ABSTRACTS – 2008 JOINT MEETING OF ICHTHYOLOGISTS & HERPETOLOGISTS COMPLIED BY M.A. DONNELLY (underlined name = presenter) Kneebone to Ristovska 0494 AES Age & Growth/Reproduction, Kafka/LeMaratine, Saturday July 26, 2008 Using Bomb Radiocarbon Analyses to Validate Age and Growth Estimates for the Tiger Shark, Galeocerdo cuvier, in the Western North Atlantic Jeff Kneebone1, Lisa Natanson2, Allen Andrews3, Hunt Howell1 1University of New Hampshire, Durham, NH, United States, 2National Marine Fisheries Service, Narragansett, RI, United States, 3Moss Landing Marine Laboratories, Moss Landing, CA, United States Refined and validated age and growth determinations are necessary for a proper understanding of tiger shark (Galeocerdo cuvier) life history characteristics in the western North Atlantic. Age and growth estimates were derived from band counts of 238 sectioned vertebral centra. Bomb radiocarbon analysis of ten band pairs extracted from four vertebral sections suggested band pairs are deposited annually up to age 20. Males and females were aged to 20 and 22 years, respectively, although longevity estimates predict maximum ages of 27 and 29 years, respectively. Two and three-parameter von Bertalanffy and Gompertz growth functions fit to length at age data demonstrated that growth rates were similar for males and females up to around 200 cm FL after which male growth slowed. Both sexes appear to reach maturity at age 10. The two-parameter von Bertalanffy growth function provided the best biological fit to length at age data generating parameter estimates of: L∞ = 330 cm FL, k = 0.131 for males and L∞ = 347 cm FL, k = 0.124 for females, with L0 set at 62 cm FL. This study provides a rigorous description of tiger shark age and growth in the western North Atlantic and further demonstrates the utility of bomb radiocarbon as an age validation tool for elasmobranch fish. ___________________________________________________________________________ 0184 Fish Ecology I, Drummond, Thursday July 24, 2008 Using Fine Scale GIS Data To Quantify Microhabitat Use And Environmental Niche Characteristics Of Stream Fishes Jason Knouft Saint Louis University, St. Louis, Missouri, United States The application of geographic information systems (GIS) data to the study of abiotic factors regulating broad scale species distributions has recently received a large amount of attention. Although these applications have provided important insights into factors influencing species distributions, limited use of niche-based GIS techniques have been made in local habitats. Aquatic systems provide excellent opportunities for fine scale GIS applications because sites can be easily defined and the environmental factors regulating taxa in these systems are well understood. For this study, a 700 meter segment of Labarque Creek, a second order stream located on the property of the Washington University Tyson Research Center in eastern Missouri, was mapped using a high accuracy (<20 cm) Trimble GeoXH GPS unit. Georeferenced data for nine habitat variables characterizing depth, temperature, dissolved oxygen, sediment size, flow rate and riparian canopy cover were collected at over 200 points along the 700 meter stream segment. Continuous raster datasets were generated using an inverse distance weighting algorithm for each variable. Fishes were then collected at georeferenced localities along the stream reach. Fish occurrence localities were intersected with environmental datasets to characterize the habitat of each species along the stream reach. This method was able to discriminate habitat use among closely related species (e.g., within Lepomis) as well as differentiate between ‘pool’ and ‘riffle’ species. Niche breadth and niche marginality were also calculated for each species to characterize the habitat use for all taxa in relation to available habitat. Species’ niche breadth and niche marginality were both correlated with number of individuals collected, indicating that species with narrow niche breadths and/or marginal niches tend to be less abundant. Results suggest that the application of broad scale GIS-based niche characterization techniques can be useful for understanding patterns and processes in local systems. ___________________________________________________________________________ 0522 Herp Stressors/Snake Conservation, Salon 6&7, Monday July28, 2008 Amphibians of Brooktrout Lake: A “Recovering” Acidified Lake in the Adirondacks Mary Beth Kolozsvary1, Clifford Siegfried2 1NYS Biodiversity Research Institute, New York State Museum, Albany, NY, United States, 2New York State Museum, Albany, NY, United States Brooktrout Lake is a high elevation lake located in the southwestern Adirondack mountains. During the latter half of the last century, pH of the lake measured <5, which was typical of acidified clear water lakes in the region during that time period. Over the last decade, long term monitoring of water chemistry indicated signs of recovery from acidified conditions. In 2005–2007, amphibian communities were sampled using minnow traps, activity traps, and dip net sweeps to assess species composition, relative abundance, and reproductive success. Seven amphibian species were documented, with 6 of these species showing successful reproduction. The most abundant amphibians at the site were red-spotted newts (Notophthalmus viridescens viridescens) and green frogs (Lithobates clamitans). In November 2005, brook trout (Salvelinus fontinalis) were stocked into the fishless lake (which contained brook trout prior to acidification). Subsequent to the restocking, stomach contents of red- spotted newts and brook trout were sampled to determine degree of dietary overlap and to monitor changes in relation to fish introduction. Preliminary analysis indicates that newt diet varied throughout the year and was more diverse than trout diet. In October 2006 and May 2007, stomach samples from trout were dominated by Chaoborus (larvae and pupae). In October 2007 samples, Chaoborus were present, but not as abundant as in the previous year. Year class trout consumed corixids and zygopterans; fish of larger size classes consumed anisopterans as well. Activity traps are also being used to monitor invertebrate community changes over time, in response to changes in water chemistry and biological communities, including brook trout populations. ___________________________________________________________________________ 0070 Fish Systematics II, Salon A&B, Friday July 25, 2008 Review of Melanochromis, a Cichlid Genus of Lake Malawi, with the Description of Three New Species Gertrud Konings1, Adrianus Konings3, Jay Stauffer Jr2 1El Paso Community College, El Paso, TX, United States, 2Penn State University, University Park, PA, United States, 3Cichlid Press, El Paso, TX, United States Trewavas (1935) originally distinguished the Lake Malawi cichlid genus Melanochromis from Pseudotropheus on the basis of morphology and arrangement of pharyngeal teeth and included five species in the genus. Later, Trewavas (1984) extended the diagnosis to include all elongate mbuna that possessed horizontal stripes and U-shaped tooth bands. We have examined the type specimens of M. mellitus (Johnson), M. robustus (Johnson), M. loriae (Johnson), and M. chipokae (Johnson) and discuss their taxonomy. We have extended the diagnosis of the genus, suggest reassigning seven species that do not show the characteristic melanin pattern and describe three new species from the eastern shore of the lake totalling the number of species of Melanochromis to 14. ___________________________________________________________________________ 0515 Fish Morphology & Histology II, Salon 6&7, Saturday July 26, 2008 The Evolution of Raking Prey-processing in Teleosts Fishes Nicolai Konow, Ariel Camp, Christopher Sanford Department of Biology, Hofstra University, Hempstead NY, United States We investigated raking, a derived feeding behavior involving a novel tongue-bite apparatus (TBA), which occurs in two major teleost lineages, the osteoglossomorph (bony-tongues) and salmonid fishes. Clear differences were quantified at several organizational levels of form and function that may have caused the different evolutionary patterns observed within each lineage in the diversification of raking behaviors. All salmonids studied to date are characterized by a conservative TBA morphology and by having distinctly stereotypical rakes, both at the level of muscle activity and kinematics. In contrast, osteoglossomorphs are highly diverse at all levels and split into two distinct evolutionary lineages, each showing unique traits in their raking functional morphology. Osteoglossid arowanas employ a complex prey- compressing raking behavior, while notopterid knife fishes shred their prey using highly divergent kinematics, even among closely related taxa. At the level of muscle- activity, a pronounced variability in activity-patterns among osteoglossomorphs facilitate several pathways of modulation. In combination with divergent TBA morphology, modulation of raking muscle activity appears to have shaped the evolution of different raking behaviors both within this lineage and compared to salmonids. Using evidence from TBA osteology, myology and biomechanics, raking muscle activity and kinematics, and information on behavioral and neuro-motor control of prey processing, we illustrate how the interplay between form and function has shaped convergent as well as divergent raking behaviors among these basal bony fishes. Supported by NSF IOB 0444891,