A “Precaução Padrão”
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ABSTRACTS – 2007 JOINT MEETING OF ICHTHYOLOGISTS & HERPETOLOGISTS COMPLIED BY M.A. DONNELLY (for co-authored abstracts, underlined name = presenter) Abrams, Alyssa Pheromone Production and Volatility in the Copperhead (Agkistrodon contortrix) in Captivity Saint Louis University, St. Louis, MO, United States Snakes were collected during the summer in central Missouri and maintained in captivity at Washington University's Tyson Research Center. Snakes were maintained at 24oC and fed weekly. Beginning in late August females were tested for the presence of pheromones. Male courtship behaviors served as the bioassay for pheromone presence. All experiments were conducted in an outdoor arena lined with a disposable plastic liner. Volatility of pheromones was measured by placing the female in a clean opaque plastic container, containing 3-3mm diameter holes, on a six cm pedestal in the arena containing one male. Male behavior was observed for 30 min after which the female was removed and placed directly in the arena to determine her attractivity. All eight females tested elicited some male courtship behaviors during at least some trials. All males responded to attractive females. Males showed no interest in other males. Male behaviors included: tongue flicking, trailing, head jerking, head bobbing, head poking and tail searching. No mating was observed. In three trials, males were attracted to the cages containing the females, indication the attractivity pheromone may be volatile, however, in tests using skin wipes from attractive females no males responded. An immediately post-partum female was attractive to males. ______________________________________________________________________________ Adams, Cory; Saenz, Daniel; Pierce, Josh Anuran Use of Primary Successional Ponds USDA Forest Service, Southern Research Station, Nacogdoches, TX, United States Freshwater habitats exist along a continuum ranging from short duration ephemeral sites to permanent bodies of water. The current paradigm regarding these aquatic communities suggest that as water bodies become more permanent they have higher predator densities and greater predator richness. The longer a body of water persists in the environment the more predators will colonize and use that body of water. Thus we suggest, newly formed ponds should undergo changes in predator composition as the ponds age. Indirectly, tadpole (anuran larvae) richness and density also should be affected by the age of the pond. We sampled 8 ponds from 2001 – 2006 daily using funnel traps to document successional changes in species composition through time. Half of the ponds were created in 1992 and half in 2000. We found that tadpole densities were higher in the early successional ponds, and that the newer ponds showed considerable turnover in species composition as the ponds aged. However, community assembly in older ponds remained relatively constant suggesting maturity and stabilization. 1 Adams, Dean Organization of Plethodon Salamander Communities: Interspecific Competition and Guild-Based Community Assembly Iowa State University, Ames, IA, United States A long-standing goal in evolutionary ecology is to determine whether the organization of communities is reflective of underlying deterministic processes. Over the past several decades, intensive research on select Plethodon communities has documented the effects of species interactions, and taken together these studies suggest that competition may be widespread. Nevertheless, while competition is widely assumed to be prevalent, this hypothesis has not been rigorously tested. In this study, I examined patterns of species co-occurrence among the 45 species of eastern Plethodon from 4,540 geographic sites. Using a guild-based model of community assembly, I found that patterns of community composition are consistent with a model of competitive-based community assembly. These findings imply that larger Plethodon communities are assembled from simpler communities in a manner consistent with what is predicted through competitive mechanisms, and suggest that stable species combinations are possible to achieve at various levels of species richness. When combined with previous work on this genus, these results also provide strong evidence consistent with the hypothesis that competitive-based community assembly is a general phenomenon in Plethodon, and that interspecific competition is prevalent among the eastern species of this group. _____________________________________________________________________ Adams, Michael1; Cole, Rebecca 2; Rachowicz, Lara 3 Occurrence and Prevalence of the Pathogen, Batrachochytrium dendrobatidis, in Oregon and Northern California Anurans 1USGS, Corvallis, OR, United States, 2USGS, Madison, WI, United States, 3Yosemite National Park, El Portal, CA, United States Batrachochytrium dendrobatidis is a fungus that is pathogenic to amphibians. It has been associated with amphibian declines around the world but there is little information on its distribution or the factors that affect its pathogenicity. We conducted a two year study of the distribution and prevalence of B. dendrobatidis in Oregon and Northern California. We used a standard rtPCR technique to detect the presence of B. dendrobatidis spores on swabs that were rubbed over the skin, toes, and mouth of live animals in the field. We detected B. dendrobatidis on 219 out of 1944 native and introduced anurans sampled and at 57 out of 146 populations sampled. Our preliminary analysis using occupancy models suggests the probability that a native anuran was infected, given that B. dendrobatidis is present in the population, increased with developmental stage, a human activity index, and elevation, and decreased within the range of introduced bullfrogs (Rana catesbeiana). Occupancy models also suggest that we failed to detect B. dendrobatidis at many sites where it was present. This analysis estimates that B. dendrobatidis was present in 56% (CI = 46 2 — 67%) of native populations sampled and 67% (CI = 50 – 88%) of bullfrog populations sampled. ______________________________________________________________________________ Adler, Kraig Herpetological Exploration in the 18th Century: Spanning the Globe with Linnaeus’s Students Cornell University, Ithaca, NY, United States Carl Linnaeus's travels as an explorer were limited to the Scandinavian provinces. He had opportunities to visit more exotic places but arranged instead to send his young pupils. During the period 1748 to 1779 they collectively visited nearly every continent including Australia. More than 20 of them went overseas and one-third died in the effort. Among those of particular herpetological interest were Pehr Forsskål and Fredrik Hasselquist (Middle East), Pehr Kalm (Russia and North America), Pehr Löfling (Spain and northern South America), Pehr Osbeck (China), Anders Sparrman (Cape Colony and a circumnavigation with Captain James Cook that included New Zealand, the South Pacific, and within the Antarctic Circle to 71˚10' South), and C. P. Thunberg (Cape Colony, Ceylon, Java, and Japan) who eventually succeeded to his master's chair in Uppsala. Most of these expeditions were primarily botanical and even commercial, but numerous specimens of amphibians and reptiles were collected that served as types for many new species described by Linnaeus, his students, and others. ______________________________________________________________________________ Adreani, Mia Context-Dependent Streak Spawning in the Hermaphroditic Seabass, Serranus subligarius Florida State University, Tallahassee, FL, United States In the simultaneously hermaphroditic marine fish, Serranus subligarius, male role individuals are known to pair spawn, group spawn and streak spawn. These mating strategies are common among marine reef fish and their spawning behavior has been well studied. What is unclear is how each behavior translates into reproductive success and how these competing strategies may affect fertilization success. The variation in success of each strategy may pinpoint tradeoffs with other aspects of their reproductive ecology such as territory acquisition, body condition and spawning frequency. In addition to studying aspects of their mating strategies, environmental contexts under which streaking occurs have been explored. While density is known to increase the incidence of streaking in this species, it is not well understood how factors such as habitat type and small-scale demographic dynamics affect the mating system. Mating behaviors were recorded during the summers of 2005 and 2006 at three sites with different local population densities within St. Andrew’s State Park, Panama City, Florida. Focal individuals were each observed in 15-minute increments and the following were recorded: total number of spawns, number of streak spawns, location along transect, habitat type, relative size of individuals. Results suggest that seasonality plays a role in the incidence of 3 alternative mating strategies, whereby sharp increases in the frequency of streak spawning occur late in the spawning season (late August-early September). Habitat type (i.e. algal cover), coupled with high variation in body size in the local population, also appears to be important in the success of streaking by small individuals. This may be the result of increased algal growth late in the season providing adequate refuge for small individuals, and may also indicate the timing of onset of sexual maturity among newly recruited individuals. These ideas are currently being