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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Habitat Use of Six Skinks in Southern Taiwan

Zhu, Houng-Da 10 September 2002 (has links)
This study was conducted at Shuang-Yuan bridge (the border between Kaoshiung County and Ping-Tung County) and another four areas of Tai-Wu region at Ping-Tung County from June to August, 2000 and January to December, 2001. The main purpose of this research was to investigat the habitat use among sympatric skinks. During the research period, I discovered six species of skinks, including Eumeces elegans, Mabuya longicaudata, M. multifasciata, Scincella formosensis, Sphenomorphus incognitus and S. indicus. At Shuang-Yuan bridge, the habitat use among Mabuya longicaudata and Mabuya multifasciata differed significantly. Mabuya multifasciata was most common in open area, but Mabuya longicaudata was found mostly in close area, based on their habitat preference. Sphenomorphus incognitus and Sphenomorphus indicus were found in sympatry in low altitude area and their habitat use were similar, but in higher altitude region the habitat use differed considerably among two species, Sphenomorphus incognitus was more common in open area. Eumeces elegans was rare at three lower altitude regions in Tai-Wu, but more common at higher region and the habitat use was significantly different to that of Sphenomorphus indicus. Sphenomorphus indicus was found mainly in the ditch and water pipe, while Eumeces elegans was strongly associated with grass and rocks. Scincella formosensis was rare relatively among six skinks and preferred grass and leaf-litter.
2

Habitat use by northwestern gartersnakes (Thamnophis ordinoides) in Saanich, British Columbia

Dixon-MacCallum, Graham 13 December 2013 (has links)
Understanding habitat requirements of species is fundamental for their conservation. Comparing habitat variables measured at locations where animals are found to random locations is one method of understanding how a species uses its habitat non-randomly. Northwestern gartersnakes (Thamnophis ordinoides) are common in parks in Victoria, but their specific habitat requirements are poorly understood. Victoria’s parks vary in habitat composition from mature Douglas-fir forest to Garry Oak meadow, with open grassy areas, to parking lots and patches of dense invasive shrubs. Based on previous studies and thermoregulatory needs of snakes, I predicted that substrate temperature and distance to edge would be of greatest importance in determining where snakes would be found. From May to September, 2012 I captured 124 northwestern gartersnakes by hand on random transects and habitat edge surveys. At capture locations and randomly chosen points nearby I measured the composition and structure of vegetation, as well as abiotic factors such as substrate temperature, aspect and slope. Also, I used air photos and GIS to determine proportional use of broad habitat types at home range scale. I found differential use of habitat between the sexes in relation to the proportion of herbaceous vegetation and organic litter. Northwestern gartersnakes generally use locations that are warmer than random locations, though individuals that have fed recently have a greater thermophilic response than snakes that have not. Overall, at small scale, distance to edge was the most important variable measured. At large scale, estimated home ranges contained more open ground as northwestern gartersnake snout-vent-length (SVL) increased (presumably because they had fewer potential predators and could more afford to use open habitats). These results support my hypothesis that warm locations that are close to habitat edges are important habitat for northwestern gartersnakes. The parks at which I conducted surveys appear to have large populations of northwestern gartersnakes with abundant habitat. However, the fact that habitat is used does not necessarily indicate that it is of high quality, and further research is required to determine if these populations are stable, increasing, or decreasing. / Graduate / 0329 / grahamdm@uvic.ca
3

Žvirblinės pelėdos (Glaucidium passerinum L.) buveinių pasirinkimas ir vokalizacijos sąlygos / Habitat use and vocalization conditions in the eurasian pygmy owl (glaucidium passerinum l.)

Grašytė, Gintarė 04 July 2014 (has links)
Žvirblinė pelėda yra plačiai paplitusi, tačiau visame areale saugoma rūšis. ES šalyse šios rūšies apsaugai steigiamos specialios saugomos teritorijos, kuriose pagal Paukščių direktyvą vykdomas rūšies monitoringas. Tačiau iki šiol nėra kiekybiškai analizuotos žvirblinės pelėdos buveinės bei nežinoma, kokiomis sąlygomis ši pelėda dažniausiai vokalizuoja. Todėl šio tyrimo tikslas buvo išanalizuoti žvirblinės pelėdos buveinių pasirinkimą ir vokalizacijos sąlygas. Žvirblinės pelėdos makrobuveinės (200 ha kvadratai, kuriuose 2005-2011 m. buvo fiksuotos žvirblinės pelėdos) darbo metu buvo palygintos su atsitiktinai parinktomis teritorijomis. Nustatyta, kad žvirblinė pelėda teikia pirmenybę didesniam miško plotui makrobuveinėje (82 % ± 18 % SD, n = 178), taip pat eglynams (21 % ± 14 % SD, n = 160) ir brandiems miškams (33 % ± 14 % SD, n = 160), tačiau vengia minkštųjų lapuočių (baltalksnių, tuopų ir gluosnių) medynų (2 % ± 4 % SD, n = 160). Žvirblinės pelėdos buveinių pasirinkimas skyrėsi skirtinguose Lietuvos subregionuose. Nerasta nė vieno kintamojo, kuris būtų svarbus visuose subregionuose. Natūrali žvirblinės pelėdos vokalizacija buvo registruojama 2001-2011 metais, žiemos – pavasario ir rudens – žiemos sezonais. Vokalizacijos datos skirtingais metais skyrėsi, tačiau vidutinė vokalizacijos data žiemos – pavasario sezonu buvo kovo 20 d. (n = 117), rudens – žiemos sezonu – spalio 12 d. (n = 42). Nustatyta, kad pagrindiniai pelėdos vokalizacijai įtaką darantys veiksniai yra... [toliau žr. visą tekstą] / The Eurasian Pygmy Owl (Glaucidium passerinum L.) is a widely distributed and protected species all over its distribution range. There are special protected areas in EU countries, where species’ monitoring is carried out under EU Birds directive. However, there is a lack in quantitative data on species macrohabitat, habitat preferences, and vocalization conditions. This thesis addresses these issues. The Eurasian Pygmy Owl macrohabitats – squares of 200 ha, where territorial owls were located in 2005 - 2011 – were compared with randomly selected 200 ha squares. It was ascertained that the Pygmy Owl prefers forest (82 % ± 18 % SD, n = 178) with spruce (21 % ± 14 % SD, n = 160) and mature stands (33 % ± 14 % SD, n = 160) in its macrohabitats. It avoids deciduous trees like the Grey Alder, poplar and willow (2 % ± 4 % SD, n = 160). On the other hand, the Eurasian Pygmy Owl inhabits various types of forests in distinct sub-regions of Lithuania. There was no single variable, which was more important than others for the species habitat use in three analysed sub-regions, however, different preferred/avoided variables emerged. Natural Eurasian Pygmy Owl vocalization was registered 2001 - 2011, during two seasons per year. The date of vocalization varied between years, however, the average date of owl vocalization was 20th of March in winter - spring season (n = 117) and 12th of October in autumn - winter season (n = 42). It was found, that the key factors affecting the Eurasian Pygmy... [to full text]
4

Regional variation in tiger shark (Galeocerdo cuvier) abundance and habitat use

Cameron, Kathryn 15 July 2010 (has links)
The purpose of this study was to investigate whether there is regional variation in the abundance and habitat use of tiger sharks (Galeocerdo cuvier) within in a model seagrass ecosystem. Abundance was determined with catch rates on drumlines and habitat preferences were investigated using acoustic tracking of large tiger sharks (n=4). I found spatiotemporal variation in the probability of catching at least one shark and in catch rates on days sharks were caught. In general, sharks were present throughout more of the year and in higher abundances in the northern region. Habitat use also varied between regions. In the northern region, sharks moved randomly with respect to habitat, while in the southern region sharks preferred shallow habitats. Although preliminary, these results suggest that large predator abundance and habitat use may vary over relatively small spatial scales and that such variation may be useful for elucidating their ecological role.
5

Terrestrial Habitat Use by Radio-Implanted Spotted Salamanders (Ambystoma maculatum)

Nussbaum, Ashley Lynn January 2005 (has links)
No description available.
6

Temporal variation and inter-relationship of movement and resource selection of red deer (Cervus elaphus) with respect to climate: a case study

Hu, Qinglin January 2006 (has links)
Red deer (Cervus elaphus) is one of at least 31 herbivorous exotic mammals existing in New Zealand. All of these species have the potential to affect environmentral and production values. Reducing their impacts on their values, strengthening effective managements are important issues to a variety of agencies within New Zealand including the Department of Conservation (DOC), Ministry of Agriculture and Forestry (MAF), local and regional governments. This research studied animal movement pattern and habitat use of 2 GPScollared red deer in the Canterbury high country and found (1) deer movement was affected by climatic variables such as rainfall and temperature, which had positive or negative effect on it, and had seasonal variation; (2) deer had dominant landcover use categories, depending on climate, season, and individual characteristics (3) deer had different movement patterns in terms of hourly distances. The purpose of the study is to draw accurate inferences from spatially explicit data for biosecurity managers and policy-makers through: (1) using global positioning system (GPS) as a tool to elucidate the application of GPS on red deer in wildlife management; (2) Animal Movement Analysis Arc View® 3.2 Extension under Arc View® Geographic Information System (GIS); (3) Animal movement analysis which used Generalized Additive Models (GAMs) to show how the movement of red deer was affected by different periods of time, seasons months and climatic variables (for example, rainfall and temperature).
7

The ecology of the side-striped jackal (Canis adustus Sundevall), a vector of rabies in Zimbabwe

Atkinson, Robert Peter Douglas January 1997 (has links)
No description available.
8

Thermoregulatory behavior and habitat use of Liolaemus aparicioi at two different altitudes

Gustafsson, Jannie Frida Linn January 2015 (has links)
The thermoregulation of lizards depends highly on the environment they inhabit. Thermoregulation is crucial for physiological processes and affects therefore the life history of the lizard. High altitudes are characterized by a colder climate than on lower altitudes, and these environmental factors affects the thermoregulation of lizards. Lizards can however adapt to colder climates by adjusting their physiology and/or behavior. In this study two populations of Liolaemus aparicioi, an endemic lizard inhabiting the valleys close to La Paz, were observed at two different altitudes to investigate any differences in behavior or habitat use that could compensate for the high altitude. The behavioral displays associated to thermoregulation and the use of habitat were recorded in order to assess how they allocated their time and how they used the habitat available. The mean values of most parameters measured indicated that the population on the high altitude do compensate for the high altitude by behavior and habitat use.
9

The ecology of roe deer (Capreolus capreolus L.) inhabiting farmland in north-east Scotland

Haji Idris, Azarae bin January 1990 (has links)
A field study was carried out from April 1987 to May 1989 to investigate the ecology of roe deer (Capreolus capreolus L.) living in low-lying farmland in north-east Scotland. The study was conducted on unmarked and marked (mostly radio-collared) animals. The use of available habitats was investigated. The use of crop fields changes with seasons in the same year and in different years according to availability. Fields adjacent to woodlands were heavily used and preferred to fields farther from the woods. Most radio-collared deer used thicket woods during daytime and their use of other habitats varies according to availability in each home range. Aspects of movements and home range were studied. The daily home range size of each radio-collared deer varies from day to day. Seasonal and total home range sizes were generally larger than those found in other studies of roe deer in Britain. The largest seasonal range was observed in winter and the smallest in summer. Nine marked young deer dispersed from their established range from mid to the end of May. Group composition and group size changes seasonally. Members of adjacent groups associate and share common ground but members of distant groups do not. Twenty-nine of 37 woodlands surveyed in the extensive study area were occupied by roe deer. Analysis suggests that deer occupied large woodlands of mixed structural stages with clearings.
10

Thermoregulating behavior and habitat use of Liolaemus aparicioi

Gustafsson, Jennie Frida Linn January 2015 (has links)
The thermoregulation of lizards depends highly on the environment they inhabit. Thermoregulation is crucial for physiological processes and affects therefore the life history of the lizard. High altitudes are characterized by a colder climate than on lower altitudes, and these environmental factors affects the thermoregulation of lizards. Lizards can however adapt to colder climates by adjusting their physiology and/or behavior. In this study two populations of Liolaemus aparicioi, an endemic lizard inhabiting the valleys close to La Paz, were observed at two different altitudes to investigate any differences in behavior or habitat use that could compensate for the high altitude. The behavioral displays associated to thermoregulation and the use of habitat were recorded in order to assess how they allocated their time and how they used the habitat available. The mean values of most parameters measured indicated that the population on the high altitude do compensate for the high altitude by behavior and habitat use.

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