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Context Supplemental feeding of large mammalian herbivores is a common management tool mainly aimed at promoting healthy populations and at increasing productivity and trophy sizes. Such management measure may indirectly affect herbivore effects on plant communities through altered foraging patterns. The quantification of the ecological effects of large herbivore management is important for designing holistic management and conservation programs. Aims Here we aimed at quantifying the ecological effects of supplemental feeding of Iberian red deer, Cervus elaphus hispanicus, on the composition of and on the browsing effects on Mediterranean woody plant community. Methods An experiment was set up in a hunting rangeland located in central Spain, where female deer were kept in enclosures with either exclusive access to natural forages or with additional ad libitum access to a nutritionally rich concentrate. The experiment also included a control area where deer were absent. Key results We observed significant differences in browsing impacts among the supplemented, non-supplemented and control areas, and such effect varied for the different plant species. Plant species which nutritional content complemented that of fodder were more highly consumed, for instance, Erica spp., which digestible fibre content is higher and N content lower than that of provided fodder. The presence of deer and the concentrate supplied, instead, did not influence the relative abundances of shrub species. Conclusions Artificial supplemental feeding provided to ungulates led to increased browsing on plant species which nutritional composition complemented that of the supplement provided. Implications So as to alleviate herbivory impact on all shrubs, we suggest that composition of supplemental feeding should adjust both to the natural forage availability and quality and to ungulate requirements across seasons.

Deer venison is increasingly valued as a natural meat. This study examines the three main sources of venison: farmed venison from New Zealand (NZ), the world's leading producer, and wild deer from Spain (SP), the second largest producer, which mainly supplies venison from traditional autumn–winter driven hunts (monteria), involving packs of dogs, and a smaller proportion culled through summer selective stalking. Meat from NZ contained more protein, lower shear force and lower n-6/n-3 ratio (P < 0.01). Spanish meat had a greater content of total, essential and non-essential amino acids (P < 0.01). Meat from deer culled in winter had lower intramuscular fat and saturated fatty acids (FA) but higher polyunsaturated FA (P < 0.01) and pH (P < 0.001) than meat from summer stalked deer. Therefore, venison presents differences by country of origin for composition, FA and texture that are likely to affect its health characteristics. Anomalies observed in meat between the winter driven hunt and non-stressful summer stalking may be attributed to the level of death stress in the case of variables such as pH. However, the effect on fat and mineral composition seems to be seasonal, depending respectively on wild diet or cyclic osteoporosis in males. ; This work was supported by project no. SBPLY/19/180501/000115 supported this work (funded by Counselling of Education, Culture and Sports of Castilla-La Mancha) and by the Spanish Ministry of Economy (Ministerio de Economía, Industria y Competitividad) within the Estate program of Research, Innovation and Development oriented towards Challenges of Society, and co-funded by the European Union (reference number RTC-2016-5327-2). This work was supported by the Spanish Ministry of Economy (Ministerio de Economía, Industria y Competitividad) within the Estate programme of Research, Innovation and Development oriented towards Challenges of Society, within the Framework Plan of Scientific, Technical Research, and Innovation 2013–2016 and co-funded by the European Union (reference number RTC-2016-5327-2). José M. Lorenzo is member of the MARCARNE network, funded by CYTED (ref. 116RT0503). ; Peer reviewed

In press. ; Crimean-Congo haemorrhagic fever virus (CCHFV) continues to cause new human cases in Iberia while its spatial distribution and ecological determinants remain unknown. The virus remains active in a silent tick-animal cycle to which animals contribute maintaining the tick populations and the virus itself. Wild ungulates, in particular red deer, are essential hosts for Hyalomma ticks in Iberia, which are the principal competent vector of CCHFV. Red deer could be an excellent model to understand the ecological determinants of CCHFV as well as to predict infection risks for humans because it is large, gregarious, abundant and the principal host for Hyalomma lusitanicum. We designed a cross-sectional study, analysed the presence of CCHFV antibodies in 1444 deer from 82 populations, and statistically modelled exposure risk with host and environmental predictors. The best-fitted statistical model was projected for peninsular Spain to map infection risks. Fifty out of 82 deer populations were seropositive, with individual population prevalence as high as 88%. The highest prevalence of exposure to CCHFV occurred in the southwest of the Iberian Peninsula. Climate and ungulate abundance were the most influential predictors of the risk of exposure to the virus. The highest risk regions were those where H. lusitanicum is most abundant. Eight of the nine primary human cases occurred in or bordering these regions, demonstrating that the model predicts human infection risk accurately. A recent human case of CCHF occurred in northwestern Spain, a region that the model predicted as low risk, pointing out that it needs improvement to capture all determinants of the CCHFV infection risk. In this study, we have been able to identify the main ecological determinants of CCHFV, and we have also managed to create an accurate model to assess the risk of CCHFV infection. ; This study has been funded by the Spanish Ministry for the Science and Innovation (MCI) through projects CGL2017-89866-R & E-RTA2015-0002-C02-02, and by the Regional Government of Castilla-La Mancha and the European Social Fund (ESF) through project SBPLY/19/180501/000321. RC-M, LC-M, SJ-R and JM-G would like to thank the MCI, ESF and the University of Castilla-La Mancha for their support through contracts PRE2018-083801, PEJ2018-003155-A, 2018/12504 and BES-2015-072206, respectively. BC was supported by FCT-Fundação para a Ciência e Tecnologia (2020.04872.BD). DG-B would like to thank MCI and Instituto de Salud Carlos III (CD19CIII/00011) for funding him. ; Peer reviewed