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Hoover M.,University of Connecticut | Civco D.,University of Connecticut | Whelchel A.,Conservation Programs
American Society for Photogrammetry and Remote Sensing Annual Conference 2010: Opportunities for Emerging Geospatial Technologies | Year: 2010

Given their location in the intertidal zone, coastal salt marshes will be one of the ecosystems first affected by sea level rise. As sea level rise increases, marshes will begin to migrate inland if surrounding topography and land use provide suitable habitat. The question remains whether or not this migration inland will provide enough new habitat to sustain current marsh area as the seaward edge of the marsh begins to become permanently inundated. This project created an ArcGIS tool using Python computer language that projects future salt marsh habitat under a variety of sea level rise and land use scenarios. The tool has several inputs including vegetation classifications, Digital Elevation Models (DEMs), current tidal conditions, and accretion rates. An object-oriented approach to image classification was used to develop the vegetation classifications and the DEMs were developed from LiDAR point clouds using the Geostastical Analyst in ArcGIS. This research expands on a presentation given at ASPRS 2009 in Baltimore, MD which used a preliminary version of the marsh migration tool to project future marsh habitat in eight study sites on the Connecticut coastline. This research has finished the development of the tool, making it more user-friendly and is currently expanding the geographic extent to include most of Long Island Sound. Source

The population of the Arabian Gazelle (Gazella arabica) was assessed on Farasan Kebir, the main island of the Farasan Archipelago (Saudi Arabia), from June 2010 to January 2013, using road strip counts. Two methods of estimating the population size were applied to analyse data obtained from the road strip count: (i) the traditional technique after Bothma, with a fixed strip width, and (ii) distance sampling using DISTANCE 6.0. Estimates varied between 483 gazelles (95% CI: 44) in November 2010 and 1070 gazelles (95% CI: 63) in June 2010. The number of gazelles estimated for Farasan Kebir using distance sampling is 2388 gazelles (95% CI: 921) in December 2011, 1199 gazelles (95% CI: 1372) in June 2012, and 1048 gazelles (95% CI:1524) in January 2013. Taking into account previous counts (1988-2009) the population seems, despite considerable variations, surprisingly stable. This may be attributed to a prevailing fishing culture among local residents and thus the absence of traditional hunting as well as the ranger activities on the islands. The disparity between the two estimation methods decreased to only 270 gazelles in January 2013 and provides additional confidence in the future application of both estimation techniques.The traditional technique is recommended as the more practical method for rangers and conservation mangers to determine population changes. ©2013 Taylor & Francis. Source

Wronski T.,Conservation Programs | Wronski T.,King Khalid Wildlife Research Center | Plath M.,Goethe University Frankfurt | Ziege M.,Goethe University Frankfurt
Journal of Ethology | Year: 2013

Mammalian scent marking in localized defecation sites (latrines) has often been interpreted in the context of (male) territory defense. However, latrines could have different functions in males and females, especially where territorial males monopolize groups of females with stable social alliances and pronounced home range overlap. We investigated the communicatory significance of latrines in wild Arabian gazelles (Gazella arabica) and assessed the spatial distribution of latrines within home ranges. Latrine density and utilization was highest in the center of female group home ranges, and less frequent in peripheral home range sections, pointing towards communication within groups rather than towards territoriality. When considering male home ranges, latrine densities and utilization were higher in non-overlap zones, contradicting a territorial function. This pattern appears to be caused by more females than territorial males per given area establishing latrines. A subsequent survey of latrine utilization, based on camera trapping, suggests that males use latrines for territory defense: males visited latrines in overlap zones disproportionally more often than females, and successions of two males prevailed. Our study thus highlights that male territorial marking can be masked when males and females use the same marking system for different purposes. © 2012 Japan Ethological Society and Springer Japan. Source

Schulz E.,University of Hamburg | Fraas S.,University of Hamburg | Kaiser T.M.,University of Hamburg | Cunningham P.L.,Conservation Programs | And 5 more authors.
Mammalian Biology | Year: 2013

Food preferences of the sand gazelle (Gazella marica) from the Mahazat as-Sayd Protected Area in Saudi Arabia were evaluated using focal animal sampling in conjunction with an eco-morphological method examining two parameters of tooth wear, i.e., occlusal relief and cusp shape. Observations of live, free-ranging animals (n= 53) showed that sand gazelles generally consumed more grass (58.4%) than browse (41.6%). However, during the dry season, gazelles spent significantly more time browsing (51.0%) and less time grazing (49.0%) than under wet conditions (browsing: 17.6%; grazing: 82.4%). Thus, consistent with predictions, sand gazelles are intermediate feeders but shift towards browsing when grass is scarce. The mesowear signature of the sand gazelle is consistent with a grazing signal in other ruminants. In other words, the browse component of the diets of live animals was not reflected in the tooth wear. This could have occurred because browse is less abrasive than grass, but more likely because all food types are heavily abrasive in this dusty habitat. We conclude that the sand gazelle population in Mahazat as-Sayd encounters a highly abrasive diet, which has implications for their ability to meet nutritional demands. © 2012 Gesellschaft für Säugetierkunde. Source

Lonsdorf E.,Franklin And Marshall College | Travis D.,Conservation Programs | Travis D.,University of Minnesota | Ssuna R.,Ngamba Island Chimpanzee Sanctuary | And 14 more authors.
Primates | Year: 2014

Infectious diseases are widely presumed to be one of the greatest threats to ape conservation in the wild. Human diseases are of particular concern, and the costs and benefits of human presence in protected areas with apes are regularly debated. While numerous syndromes with fatal outcomes have recently been described, precise identification of pathogens remains difficult. These diagnostic difficulties are compounded by the fact that direct veterinary intervention on wild apes is quite rare. Here we present the unique case of a wild chimpanzee at Gombe National Park that was observed with a severe illness and was subsequently examined and treated in the field. Multiple specimens were collected and tested with the aim of identifying the pathogen responsible for the illness. Our findings represent the first extensive screening of a living wild chimpanzee, yet despite our efforts, the cause and source of illness remain unknown. Nevertheless, our findings represent valuable baseline data for the ape conservation community and for comparison with other recent findings. In addition, we present the case here to demonstrate the planning required and multiple types of expertise necessary to maximize the amount of data obtained from such a rare intervention, and to provide lessons learned for future studies. © 2013 Japan Monkey Centre and Springer Japan. Source

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