Diversity of rodent and shrew assemblages in different vegetation types of the savannah biome in South Africa: no evidence for nested subsets or competition

Identifying nonrandom species composition patterns predicted by assembly rules has been a central theme in community ecology. Few studies have investigated the prevalence of multiple drivers on species composition patterns in small mammal assemblages in the Old World. This study investigated seasonal changes in rodent and shrew diversity in eleven savannah vegetation types in South Africa. We tested whether species composition patterns are nonrandom with respect to predictions from Diamond's assembly rules, niche limitation hypothesis and nestedness hypothesis. Species richness estimators indicated that inventories for the rodents (80%) and shrews (100%) were relatively complete. Rodent (n = 11 species) diversity and shrew (n = 5 species) diversity were highest in summer and lowest in autumn. Rodent richness was highest in the Terminalia sericea bushveld and woodlands and lowest in the Drypetes arguta sand forest, whilst shrew richness was highest in the T. sericea bushveld and woodlands and lowest in the Acacia nilotica/Dichrostachys cinerea open shrub savannah. We found no support for the predictions of competition and nestedness hypotheses and suggest that this was probably due to the high seasonal and annual variability in rodent and shrew diversity.     

Weeds as a predominant food source: a review of the diet of common hamsters Cricetus cricetus in farmlands and urban habitats

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Chimpanzee feeding ecology and fallback food use in the montane forest of Nyungwe National Park,Rwanda

Almost all primates experience seasonal fluctuations in the availability of key food sources. However, the degree to which this fluctuation impacts foraging behavior varies considerably. Eastern chimpanzees (Pan troglodytes schweinfurthii) in Nyungwe National Park, Rwanda, live in a montane forest environment characterized by lower primary productivity and resource diversity than low‐elevation forests. Little is known about chimpanzee feeding ecology in montane forests, and research to date predominantly relies on indirect methods such as fecal analyses. This study is the first to use mostly observational data to examine how seasonal food availability impacts the feeding ecology of montane forest chimpanzees. We examine seasonal changes in chimpanzee diet and fallback foods (FBFs) using instantaneous scan samples and fecal analyses, supported by inspection of feeding remains. Chimpanzee fruit abundance peaked during the major dry season, with a consequent change in chimpanzee diet reflecting the abundance and diversity of key fruit species. Terrestrial herbaceous vegetation was consumed throughout the year and is defined as a “filler” FBF. In contrast to studies conducted in lower‐elevation chimpanzee sites, figs (especially Ficus lutea) were preferred resources, flowers were consumed at seasonally high rates and the proportion of non‐fig fruits in the diet were relatively low in the current study. These divergences likely result from the comparatively low environmental diversity and productivity in higher‐elevation environments.     

Cape mountain zebra in the Baviaanskloof Nature Reserve,South Africa: resource use reveals limitations to zebra performance in a dystrophic mountainous ecosystem

Resource use of Cape mountain zebra was studied in the Baviaanskloof Nature Reserve (BNR) over concerns of the poor performance in population growth. We assessed the seasonal diet, habitat suitability and forage quality of the Bergplaas area in BNR for mountain zebra. Grasses contributed 95.2% to the annual diet of mountain zebra, Tristachya leucothrix contributing the most (39.4%), followed by Themeda triandra (27.6%). Seasonally, T. triandra contributed most to the diet in winter, while T. leucothrix became more important in the summer and also was the only species preferred in all seasons. Mountain zebra concentrated their feeding in Kouga Grassy Fynbos and from our assessment this was the only habitat suitable for mountain zebra. Our analysis of mountain zebra dung indicated that the seasonal nitrogen and phosphorus content was below the threshold values prescribed for grazers, and our study suggests that mountain zebra at Bergplaas are severely resource limited. We emphasize the importance of fire and access to nutrient‐rich lowlands in influencing the nutritional ecology of mountain zebra and provide conservation management recommendations.     

Diets of the African Civet Civettictis civetta (Schreber, 1778) in selected coffee forest habitat,south‐western Ethiopia

Feeding ecology of the African civet, Civettictis civetta (Schreber, 1778), was studied in selected coffee forest habitat for two seasons between December 2012 and October 2013. The study was conducted in Limu Seka district, south‐west Ethiopia. Faecal analysis was employed to assess the diet spectrum, seasonal abundance and relative importance of food items. Over 55 different food items were identified from the analysis of 387 scat samples collected during the dry and wet seasons. In the coffee forest habitat, African civets showed omnivorous feeding habit with plant‐to‐animal diet biomass ratio of 1 : 1.36. A slight diet specialization was observed during the wet season (BA = 0.46) favouring animal prey. However, during the dry season, they showed generalist feeding habit (BA = 0.87) with more plant biomass in their diet. With over 64% occurrence and 14.4% biomass, coffee berries significantly contributed to the civets dry season plant diets. The excreted coffee beans, after civets ingested ripe coffee berries, are the tastiest product used by farmers for consumption and market. Seasonal collection of civet coffee from coffee forest floor economically supports the farmers while increasing the importance of civets in the habitat and hence contributing for its conservation.     

Exudativory in the Bengal slow loris (Nycticebus bengalensis) in Trishna Wildlife Sanctuary,Tripura, northeast India

In this study we estimated the extent of exudativory in Nycticebus bengalensis and examined whether exudates can be considered as fallback foods. This study was carried out in Trishna Wildlife Sanctuary, northeastern India, in winter (December–February) and summer (March and April). We estimated time–activity budget using instantaneous sampling and used continuous focal animal sampling to record all instances and durations of feeding, over a total of 177 hr. Feeding accounted for 22.3±2.2% of the activity budget, with no seasonal difference. Bengal slow lorises fed on exudates, nectar, fruit, bark, invertebrates and avian eggs. In addition to scraping they also obtained exudates by gouging holes into the bark of trees. In winter, lorises almost exclusively fed on exudates (94.3% of winter feeding time). In summer, exudates (67.3%) and nectar from one species (22.3%) dominated the diet. This study identifies the Bengal slow loris as the most exudativorous loris. Exudates rather than being a staple fallback food, seem to be a preferred, patchily distributed and common food in the diet of the Bengal slow loris. Exudativory in this species is characterized by high selectivity among species and seasonal variation, which may be related to variations in productivity of exudates and their chemical composition. An understanding of these factors is necessary for predicting the response of this species to human disturbance such as logging. This study also underscores the importance of protecting some of the common species such as Terminalia belerica on which the loris feeds during periods of scarcity. Am. J. Primatol. 72:113–121, 2010. © 2009 Wiley‐Liss, Inc.     

Graminivory and Fallback Foods: Annual Diet Profile of Geladas (<Emphasis Type="Italic">Theropithecus gelada</Emphasis>) Living in the Simien Mountains National Park,Ethiopia

All primates show some dietary flexibility, particularly during food shortages. Foods consumed during times of scarcity (i.e., fallback foods) strongly influence the ecology and evolution of a species. Geladas (Theropithecus gelada) eat primarily graminoid leaves (i.e., grasses and sedges), but also consume other diet items (e.g., underground storage organs), especially in the dry season. We investigated the feeding ecology of wild geladas in the Sankaber region of the Simien Mountains National Park, Ethiopia across 12 mo. We asked how the gelada diet in this region, which is disturbed by livestock and agriculture, correlated with food availability and whether underground foods are fallback foods. We quantified the monthly diets of adults from eight reproductive units using instantaneous scan sampling, and seasonal aboveground and underground food availability using point-intercept transects and soil core sampling. Geladas primarily consumed graminoid leaves year-round (76.3% of the annual diet, 36.2–93.2% of the monthly diet) but spent considerable time consuming underground foods in the dry season (14.0% of the annual diet, 11.1–49.7% of the diet across dry season months). Graminoid consumption increased with graminoid availability, and underground food consumption decreased with graminoid availability. Underground food availability did not vary significantly between the dry and wet season sampling months, supporting the hypothesis that underground foods are fallback foods for geladas. We then compiled data from gelada feeding studies and found that underground foods are an important dry season diet item across study sites, but geladas rely more heavily on underground foods in habitats more heavily influenced by humans. Understanding the range and effects of primate dietary flexibility in human-modified habitats will contribute to a better understanding of how changing environments shape primate ecology and evolution.     

Diet of the South African large-spotted genet<Emphasis Type="Italic">Genetta tigrina</Emphasis> (Carnivora,Viverridae) in a coastal dune forest

We studied seasonal variations in the diet of the large-spotted genetGenetta tigrina Schreber, 1776 in the coastal dune forest of the Dwesa Nature Reserve, Eastern Cape Province, South Africa. The food items with the highest relative percentage occurrence were Coleoptera, Orthoptera and Mammalia. However, by volume they ate mostly grass then followed by Coleoptera and Orthoptera. Main prey items originated from the litter layer or low lying bushes, such as arachnids, insects, myriapods, and most mammals. The latter included ten rodent (main staple:Dendromus sp.), two golden mole and two shrew species, from 10–100 g mass. They were represented dependent on species density, but switching between seasons and habitats occupied. Birds appeared under-represented in the diet for a semi-arboreal carnivore, although this correlates with data from other studies. Remains of birds in the diet, however, peaked during winter and spring probably as a result of the main nesting period in spring. There were some variation in diet between habitats (riparian, forest and beach) and seasons. Our results show the South African large-spotted genet to have an opportunistic, generalist diet.     

Seasonal variation in food availability and relative importance of dietary items in the Gambian epauletted fruit bat (Epomophorus gambianus)

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Diet and feeding ecology of gray woolly monkeys (lagothrix lagotricha cana) in Central Amazonia: Comparisons with other Atelines

I studied gray woolly monkeys (Lagothrix lagotricha cana)in an undisturbed central Amazonian terra firme forest, near the headwaters of the Urucu river, Tefé, Amazonas, Brazil (5°50’S, 65°16’W). I report the diet and feeding ecology of a group of 39–41 individuals, based on systematic feeding observations obtained during 11 months. Woolly monkeys are primarily frugivorous; mature fruits and young seeds account for 83 and 7% of 3298 feeding records, respectively. On a seasonal basis, however, they relied heavily on young foliage (16%), seed-pod exudates (6%), and flowers (3%), particularly during the greatest annual period of ripe fruit scarcity, as determined by a phenological survey. Animals represent only 0.1% of their year-round diet, and they spent little time capturing arthropods and other prey items. Although at least 225 plant species, belonging to 116 genera and 48 families, are in their diet, the three top-ranking families (Moraceae, Sapotaceae, and Leguminosae) account for 43% of their food species and 63% of the time they spent feeding on a year-round basis. I compare the feeding ecology and diet of L. 1. canain the Urucu and other taxa of Lagothrixin upper Amazonia — the last large-bodied Neotropical primates to be studied — to those of other ateline genera: Atelesand Brachyteles. An erratum to this article is available at .