Intake and Diet Selection by Sheep Grazing Grass/Clover Patches

The effects of the spatial dispersion of ryegrass (Lolium perenne L) and clover (Trifolium repens L), at the feeding station scale, on diet composition and feeding behaviour were studied for sheep. There were no significant changes in diet composition with changes in the spatial dispersion of sward components. Bite size, bite rate and intake rate did increase as the species became more aggregated

Herbivore population regulation and resource heterogeneity in a stochastic environment.

Large-mammal herbivore populations are subject to the interaction of internal density-dependent processes and external environmental stochasticity. We disentangle these processes by linking consumer population dynamics, in a highly stochastic environment, to the availability of their key forage resource via effects on body condition and subsequent fecundity and mortality rates. Body condition and demographic rate data were obtained by monitoring 500 tagged female goats in the Richtersveld National Park, South Africa, over a three-year period. Identifying the key resource and pathway to density dependence for a population allows environmental stochasticity to be partitioned into that which has strong feedbacks to population stability, and that which does not. Our data reveal a densitydependent seasonal decline in goat body condition in response to concomitant densitydependent depletion of the dry-season forage resource. The loss in body condition reduced density-dependent pregnancy rates, litter sizes, and pre-weaning survival. Survival was lowest following the most severe dry season and for juveniles. Adult survival in the late-dry season depended on body condition in the mid-dry season. Population growth was determined by the length of the dry season and the population size in the previous year. The RNP goat population is thereby dynamically coupled primarily to its dry-season forage resource. Extreme environmental variability thus does not decouple consumer resource dynamics, in contrast to the views of nonequilibrium protagonists

Spatial impacts and the characterisation of resource use in a heterogeneous landscape.

Highly spatially variable environments pose animals with diet selection decisions that need to account for the patchy nature of their resource. Improved rangeland management would result from being able to predict patterns of animal utilisation of such vegetation. Whilst progress is being made in the comprehension of large scale influences (e.g., location of drinking water, landscape topography), little is known about how these integrate with smaller scales. It is likely that animals view landscapes in differing ways, depending on the scale that processes operate. Identification of the appropriate scale at which a species is affected by the spatial heterogeneity of a resource requires characterisation of the resource spatial structure, independent of our own biases. We tend to view landscapes in terms of vegetation communities, whilst the appropriate unit for animal perception remains unclear. This poster describes a study of foraging behaviour carried out as a method by which to associate animal activity with space use as an independent estimate of spatial heterogeneity

Oral Health Knowledge Among Patients Attending Dental OPD of Bangladesh Medical College in Relation to Gender, Generation, Education and Economic Status

This report describes a questionnaire-based study on 309 adult patients attending the Dental Outpatients Department of Bangladesh Medical College and Hospital, Dhaka during December 2000 to March 2001. The aim of the study was to determine the oral health knowledge of the patients in relation to their age, gender, economic and educational status. Almost two third (63.1%) of the subjects correctly said that pan chewing was bad for teeth. Three fourth (78.3%) of the subjects gave correct answer on question of how to prevent teeth decay. When question was asked about cause of teeth decay, bleeding gum and action of fluoride on teeth, only 38.2%, 41.4% and 32.3% could give correct answer respectively. With a few exceptions, knowledge of oral health was comparatively poor among the older generation, females, less educated and less privileged group

Spatial variation in springtime food resources influences the winter body mass of roe deer fawns. Oecologia 137

Abstract It is well established that the dynamics of mammalian populations vary in time, in relation to density and weather, and often in interaction with phenotypic differences (sex, age and social status). Habitat quality has recently been identified as another significant source of individual variability in vital rates of deer, including roe deer where spatial variations in fawn body mass were found to be only about a tenth of temporal variations. The approach used was to classify the habitat into blocks a priori, and to analyse variation in animal performance among the predefined areas. In a fine-grained approach, here we use data collected over 24 years on 1,235 roe deer fawns captured at known locations and the plant species composition sampled in 2001 at 578 sites in the ChizØ forest to determine the spatial structure at a fine scale of both vegetation and winter body mass of fawns, and then to determine links between the two. Space and time played a nearly equal role in determining fawn body masses of both sexes, each accounting for about 20% of variance and without any interaction between them. The spatial distribution of fawn body mass was perennial over the 24 years considered and predicted values showed a 2 kg range according to location in the reserve, which is much greater than suggested in previous work and is enough to have strong effects on fawn survival. The spatial distribution and the range of predicted body masses were closely similar in males and females. The result of this study is therefore consistent with the view that the life history traits of roe deer are only weakly influenced by sexual selection. The occurrence of three plant species that are known to be important food items in spring/summer roe deer diets, hornbeam (Carpinus betulus), bluebell (Hyacinthoides sp.) and Star of Bethlehem (Ornithogalum sp.) was positively related to winter fawn body mass. The occurrence of species known to be avoided in spring/summer roe deer diets [e.g. butcher's broom (Ruscus aculeatus) and beech (Fagus sylvatica)], was negatively related to fawn body mass. We conclude that the spatial variation in the body mass of fawns in winter in this forest is as important as the temporal variation, and that the distribution of plant species that are actively selected during spring and summer is an important determinant of spatial variation in winter fawn body mass. The availability of these plants is therefore likely to be a key factor in the dynamics of roe deer populations