Differing influences of resource availability on the demographics and habitat selection of wildebeest compared with impala

2014 ◽  
Vol 30 (3) ◽  
pp. 189-198 ◽  
Author(s):  
Christopher A.J. O'Kane ◽  
Bruce R. Page ◽  
David W. Macdonald
Keyword(s):  
Habitat Selection ◽  
Fire Regimes ◽  
Perinatal Period ◽  
Dry Season ◽  
Annual Rainfall ◽  
Habitat Occupancy ◽  
Significant Relationships ◽  
Population Sizes ◽  
Mixed Feeder ◽  
Selection Of

Abstract:Although what drives the abundance and habitat selection of ungulates is a long-standing question, coherent datasets investigating the influences of rainfall, competition and fire on ungulates are unusual. Over 4 y we carried out extensive monthly road transects in Ithala Game Reserve, South Africa, to determine the demographics and habitat occupancy of the region's prevalent grazer (wildebeest) and mixed-feeder (impala). Habitat occupancy was determined using a GIS-based approach. We obtained 8742 sighting records, encompassing 8400 wildebeest and 10071 impala. Annual rainfall did not significantly correlate with population sizes of either species. Fecundity of wildebeest, but not of impala, showed a significant positive relationship with rainfall specifically over the perinatal period (November–December), whilst no significant relationships were found for either species between fecundity and rainfall over the previous year, 2 y, rut (February–April) or height of the dry season (June–August). Impala unexpectedly favoured browse habitats to grassland year round, probably consequent on competition for grass with wildebeest. Dry-season grass flushes attracted both wildebeest and impala. The study emphasized how rainfall, competition and fire regimes may affect differently grazers compared with mixed-feeders.

scholarly journals A reconstruction of the recent fire regimes of Majete Wildlife Reserve, Malawi, using remote sensing

Fire Ecology ◽  
2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Willem A. Nieman ◽  
Brian W. van Wilgen ◽  
Alison J. Leslie
Keyword(s):  
Remote Sensing ◽  
Fire Management ◽  
Fire Regime ◽  
Fire Regimes ◽  
Dry Season ◽  
Annual Rainfall ◽  
Vegetation Types ◽  
Local Evidence ◽  
Hot Dry Season ◽  
Wildlife Reserve

Abstract Background Fire is an important process that shapes the structure and functioning of African savanna ecosystems, and managers of savanna protected areas use fire to achieve ecosystem goals. Developing appropriate fire management policies should be based on an understanding of the determinants, features, and effects of prevailing fire regimes, but this information is rarely available. In this study, we report on the use of remote sensing to develop a spatially explicit dataset on past fire regimes in Majete Wildlife Reserve, Malawi, between 2001 and 2019. Moderate Resolution Imaging Spectroradiometer (MODIS) images were used to evaluate the recent fire regime for two distinct vegetation types in Majete Wildlife Reserve, namely savanna and miombo. Additionally, a comparison was made between MODIS and Visible Infrared Imager Radiometer Suite (VIIRS) images by separately evaluating selected aspects of the fire regime between 2012 and 2019. Results Mean fire return intervals were four and six years for miombo and savanna vegetation, respectively, but the distribution of fire return intervals was skewed, with a large proportion of the area burning annually or biennially, and a smaller proportion experiencing much longer fire return intervals. Variation in inter-annual rainfall also resulted in longer fire return intervals during cycles of below-average rainfall. Fires were concentrated in the hot-dry season despite a management intent to restrict burning to the cool-dry season. Mean fire intensities were generally low, but many individual fires had intensities of 14 to 18 times higher than the mean, especially in the hot-dry season. The VIIRS sensors detected many fires that were overlooked by the MODIS sensors, as images were collected at a finer scale. Conclusions Remote sensing has provided a useful basis for reconstructing the recent fire regime of Majete Wildlife Reserve, and has highlighted a current mismatch between intended fire management goals and actual trends. Managers should re-evaluate fire policies based on our findings, setting clearly defined targets for the different vegetation types and introducing flexibility to accommodate natural variation in rainfall cycles. Local evidence of the links between fires and ecological outcomes will require further research to improve fire planning.

Seasonal habitat selection of an expanding sika deer Cervus nippon population in eastern Hokkaido, Japan

2003 ◽  
Vol 9 (1) ◽  
pp. 141-153 ◽  
Author(s):  
Mayumi Sakuragi ◽  
Hiromasa Igota ◽  
Hiroyuki Uno ◽  
Koichi Kaji ◽  
Masami Kaneko ◽  
...  
Keyword(s):  
Habitat Selection ◽  
Sika Deer ◽  
Cervus Nippon ◽  
Selection Of

Factors of Habitat Selection of Acheulean Sites at Ramat Yiron, Israel

Paléorient ◽  
1981 ◽  
Vol 7 (1) ◽  
pp. 23-31 ◽  
Author(s):  
Amiel Brosh ◽  
M. Ohel
Keyword(s):  
Habitat Selection ◽  
Selection Of

Analysis of the Most Valued Organization to Work for in Spain, According to Nationality and Location

2019 ◽  
Vol 5 (2) ◽  
pp. 83-99
Author(s):  
Francisco Jesús Ferreiro Seoane ◽  
Manuel Octavio Del Campo Villares
Keyword(s):  
Work Environment ◽  
Talent Management ◽  
Point Of View ◽  
Added Value ◽  
Quantitative Character ◽  
Autonomous Communities ◽  
Professional Performance ◽  
Significant Relationships ◽  
Pearson Correlations ◽  
Selection Of

Background: The objective of this article is to analyse if there are significant relationships between the most valuable companies operating in Spain regarding professional performance, according to nationality and location within their Autonomous Communities or any superior aggrupation. To do that, a sample of 100 companies has been selected. Methods: The methodology followed is based on the selection of the 100 highestvalued companies from the point of view of Human Resources’ policy for the period 2013-2016 and through the measurement of six factors: Talent Management, Retribution, Work environment, CSR, Training and Employees’ perception, and classified by nationality and location. The study was based on 12 hypotheses, using the Unifactorial Variance’s Analysis, Pearson correlations and regressions. One limitation could be the fact that this study refers to a particular period, focusing on Spain and the variables mentioned, based on questionnaires. The added value of this work lies on the newness as it has a quantitative character, and on the fact that most of the hypotheses do not comply. Results and Conclusion: This allows to deny certain beliefs that affirm that European and American companies operating in Spain are more attractive than the Spanish or the Mediterranean ones.

scholarly journals The Winter Habitat Selection of Red Deer (Cervus elaphus) Based on a Multi-Scale Model

Animals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2454
Author(s):  
Yue Sun ◽  
Yanze Yu ◽  
Jinhao Guo ◽  
Minghai Zhang
Keyword(s):  
Habitat Selection ◽  
Environmental Factors ◽  
Cervus Elaphus ◽  
Red Deer ◽  
Scale Model ◽  
Winter Habitat ◽  
Multi Scale ◽  
Optimal Scale ◽  
Scale Models ◽  
Selection Of

Single-scale frameworks are often used to analyze the habitat selections of species. Research on habitat selection can be significantly improved using multi-scale models that enable greater in-depth analyses of the scale dependence between species and specific environmental factors. In this study, the winter habitat selection of red deer in the Gogostaihanwula Nature Reserve, Inner Mongolia, was studied using a multi-scale model. Each selected covariate was included in multi-scale models at their “characteristic scale”, and we used an all subsets approach and model selection framework to assess habitat selection. The results showed that: (1) Univariate logistic regression analysis showed that the response scale of red deer to environmental factors was different among different covariate. The optimal scale of the single covariate was 800–3200 m, slope (SLP), altitude (ELE), and ratio of deciduous broad-leaved forests were 800 m in large scale, except that the farmland ratio was 200 m in fine scale. The optimal scale of road density and grassland ratio is both 1600 m, and the optimal scale of net forest production capacity is 3200 m; (2) distance to forest edges, distance to cement roads, distance to villages, altitude, distance to all road, and slope of the region were the most important factors affecting winter habitat selection. The outcomes of this study indicate that future studies on the effectiveness of habitat selections will benefit from multi-scale models. In addition to increasing interpretive and predictive capabilities, multi-scale habitat selection models enhance our understanding of how species respond to their environments and contribute to the formulation of effective conservation and management strategies for ungulata.

Habitat selection of Cape porcupines in a farmland-suburban context in KwaZulu-Natal, South Africa

2019 ◽  
Vol 98 ◽  
pp. 111-118
Author(s):  
Samukelisiwe P. Ngcobo ◽  
Amy-Leigh Wilson ◽  
Colleen T. Downs
Keyword(s):  
South Africa ◽  
Habitat Selection ◽  
Kwazulu Natal ◽  
Selection Of

scholarly journals Mass occurrence and habitat selection of Common Redpolls (Carduelis flammea) after a large seed crop year: snow-covered ground facilitates food access

2021 ◽  
Author(s):  
Svein Dale
Keyword(s):  
Climate Change ◽  
Habitat Selection ◽  
Snow Cover ◽  
Breeding Season ◽  
Boreal Forests ◽  
Large Seed ◽  
Mass Occurrence ◽  
Seed Crops ◽  
Ecosystem Changes ◽  
Selection Of

AbstractIn boreal forests, food supplies typically have cyclic variations, and many species here fluctuate in numbers from year to year. One group of species showing large variations in population size is birds specialized on seeds from masting trees. Here, I analyze spatial patterns of a mass occurrence and habitat selection of the Common Redpoll (Carduelis flammea) during the breeding season in southeastern Norway in 2020 after a year with large seed crops from Norway Spruce (Picea abies) and Downy Birch (Betula pubescens). I found that Common Redpoll numbers increased with elevation and towards the northwest. Numbers were also strongly and positively correlated with snow depth in early April when snow was present mainly above 400 m elevation. Sites with snow cover in early April (30% of all sites) held 96.4% of all individuals recorded. Field observations indicated that Common Redpolls foraged extensively for spruce seeds on the snow until the end of May when young were independent. I suggest that the mass occurrence was due to a unique combination of exceptionally large seed crops of two tree species coinciding in the same year. The masting produced large amounts of food both for overwintering (birch seeds) and for breeding (spruce seeds), and during the breeding season snow cover facilitated access to food resources. Dependency of Common Redpolls on snow cover suggests that climate change may negatively impact some seed-eaters in boreal regions. On the other hand, higher temperatures may induce more frequent masting which may be beneficial for seed-eaters. Thus, climate change is likely to lead to complex ecosystem changes in areas where snow cover may disappear.

scholarly journals Oviposition Habitat Selection of Dengue Vectors, Aedes aegypti and Aedes albopictus in Response to Fish Predator

2016 ◽  
Vol 27 (3) ◽  
pp. 117-122 ◽  
Author(s):  
Wan Fatma Zuharah ◽  
◽  
Nik Fadzly ◽  
Wilson Kang Wei Ong ◽  
Zarul Hazrin Hashim ◽  
...  
Keyword(s):  
Habitat Selection ◽  
Aedes Aegypti ◽  
Aedes Albopictus ◽  
Fish Predator ◽  
Dengue Vectors ◽  
Selection Of

A comparison of the Charolais, British Friesian and Hereford breeds as sires of crossbred singlesuckled calves for beef production

1973 ◽  
Vol 17 (3) ◽  
pp. 267-273 ◽  
Author(s):  
R. E. Haycock ◽  
D. A. Stewart
Keyword(s):  
Weight Gain ◽  
Birth Weight ◽  
Live Weight ◽  
The Other ◽  
Cattle Production ◽  
Significant Relationships ◽  
Grazing Period ◽  
Beef Cattle Production ◽  
Breed Crosses ◽  
Selection Of

SUMMARYIn three successive years cows from an Aberdeen Angus cross Shorthorn herd were mated to pedigree Charolais, British Friesian and Hereford bulls. A comparison of the progeny of the three breeds of sire under controlled conditions was therefore possible using a random selection of dams for mating, and identical rearing of the calves. Results for live-weight gain of the suckled progeny were analysed and showed superiority of the Charolais breed over the other two when used in this form of beef cattle production.For birth weights and daily live-weight gains, particularly during the grazing period, the Charolais cross progeny showed superiority over the other two. There was a consistent although not always statistically significant tendency for these differences between the breed crosses to occur in the male calves only, the females showing little difference between breeds. The data also showed highly significant relationships between gestation period and birth weight, both within and between breed crosses.

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