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The spatiotemporal variations in the availability of food resources influence the movement of herbivores in a given area. In this study, variations in the selection of food resources by white rhinoceroses (Ceratotherium simum simum) was investigated in the Songimvelo Nature Reserve (South Africa) at three spatial scale levels (habitat, patch and grass species levels) during the two seasons (late wet and late dry season of a calendar year). White rhinoceros were tracked on foot, vehicle or horse, and individual groups were observed from a distance using binoculars to identify feeding habitats. At feeding habitat level, white rhinoceroses showed a preference for Low Open Woodlands and Old Lands during the late wet season but avoided Shrublands. No habitat preference was observed during the late dry season. At patch level, white rhinoceroses used patches with low rock cover and short leaf-table-height while remaining in the lower-lying areas of the Reserve. Rhinoceroses fed on grasses such as Heteropogon contortus, Themeda triandra and Eragrostis spp. during both seasons. The model selection at feeding patch level revealed that grass species presence, mean tuft diameter and species density were the most critical factors driving grass species selection in patches. This study provides evidence that white rhinoceroses’ feeding behaviour changes at different spatial scales which result in different patterns of habitat use and movement in time and space within a given area. [ABSTRACT FROM AUTHOR]

The aim of this study was to identify habitat types according to plant communities that surround the Banzi, Shokwe and Nyamithi pans located in the Ndumo Game Reserve. This hydrophytic vegetation thrives on stream and riverbanks, and thus plays a direct role in the functioning of both river systems and the flanking terrestrial landscape. Banzi, Shokwe and Nyamithi pans were classified into two different wetland systems. Banzi and Shokwe pan as a Riverine system and Nyamithi Pan as a Lacustrine system. Around the pans, 14 sampling sites were positioned and 34 quadrats or belts were sampled within these sites. Eighty-six plant species were identified around the three pans, where the dominant growth form was mostly trees. The four floristic units obtained via a classifications process were conformed into three habitat types, the Mudflat, Beach and Reedbed (MBR) Habitat Type, Riparian Forest Habitat Type and the Fringe Terrestrial Habitat Type. Due to their uniqueness, the pans add value to the Reserve and thus need to be conserved and monitored. This study provided a baseline data set by which future changes in the specific floristic characteristics (species composition, structure, cover and density) of the riparian vegetation surrounding the pans can be monitored. [ABSTRACT FROM AUTHOR]

The study compared plant and avian diversity and species composition between four habitats to review the potential implications of two distinct management practices on a forestry estate, namely to rehabilitate riparian zones to grasslands or woodlands as the two habitats that historically occurred on the property. The study habitats were Plantation (Pinus trees in riparian zone), Bushland (recently harvested), Grassland (cleared of broadleaf plants), and Woodland (control). At seven sampling sites per habitat, a vegetation assessment was conducted, while birds were caught with mist nests. Plant species richness increased from Plantation to Woodland, whereas most bird species and individuals were found in Bushland. Plant and bird species composition differed significantly between habitats. Bushland and Grassland birds were closely associated with exotic forbs. Grassland attracted birds with diverse habitat and nesting-site associations, and Woodland birds associated with woody plants. It is recommended that the majority of riparian zones be managed as grasslands, although the exact affect of the biennial summer burning and presence of exotic plants on birds needs to be investigated. To attract cavity-nesting birds to the Estate, some suitable riparian zones should be rehabilitated to Woodland by planting Ficusand Acaciatrees, as these trees are the most abundant and frequently occurring in this habitat. Rather than manage avian diversity per se, the African stonechat in Grassland and lesser honeyguide in Woodland can be employed as indicators of the rehabilitation state of the riparian zones. [ABSTRACT FROM AUTHOR]

This paper describes the design and implementation of protocol scrubbers. Protocol scrubbers are transparent, interposed mechanisms for explicitly removing network scans and attacks at various protocol layers. The transport scrubber supports downstream passive network-based intrusion detection systems by converting ambiguous network flows into well-behaved flows that are unequivocally interpreted by all downstream endpoints. The fingerprint scrubber restricts an attacker's ability to determine the operating system of a protected host. As an example, this paper presents the implementation of a TCP scrubber that eliminates insertion and evasion attacks—attacks that use ambiguities to subvert detection—on passive network-based intrusion detection systems, while preserving high performance. The TCP scrubber is based on a novel, simplified state machine that performs in a fast and scalable manner. The fingerprint scrubber is built upon the TCP scrubber and removes additional ambiguities from flows that can reveal implementation-specific details about a host's operating system. [ABSTRACT FROM AUTHOR]

Provides information on a study that investigated species diversity and habitat use by birds of riparian-plantation edges. Methodology of the study; Results and discussion on the study.

Presents a study on the effects of inadequate grassland cover for nesting on the decline of Numida meleagris in the midlands of KwaZuluNatal, South Africa. Methodology; Results and discussion; Conclusions.

Presents an investigation of the diet of pale chanting goshawks Melierax canorus that live in groups near Calitzdorp, Western Cape Province, South Africa. Most common prey based on biomass; Proportion of the biomass among the three dominant prey species; Conservation of cooperative polyandry mating system.

Abstract. The Salamander distribution system is a wide-area network data dissemination substrate that has been used daily for over a year by several groupware and webcasting Internet applications. Specifically, Salamander is designed to support push-based applications using attribute-based routing. This support provides a variety of delivery semantics ranging from collaborative group communication, used by the Upper Atmospheric Research Collaboratory (UARC) project, to basic data delivery, used by the Internet Performance Measurement and Analysis (IPMA) project. The substrate is designed to accommodate the large variation in Internet connectivity and client resources through the use of application-specific plug-in modules. This paper illustrates the architecture and design of the Salamander system driven by the needs of its set of current applications. The main architectural features described include: the attribute-based data routing mechanism, persistent data queries, negotiated push-technology, support for Application-level Quality of Service policies, and a lightweight temporal database. [ABSTRACT FROM AUTHOR]

The social organization and reproductive strategy of the Pale Chanting Goshawk Melierax canorus were investigated in four southern African study areas. Territories supporting adults additional to the breeding pair were observed in two study areas. Within one of these areas, these additional adults were either non-breeders staying in their natal territory but actively excluded from the nesting area during the breeding season or a male cobreeder participating fully in reproductive activities with the breeding pair. Polyandrous trios were, however, observed in only one vegetation type in this area, Broken Veld. The annual number of offspring fledged per group did not differ significantly between vegetation types nor between polyandrous trios and monogamous pairs within Broken Veld. Pale Chanting Goshawks lay predominantly two-egg clutches. In 2 out of 5 years, breeding groups succeeded in laying, hatching and even fledging a second brood of young after successfully fledging their first brood. Double brooding occurred more frequently in Broken Veld and most frequently in polyandrous trios in this vegetation type. To accommodate their relatively long breeding cycle (>115 days) in this temperate study area with its limiting summer breeding period, double-brooding Pale Chanting Goshawks laid the first clutch in midwinter and the second, on average, 24 days after the offspring from the first brood left the nest. [ABSTRACT FROM AUTHOR]

WE INVESTIGATED WHETHER THE FRESH green plant material with which black sparrowhawks (Accipiter melanoleucus) line their nests functions to repel insect pests and ectoparasites. When insect pest levels were elevated by means of securing an attractant (decaying meat) to the nest periphery, significantly more, and only highly volatile, Eucalyptus leaves were brought to the nest by the adult birds. At another black sparrowhawk nest, an outbreak of the haematophagous mite, Ornithonyssus bursa, was recorded one month after the birds had stopped lining the nest selectively with leaves containing high concentrations of phenolic lipids. This outbreak happened when the young had already fledged and were probably less susceptible to infestation than nestlings. The selective use of nest-lining material may serve to prevent chemically the transfer of mites from adules to the nest, and thus reduce infestation of nestlings. We discuss hypotheses and suggest future study directions for understanding the relationship between mites, their hosts, and the selective use of volatile plant chemicals. [ABSTRACT FROM AUTHOR]