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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.
11

Correlation of the feeding habits, jaw musculature and type of teeth of some South African golden moles

Thelejane, Thomas Sohl January 1958 (has links)
The jaw musculature and its innervation in the Chrysochloridae studied is typicaly mammalian except that the m. temporalis occupies the whole of the orbito-temporal fossa. The antemolar teeth are specialized, while the molars are simple and primitive. Normally the diet of Golden Moles consists of earthworms, insects in all stages of development and millipedes. The firm implantation of the antemolar teeth can be correlated with their function of catching the prey, while the molars are adapted for a worm-like diet. The available evidence indicates that the genera Bematiscus and Chrysospalax are more primitive than the other Golden Moles. Since Golden Moles feed on insects in all stares of development and millipedes, they can be considered as being of economic importance.
12

Can MODIS NDVI measurements be used to predict zebra (Equus burchelli) foraging patterns?

Zinn, Andrew David. 03 March 2014 (has links)
As an indicator of above ground net primary productivity, the Normalised Difference Vegetation Index (NDVI) has been identified as important tool in understanding the resource requirements and distribution patterns of large herbivores. The efficacy of NDVI as an ecological tool is however, strongly contingent upon the scale of the foraging hierarchy at which data are interpreted. In this study I investigated whether vegetation greenness, as represented by MODIS NDVI 250 m resolution imagery, is a driver of zebra (Equus quagga) foraging patterns at three spatial/temporal scales, namely location within sixteen day home ranges, sixteen day home range within seasonal home range and seasonal home range within total home range, during both wet and dry periods. I also investigated how tree canopy cover influences the ability of MODIS NDVI to see the greenness at which zebra respond. During the wet season, the zebra clearly demonstrated evidence of selecting for greenness and a tendency to avoid areas of high woody canopy at all three scales. Conversely, during the dry season the zebra showed no preference for greenness and no consistent preference for or against woody cover across the three scales. I also noted that despite a positive relationship between ΔNDVI and woody canopy cover, the relationship is not significant and suggests that in savanna ecosystems tree densities may not be high enough to affect overall MODIS NDVI readings. These results indicate that zebra foraging behaviour is complex and differs according to the scale of analysis, season, and even between individual zebra herds. The ability of MODIS NDVI to elucidate zebra movements is therefore limited to specific spatial and temporal scales and should be accompanied by an understanding of non-forage related factors.
13

Central place foraging : quantitative tests of a patch use model in the eastern chipmunk (Tamias striatus)

Giraldeau, Luc-Alain. January 1980 (has links)
No description available.
14

Temporal and spatial scales in foraging ecology: Testing hypotheses with spiders and squirrels.

Smallwood, Peter Diehl. January 1992 (has links)
Animal foraging behavior is shaped by patterns and processes that operate on several temporal and spatial scales. In chapter 1, I briefly review the meaning and importance of temporal and spatial scales. In chapter 2, I examine the foraging behavior of the Long Jawed spider (Tetragnatha elongata). In North Carolina, the spider exhibits the counter intuitive behavior of relocating its web daily in rich habitats, but rebuilding its web on the same site for many days in a row in poor habitats. I test a risk-sensitive foraging model of this behavior, but its predictions were not met. I develop an alternative hypothesis to explain the behavior of Long Jawed spiders: that the higher density of spiders in rich habitats results in more frequent interactions between spiders, and that these interactions provoke spiders to relocate more often in rich habitats. I report the results of density-reduction experiments, which corroborate my hypothesis. In chapter 3, I examine the foraging and storing strategy of the Eastern Gray Squirrel (Sciurus carolinensis). The squirrels ate most of the white oak (WO) acorns, and buried most of the red oak (RO) acorns, confirming my prediction. I also present the results of an experiment designed to reveal whether squirrels used tannin and/or fat content of acorns to distinguish between acorns of different species. The results of this experiment were inconclusive. In another experiment, I buried a large number of acorns, and assessed samples of acorns retrieved at intervals through the fall/winter season. I found that tannin levels in RO acorns did not decline during their interment, rendering an alternative hypothesis untenable. Further, I confirmed an earlier assumption: stored WO acorns do suffer more insect damage than RO acorns. I hypothesize that the storing and foraging strategy of squirrels may affect the distribution of oaks, and review evidence from the literature that supports this hypothesis. Finally, I argue that Clark's Nutcracker (Columbiana nucifraga) may employ the same strategy as it forages for pine seeds, and again review evidence from the literature to support this hypothesis. (Abstract shortened by UMI.)
15

Prey caching in the hunting strategy of small predators

Oksanen, Tarja Maarit January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
16

Hoarding by the wood rat, Neotoma albigula, and the kangaroo rat, Dipodomys merriami: a preliminary investigation

Tuntland, Patricia Jane, 1943- January 1969 (has links)
No description available.
17

Effects of adaptive foragers on the diversity and functioning of assembled model communities /

Tarantino, William J., January 2008 (has links) (PDF)
Thesis (M.Sc.)--College of William and Mary. / Vita. Includes bibliographical references. Also available via the World Wide Web.
18

The effect of locus of conditioning on the taste potentiation of non-gustatory food cues

Kluge, Silvia von 01 January 1986 (has links)
No description available.
19

The feeding ecology and habitat use of the aardvark (Orycteropus afer)

Lindsey, Peter Andrew 16 November 2006 (has links)
The seasonal diet, feeding patterns, feeding selection and habitat selectivity of the aardvark were determined during summer and winter at Tussen die Riviere Nature Reserve in the southern Free State. Pitfall trapping, dig sampling and quadrat sampling were used to determine the resource base of three habitats in the summer and winter of 1998. A total of 44 ant species of 5 sub families and 17 genera, and two termite species of two sub families were recorded. Pitfall trapping was the most successful technique, followed by quadrat sampling (51.1%) and finally, dig sampling (48.8%). Abundance and diversity was higher during summer than winter. Monomorium albopilosum was the most abundant species in all habitats in winter, whilst Anoplolepis custodiens was the most abundant in summer. The grassland habitat yielded the highest abundance and diversity, followed by the steep slope and riverine areas. Seasonal diet and foraging patterns were determined through faecal analysis and observation of four habituated aardvarks. The Formicidae were more important than the Isoptera in both seasons. The feeding of the aardvark was highly selective, only 28.8% of the available species having been utilised. Prey selection was found to be most highly correlated with prey size, prey abundance, prey mobility, and prey calorific value. Aardvarks were highly selective in their habitat utilisation. The vast majority of feeds were made in the grassland areas where prey abundance was greatest, compared to negligible numbers of prey in the rocky steep slopes and no prey in the riverine areas due to periodic flooding. / Dissertation (MSc (Veterinary Tropical Diseases)--University of Pretoria, 1999. / Veterinary Tropical Diseases / unrestricted
20

The Nutritional Ecology of Adult Female Blue Monkeys, Cercopithecus mitis, in the Kakamega Forest, Kenya

Takahashi, Maressa January 2018 (has links)
The search for food and adequate nutrition determines much of an animal's behavior, as it must ingest the macronutrients, micronutrients, and water needed for growth, reproduction and body maintenance. These macro- and micronutrients are found in varying proportions and concentrations in different foods. A generalist consumer, such as many primates, faces the challenge of choosing the right combination of foods that confers adequate and balanced nutrition. Diet selection is further complicated and constrained by antifeedants, as well as digestive morphology and physiological limitations. Nutritional ecology is the study of the connected relationships between an organism, its nutrient needs (determined by physiological state), its diet selection, and the foraging behavior it uses within a specific food environment. Additionally, these relationships are complex and changeable since the nutrient needs of a consumer change over time and food resources (including the nutritional composition) vary spatiotemporally. Published data on primate nutritional ecology are limited, with most investigations of nutritional needs stemming from captive populations and few field studies. To contribute to the body of knowledge of nutritional ecology in natural populations, I examined the nutritional ecology of wild adult female blue monkeys, Cercopithecus mitis. I used the geometric framework (GF) to quantify nutritional patterns, as it allows simultaneous examination of multiple nutrients that may be driving foraging behavior and patterns of food intake. Blue monkeys are known to be generalist feeders, with flexible feeding behavior. The population I studied inhabits the Kakamega Forest, western Kenya. This forest has a history of variable human modification on a small scale, and offered a unique opportunity to examine environmental factors (e.g. degree of human-modification of forest type, food availability), social factors (dominance rank), and physiological factors (reproductive demand) that may alter blue monkey nutritional strategies. From January and September 2015, a team of field assistants and I collected behavioral data from 3 study groups, intensively sampling 24 adult females that varied in dominance rank and reproductive condition. I used all-day focal follows to quantify feeding behavior, which allowed me to assess diet selection and nutrient intake on a daily basis. I also monitored subjects' daily movement. To assess food availability, I quantified vegetative differences among major habitat types within each group's home range and monitored biweekly changes in plant production of fruits and young leaves, which were major constituents of the plant-based diet. I collected >300 food samples, as well as fecal samples, and analyzed them for macro-nutritional content using wet chemistry and near-infrared spectroscopy techniques. I combined data to examine patterns in diet and nutritional strategy on different scales: patterns across subjects, between groups and within the population as a whole, patterns in the diet on the food composition level versus nutrient intake level, and patterns in nutrient intake on a daily basis versus a long term basis (i.e. over the course of the study period). Additionally, I evaluated factors that might affect variation in nutritional strategies, including a female's reproductive condition, dominance rank, habitat use, and degree of frugivory or folivory in daily intake, as well as food availability in the environment. Kakamega blue monkeys ate a broad diet of over 445 food items (species-specific plant parts and insect morphotypes). Fruit was preferred food, and particular species-specific fruits constituted the majority of important food items (i.e., those contributing >1% of total caloric intake by group); many fruits were highly selected (i.e. eaten more than expected based on availability). Many species-specific young leaves also were important food items, though they were eaten in proportion to their availability, or even less often. Regardless of whether group diet was characterized by time spent feeding or by calories, fruit remained the largest constituent and young leaves the second largest. A subject's daily path length was negatively related to proportion of fruit in the diet (by kcal) because females focused feeding in particular trees when important fruits ripened and thus traveled less. Daily path length was not related to group size, probably because females spread out when foraging to avoid within-group scramble competition over food. Group differences in the food composition of diets likely reflected habitat differences in food distribution. Comparison of the population's diet to data from previous studies showed that as study groups moved into new areas and habitats, they capitalized on new food resources, reinforcing the idea that blue monkey are flexible feeders. During this study, subjects adjusted their diet in response to food availability in the environment, consuming more fruit (by percentage of diet and absolute kcal) when fruit was more available. In contrast, subjects ate fewer young leaves (by absolute kcal) when either fruit or young leaves were more available, suggesting that young leaves served as fallback food. At the level of nutrient intake, it was also true that females consumed significantly more structural carbohydrates when fruit availability was low. Despite their diverse diets and changes related to food availability, females actively regulated food intake to converge daily on a similar nutrient intake (grand mean of 637 kcal, with 108 kcal from protein, 149 kcal from lipid, 88 kcal from structural carbohydrates, and 293 kcal from non-structural carbohydrates, N=24). Thus, considering a multidimensional nutritional niche, I characterized their feeding behavior at two levels: they were both food composition generalists and nutrient intake specialists. Blue monkeys showed a nutritional strategy on two different temporal scales: 1) daily protein prioritization and 2) long term non-protein energy (NPE; i.e. lipid + carbohydrate energy) to available protein (P) balancing. On a daily basis, protein intake (by kcal) showed the least amount of variation (by coefficient of variation) and subjects consumed similar amounts of protein, regardless of potential influences from environmental, social or physiological factors. Females allowed more variation in daily ratio of non-protein energy to protein (NPE:P), taking advantage of high NPE foods like fruit. They allowed higher NPE:P ratios when fruit was a larger proportion of their diet and when they spent less time in near-natural forest. There was no evidence that reproductive demand or dominance rank affected protein intake or NPE:P balance. Dominance rank also did not predict deviation (absolute or directional) from mean protein intake or mean NPE:P ratio. On a long term basis (i.e. over the 8 months of data collection), all subjects tightly balanced cumulative NPE:P intake, regardless of dominance rank. This long-term pattern in all 24 subjects suggests that it a species-typical strategy. However, lower ranking females ate more unique food items per day than higher ranking females. Varying daily dietary breadth may allow females to cope with social constraints while feeding, such that dominance rank had no effect on nutritional strategies. Further, the prevalence of NPE:P balancing in most nutritional ecology studies of primates suggests that the diversity of feeding strategies within this order of mammals may have evolved to allow them to adhere to that particular nutrient balance, though the rule of compromise (e.g. protein versus NPE prioritization) and the exact ratio balanced may differ by population or species. Blue monkeys regularly used human-modified habitats and ate considerable amounts of the non-natural foods found there (and elsewhere in the forest). Non-natural foods were directly derived from humans or human activity (e.g. via scavenging from trash) and exotic (non-native) plants, generally introduced inadvertently or for silviculture. Subjects incorporated a substantial amount of non-natural foods into their diets, with approximately a third of their daily calories derived from non-natural foods. Subjects in the group with the most access to human-modified habitat used non-natural foods the most extensively. Further, subjects in two groups showed clear preference for human-modified habitat while members of the third group used habitat types in proportion to their occurrence in the home range. Human-modified habitat, and the non-natural foods found within, may have been readily used because many non-natural foods provided similar access to nutritional space as natural foods. Some non-natural foods, like oil palm fruit and ugali (cooked maize flour), represented energetically dense food resources, which also proved attractive. Regardless of whether subjects fed primarily on natural or non-natural foods, they consumed similar amounts of daily protein. This prioritization of protein, coupled with the fact that females had higher NPE:P ratios when feeding mostly on non-natural foods, indicated that blue monkeys capitalized on non-natural resources to increase NPE intake as long as they were able to consume a threshold amount of protein. What remains unclear though, is whether there are adaptive advantages associated with the ability to consume diets of variable NPE:P ratios. Overall, blue monkeys in Kakamega Forest are very flexible feeders, perhaps to a greater degree than previously acknowledged. Subjects were able to consume a diverse diet of hundreds of species-specific food items, to shift their diet in response to changes in food availability, to capitalize on food resources found in different habitat types, to take advantage of non-natural food resources, and to tolerate a wide range of NPE:P ratios in daily diets. Further, on a nutritional level, they successfully navigated potential stressors from the physiological demands of reproduction and dominance rank to adhere to a particular nutritional strategy. Flexible behavior, such as spreading out during feeding or varying dietary breadth, indicates how blue monkeys may use particular feeding strategies to arrive at a common nutrient intake target. Despite daily fluctuations in NPE:P ratio that varied with environmental and dietary factors, all subjects were able to consume a consistent daily amount of protein and prioritized its intake above all other nutritional components. Finally, their tight adherence to long term NPE:P balancing suggested that they followed a nutritional strategy that operated on both daily and longer timescales. Primates are increasingly threatened from habitat loss, degradation and other human-disturbances. There is growing awareness that some species, like blue monkeys, may be able to persist in regenerating human-modified landscapes, where they regularly and readily use non-natural food resources. More species- and habitat-specific nutritional studies are needed to predict population-level responses to varying degrees of habitat alteration. The data generated may help us assess the potential value of human-modified habitats that may require protection, as these habitats may contribute to the persistence of primate populations around the globe, especially in novel ecosystems.

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