOREEN* 1 , Peter HARRISON 1 , Madeleine VAN OPPEN 2<br />

1 Department of Environmental Science and Management, Southern Cross <strong>University</strong>, Lismore,<br />

Australia, 2 Australian Institute of Marine Science, Townsville, Australia<br />

This study examines the population differentiation, genetic diversity, and connectivity of corals<br />

in the eastern Australian subtropics and the Great Barrier Reef. Several eastern Australian<br />

subtropical reefs have high coral cover (up to 85%) and relatively high species richness (90-140<br />

species). High-latitude reefs might be increasingly vulnerable because of ocean acidification,<br />

lower genetic diversity and lower connectivity among reefs. We address some of the issues<br />

underlying these ecological questions using population-level genetics of five coral species.<br />

Over 1,200 samples have been taken from Seriatopora hystrix, Pocillopora damicornis,<br />

Acropora solitaryensis, Goniastrea favulus and Platygyra daedalea from subtropical reefs<br />

(Lord Howe Island, Middleton and Elizabeth reefs, the Solitary Islands and Flinders Reef) and<br />

several Great Barrier Reef locations. Nuclear DNA was extracted from each sample, and<br />

between 5 and 10 fluorescently-labelled microsatellite markers were amplified for each species<br />

using PCR. The alleles were then genotyped and scored. Seriatopora hystrix, a brooding coral,<br />

has highly differentiated populations between most of the locations. However, some<br />

populations sampled are undifferentiated despite considerable environmental variability, e.g.<br />

Lord Howe Island east coast versus western lagoon. Additionally, the Elizabeth reef lagoon<br />

population clusters with the Middleton reef lagoon population, despite being 50 km apart, as do<br />

their respective outer channel populations. The S. hystrix population at Flinders reef, southern<br />

Queensland, is most similar to that of Lord Howe Island, over 600 km further south. The three<br />

Great Barrier Reef locations are admixtures of several genetic populations and, as a group,<br />

highly differentiated from subtropical reefs. There is discernable gene flow between some<br />

populations, notably Middleton and Elizabeth reefs’ outer channel to Lord Howe Island.<br />

14-40<br />

The Missing Link To Population Genetic Structure in Brooding Corals: How Far Do<br />

Sperm Swim?<br />

Patricia WARNER* 1,2 , Bette WILLIS 1 , Madeleine VAN OPPEN 2<br />

1 School of Marine and Tropical Biology and ARC Centre of Excellence for Coral Reef Studies,<br />

James Cook <strong>University</strong>, Townsville, Australia, 2 Australian Institute of Marine Science,<br />

Townsville, Australia<br />

The processes that govern the population genetic structure of brooding corals may be different<br />

to those that govern broadcast spawning species because of differences in the frequency and<br />

scale of dispersal characteristic of internal versus external fertilization. Given that small and<br />

isolated populations may be at greater risk of decline and extinction compared to large and<br />

panmictic populations, investigating genetically effective population sizes of brooding species<br />

is important. Effective population sizes in hermaphroditic reef corals are expected to be several<br />

magnitudes smaller than the census size, due to inter-annual variation in census population sizes<br />

and fecundity, as well as possible influences of both asexual reproduction and self-fertilization.<br />

Analysis of highly polymorphic DNA markers of the brooding coral, Seriatopora hystrix, on the<br />

Great Barrier Reef (GBR) shows that allelic diversity is high across the GBR, but much smaller<br />

in each population, suggestive of small effective population sizes. Heterozygote deficits,<br />

indicative of non-random mating, are common in this species, which is consistent with rapid<br />

settlement of the larvae shortly after release. Knowledge of fine-scale connectivity patterns<br />

within populations of brooding corals may help to elucidate the broad-scale patterns in genetic<br />

structure. Limited sperm dispersal may amplify signals of geographic subdivision, but current<br />

knowledge of the frequency and scale of dispersal of spermatozoa in brooding species is<br />

limited, and is absent for S. hystrix. To determine the spatial extent of spermatozoa dispersal,<br />

the genotypes of all colonies within a mapped study population in the Palm Islands, central<br />

GBR, were compared with those of the brooded larvae of adults sampled from the center of the<br />

mapped population. Furthermore, we assessed the timing of spermatozoa and larval release<br />

with histological monitoring of adult gametogenic tissue throughout the reproductive season.<br />

119

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