Proceedings fo the Seventeenth Annual Sea Turtle Symposium, 4-8 March 1997, Orlando, Florida, U.S.A.

The 17th Annual Sea Turtle Symposium was held at the Delta Orlando Resort in Orlando, Florida U.S.A. from March 4-8, 1997. The symposium was hosted by Florida Atlantic University, Mote Marine Laboratory, University of Central Florida, University of Florida, Florida Atlantic University and the Comité Nacional para la Conservación y Protección de las Totugas Marinas. The 17th was the largest symposium to date. A total of 720 participants registered, including sea turtle biologists, students, regulatory personnel, managers, and volunteers representing 38 countries. In addition to the United States, participants represented Australia, Austria, the Bahamas, Bonaire, Bermuda, Brazil, Canada, Colombia, Costa Rica, Croatia, Cuba, Cyprus, Dominican Republic, Ecuador, England, Guatemala, Greece, Honduras, India, Italy, Japan, Madagascar, Malaysia, Mexico, The Netherlands, Nicaragua, Peru, Philippines, Republic of Seychelles, Scotland, Spain, Sri Lanka, Switzerland, Taiwan, Turkey, Uruguay, and Venezuela. In addition to the 79 oral, 2 video, and 120 poster presentations, 3 workshops were offered: Selina Heppell (Duke University Marine Laboratory) provided “Population Modeling,” Mike Walsh and Sam Dover (Sea World-Orlando) conducted “Marine Turtle Veterinary Medicine” and “Conservation on Nesting Beaches” was offered by Blair Witherington and David Arnold (Florida Department of Environmental Protection). On the first evening, P.C.H. Pritchard delivered a thoughtful retrospect on Archie Carr that showed many sides of a complex man who studied and wrote about sea turtles. It was a presentation that none of us will forget. The members considered a number of resolutions at the Thursday business meeting and passed six. Five of these resolutions are presented in the Commentaries and Reviews section of Chelonian Conservation and Biology 2(3):442-444 (1997). The symposium was fortunate to have many fine presentations competing for the Archie Carr Best Student Presentations awards. The best oral presentation award went to Amanda Southwood (University of British Columbia) for “Heart rates and dive behavior of the leatherback sea turtle during the internesting interval.” The two runners-up were Richard Reina (Australian National University) for “Regulation of salt gland activity in Chelonia mydas” and Singo Minamikawa (Kyoto University) for “The influence that artificial specific gravity change gives to diving behavior of loggerhead turtles”. The winner of this year’s best poster competition was Mark Roberts (University of South Florida) for his poster entitled “Global population structure of green sea Turtles (Chelonia mydas) using microsatellite analysis of male mediated gene flow.” The two runners-up were Larisa Avens (University of North Carolina-Chapel Hill) for “Equilibrium responses to rotational displacements by hatchling sea turtles: maintaining a migratory heading in a turbulent ocean” and Annette Broderick (University of Glasgow) for “Female size, not length, is a correlate of reproductive output.” The symposium was very fortunate to receive a matching monetary and subscription gift from Anders J. G. Rhodin of the Chelonian Research Foundation. These enabled us to more adequately reward the fine work of students. The winners of the best paper and best poster awards received $400 plus a subscription to Chelonian Conservation and Biology. Each runner up received $100. The symposium owes a great debt to countless volunteers who helped make the meeting a success. Those volunteers include: Jamie Serino, Alan Bolton, and Karen Bjorndal, along with the UF students provided audio visual help, John Keinath chaired the student awards committee, Mike Salmon chaired the Program Commiteee, Sheryan Epperly and Joanne Braun compiled the Proceedings, Edwin Drane served as treasurer and provided much logistical help, Jane Provancha coordinated volunteers, Thelma Richardson conducted registration, Vicki Wiese coordinated food and beverage services, Jamie Serino and Erik Marin coordinated entertainment, Kenneth Dodd oversaw student travel awards, Traci Guynup, Tina Brown, Jerris Foote, Dan Hamilton, Richie Moretti, and Vicki Wiese served on the time and place committee, Blair Witherington created the trivia quiz, Tom McFarland donated the symposium logo, Deborah Crouse chaired the resolutions committee, Pamela Plotkin chaired the nominations committee, Sally Krebs, Susan Schenk, and Larry Wood conducted the silent auction, and Beverly and Tom McFarland coordinated all 26 vendors. Many individuals from outside the United States were able to attend the 17th Annual Sea Turtle Symposium thanks to the tireless work of Karen Eckert, Marydele Donnelly, and Jack Frazier in soliciting travel assistance for a number of international participants. We are indebted to those donating money to the internationals’ housing fund (Flo Vetter Memorial Fund, Marinelife Center of Juno Beach, Roger Mellgren, and Jane Provancha). We raise much of our money for international travel from the auction; thanks go to auctioneer Bob Shoop, who kept our auction fastpaced and entertaining, and made sure the bidding was high. The Annual Sea Turtle Symposium is unequaled in its emphasis on international participation. Through international participation we all learn a great deal more about the biology of sea turtles and the conservation issues that sea turtles face in distant waters. Additionally, those attending the symposium come away with a tremendous wealth of knowledge, professional contacts, and new friendships. The Annual Sea Turtle Symposium is a meeting in which pretenses are dropped, good science is presented, and friendly, open communication is the rule. The camaraderie that typifies these meetings ultimately translates into understanding and cooperation. These aspects, combined, have gone and will go a long way toward helping to protect marine turtles and toward aiding their recovery on a global scale. (PDF contains 342 pages)

Importance de certaines caractéristiques biologiques dans la structuration génétique des espèces de poissons: le cas de Ethmalosa fimbriata et Sarotherodon melanotheron

Six populations of Ethmalosa fimbriata and six of Sarotherodon melanotheron have been analysed using enzymatic electrophoresis. The study of gene flow intensity in these two species indicate that: - In Ethmalosa fimbriata, a migratory species with high fecundity and pelagic eggs, there is a high gene flow between populations (3 Nm 83). - In Sarotherodon melanotheron, a sedentary and mouthbrooder species with low fecundity, there is a low gene flow between populations (1 Nm 4).

Genetic and morphological differences between Sebastes vulpes and S. zonatus (Teleostei: Scorpaeniformes: Scorpaenidae)

The taxonomic status of Sebastes vulpes and S. zonatus were clarified by comprehensive genetic (amplif ied fragment length polymorphisms [AFLP] and mitochondrial DNA [mtDNA] variation) and morphological analyses on a total of 65 specimens collected from a single locality. A principal coordinate analysis based on 364 AFLP loci separated the specimens completely into two genetically distinct groups that corresponded to S. vulpes and S. zonatus according to body coloration and that indicated that they are reproductively isolated species. Significant morphological differences were also evident between the two groups; 1) separation by principal component analysis based on 31 measurements, and 2)separation according to differences in counts of gill rakers and dorsal-fin spines without basal scales, and in the frequencies of specimens with small scales on the lower jaw. Restriction of gene flow between the two groups was also indicated by the pairwise ΦST values estimated from variations in partial sequences from the mtDNA control region, although the minimum spanning network did not result in separation into distinct clades. The latter was likely due to incomplete lineage sorting between S. vulpes and S. zonatus owing to their recent speciation.

Systematics of the North American menhadens: molecular evolutionary reconstructions in the genus Brevoortia (Clupeiformes: Clupeidae)

Evolutionary associations among the four North American species of menhadens (Brevoortia spp.) have not been thoroughly investigated. In the present study, classifications separating the four species into small-scaled and large-scaled groups were evaluated by using DNA data, and genetic associations within these groups were explored. Specifically, data from the nuclear genome (microsatellites) and the mitochondrial genome (mtDNA sequences) were used to elicit patterns of recent and historical evolutionary associations. Nuclear DNA data indicated limited contemporary gene flow among the species, and also indicated higher relatedness within the small-scaled and large-scaled menhadens than between these groups. Mitochondrial DNA sequences of the large-scaled menhadens indicated the presence of two ancestral lineages, one of which contained members of both species. This result may indicate genetic diver-gence (reproductive isolation) followed by secondary contact (hybridization) between these species. In contrast, a single ancestral lineage indicated incomplete genetic divergence between the small-scaled menhaden. These results are discussed in the context of the biology and demographics of each species.

Pacific Salmon, Oncorhynchus spp., and the Definition of "Species" Under the Endangered Species Act

For purposes ofthe Endangered Species Act (ESA), a "species" is defined to include "any distinct population segment of any species of vertebrate fish or wildlife which interbreeds when mature. "Federal agencies charged with carrying out the provisions of the ESA have struggled for over a decade to develop a consistent approach for interpreting the term "distinct population segment." This paper outlines such an approach and explains in some detail how it can be applied to ESA evaluations of anadromous Pacific salmonids. The following definition is proposed: A population (or group of populations) will be considered "distinct" (and hence a "species ")for purposes of the ESA if it represents an evolutionarily significant unit (ESU) of the biological species. A population must satisfy two criteria to be considered an ESU: 1) It must be substantially reproductively isolated from other conspecific population units, and 2) It must represent an important component in the evolutionary legacy of the species. Isolation does not have to be absolute, but it must be strong enough to permit evolutionarily important differences to accrue in different population units. The second criterion would be met if the population contributes substantially to the ecological/genetic diversity of the species as a whole. Insights into the extent of reproductive isolation can be provided by movements of tagged fish, natural recolonization rates observed in other populations, measurements of genetic differences between populations, and evaluations of the efficacy of natural barriers. Each of these methods has its limitations. Identification of physical barriers to genetic exchange can help define the geographic extent of distinct populations, but reliance on physical features alone can be misleading in the absence of supporting biological information. Physical tags provide information about the movements of individual fish but not the genetic consequences of migration. Furthermore, measurements ofc urrent straying or recolonization rates provide no direct information about the magnitude or consistency of such rates in the past. In this respect, data from protein electrophoresis or DNA analyses can be very useful because they reflect levels of gene flow that have occurred over evolutionary time scales. The best strategy is to use all available lines of evidence for or against reproductive isolation, recognizing the limitations of each and taking advantage of the often complementary nature of the different types of information. If available evidence indicates significant reproductive isolation, the next step is to determine whether the population in question is of substantial ecological/genetic importance to the species as a whole. In other words, if the population became extinct, would this event represent a significant loss to the ecological/genetic diversity of thes pecies? In making this determination, the following questions are relevant: 1) Is the population genetically distinct from other conspecific populations? 2) Does the population occupy unusual or distinctive habitat? 3) Does the population show evidence of unusual or distinctive adaptation to its environment? Several types of information are useful in addressing these questions. Again, the strengths and limitations of each should be kept in mind in making the evaluation. Phenotypic/life-history traits such as size, fecundity, and age and time of spawning may reflect local adaptations of evolutionary importance, but interpretation of these traits is complicated by their sensitivity to environmental conditions. Data from protein electrophoresis or DNA analyses provide valuable insight into theprocessofgenetic differentiation among populations but little direct information regarding the extent of adaptive genetic differences. Habitat differences suggest the possibility for local adaptations but do not prove that such adaptations exist. The framework suggested here provides a focal point for accomplishing the majorgoal of the Act-to conserve the genetic diversity of species and the ecosystems they inhabit. At the same time, it allows discretion in the listing of populations by requiring that they represent units of real evolutionary significance to the species. Further, this framework provides a means of addressing several issues of particular concern for Pacific salmon, including anadromous/nonanadromous population segments, differences in run-timing, groups of populations, introduced populations, and the role of hatchery fish.

The geographic basis for population structure in Fraser River chinook salmon (Oncorhynchus tshawytscha)

We surveyed variation at 13 microsatellite loci in approximately 7400 chinook salmon sampled from 52 spawning sites in the Fraser River drainage during 1988–98 to examine the spatial and temporal basis of population structure in the watershed. Genetically discrete chinook salmon populations were associated with almost all spawning sites, although gene flow within some tributaries prevented or limited differentiation among spawning groups. The mean FST value over 52 samples and 13 loci surveyed was 0.039. Geographic structuring of populations was apparent: distinct groups were identified in the upper, middle, and lower Fraser River regions, and the north, south, and lower Thompson River regions. The geographically and temporally isolated Birkenhead River population of the lower Fraser region was sufficiently genetically distinctive to be treated as a separate region in a hierarchial analysis of gene diversity. Approximately 95% of genetic variation was contained within populations, and the remainder was accounted for by differentiation among regions (3.1%), among populations within regions (1.3%), and among years within populations (0.5%).Analysis of allelic diversity and private alleles did not support the suggestion that genetically distinctive populations of chinook salmon in the south Thompson were the result of postglacial hybridization of ocean-type and stream-type chinook in the Fraser River drainage. However, the relatively small amount of differentiation among Fraser River chinook salmon populations supports the suggestion that gene flow among genetically distinct groups of postglacial colonizing groups of chinook salmon has occurred, possibly prior to colonization of the Fraser River drainage.

Allozyme and RAPD variation in the eastern Pacific yellowfin tuna (Thunnus albacares)

Stock structure of eastern Pacific yellowfin tuna was investigated by analyzing allozymes and random amplified polymorphic DNAs (RAPDs) from 10 samples of 20–30 individuals each, collected between 1994 and 1996 from fishing vessels operating in the Inter-American Tropical Tuna Commission (IATTC) yellowfin regulatory area (CYRA). Allozyme analysis resolved 28 loci, eight of which were polymorphic under the 0.95 criterion: Aat-S*, Glud, Gpi-F*, Gpi-S*, La, Lgg, Pap-F*, and 6-Pgd, resulting in a mean heterozygosity over all allozyme loci of H = 0.052. Four polymorphic RAPD loci were selected for analysis, resulting in a mean heterozygosity of H = 0.43. Eight of 45 pairwise comparisons of allozyme allele frequencies among the ten samples showed significant differences after correction for multiple testing (P<0.0001), all of which involved comparisons with the Gulf of California sample. Confirmation of this signal of population structure would have management implications. No significant divergence in RAPD allele frequencies was observed among samples. Weir and Cockerham θ estimated for allozyme loci (θ=0.048; P<0.05) and RAPD loci (θ=0.030; P>0.05) revealed little population structure among samples. Mantel tests demonstrated that the genetic relationships among samples did not correspond to an isolation-by-distance model for either class of marker. Four of eight comparisons of coastal and offshore samples revealed differences of allele frequencies at the Gpi-F* locus (P<0.05), although none of these differences was significant after correction for multiple testing (P>0.001). Results are consistent with the hypothesis that the CYRA yellowfin tuna samples comprise a single genetic stock, although gene flow appears to be greater among coastal samples than between coastal and offshore samples.

Population structure of king mackerel (Scomberomorus cavalla) around peninsular Florida, as revealed by microsatellite DNA

A total of 1006 king mackerel (Scomberomorus cavalla) representing 20 discrete samples collected between 1996 and 1998 along the east (Atlantic) and west (Gulf) coasts of Florida and the Florida Keys were assayed for allelic variation at seven nuclear-encoded microsatellites. No significant deviations from Hardy-Weinberg equilibrium expectations were found for six of the microsatellites, and genotypes at all microsatellites were independent. Allele distributions at each microsatellite were independent of sex and age of individuals. Homogeneity tests of spatial distributions of alleles at the microsatellites revealed two weakly divergent “genetic” subpopulations or stocks of king mackerel in Florida waters—one along the Atlantic coast and one along the Gulf coast. Homogeneity tests of allele distributions when samples were pooled along seasonal (temporal) boundaries, consistent with the temporal boundaries used currently for stock assessment and allocation of the king mackerel resource, were nonsignificant. The degree of genetic divergence between the two “genetic” stocks was small: on average, only 0.19% of the total genetic variance across all samples assayed occurred between the two regions. Cluster analysis, assignment tests, and spatial autocorrelation analysis did not generate patterns that were consistent with either geographic or spatial-temporal boundaries. King mackerel sampled from the Florida Keys could not be assigned unequivocally to either “genetic” stock. The genetic data were not consistent with current spatial-temporal boundaries employed in stock assessment and allocation of the king mackerel resource. The genetic differences between king mackerel in the Atlantic versus those in the Gulf most likely stem from reduced gene flow (migration) between the Atlantic and Gulf in relation to gene flow (migration) along the Atlantic and Gulf coasts of peninsular Florida. This difference is consistent with findings for other marine fishes where data indicate that the southern Florida peninsula serves (or has served) as a biogeographic boundary.

Genetic diversity of Bartail flathead (Platycephalus indicus (Linnaeus,1758)) using AFLP markers in Persian Gulf

Platycephalus indicus is a large benthic fish that inhabits temperate and tropical coastal waters of the Indo-West Pacific and found on sand or mud bottom in vary shallow area of estuary and near shore to depth of 25m. This species is dominant species of platycephalidae family, in Khuzestan, Bushehr and Hormozgan provinces and mainly is captured by bottom trawl, gillnet and moshta in Hormozgan. This study was designed to evaluate population variation and differentiation of bartail flathead (Platycephalus indicus (Linnaeus, 1785))in the Iranian waters of Persian Gulf using the morphometric and meristic characters and by AFLP marker. . A total 180 fish specimens were collected by gill net from six station(khor mosa, bahrekan, shif, motaf, charak and bandar abbas) that was 30 individual related to every station in Iranian shores of Persian Gulf . 28 morphometric factors and 11meristic specialties were measured and morphometric factors was standardized with Beacham formula. Univariate analysis of variance (One-way ANOVA) revealed significant differences with varying degrees between the means for 21 standardized morphometric measurements and 6 meristic counts that showed high significant differences between the six stations sampling. Discriminate function analysis (DFA) or the overall random assignment of individuals into their original groups was for morphometric and meristic characters was 47.9% and 53.9% respectively. The data were subjected to a principle component analysis (PCA) which grouped in eight and four factors for morphometric and meristic charactersrespectively.. Genetic diversity of six populations of bartail flathead (Platycephalus indicus) was investigated using amplified fragment length polymorphism (AFLP). A total of 118 reproducible bands amplified with ten AFLP primer combinations were obtained from 42 fishes that were collected from six different locations in the northern of Persian Gulf. The percentage of polymorphic bands was 57.06%. Average of Nei’s genetic diversity was 0.200±0.008, and Average of Shannon’s index was 0.300±0.011. The results of AMOVA analysis indicated that 66% of the genetic variation contained within populations and 34% occurred among populations and gene flow was 0.6454.The estimated level of population differentiation asmeasured by average Fst value across all loci was 0.327. Plotting discriminant functions 1 and 2 and UPGMA dendrograms based on Euclidian distance and genetic distance also showed at least five separate populations of bartail flathead in the northern Persian Gulf.

Connectivity of coral reefs between marine park and non-marine park islands in the Malacca Straits

This study investigates the genetic population and gene flow in the clownfish (Amphiprion ocellaris), across the Langkawi and Payar Archipelago by analysis of molecular markers in the mitochondrial region.

Genetic viability of Nabugabo lakes (LVR satellite lakes) fish species

Natural populations of fish species in Lake Victoria Region (LVR) have under gone dramatic changes including severe reduction in sizes, division of original stocks into disjunct subunits, and segregation into several isolated population units either within a single water body or even worse into separate waters. In addition, these changes have been either preceded or precipitated by introductions of non-indigenous species that out competed the native forms and in case of closely related species genetically swamped them through hybridisation. The latter is especially the case in Nabugabo lakes. Such events lead to fragmentation of populations, which results in reduction in genetic diversity due to genetic drift, inbreeding and reduced or lack of gene flow among independent units. Such phenomena make the continued existence of fisheries stocks in the wild precarious, more so in the face of the competition from exotic species. Species introductions coupled with growing exploitation pressure of the fisheries of these lakes have put the native stocks at risk. Nabugabo lakes harbor cichlid species that are unique to these lakes more so species of the cichlid complex. In this paper the ecological status and genetic viability of key Nabugabo lakes fish species is examined and management options are discussed.