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In 2014 Haemaphysalis punctata was found in several locations on the mainland of the Netherlands for the first time since 1897. In the same areas Dermacentor reticulatus and Ixodes ricinus were found. Haemaphysalis punctata and D. reticulatus were tested for presence of Babesia spp. and Rickettsia spp. by PCR. Babesia spp. and spotted fever Rickettsiae were not detected in any of the collected H. punctata , while several D. reticulatus (6%) collected from the same areas were found to be positive for R. raoultii , a causative agent of tick-borne lymphadenopathy. We discuss the role of free-ranging domestic animals in maintaining H. punctata and D. reticulatus populations in dune areas in the Netherlands. [ABSTRACT FROM AUTHOR]

• The density of questing I. ricinus adults, but not nymphs, is lower in forested areas with cattle grazing. • The densities of ticks infected with Anaplasma phagocytophilum is lower in forested areas with cattle grazing. • Cattle grazing had no effect on the density of ticks infected with Lyme spirochetes, B. miyamotoi , and Babesia venatorum. Cattle grazing has been suggested to reduce the risk for Lyme borreliosis by decreasing the density of questing Ixodes ricinus infected with Borrelia burgdorferi sensu lato. We tested the hypotheses that cattle grazing used in woodland management decreases the density of questing I. ricinus , and that it decreases the nympal infection prevalence of B. burgdorferi sensu lato. We further expected the nympal infection prevalence of tick-borne pathogens that utilize cattle as amplifying hosts, namely Anaplasma phagocytophilum, and Babesia sensu stricto, to increase. To test these hypotheses, we compared the densities of questing I. ricinus between twenty pairs of plots in grazed and ungrazed forest areas. The density of I. ricinus adults, but not nymphs, was lower in areas grazed by cattle than in ungrazed areas. Nymphs were tested for the presence of Borrelia burgdorferi s.l., Borrelia miyamotoi, Anaplasma phagocytophilum, and Babesia s.s. DNA from twelve paired areas. Anaplasma phagocytophilum and Babesia s.s. from qPCR-positive tick lysates were identified further to the ecotype and species level, respectively, by DNA sequencing. The infection prevalence of A. phagocytophilum was lower, and infection prevalence of Babesia s.s., identified as Babesia venatorum , was higher in grazed areas. In contrast, infection prevalence with B. burgdorferi s.l. or B. miyamotoi did not differ between grazed and ungrazed areas. As a consequence, conventional cattle grazing in forested areas had no effect on the densities of questing nymphs infected with B. burgdorferi s.l. and B. miyamotoi. Similarly, we found no effect of cattle grazing on the density of infected nymphs with B. venatorum. The marked difference in the densities of questing nymphs infected with A. phagocytophilum could potentially be explained by the presence of a higher density of roe deer (Capreolus capreolus) in ungrazed areas, as the majority of typed A. phagocytophilum from ungrazed areas were the non-zoonotic ecotype II, which is associated with roe deer. [ABSTRACT FROM AUTHOR]

Elephant inhabiting arid and semi-arid savannas often experience periods of drought, which, if prolonged, may cause mortality. During dry periods, elephant aggregate around water sources and deplete local forage availability. However, the relationships between adult elephant mortality and both high local elephant density and forage availability close to water during dry periods remain unexplored. We hypothesized that elephant mortality is higher: a) when dry periods are longer, b) closer to water points, and c) in areas with higher local elephant density. Using nine years of elephant carcass data from Tsavo Conservation Area in Kenya, we analysed the probability of adult elephant mortality using maximum entropy modelling (MaxEnt). We found that elephant carcasses were aggregated and elephant mortality was negatively correlated with four months cumulative precipitation prior to death (which contributed 41% to the model), Normalised Difference Vegetation Index (NDVI) (19%) and distance to water (6%), while local elephant density (19%) showed a positive correlation. Three seasons (long dry, short dry and short wet seasons) showed high probability of elephant mortality, whereas low probability was found during long wet seasons. Our results strongly suggest that elephants starve to death in prolonged drought. Artificial water holes may lead to lower mortality, but also to larger populations with subsequent high browsing pressure on the vegetation. Our results suggest that elephant populations in arid and semi-arid savannas appear to be regulated by drought-induced mortalities, which may be the best way of controlling elephant numbers without having to cull. [ABSTRACT FROM AUTHOR]

Abstract: Animal orientation relative to incident solar radiation allows an animal to effectively adjust the amount of radiant heat gained from an environment. Yet recent literature found ruminants to primarily orientate north/south and proposed magnetic alignment as the most parsimonious explanation. To test whether such northerly orientation has an energy advantage, we used heated cylindrical models to estimate energy costs of thermoregulation associated with north and east orientations of three species of African ruminants under cool winter conditions. Concurrent behavioural observations revealed that eland, blue wildebeest and impala did not preferentially orientate north/south during warm summer or cool winter conditions. Instead, all three species preferred to orientate perpendicular to incident solar radiation during winter and parallel to incident solar radiation during summer, throughout the day. On clear winter days with little wind, more than 60% of animal orientation preference could be accounted for by the energy savings associated with that orientation. Thus energy demands are likely to be the primary driver of animal orientation preferences. [Copyright &y& Elsevier]

Abstract: Savanna covers about two-thirds of Africa, with forage quantity and quality being important factors determining the distribution and density of wildlife and domestic stock. Testing hypotheses about the distribution of herbivores is hampered by the absence of reliable methods for measuring the variability of vegetation quality (e.g. biochemical composition) across the landscape. It is demonstrated that hyperspectral remote sensing fills this gap by revealing simultaneously the spatial variation of foliar nitrogen (crude protein) as well as the total amount of polyphenols, in grasses and trees. For the first time, the pattern of resources important for feeding preferences in herbivores (polyphenols and nitrogen) is mapped across an extensive landscape and the modeled foliar concentrations are shown to fit with ecological knowledge of the area. We explain how estimates of nitrogen (crude protein) and polyphenols may be scaled up from point-based observations to reveal their spatial pattern, and how the variation in forage quality can influence the management of savannas, including farms, communal grazing areas, and conservation areas. It provides a glimpse of the choices herbivores must face in selecting food resources of different qualities. [Copyright &y& Elsevier]