Sympatric Red Deer Research Articles

Winter foraging of sympatric red deer and sika deer in northeast China: diet composition, forage selection, bite diameter and browse intensity

ABSTRACT Red deer (Cervus elaphus) and sika deer (C. nippon) are sympatric in certain regions in northeast China, and may have different strategies for obtaining food resources. We studied winter forage selection of sympatric red and sika deer based on their bite diameter and browse intensity in northeast China. The principal winter food items of red and sika deer were Euonymus spp. and Acer spp., and both deer showed strong selectivity for E. verrucosus, E. alatus and Populus davidiana (EI>0.85) in spite of their low availability. Red and sika deer exhibited varying bite diameters and browse intensity for different forage plant species between early and late winter. Overall, the interaction effect of season and deer species on bite diameter and browse intensity indicated that two sympatric deer used different foraging strategies to increase food intake. In late winter, sika deer may have tended to increase bite diameter to fulfill a relatively constant food intake and potential nutritional requirement, while red deer may have tended to increase browse intensity to maintain a higher forage intake. Moreover, the interaction effect of plant and deer species on bite diameter and browse intensity indicated that both deer species tend to change their bite diameter and browse intensity particularly on Euonymus spp. and Acer spp., while red and sika deer have a reversal interaction effect on coniferous browse. These patterns of forage selection in bite diameter and browse intensity of sympatric deer may reflect short-term foraging decisions of sympatric herbivores that share similar food resources.

Winter Diet Variation and Overlap of Sympatric Red Deer and Sika Deer in Northeast China

The red deer (Cervus elaphus) and sika deer (C. nippon) are two important and endangered herbivores in northeast China. It is unclear whether potential dietary competition exists between them when they are sympatric in winter. We used micro-histological analysis of faecal samples to determine diet composition and dietary overlap of the red deer and sika deer in northeast China. We found that red deer had a more diverse diet than sika deer, and consumed more shrubs throughout the winter. Euonymus spp. was the most stable and principal food item for both red and sika deers in winter, while the proportions of the three other major food species (Acer spp., Abies spp. and Pinus spp.) were significantly different between the deer species as well as between different winter periods. The proportions of coniferous browse of sika deer increased significantly from early to late winter (20.9 vs 45.4%), while for red deer they remained stable (18.3 vs 23.7%). Crude protein in the red and sika deer's diet was over 7.5% of dry matter in whole winter. Red and sika deer take different strategies to meet their requirements for crude protein. Red deer consumed in winter consistently more shrubs to obtain crude protein and to minimize the intake of tannins, whereas sika deer increased coniferous browse consumption in late winter to meet the crude protein requirement regardless of higher intake of tannin. Our results indicate a high degree of dietary overlap between red and sika deers (range 0.88–0.95), and suggest its further increase in late winter.

Anaplasma phagocytophilum variants in sympatric red deer (Cervus elaphus) and sheep in southern Norway

Infections by the ixodid tick-transmitted bacterial pathogen Anaplasma phagocytophilum are common in domestic ruminants and cervids in the coastal areas of southern Norway. Previous experimental work has shown that A. phagocytophilum strains recovered from red deer (Cervus elaphus) are infective in lambs, but epidemiological links between infections in red deer and sheep have yet to be established. To address this shortfall, the present study explores the genotypic relatedness between A. phagocytophilum strains infecting sympatric red deer and sheep. Blood from 32 lambs grazing on tick-infested pasture, and blood and tissues from 8 red deer shot in proximity to these pastures were collected during the summer and autumn of 2007. The presence of A. phagocytophilum in these samples was determined by PCR-based methods, and genotyping of detected strains was performed using comparative sequence analysis of 16S rDNA and msp4 fragments. A. phagocytophilum DNA was detected in 12 lambs and 7 red deer, 11 and 4 individuals of which 16S rDNA and msp4 sequence data were obtained from, respectively. A total of 9 genotypes were delineated, and only different individuals of the same host species were infected with indistinguishable A. phagocytophilum genotypes. Although 3 of the red deer-infecting genotypes belonged to a cluster of exclusively deer-associated strains phylogenetically remote from those commonly encountered in sheep, one red deer-infecting genotype, although unique, clustered tightly with genotypes associated with a wide range of hosts including sheep.

Contrasting migration tendencies of sympatric red deer and roe deer suggest multiple causes of migration in ungulates

Understanding the drivers of seasonal migration among large herbivores is crucial for management and conservation. The forage maturation hypothesis predicts migration even at low population density, due to the benefits of increased access to newly emergent, high quality forage. We provide the first study comparing migration tendency of the two most widely distributed deer species in Europe, roe deer (Capreolus capreolus) and red deer (Cervus elaphus). The study was conducted in an area with a low population density of both species. We found that 94% of the GPS‐collared red deer, but only 27% of the roe deer, migrated. This supports the forage maturation hypothesis in red deer only. Our study thus provides evidence of multiple causation of migration in ungulates, and is consistent with the hypothesis that the forage maturation hypothesis might be a more important driver for migration in grazers compared to browsers.

Comparative pathological and immunohistochemical features of sarcoptic mange in five sympatric wildlife species in Northern Spain

This study collects pathological information concerning sarcoptic mange in sympatric red deer, roe deer, chamois, wolf and red fox from Northern Spain, and discusses reported variations in the response from the different species against Sarcoptes scabiei. Wolf is the only studied species which shows prevalence of the hypersensitivity (alopecic) response to the detriment of the hyperkeratotic form, usually observed in ungulates and fox. The present work shows the use of immunohistochemistry as a valuable tool for the study and diagnosis of sarcoptic mange in those species whose immune response or stage of infestation limits the number of detectable mites, not an unusual difficulty faced when working with sarcoptic mange in wildlife species.

Seasonal and specific diet variations in sympatric red and fallow deer of southern Spain: a preliminary approach to feeding behaviour

We studied the diet composition and diet overlap in sympatric red deer (Cervus elaphus hispanicus) and fallow deer (Dama dama) throughout a whole year in order to determine variation due to season, species, sex and age class by analysing rumen contents samples of 81 red and 69 fallow deer shot monthly during 2008–09 in Sierra de Andújar Natural Park, southern Spain. We assessed diet similarity and possible inter- and intra-specific foraging competition. We found different foraging strategies for both species and sexes during constraint periods, and several theoretical considerations of specific interactions and behaviour are discussed with respect to the Mediterranean environment. In both species an annual diet dominated by grasses was recorded, peaking in spring. Browses were an important food resource at the end of winter and at the end of summer, and fruit more in autumn and winter. Red deer ingested a higher proportion of browse than fallow deer, which consumed more acorns and for a longer time showed a better ability to compensate for nutritional constraint periods. An overall decline in diet similarity in summer and at the end of winter led us to assume that exploitative competition between red and fallow deer and even between sexes was probable. Red deer females showed low diet similarity to other deer, while there was a great diet overlap between red deer males and fallow deer females at the end of summer. Differences detected between both two species and sexes do not always support predictions deriving from specific body size and morpho-physiological characteristics, but can probably be explained as a consequence of different metabolic demands. The relationship between plant nutritional attributes and food selection according to reproductive or physiological status and seasonal demands for both sexes and species should be researched in order to perform a better assessment of deer feeding behaviour.

Seasonal variation in diet composition and similarity of sympatric red deer Cervus elaphus and roe deer Capreolus capreolus

Use of food resources by herbivores depends on intrinsic constraints, essentially body size and morpho-physiological characteristics, which determine the range of foods they tolerate and environmental constraints, such as seasonality and interspecific interactions, which determine the availability of resources. We analysed a collection of rumen contents samples from sympatric populations of red deer Cervus elaphus and roe deer Capreolus capreolus and tested several theoretical predictions relating to the impact of intrinsic and environmental constraints on diet composition, diversity and similarity. Red deer consumed more slowly digestible, fibrous forage than roe deer and had a more diverse diet throughout the year, which supports predictions deriving from specific body size and morpho-physiological characteristics. In conformity with the optimal foraging theory, both species consumed more slowly digestible forage in times of low food availability (i.e. during winter) than during the rest of the year. An increase in diet similarity in winter, along with predictions from the theory on competitive interaction processes, led us to assume that food resources were not limiting and that exploitative competition between red and roe deer was unlikely in our study area. We underline the importance of studies of the use of food resources by sympatric herbivores in answering applied ecological questions at the local scale, and we suggest that the Euclidean geometrical approach we used is particularly well suited for the analysis of resource matrices, a common end-product of long-term field data gathering on the feeding habits of animals.

ABOMASAL PARASITES IN WILD SYMPATRIC CERVIDS, RED DEER, CERVUS ELAPHUS AND FALLOW DEER, DAMA DAMA, FROM THREE LOCALITIES ACROSS CENTRAL AND WESTERN SPAIN: RELATIONSHIP TO HOST DENSITY AND PARK MANAGEMENT

A survey of abomasal parasites in cervids from Central Spain was conducted at 3 sites, Quintos de Mora (Toledo), Maluéñez de Arriba (Cáceres), and La Herguijuela (Cáceres). Commonly occurring helminths belonged to 3 polymorphic species of the Ostertagiinae: Spiculopteragia asymmetricalS. quadrispiculata, Ostertagia leptospicularis/O. kolchida, and O. drozdzi/O. ryjikovi. Trichostrongylus axei was found in very few cases. Ostertagia drozdzi/O. ryjikovi and the minor male morphotype, S. quadrispiculata, are reported for the first time in red deer from Spain. The 3 ostertagiine species are also reported for the first time in fallow deer from Spain. These 3 species of Ostertagiinae are primarily parasites of cervids, and nematode species characteristic of domestic ruminants were not present. Prevalence of infection by gastrointestinal parasites in cervids was high, ranging from 97.5 to 100%, across the 3 areas sampled. Mean intensity of infection and abundance showed a positive relationship to the population density of red deer. Helminth burdens were higher in fallow deer than in the sympatric red deer and may reflect the gregarious social structure and different foraging patterns of fallow deer.