Habitat, Space Use and Feeding Ecology of the African Buffalo

The conservation of biodiversity and natural resources relies to a large extent on the establishment of
\nprotected areas. However, protected areas often fail to meet the objectives that lead to their establishment,
\ndue to poor control over the manifold, legal and illegal human activities within protected areas,
\ninsufficient knowledge about system characteristics, in particular with respect to disturbance regimes,
\nand due to inappropriate management strategies and means of implementation.
\nThe study investigates the responses of large herbivores to anthropogenic disturbances in Queen
\nElizabeth National Park (QENP), Uganda. Unique features of QENP are high human population densities
\nwithin and outside the park and a high degree of habitat fragmentation, resulting from natural (topography,
\nlakes, channel) and anthropogenic (villages, roads, cattle pastures) factors. Outstanding
\ndisturbances are man-made fires that frequently devastate large parts of the park. Fire frequency and
\nseverity have increased over the last decades, leading to widespread and long-lasting loss of herbivore
\nfeeding grounds.
\nThe study is based on the assumption that the present fire regime, in combination with other anthropogenic
\ndisturbances adversely affects the population development of the abundant large grazers in
\nQENP under the local geo-ecological conditions. The main goals of this study are (1) to establish spatial
\nand temporal habitat utilisation patterns of buffalo (Syncerus caffer), Uganda kob (Kobus kob thomasi)
\nand hippopotamus (Hippopotamus amphibius) in relation to the prevailing fire regime and other
\nanthropogenic disturbances, and (2) to provide baseline data for the elaboration of a fire management
\nplan.
\nThe study area is dominated by grassland in the central parts and bush-land with variable densities of
\nbushes towards the water. Most of the study area is surrounded by water. Point surveys were conducted
\nto estimate the distribution and abundance of the focal species, using Distance sampling. Environmental
\nand anthropogenic factors were quantified by distances from each observation point using a
\nGeographic Information System (GIS). All geo-referenced data were subject to multiple regression
\nanalyses. Regression models for several stages of vegetation development before and after burning
\nwere used to evaluate the spatial and temporal relationship between different disturbance factors and
\nlarge herbivore abundance.
\nThe effects of increasingly frequent fires over the last decades in the study area are the spread of fire
\nclimax plant species such as Acacia sieberiana and shrubs of Acacia hockii, the spread of Imperata
\ncylindrica, a widely indigestible grass species, and species-poor overgrazed grasslands in the main
\ndistribution area of Uganda kob.
\nThe distribution of Uganda kob is generally restricted to open grasslands and near to water in the
\nNorth and East of the study area. Their movements in postfire-periods largely depend on the locality of
\nburnt areas. Fresh pasture after burns is highly attractive to Uganda kob in all stages of postfire-development.
\nHowever, adult males can suffer from food shortage after burns due to their strong attachment to their mating grounds (leks). Uganda kob does not show significant avoidance with regard to
\nhuman activities, villages and roads. They are mostly affected by the decrease of suitable pasture in
\nparts of the study area due to the encroachment of Imperata cylindrica. The data collected show that
\ndensity of Uganda kob has significantly reduced in the western part of the study area where they were
\nwidely distributed two decades ago. In addition, the combination of frequent fires and heavy grazing
\nafter burns led to a loss of high quality grass species in their main distribution areas.
\nThe distribution patterns of buffalo are characterised by an accumulation of large herds in the central
\ngrasslands of the study area, while smaller herds occupy bush-land closer to the water. In postfireperiods
\nbuffaloes prefer tall grass savanna in the southern part of the study area. They utilise postfire
\npasture in burnt areas only in advanced stages of vegetation development. Buffaloes are affected by
\nall quantified anthropogenic disturbances. They clearly avoid the vicinity of villages. The main road
\nthrough the park restricts the movements of buffalo herds. Adverse effects of the habitat fragmentation
\nbecome evident when home ranges of buffalo herds are burnt to a large extent. One of the outstanding
\nthreats to buffalo is, however, competition with life-stock. Over the last decades buffaloes have
\nnearly disappeared in areas with live-stock occupancy. Furthermore, inter-specific competition is probable
\nbetween buffalo and hippopotamus in their feeding grounds along the water in postfire-periods.
\nHippopotamuses are still abundant in large numbers in the study area. At present, they seem not to be
\naffected by anthropogenic disturbances, apart from poaching.
\nThe equilibrium of population sizes of the mega-herbivores hippopotamus and elephant (Loxodonta
\nafricana) is important for maintaining the savanna structure in the study area, and in consequence for
\nthe viability of other herbivores. Since elephants are not abundant in high numbers, the spread of
\nbushes is one of the aspects to be monitored with respect to habitat availability (open grasslands) for
\nother large herbivores. Appropriate fire management strategies could regulate the grassland-bushland
\nmosaic in the study area.
\nFire management is a tool to avoid adverse and amplify advantageous effects of fire on the habitats of
\nherbivores. Recommendations for fire management in terms of controlled burning and protection from
\nfires are given on the base of habitat classification that specifies temporal, spatial and functional aspects
\nof the habitat use of large herbivores in time and space. The dynamic interrelations of anthropogenic
\nand natural factors described may additionally contribute to adaptive strategies for the protection
\nof wildlife in QENP.

Habitat selection, foraging ecology and conservation of Eastern Curlews on their non-breeding grounds

Excel files containing source data for habitat selection

Urbanization and anthropic influences can drastically modify a natural habitat and transform it into an easily recognizable "urban habitat". Human activities can also induce less severe modifications of what apparently might still look like natural habitats. Therefore, these subtle alterations may be hidden but can still cause important negative effects on plant and animals. In contrast, some species seem able to take advantage of these anthropic alterations. Here, we examined the possible effects of the anthropogenic disturbance of an apparent natural habitat on the feeding ecology and body condition of Moorish geckos, Tarentola mauritanica. For this, we compared microhabitat structure, invertebrate availability, the diet composition (estimated from fecal contents), diet selection patterns and body condition of the two populations of geckos inhabiting two contiguous small islands. These islands have similar environmental characteristics, but highly contrasting differences in urbanization and anthropogenic influence. We found that, although the abundance of potential invertebrate prey was similar on both habitats, the diversity of invertebrate prey was lower in the altered habitat. As a consequence, although composition of the diet of geckos was similar on both islands, the diversity of prey and food niche breadth were lower in the altered habitat, and patterns of diet selection changed. However, these inter-habitat differences did not seem to affect the body size and body condition of geckos. We discuss how flexibility in feeding ecology may allow some species to cope with small anthropic disturbances of the habitat.

Drylands occupy about one-third of the world's land surface area and rivers in these regions have less predictable flow regimes than those in humid tropical and temperate regions. Australia's dryland river-floodplain systems cycle through recurrent periods of floods and droughts, oflen resulting in extreme hydrological variability. As a result, these systems have been described as having a 'boom and boost' ecology with periods of high productivity associated with flooding. Not surprisingly, flow and its variability have been recognised as major driving forces in the ecological functioning of Australian rivers and responses to flow variability from fish and aquatic invertebrates have been reasonably well described. Furthermore, the reduced amount of water reaching floodplain waterbodies due to river regulation has been held responsible for successional changes in aquatic biota and, consequently, the resources available for both fish and invertebrates. However, information regarding the impacts of water resource development has generally focused on within-channel processes of Australian rivers, not on floodplains, which are arguably more affected by water development. The following dissertation is concerned with how different types of natural and modified floodplain lagoons are able to trophically support their fish communities in the floodplain of the Macintyre River, Border Rivers catchment (QLD/NSW), a regulated dryland river. This study focuses on the influence of flooding and the implications of an extended dry period, and different levels of flow regulation, on the feeding ecology of selected fish species (Ambassis agassizil, Lelopotherapon unicolor and Nematalosa erebi) between 2001 and 2003. Food resources consumed by fish are hypothesised to vary in response to flooding, when inundation of isolated lagoons and vast floodplain areas can result in a burst of primary and secondary productivity. Given the permanently elevated water levels of some regulated floodplain lagoons, fish diets are hypothesised to be less variable in these floodplain habitats in comparison to diets of fish from floodplain lagoons with natural flow and water regime. Feeding ecology is examined firstly, in terms of diet composition of selected fish species, using stomach content analysis, and secondly, in relation to possible energy sources sustaining fish (using stable isotope analysis) in selected floodplain lagoons and a site in the main channel of the Macintyre River. The information produced should allow managers to take variations in food resources, food web structure and dietary ecology into account in management regimes for refugia and dryland systems in general. Factors such as diel and ontogenetic variations in dietary composition and food intake by fish are shown to considerably affect ovemll dietary patterns of each study species. Therefore, it is important to understand the contributions of such factors to the variability of fish dietary patterns before performing studies on resource use by fish in floodplain habitats of the Macintyre River. Major food categories consumed by the study species were zooplankton, aquatic invertebrates and detrital material. Zooplankton was of particular importance as this food item was ingested by all three study species at some stage of their life history. Spatial and temporal variation in diet composition of the study species was mostly associated with changes in prey items available across floodplain habitats and between seasons (summer/winter). The low magnitude of flooding events during the study period is arguably the most likely factor influencing the lack of patterns of variation in fish diets in floodplain habitats subject to flooding, whereas in non-flooded lagoons the observed dietary variation was a consequence of successional changes in composition of the aquatic fauna as the dry season progressed. Water regime had an important effect on differences in fish diet composition across lagoons, but further evaluation of the influence of flooding is needed due to overall lack of major flooding events during the study period. Autochthonous resources, namely plankton, were the basis of the food web and phytoplankton in the seston is the most likely ultimate energy source for fish consumers, via planktonic suspension feeders (zooplankton). Nevertheless, organic mailer could not be disregarded as an important energy source for invertebrates and higher consumers. In general, the present study does not provide support for the major models predicting the ftinctioning of large rivers, such as the River Continuum Concept and Flood Pulse Concept, which argue that allochthonous organic matter either from upstream or from the floodplain are the most important sources of carbon supporting higher consumers. In contrast, the Riverine Productivity Model would be more appropriate to describe the food web and energy sources for consumers in the Macintyre River floodplain as this model suggests that local productivity, based on autochthonous phytoplankton and organic matter, ftiels food webs in large rivers. The results of this study suggest that factors known to affect phytoplankton production in floodplain lagoons (e.g. flow regulation, turbidity and nutrient/herbicide inputs) must be seriously considered in current landscape and water management practices.

This work examines whether stepwise discriminant function analysis of a suite of craniodental variables enables feeding behaviour and habitat preferences to be identified in fossil ungulates. There are several morphological features of the ungulate skull, mandible and dentition that are well correlated with dietary adaptations, and thus can be used for estimating the feeding ecology of extinct taxa. However, most studies have followed an univariate approach for characterizing the relationship between diet and craniodental structure in extant ungulates (but see Pérez‐Barberia & Gordon, 2001), even though such a relationship has been revealed to be complex because of functional, phylogenetic and biomechanical constraints. In this paper a multivariate perspective is followed, developing quadratic discriminant functions for pairwise comparisons of dietary/habitat groups in modern species. Given that the stepwise method for selecting the morphological variables to be included in the algorithms was used, alternative discriminant functions are provided. Results obtained show that these algorithms reclassify correctly the species according to their feeding and habitat ecology, and thus may be useful for obtaining reliable palaeoautecological inferences (i.e. those related to the life style of extinct species, such as feeding ecology and habitat preferences) when applied to extinct ungulate taxa.

Turtles (Testudinata) are a diverse group of reptiles that conquered a broad set of habitats and feeding ecologies over the course of their well‐documented evolutionary history. We here investigate the cranial shape of 171 representatives of the turtle lineage and the relationship of shape to different habitat and diet preferences using two‐dimensional geometric morphometrics. The skull shape of extant turtles correlates with both ecological proxies, but is more affected by habitat than diet. However, the application of these correlations to extinct turtles produces mostly flawed results, as least when compared to external data such as sedimentary environment, highlighting that the morphospace held by extant turtles is not necessarily the optimal location in tree space for a particular ecology. The inability of this study to correctly predict the ecology of extinct turtles is likely related to the fact that the shape of turtle skulls is dominated by the emarginations and jaw closure mechanisms, two shape features unrelated to habitat or feeding ecology. This indicates that various specializations that are apparent in the skull only contribute little to overall shape.

Experimental work on captive Goffin’s cockatoos (Cacatua goffiniana) has highlighted the remarkable cognitive abilities of this species. However, little is known about its behavior in the natural habitat on the Tanimbar Archipelago in Indonesia. In order to fully understand the evolutionary roots leading to cognitively advanced skills, such as multi-step problem solving or flexible tool use and manufacture, it is crucial to study the ecological challenges faced by the respective species in the wild. The three-month expedition presented here aimed at gaining first insights into the cockatoos’ feeding ecology and breeding behavior. We could confirm previous predictions that Goffin’s cockatoos are opportunistic foragers and consume a variety of resources (seeds, fruit, inflorescence, roots). Their breeding season may be estimated to start between June and early July and they face potential predation from ground and aerial predators. Additionally, the observational data provide indications that Goffin’s cockatoos are extractive foragers, which together with relying on multiple food sources might be considered a prerequisite of tool use.

Tick-borne pathogens (TBPs) are a growing global concern, contributing to emerging and re-emerging diseases in humans and animals. Human encroachment into natural habitats and unregulated wildlife translocations are key drivers of TBP emergence, as they expand wildlife-livestock-human interfaces and facilitate the introduction of alien TBPs into naïve hosts and new regions. Accurate molecular surveillance is essential to guide management strategies and prevent clinical outbreaks. This study conducted a cross-sectional molecular screening of TBPs in wildlife from 22 host species sampled over a four year period from 2021 to 2024 across eight South African protected areas: Kruger (KNP), Karoo (KaNP), Camdeboo (CaNP), Mountain Zebra (MZNP), Mokala (MokNP), and Addo Elephant (AENP) National Parks, as well as Lapalala Wilderness (LWR), and Timbavati (TPNR) Nature Reserves. A total of 572 spleen, liver and blood samples were tested for Anaplasma, Ehrlichia, Rickettsia, Coxiella, Theileria and Babesia spp. using Reverse Line Blot hybridization, with confirmation by Sanger sequencing and phylogenetic analysis. Prevalence, confidence intervals, risk factors and co-infections were also assessed. High prevalence (50-100 %) of Anaplasma/Ehrlichia and Theileria/Babesia spp. was recorded. Anaplasma marginale was detected in African buffalo (Syncerus caffer; KNP), kudu (Tragelaphus strepsiceros; CaNP), warthog (Phacochoerus africanus; AENP), hippo (Hippopotamus amphibius; TPNR), and eland (Taurotragus oryx; KaNP), while zoonotic A. capra was found in a hippo. Coxiella burnetii was detected in all sampled areas and in multiple species, including African buffalo, wild dog (Lycaon pictus), black wildebeest (Connochaetes gnou), eland, gemsbok (Oryx gazella), zebra (Equus quagga), hartebeest (Alcelaphus buselaphus), springbok (Antidorcas marsupialis), and warthog. SFG Rickettsia spp., including R. africae and R. felis, were detected in 18 animals. Babesia bigemina was found in springbok (MokNP). These findings reveal widespread TBP presence in South African wildlife and highlight the need for ongoing surveillance to mitigate spillover risks and protect ecosystems and public health. While high prevalences were observed, clinical impacts of these infections on wildlife remain unclear.

This article describes the design, construction, and field‐testing of a standalone networked animal‐borne monitoring system conceived to study community ecology remotely. The system consists of an assemblage of identical battery‐powered sensing devices with wireless communication capabilities that are each collar‐mounted on a study animal and together form a mobile ad hoc network. The sensing modalities of each device include high‐definition video, inertial accelerometry, and location resolved via a global positioning system module. Our system is conceived to use information exchange across the network to enable the devices to jointly decide without supervision when and how to use each sensing modality. The ultimate goal is to extend battery life while making sure that important events are appropriately documented. This requires judicious use of highly informative but power‐hungry sensing modalities, such as video, because battery capacity is constrained by stringent weight and dimension restrictions. We have proposed algorithms to regulate sensing rates, data transmission among devices, and triggering for video recording based on location and animal group movements and configuration. We have also developed the hardware and firmware of our devices to reliably execute these algorithms in the exacting conditions of real‐life deployments. We describe validation of the performance and reliability of our system using deployment results for a mission in Gorongosa National Park (Mozambique) to monitor two species in their natural habitat: the waterbuck and the African buffalo. We present movement data and snapshots of animal point‐of‐view videos collected by 14 fully operational devices collared on 10 waterbucks and 4 buffaloes.

Among wildlife, the African buffalo seems to be the only long-term maintenance host of FMDV, but, as far as is known, this is confined to SAT-type viruses. Why other types of FMDV are apparently not maintained by buffalo remains to be explained. It is clear furthermore that buffalo transmit SAT viruses, albeit rarely, to other susceptible species with which they come in contact but the mechanisms whereby this occurs remain to be fully elucidated. The fact that buffalo do this presents a fundamental quandary for development and intensification of livestock farming in sub-Saharan Africa, especially where export of livestock and their products is the objective. This makes livestock development within integrated pastoral/wildlife systems problematic. Controlling FMD by vaccination of wildlife in sub-Saharan Africa is not feasible because of the logistical problems of vaccinating large numbers of free-ranging animals. Furthermore, FMD vaccines appear to be less effective in some wildlife species than in livestock and, as has been shown in livestock, currently available FMD vaccines do not necessarily protect against infection as opposed to disease. Available inactivated vaccines also only provide transient immunity and need to be administered repeatedly to maintain high levels of herd immunity. The use of fencing to separate wildlife potentially infected with FMDV from livestock has been used successfully in southern Africa to prevent outbreaks in the latter and the possible extension of this approach to other regions of sub-Saharan Africa is a subject of debate. It is strongly opposed by the environmental lobby but, on the other hand, unless ways of profiting from the large livestock populations of the arid and semi-arid regions of sub-Saharan Africa can be found, the human populations of those regions will be consigned to continuing poverty for the foreseeable future.

BackgroundAssessing wildlife movements and habitat use is important for species conservation and management and can be informative for understanding population dynamics. The African buffalo (Syncerus caffer) population of Ruaha National Park, Tanzania has been declining, and little was known about the movement, habitat selection, and space use of the population, which is important for understanding possible reasons behind the decline. A total of 12 African buffalo cows from four different herds were collared with satellite transmitters. Movements were assessed over 2 years from 11 animals.ResultsThe space use of the individual collared buffaloes as an approximation of the 95% home range size estimated using Brownian bridge models, ranged from 73 to 601 km2. The estimated home ranges were larger in the wet season than in the dry season. With the exception of one buffalo all collared animals completed a wet season migration of varying distances. A consistent pattern of seasonal movement was observed with one herd, whereas the other herds did not behave the same way in the two wet seasons that they were tracked. Herd splitting and herd switching occurred on multiple occasions. Buffaloes strongly associated with habitats near the Great Ruaha River in the dry season and had little association to permanent water sources in the wet season. Daily movements averaged 4.6 km (standard deviation, SD = 2.6 km), with the longest distances traveled during November (mean 6.9 km, SD = 3.6 km) at the end of the dry season and beginning of the wet season. The shortest daily distances traveled occurred in the wet season in April–June (mean 3.6 km, SD = 1.6–1.8 km).ConclusionThe Great Ruaha River has experienced significant drying in the last decades due to water diversions upstream, which likely has reduced the suitable range for buffaloes. The loss of dry season habitat due to water scarcity has likely contributed to the population decline of the Ruaha buffaloes.

Common marmosets have been widely used in biomedical research for years. Nutritional control is an important factor in managing their health, and insect intake would be beneficial for that purpose because common marmosets frequently feed on insects in natural habitats. Here, we examined the effect of enhanced insect feeding on the gut by analysing the faecal microbiota and transcripts of captive marmosets. A family consisting of six marmosets was divided into two groups. During the seven-day intervention period, one group (the insect feeding group, or Group IF) was fed one cricket and one giant mealworm per marmoset per day, while the other (the control group, or Group C) was not fed these insects. RNA was extracted from faecal samples to evaluate the ecology and transcripts of the microbiota, which were then compared among time points before (Pre), immediately after (Post), and two weeks after the intervention (Follow_up) using total RNA sequencing. The gut microbiota of marmosets showed Firmicutes, Actinobacteria, Bacteroidetes, and Proteobacteria as dominant phyla. Linear discriminant analysis showed differential characteristics of microbiota with and without insect feeding treatment. Further analysis of differentially expressed genes revealed increases and decreases in Bacteroidetes and Firmicutes, respectively, corresponding to the availability of insects under both Post and Follow_up conditions. Significant changes specific to insect feeding were also detected within the transcriptome, some of which were synchronized with the fluctuations in the microbiota, suggesting a functional correlation or interaction between the two. The rapid changes in the microbiota and transcripts may be achieved by the microbiota community originally developed in the wild through marmosets’ feeding ecology. The results were informative for identifying the physiological impact of insect feeding to produce a better food regimen and for detecting transcripts that are currently unidentifiable.

Feeding Ecology and Development of Juvenile Black Ducks in Maine

Traditionally, it has been assumed that re­ef fish recruitment is a density dependent pro­cess determined by adult population size and resource limitations (Sale 1978). More recent ideas on factors regulating population size in­clude the concept that reef populations are strongly influenced by pre-recruitment limita­tions (Victor 1986, Richards and Lindeman 1987, Doherty and Williams 1988). Variation in larval survival rates due to starvation can strongly affect year class strength. Finding ap­propriate planktonic prey within a few days of hatching is critical to larval survival. However, little is known about the diets of early (prefle­xion) larval reef fishes, thus studies of their feeding ecology would provide insight into survi­val and subsequent recruitment to reefs. A ma­ jor limitation to such studies has been the low yield of reef fish larvae in plankton tows (Victor 1986, Leis 1989). Light traps are an at­ tractive alternative since many fish larvae are attracted to light, and traps can be easily deplo­yed in shallow reef sites. We conducted a study to examine the diets of tropical fish larvae co­llected by light traps and plankton tows at dif­ferent habitats on a shallow coral reef. Our ob­jective was to collect first feeding preflexion larvae and to identify prey organisms in their guts. This information is needed for our long term goal of culturing coral reef fishes in the laboratory.