Digital Commons Network^™

Evaluating The Use Of Roving Diver And Transect Surveys To Assess The Coral Reef Fish Assemblage Off Southeastern Hispaniola, Emily Schmitt Lavin, Robert Sluka, Kathleen Sullivan-Sealey

Emily F Schmitt Lavin

The relatively little-studied fish fauna off southeastern Hispaniola was rapidly assessed using a combination of visual survey techniques including transects and roving diver surveys. It was found that when combined, both methods provided a more complete overall species assessment than either method was able to provide in isolation. Being able to conduct rapid species assessments is becoming increasingly more important as a conservation tool. Data on species composition, sighting frequency, and abundance of all fishes were collected using both methods. Abundance was recorded in four logarithmic-based categories (roving diver method) while the number of fishes were counted within 40-m2 transects …

Managed Areas As Ecological Traps For Snakes In An Exotic Plant-Invaded Landscape, Evin Carter, Bruce Kingsbury

Bruce A Kingsbury Ph.D.

Areas such as wildlife refuges or parks offer important opportunities for the protection of imperiled wildlife. Unfortunately, conflicting practices and objectives with respect to natural resource management and general property management can potentially lead to negative outcomes such as the decline or extirpation local flora or fauna. Here, we provide direct evidence of the impacts of property management and restoration activities on a population of Northern Copperheads ( Agkistrodon contortrix mokasen ) in southern Indiana, showing that several managed habitats can and do attract Northern Copperheads and simultaneously place them at greater risk of injury and/or mortality. At the same …

Density And Cover Preferences Of Black-And-Rufous Elephant-Shrews (Rhynchocyon Petersi) In Chome Forest Reserve, Tanzania, Stephanie Coster, David Ribble

David O Ribble

The objective of this study was to determine the density and habitat preference of the Black-andrufous elephant-shrew (Rhynchocyon petersi) in Chome Forest Reserve, Tanzania. Chome Forest (143km2) is located in the South Pare Mountains and provides critical habitat for endangered R. petersi. Twelve 300m transects were cut through the centre of the forest in an east-west direction and the number of elephant-shrew nests within 2.5 meters on each side of the transects was recorded. The mean number of nests per 100m transect (0.39 ± 0.47 [1SE]) translated to a density estimate of 19 elephant-shrews per km2 (SE=23). Nest sites tended …

Effects Of Population Size And Density On Pollinator Visitation, Pollinator Behavior, And Pollen Tube Abundance In Lupinus Perennis, Christopher Bernhardt, Randall Mitchell, Helen Michaels

Randall J. Mitchell

Both the number and the density of flowering plants in a population can be important determinants of pollinator abundance and behavior. We report the joint effects of population size and density on pollinator visitation and pollination success for Lupinus perennis (Fabaceae). Focusing on five pairs of populations, we matched one small population (125-800 flowering plants) with one distinctly larger population (1000-3000 flowering plants). In these pairs, population size did not affect pollinator communities or pollination success. All measures of pollination success increased significantly with density. Only bee behavior (number of flowers probed per inflorescence) exhibited a significant interaction of size …

Effects Of Natural Flooding And Manual Trapping On The Facilitation Of Invasive Crayfish-Native Amphibian Coexistence In A Semi-Arid Perennial Stream, Lee Kats, Gary Bucciarelli, Thomas Vandergon, Rodney Honeycutt, Evan Mattiasen, Arthur Sanders, Seth Riley, Jacob Kerby, Robert Fisher

Lee Kats

Aquatic amphibians are known to be vulnerable to a myriad of invasive predators. Invasive crayfish are thought to have eliminated native populations of amphibians in some streams in the semi-arid Santa Monica Mountains of southern California. Despite their toxic skin secretions that defend them from native predators, newts are vulnerable to crayfish attacks, and crayfish have been observed attacking adult newts, and eating newt egg masses and larvae. For 15 years, we have observed invasive crayfish and native California newts coexisting in one stream in the Santa Monica Mountains. During that period, we monitored the densities of both crayfish and …

Accounting For False Positive Detection Error Induced By Transient Individuals, Chris Sutherland, D Elston, X. Lambin

Chris Sutherland

Genetic Variation In Past And Current Landscapes: Conservation Implications Based On Six Endemic Florida Scrub Plants, Eric S. Menges, Rebecca W. Dolan, Robert Pickert, Rebecca Yahr, Doria R. Gordon

Rebecca W. Dolan

If genetic variation is often positively correlated with population sizes and the presence of nearby populations and suitable habitats, landscape proxies could inform conservation decisions without genetic analyses. For six Florida scrub endemic plants (Dicerandra frutescens, Eryngium cuneifolium, Hypericum cumulicola, Liatris ohlingerae, Nolina brittoniana, and Warea carteri), we relate two measures of genetic variation, expected heterozygosity and alleles per polymorphic locus (APL), to population size and landscape variables. Presettlement areas were estimated based on soil preferences and GIS soils maps. Four species showed no genetic patterns related to population or landscape factors. The other two species showed significant but inconsistent …

Conservation Implications Of Genetic Variation In Three Rare Species Endemic To Florida Rosemary Scrub, Rebecca W. Dolan, Rebecca Yahr, Eric S. Menges, Matthew Halfhill

Rebecca W. Dolan

Habitat conversion and fire suppression during the last 50 yr have greatly reduced and altered Florida scrub vegetation, resulting in threats to the persistence of its unique flora. As part of a larger conservation project, we investigated patterns of isozyme variation in three rare perennial scrub plants with overlapping ranges endemic to Florida rosemary scrub on the Lake Wales Ridge. All three species have low levels of genetic variation, comparable to or lower than those generally reported for rare plants with restricted geographic ranges. Liatris ohlingerae has more than twice the expected heterozygosity of the other two species, with little …

Conservation Implications Of Genetic Variation In Three Rare Species Endemic To Florida Rosemary Scrub, Rebecca W. Dolan, Rebecca Yahr, Eric S. Menges, Matthew Halfhill

Rebecca W. Dolan

Habitat conversion and fire suppression during the last 50 yr have greatly reduced and altered Florida scrub vegetation, resulting in threats to the persistence of its unique flora. As part of a larger conservation project, we investigated patterns of isozyme variation in three rare perennial scrub plants with overlapping ranges endemic to Florida rosemary scrub on the Lake Wales Ridge. All three species have low levels of genetic variation, comparable to or lower than those generally reported for rare plants with restricted geographic ranges. Liatris ohlingerae has more than twice the expected heterozygosity of the other two species, with little …

Responses Of Bats To Forest Fragmentation In The Mississippi River Alluvial Valley, Arkansas, Usa, Rex E. Medlin Jr., Matthew B. Connior, Karen F. Gaines, Thomas S. Risch

Karen F. Gaines

Intense conversion of bottomland hardwood forests to rice and soybeans in the Mississippi River Valley of Arkansas has restricted the remaining forest to isolated fragments. Habitat fragmentation has proven to be detrimental to population sustainability of several species, and is the subject of intense study with often species and latitude specific responses. We compared both coarse land area classes and landscape fragmentation metrics from six 30 km × 30 km subsets centered on publicly owned management areas to bat captures obtained from a 2005 population study. Patch density was the strongest predictor of total captures (R 2 = 0.801, p …

Foraging Ecology Of The Endangered Wood Stork Recorded In The Stable Isotope Signature Of Feathers, Christopher S. Romanek, Karen F. Gaines, A. L. Bryan Jr., I. L. Brisbin Jr.

Karen F. Gaines

Down feathers and regurgitant were collected from nestling wood storks (Mycteria americana) from two inland and two coastal breeding colonies in Georgia. The stable isotopic ratios of carbon ( 13 C/12 C) and nitrogen ( 15N/ 14N) in these materials were analyzed to gain insights into the natal origins of juvenile storks and the foraging activities of adults. Down feathers differed in δ 13 C between inland and coastal colonies, having average isotopic values that reflected the sources of carbon fixed in biomass at the base of the food web. Feathers from the inland colonies differed between colonies in δ …