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Feeding of wild Asian elephants at the Udawalawe National Park perimeter electric fence by the general public is longstanding. We monitored the elephants and feeding activities, and conducted questionnaire surveys of stakeholders. Over 50 individual adult male elephants engaged in the activity. The exclusive male presence was consistent with a high-risk high-gain male strategy. The elephants were mostly offered fruits and vegetables. Over a thousand people a day watched and fed the elephants. Most people bought food for elephants from roadside stalls and vendors had significantly more sales if elephants were present. The feeding of elephants brought significant economic benefit to communities bordering the park. We found the impacts of feeding on the elephants and environment to be largely neutral. Impacts on people and conservation were mainly positive. Actions taken by authorities to stop the feeding have targeted the elephants and resulted in the decrease of feeding but not its elimination. Managing the activity instead would help increase economic benefits and ensure safe interaction between people and elephants. Such management, by directly benefitting local communities, could make them partners in the conservation process and form the basis of an effective outreach program.

Ruminants are classified into three groups, according to their feeding behaviour: browsers, intermediate feeders and grazers. Corresponding to their dietary preferences, multiple morphological and physiological adaptations have been described, resulting in another classification: ‘moose-type’ and ‘cattle-type’ ruminants. Digesta retention patterns in the gastrointestinal tract (GIT) and reticulorumen (RR) are considered major criteria to distinguish these types, as cattle-type ruminants show shorter retention of fluids (measured by a solute marker) than of particles, while in moose-type ruminants, both are retained for more similar periods. To what extent these digestive types are specific to phylogenetic lineages is still unclear. We measured mean retention times (MRTs) of solutes and particles (2 and 20 mm) in the strictest grazing cervid: the Pere David’s deer (Elaphurus davidianus; n = 5; body mass = 155.0 ± 14.5 kg). The MRTs of solutes, small and large particles in the GIT were 34 ± 4, 60 ± 7 and 69 ± 9 h, respectively. The ratio of the MRT of small particles versus solutes in the RR was 2.0 ± 0.1, similar to other cattle-type ruminants. The results confirm the hypothesis that Pere David’s deer can be classified as cattle-type ruminants, corresponding to both dietary preferences and previously described morphological traits. The results complement previous findings, showing that both cattle-type and moose-type physiologies are found among bovids as well as cervids, indicating that these digestion types can be considered convergent adaptations.

Conventional concepts about trophic niches in mammals are often linked to adaptations of digestive physiology, and so carnivory by herbivorous animals is often considered a physiological impossibility. However, numerous reports on events of carnivory in herbivores without apparent harmful consequences exist. Here, we report the habitual daily consumption of animal prey (day-old chicks and rodents) by two rabbits kept in a mixed-species exhibit with raptors over a period of 9 months. While not requiring a change of the classification of rabbits as strict herbivores, anecdotes like this one suggest that some trophic niches might be better explained by other factors than digestive physiology, such as ecological opportunity, behavioural adaptations and biomechanical limits to ingestion.

In an analysis of a microsatellite locus (OLADRB1) linked to the MHC DRB1 gene of Iberian and Alpine ibex (Capra pyrenaica and Carpa ibex), we detected strong linkage disequilibrium between both loci. The allele length polymorphism at OLADRB1 was unambiguously linked to a particular DRB1 allele. This allowed us to develop a DRB- STR matching method for both ibex species. Validation of the DRB-STR matching method was performed in 160 Iberian ibex from Spain and 98 Alpine ibex from Switzerland and Italy. This simple and relatively inexpensive protocol may find wide applications in a variety of research areas (e.g., mate choice, pathogen-driven selection) and in the biological conservation and management of the Western European ibex populations

Ruminants are characterised by two different types of reticulorumen (RR) physiology. ‘Cattle-type’ ruminants have, amongst other features such as RR contents stratification and a heterogenous intraruminal papillation, a distinct difference between the mean retention time (MRT) of small particles and fluids (the ratio is called the selectivity factor, SF). ‘Moose-type’ ruminants have RR contents that are less stratified, a more homogenous intraruminal papillation and low SFs, indicating less difference in the MRT of small particles and fluids. To date, physiological data indicating a ‘moose-type’ physiology have only been measured in giraffids and Odocoilean cervids, raising the question whether it is limited to these taxonomic groups only. Here, we measured MRTs of fluids and particles in five duikers (Bovidae, Cephalophinae) from three species (Sylvicapra grimmia, Cephalophus monticola and Cephalophus sylvicultor) and found SFs in the RR of 1.27 ± 0.18—well within the range of these other browsers. These results are the first physiological indication that a ‘moose-type’ physiology may also occur in bovid species and thus might represent a true convergent adaptation.

Age determination of animals by measuring the weight of their eye lenses is a widely used method in wildlife biology. In general, it is recommended to prepare lenses immediately after trapping to avoid errors in the age estimation due to decomposition of lens tissue. However, in many field studies, large numbers of animals need to be trapped over long periods of time in huge areas and by many different field workers. Therefore, the immediate preparation of eye lenses imposes a considerable logistic constraint that could be avoided by prior freezing of trapped animals. To assess the impact of freezing, weights of lens of frozen and unfrozen eyes of 114 Arvicola terrestris were compared pair wise. The frozen lenses weighed at average 3.3% (95% CI: 2.4-4.1%) more than the unfrozen ones from the same animals. Freezing time, weight of lenses and mean temperature of the trapping day as an indicator of decomposition speed did not affect the freezing-induced weight increase. Age estimates based on weights of unfrozen lenses varied between 24 and 445 days. Estimates based on frozen lenses were systematically higher. Apply- ing a constant correction factor of 1.033 −1 for the weight of frozen lenses corrects this overestimation of age. We conclude that age determination with frozen lenses of small rodents can yield valid age estimates if a correction factor for freezing is applied. Thus, age determination can be organised much more efficiently in field studies, which is highly advantageous for many ecological, agricultural and epidemiological research projects.