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1	ROOSTING BEHAVIOR, HABITAT USE, AND RELATIVE ABUNDANCE OF THE NORTHERN LONG-EARED BAT (<em>MYOTIS SEPTENTRIONALIS</em>) FOLLOWING ARRIVAL OF WHITE-NOSE SYNDROME TO MAMMOTH CAVE NATIONAL PARK Thalken, Marissa M. 01 January 2017 (has links) White-Nose Syndrome (WNS; Pseudogymnoascus destructans) is responsible for the regional population collapse of many cave-hibernating bat species, including the northern long-eared bat (Myotis septentrionalis), in eastern United States and Canada. I evaluated roosting behavior, habitat selection, and landscape-scale distribution of roosts of the northern long-eared bat during spring emergence and the early maternity season in Mammoth Cave National Park, Kentucky, USA, from 2015 to 2016. Logistic regression analysis comparing habitat features of roosts with random plots indicated selection of roosts reflected the costs of energetic demands by sex and reproductive status. Relative abundance of local bat species was assessed pre- and post-arrival of WNS in the Park during the summer season, with capture rates observed during the progression of WNS indicating that the fungal disease led to declines in the overall abundance of several bat species on the summer landscape, especially the northern long-eared bat. Distributional trends were quantified using spatial point pattern analysis which indicated that bats had clear roosting patterns associated with landscape level features and habitat resources. Monitoring bat populations regionally and at local scales will be imperative to helping conservation efforts for several bat species most affected by WNS. bats habitat use Myotis septentrionalis roost selection species assemblage white-nose syndrome Forest Biology Forest Sciences
2	Freshwater Flow, Saltwater Intrusion, Paper Mill Effluent, and Fish Assemblage Structure in the Lower Neches River, Texas Pizano, Rebecca I 16 December 2013 (has links) In 2011, Texas experienced the worst drought in recorded history. This has escalated concerns regarding environmental flows needed to sustain freshwater and estuarine systems as human needs are addressed during drought periods. In this thesis, I analyze fish assemblages and water quality variables in order to observe the effects of drought in the lower Neches River below the saltwater barrier located upstream from Beaumont, Texas. Fish and water quality samples were taken during drought conditions during fall 2011 and summer 2012, after a season of rain. During fall 2011, sites surveyed above the barrier had lower salinity but similarly low dissolved oxygen (DO) levels compared with sites surveyed below the barrier. Salinity levels during fall 2011 were relatively high (reaching up to 15 ppt), whereas salinity during summer 2012 never rose above 1.5 ppt. For gillnet samples obtained during fall 2011, fish species richness was higher in December following a series of rain events than during drought conditions in October and November. Although fish species richness was similar between fall 2011 and summer 2012, species composition varied greatly. For seine samples obtained during summer 2012, species richness was higher during May and July (when the barrier was open) than during June and August (when the barrier was closed). Species richness was lowest for sites in closest proximity to a paper mill effluent discharge pipe located below the barrier. Also, species richness was higher at sites above the barrier than at sites below the barrier regardless of whether or not the barrier was closed. Multivariate statistical analyses of gillnet samples revealed a large amount of compositional overlap among fish assemblages, regardless of time period and location; however, analyses of seine samples revealed that fish assemblages above the barrier were different than those from samples obtained below the barrier and that fish assemblages varied based on time period. Results indicate that, during periods of low flow, water quality deteriorates in the Lower Neches River below the saltwater barrier. During these periods of environmental degradation, fish assemblages have reduced diversity and sensitive freshwater species decline in abundance, with some absent from survey samples. paper mill effluent saltwater intrusion drought freshwater inflow fish species assemblages species assemblage Neches River Texas
3	Video on the rocks : use of a video lander platform as a survey tool for a high-relief nearshore temperate rocky reef Easton, Ryan Reid 30 November 2012 (has links) The nearshore waters off the Oregon coast (< 73 meters) are a region of high productivity and economic value, with a variety of habitats that include rock outcrops. Temperate reef habitats are important to many commercially important fishes inhabiting the Pacific coast, including canary rockfish (Sebastes pinniger) and yelloweye rockfish (Sebastes ruberrimus), which are currently listed as "overfished" by the Pacific Fishery Management Council. Along the Pacific coast of North America, nearshore rocky reefs have been designated as essential fish habitat (EFH), while comprising approximately just seven percent of Oregon's territorial sea. Despite this EFH designation, the use of visual (SCUBA, remotely operated vehicles (ROVs), human occupied vehicles (HOVs)) and non-visual (bottom trawl) survey methods within this region has been infrequent and scattered, providing limited information on species-habitat associations and species assemblages within nearshore waters. It is logistically difficult and costly to survey nearshore reefs. The factors that have led to the paucity of surveys include the depth (too deep for SCUBA surveys but too shallow for larger survey vessels), high seas limiting available days for field work, and the high-relief nature of the habitat (precluding the use of bottom trawls). In an effort to better understand species-habitat associations and community structure of Oregon's nearshore reefs, an autonomous underwater drop-camera termed the "video lander" was employed at the Three Arch Rocks reef, a nearshore reef off of Oceanside, Oregon. Video lander footage was used to identify and groundtruth habitat types, as well as species assemblages over two distinct seasons: spring/summer (n=272) and winter (n=108). Many species-habitat associations were statistically significant: yelloweye rockfish (large boulder p<0.0073), canary rockfish (small boulder p<0.0006), kelp greenling (Hexagrammos decagrammus) (bedrock outcrop p<0.0162), and quillback rockfish (Sebastes maliger) (large boulder p<0.0016). Summer and winter surveys revealed similar habitat associations and distributions for these species. I found no significant difference in species composition between the northern and southern regions of the reef (Bray-Curtis dissimilarity index (BCDI) = 71.71, ANOSIM p>0.1447), but a significant difference between spring/summer and winter seasons was identified on the outer section of the reef, due to the presence of spotted ratfish (Hydrolagus colliei) in the winter (BCDI =76.41, ANOSIM p < 0.0155). My study shows that data provided by the video lander can fill existing gaps in our understanding of nearshore distribution and habitat associations of temperate rocky-reef fishes off the Oregon coast. / Graduation date: 2013 Rockfish Habitat associations Oregon Species assemblage
4	The Larger Pelagic Crustacea of the Gully Submarine Canyon MacIsaac, Kevin Gregory 22 August 2011 (has links) The larger pelagic crustacean fauna of the Gully submarine canyon is described for the first time, based on three annual summer surveys. The larger Crustacea are a significant part of the Gully fauna, and are dominated by cold temperate species, in particular the northern krill Meganyctiphanes norvegica and the decapod Sergestes arcticus. In all, at least 69 species were collected from the surface to bathypelagic depths, with seventeen being new Canadian records. With the exception of M. norvegica, inter-annual variation in the dominant species was minor. The species assemblage varied primarily with depth surveyed and diel cycle, and not year. Comparing the larger pelagic crustaceans in the Gully and over the adjacent continental slope showed that overall species number, biomass, and abundance were all greater in the canyon, the biomass of S. arcticus particularly showing a positive “Gully effect”.
5	Determinants of population structure in the world's smallest primate, <i>Microcebus berthae</i>, across its global range in Menabe Central, Western Madagascar / Determinanten der räumlichen Populationsstruktur des kleinsten bekannten Primaten, <i>Microcebus berthae</i>, in dessen globalem Verbreitungsgebiet Menabe Central, West-Madagaskar Schäffler, Livia 16 December 2011 (has links) No description available. 570 Biowissenschaften Biologie räumliche Verteilung ökologische Struktur Populationsdynamik Koexistenz Gemeinschaft nahverwandte Arten interspezifische Interaktion Konkurrenz Prädation Mausmaki Artenschutz Biodiversität distribution ecological structure population dynamics species assemblage congener coexistence interspecific interaction competition predation <i>Microcebus</i> biodiversity conservation 42.65 Tiergeographie Tierökologie 42.84 Mammalia Primatenkunde 43.31 Naturschutz Artenschutz 43.70 Entwicklungsländer und Umwelt Artenschutz WXR 000 Tierökologie WXU 000 Populationsdynamik Tiergeographie WXU 100 Faunen

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