Variables influencing survival in four generations of captive-born muskoxen

Since 1967, four generations of muskoxen have been born in captivity in Alaska (399 live births, 18 abortions and 47 stillbirths), all derived from 20 females and 8 males captured on Nunivak Island. Analysis of juvenile survival was accomplished by dividing individuals into 7 classes (not born live, born live but not surviving 48 hours, survived 48 hours but < 1 week, survived 1 week but < 1 month, survived 1 month but < 6 months, survived 6 months but < 2 years, survived 2 years). Males were more frequent among live born calves (219:178, P=0.05), but greater numbers of females survived to 2 years (62:86, P<0.01). Birthweight (X=9.75 kg, N=155) did not differ between sexes nor did it significantly influence survival. Of 463 individuals, 131 showed some inbreeding but no coefficients of inbreeding exceeded 0.25 and most were less than 0.13. Analysis of variance (Kruskal-Wallis) showed a significant (P<0.05) difference between survival of inbred and non-inbred individuals. Chi-squared tests showed a greater proportion of non-inbred calves surviving to 2 years (P<0.05) but no significant differences in perinatal mortality. Offspring of the Nunivak Island cows survived significantly (P<.01) longer than those whose mothers were born in captivity, even when only non-inbred calves were compared

Dry season foraging preferences of cattle and sheep in a communal area of South Africa.

We examined landscape and habitat (vegetation) scale foraging of cattle and sheep at two communal villages in the Eastern Cape, South Africa, to determine the key resources utilised during the dry season. At the landscape scale, cattle at both sites displayed overall preference for the arable lands at this time, although this diminished steadily as the dry season progressed. In contrast, sheep made considerably less use of these areas, showing only sporadic preference. At the vegetation scale, cattle demonstrated greatest preference for crop residues and uncultivated ‘commonage' areas, although foraging in grassland increased considerably in the latter stages of the dry season. Sheep utilised a much smaller range of vegetation types, preferring crop residues and fields that had been recently fallow and avoiding all other vegetation categories. We suggest that given the spatial limitations in planned, communal villages, the arable lands function as key resource areas for livestock during the dry season. It is recommended that management of these areas emphasise greater integration of sheep and cattle grazing and focus on maintaining vegetation heterogeneity in order to facilitate opportunistic ‘switching' in foraging patterns at different stages of the dry season.African Journal of Range & Forage Science 2007, 24(3): 109–12

Livelihoods and landscapes: the people of Guquka and Koloni and their resources

This book analyses changes in the use of the landscape and the nature of rural livelihoods in two South African villages - Guquka and Koloni in the former Ciskei homeland. Taking an interdisciplinary approach on how livelihoods and landscapes in the Eastern Cape link the book provides a study of the patterns of land use over time. It depicts the steady deterioration in agricultural production and the corresponding increase in dependence on social grants and wages. It shows that despite this trend remnants of a peasantry do exist. Contributions: Investigating rural livelihoods and landscapes in Guquka and Koloni: an introduction (Paul Hebinck); Rural transformation in the Eastern Cape (Paul Hebinck and Wim van Averbeke); Agro-ecology, land use and smallholder farming in the central Eastern Cape (Wim van Averbeke and James Bennett); A social history of Guquka and Koloni: settlement and resources (Paul Hebinck and Lothar Smith); Natural resource base and agricultural potentials (Peter C. Lent); Local governance and institutions (Wim van Averbeke and James Bennett); The view from above: a history of land use in Guquka and Koloni, 1938-1996) (Peter C. Lent and Guilty Mupakati); Production of crops in arable fields and home gardens (Paul Hebinck and Nomakaya Monde); Livestock production and forage resources (James Bennett and Peter C. Lent); Gathering from the land (Peter C. Lent); Mobility and population dynamics (Lothar Smith and Paul Hebinck); Contemporary livelihoods (Wim van Averbeke and Paul Hebinck); Life histories and livelihood trajectories (Paul Hebinck et al.); Livelihoods and landscapes: people, resources and land use (Paul Hebinck and Wim van Averbeke). [ASC Leiden abstract]ASC – Publicaties niet-programma gebonde

A comparison of faecal analysis with backtracking to determine the diet composition and species preference of the black rhinoceros (Diceros bicornis minor)

The diet of black rhinoceros (Diceros bicornis minor) was studied using backtracking and faecal analysis in South Africa. Both methods yielded different results, with a large bias for dominant species. Results of backtracking showed that the rhinos browsed on 80 plant species. Grasses comprised 4.5% of the diet in the faecal analysis, but were not recorded during the backtracking. The backtracking method, along with a measure of forage availability, was used to identify two groups of plant species, those species taken in a higher proportion than available in the field and those taken in a lower proportion. Chemical analyses showed that these two species groups were similar in in vitro digestibility, macro-elements and fibre constituents. Mean bite size and species contribution to the diet were not correlated with any of the forage quality parameters, indicating that rhinos were not maximising nutrient intake or minimising fibre intake of these consumed plant species

Livelihoods and landscapes: the people of Guquka and Koloni and their resources

This book analyses changes in the use of the landscape and the nature of rural livelihoods in two South African villages - Guquka and Koloni in the former Ciskei homeland. Taking an interdisciplinary approach on how livelihoods and landscapes in the Eastern Cape link the book provides a study of the patterns of land use over time. It depicts the steady deterioration in agricultural production and the corresponding increase in dependence on social grants and wages. It shows that despite this trend remnants of a peasantry do exist. Contributions: Investigating rural livelihoods and landscapes in Guquka and Koloni: an introduction (Paul Hebinck); Rural transformation in the Eastern Cape (Paul Hebinck and Wim van Averbeke); Agro-ecology, land use and smallholder farming in the central Eastern Cape (Wim van Averbeke and James Bennett); A social history of Guquka and Koloni: settlement and resources (Paul Hebinck and Lothar Smith); Natural resource base and agricultural potentials (Peter C. Lent); Local governance and institutions (Wim van Averbeke and James Bennett); The view from above: a history of land use in Guquka and Koloni, 1938-1996) (Peter C. Lent and Guilty Mupakati); Production of crops in arable fields and home gardens (Paul Hebinck and Nomakaya Monde); Livestock production and forage resources (James Bennett and Peter C. Lent); Gathering from the land (Peter C. Lent); Mobility and population dynamics (Lothar Smith and Paul Hebinck); Contemporary livelihoods (Wim van Averbeke and Paul Hebinck); Life histories and livelihood trajectories (Paul Hebinck et al.); Livelihoods and landscapes: people, resources and land use (Paul Hebinck and Wim van Averbeke). [ASC Leiden abstract]</p

Continued decline in tree euphorbias (Euphorbia tetragona and E. triangularis) on the Great Fish River Reserve, Eastern Cape, South Africa

A dramatic decline averaging 43% over a 4-year period has occurred in tree Euphorbia (Euphorbia tetragona and Euphorbia triangularis) populations on the Great Fish River Reserve, South Africa. These changes are evident from data gathered by general vegetation monitoring methods as well as from a focused study of four tree Euphorbia populations. The decline from 2003 to 2007 was more marked for E. triangularis than for E. tetragona and was accompanied by a general absence of seedlings and a reduced presence of younger age classes of both species, decreasing the proportion of younger trees in the populations. The role of megaherbivores, specifically the black rhinoceros, in these changes is well established. However, the impact of baboon activity, leading to damage to tree crowns and upper branches, is also substantial, especially on E. triangularis populations. Damaged crowns were recorded significantly more often for E. triangularis than for E. tetragona, and the damage frequency increased with decreasing tree height. Thus, our work provides the first evidence that these two closely related Euphorbia species may be affected differently by herbivory

Impact of black rhinoceros (Diceros bicornis minor) on a local population of Euphorbia bothae in the Great Fish River Reserve, South Africa

In the Great Fish River Reserve, South Africa, black rhinoceros (Diceros bicornis minor) feed extensively on a local population of Euphorbia bothae. Maintaining the endangered black rhinoceros and the protected E. bothae population are both conservation priorities of the reserve. Therefore, the sustainability of this plant–animal interaction was investigated by comparing population characteristics, browsing incidence and intensity within the reserve and in an adjacent exclosure without access to rhino. Fixed-point photographs showed that over a 2-month period 36.6% of 213 monitored plants were browsed, with an average biomass loss of 13%, and 1% were destroyed. Of 26 plants re-photographed after approximately 3 years, 70% showed a decrease in biomass, averaging 37.8% over this period. In this time span, 19% of the monitored plants died. Small plants