Search the Article Database:

Search our library of articles, papers and other published materials. You can use keywords or boolean-style search:

Ramifying effects of the risk of predation on African multi-predator, multiprey large-mammal assemblages and the conservation implications

Impacts of predators on prey populations are incurred not only through mortality inflicted, but also from how the risk of mortality affects the behaviour, spatial distribution and resource access of potential prey species. This risk is governed by exposure to predators and vulnerability following encounters. Behavioural responses to reduce risks have ramifying consequences for habitat partitioning, regional distributions and local impacts of herbivores on vegetation. These consequences are reviewed for carnivore-ungulate assemblages in African savanna ecosystems. Vigilance serves multiple functions,

View Details + Download

Placental morphology in African antelopes and giraffes

Delivered placentas from nineteen antelopes and five giraffes and placentas from five antelopes dead during parturition and eight antelopes dead during advanced pregnancy were morphologically examined. Placental length and weight, arrangement, number and size of cotyledons, and other features were recorded wherever the conditions of placentas permitted. Cotyledon rows corresponded to the caruncle rows on uterine walls. The number of rows was usually four, although in Hippotraginae it was six to eight and in Reduncinae it was two. Numbers of

View Details + Download

Mother-young relationships in captive ungulates: variability and clustering

We recorded four measures of mother-young association and the percentage of time the young spent lying during the first week after birth for 59 mother-young pairs belonging to 22 species and seven families of ungulates. The measures of mother-young association were positively correlated with each other and negatively correlated with the percentage of time the young spent lying. Three cluster analyses, based on various combinations of measures, separated the bovids into two groups recognizable as `followers’ and ‘hiders’. When the

View Details + Download

The effects of increased hay-to-grain ratio on behavior, metabolic health measures, and fecal bacterial communities in four Masai giraffe (Giraffa camelopardalis tippelskirchi) at Cleveland Metroparks Zoo

We evaluated whether increasing the hay-to-grain ratio offered to Masai giraffe (Giraffa camelopardalis tippelskirchi) at Cleveland Metroparks Zoo would reduce oral stereotypies and alter feeding behaviors, maintain or increase serum calcium-to-phosphorus ratio, decrease serum insulin-to-glucose ratio and salivary insulin, and alter fecal bacterial community structure. Giraffe transitioned to a ∼90:10 hay-to-grain ratio in even increments over 8 weeks. A ration balancer was added during the seventh week of transition to ensure proper mineral and nutrient balance. We collected (1) behavioral

View Details + Download

DNA metabarcoding illuminates dietary niche partitioning by African large herbivores

Niche partitioning facilitates species coexistence in a world of limited resources, thereby enriching biodiversity. For decades, biologists have sought to understand how diverse assemblages of large mammalian herbivores (LMH) partition food resources. Several complementary mechanisms have been identified, including differential consumption of grasses versus nongrasses and spatiotemporal stratification in use of different parts of the same plant. However, the extent to which LMH partition food-plant species is largely unknown because comprehensive species-level identification is prohibitively difficult with traditional methods. We

View Details + Download

Dynamics of ungulates in relation to climatic and land use changes in an insularized African savanna ecosystem

Land use change and human population growth are accelerating the fragmentation and insularization of wildlife habitats worldwide. The conservation and management of wildlife in the resultant ‘island’ ecosystems in the context of global warming is challenging due to the isolation and reduced size of the ecosystems and hence the scale over which ecosystem processes can operate. We analyzed trends in numbers of nine large herbivores in Kenya’s Lake Nakuru National Park to understand how rainfall and temperature variability, surrounding land

View Details + Download

The structure of the masseter muscle in the giraffe (Giraffa camelopardalis)

In the giraffe (Giraffa camelopardalis), the masseter muscle was divided into several layers. The superficial and more medial (second) tendinous sheets of the masseter muscle fused with each other at the dorso-caudal part and a fleshy portion was located between these tendinous sheets. In the rostral part, the most superficial tendinous sheet turned around as a compact tendon and attached to the facial crest (Crista facialis). The turned tendinous sheet, however, never fused with the second tendinous sheet and this

View Details + Download

Urinary steroid evaluations to monitor ovarian function in exotic ungulates: II. Comparison between the giraffe (giraffa camelopardalis) and the okapi (okapia johnstoni)

Ovarian activity in the female giraffe was evaluated during the nonfertile ovarian cycle and during the terminal stages of gestation. Progesterone metabolites, in the form of pregnanediol‐3‐glucuronide (PdG), were measured in daily random urine samples collected from four adult parous giraffes. The follicular phase averaged 4.0 ± 0.1 days in length (N = 12; range 3–5 days) and peak PdG levels in the postovulatory period averaged 30.9 ± 1.7 ng/mg Cr (N = 12). PdG levels during the latter half

View Details + Download

Nasal heat exchange in the giraffe and other large mammals

The respiratory air of the giraffe is exhaled at temperatures substantially below body core temperature. As a consequence, the water content of the exhaled air is reduced to levels below that in pulmonary air, resulting in substantial reductions in respiratory water loss. Measurements under outdoor conditions showed that at an ambient air temperature of 24 degrees C, the exhaled air was 7 degrees C below body core temperature, and at ambient air temperature of 17 degrees C, the exhaled air

View Details + Download

Demography of giraffe in the fragmented Tarangire Ecosystem

Documenting whether variation in demographic parameters such as births, deaths, and movement exists, and how temporal and spatial environmental variability influences demography, is critical to understanding and affecting changes in animal populations. Natural populations often exhibit variation in demographic parameters, and while the examination of temporal variation has long been a central theme in population ecology, spatial variation among or within populations of the same species has received much less attention. Although the vast majority of the world’s ungulate species

View Details + Download