Native Red Deer Cervus Elaphus Research Articles

Population dynamics in a guild of four Mediterranean ungulates: density‐dependence, environmental effects and inter‐specific interactions

Population fluctuations in ungulates are driven by both intrinsic and extrinsic factors. Available information, however, mainly refers to arctic, temperate and African ungulate populations, while the dynamics of Mediterranean species, exposed to a milder climate, is known to a much lesser extent. Here we studied the population dynamics of four wild ungulate species in the Castelporziano Preserve near Rome, Italy, as obtained from detailed bag counts from hunting drives during the period 1878–1986: the Italian roe deer Capreolus capreolus italicus, the Maremma wild boar Sus scrofa majori (both endemic to Italy), the native red deer Cervus elaphus, and the alien fallow deer Dama dama. We also considered the effects of the presence of another alien ungulate, the nilgai Boselaphus tragocamelus.This ungulate community experienced an accidental ‘removal experiment’ when, during World War II, red deer and nilgai were exterminated. This event and the length of the time series allowed us to test two main hypotheses: 1) that the complexity level of the ungulate community affects the strength of intra‐ and inter‐specific competition; and 2) that in Mediterranean environments intra‐ and inter‐specific interactions are stronger than climate forcing. Statistical methods ranged from state‐space‐modelling, GLM analysis and structural equation models.The results indicated that direct intra‐specific density dependence played a relevant role for all species, and was stronger after the removal. A complex pattern of species interactions was however revealed; fallow deer had a negative effect on roe deer population, while roe deer had an apparent positive effect on red deer and wild boar, possibly mediated by environmental factors. Nilgai appeared to facilitate all deer species. The results of the analysis also confirmed that at present climate appears to play a minor role with respect to density dependence; however, the increasing aridity of the Mediterranean area could change this picture in coming decades.

Phenotypic correlates of hybridisation between red and sika deer (genus Cervus)

1. Hybridisation with an invasive species has the potential to alter the phenotype and hence the ecology of a native counterpart. 2. Here data from populations of native red deer Cervus elaphus and invasive sika deer Cervus nippon in Scotland is used to assess the extent to which hybridisation between them is causing phenotypic change. This is done by regression of phenotypic traits against genetic hybrid scores. 3. Hybridisation is causing increases in the body weight of sika-like deer and decreases in the body weight of red-like females. Hybridisation is causing increases in jaw length and increases in incisor arcade breadth in sika-like females. Hybridisation is also causing decreases in incisor arcade breadth in red-like females. 4. There is currently no evidence that hybridisation is causing changes in the kidney fat weight or pregnancy rates of either population. 5. Increased phenotypic similarity between the two species is likely to lead to further hybridisation. The ecological consequences of this are difficult to predict.

Allozyme variation in native red deer Cervus elaphus of Mesola Wood, northern Italy: implications for conservation

Screening of 43 protein loci was used to evaluate the level of genetic variability in 42 red deer Cervus elaphus Linnaeus, 1758 from Mesola Wood, the only native population presently occurring in peninsular Italy.