We examined the long-term effects (28 years) of habitat loss and phenotype-based selective harvest on body mass, horn size, and horn shape of mouflon (Ovis gmelini musimon) in southern France. This population has experienced habitat deterioration (loss of 50.8% of open area) since its introduction in 1956 and unrestricted selective hunting of the largest horned males since 1973. Both processes are predicted to lead to a decrease in phenotype quality by decreasing habitat quality and by reducing the reproductive contribution of individuals carrying traits that are targeted by hunters. Body mass and body size of both sexes and horn measurements of males markedly decreased (by 3.4-38.3%) in all age classes from the 1970s. Lamb body mass varied in relation to the spatiotemporal variation of habitat closure within the hunting-free reserve, suggesting that habitat closure explains part of these changes. However, the fact that there was no significant spatial variation in body mass in the early part of the study, when a decline in phenotypic quality already had occurred, provided support for the influence of selective harvesting. We also found that the allometric relationship between horn breadth and horn length changed over the study period. For a given horn length, horn breadth was lower during the second part of the study. This result, as well as changes in horn curve diameter, supports the interpretation that selective harvesting of males based on their horn configuration had evolutionary consequences for horn shape, since this phenotypic trait is less likely to be affected by changes in habitat characteristics. Moreover, males required more time (approximately four years) to develop a desirable trophy, suggesting that trophy hunting favors the reproductive contribution of animals with slow-growing horns. Managers should exploit hunters' desire for trophy males to finance management strategies which ensure a balance between the population and its environment. However, for long-term sustainable exploitation, harvest strategy should also ensure that selectively targeted males are allowed to contribute genetically to the next generations.

The mouflon population of Caroux-Espinouse, southern France, inhabits a highly seasonal area with dry summers. We monitored summer lamb survival during a severe drought in 2003, from early June to late August. The survival of 35 radio-tagged lambs over nine two-week periods was strongly affected by the timing of rainfall. Survival depended on the amount of rainfall recorded at a given 14 day period and in the previous 14-21 day period. Survival was not influenced by the exceptionally high mean daily temperature recorded during some periods. Male lamb survival (0.68) tended to be less than female survival (0.81), although not signif icantly, possibly because of a low sample size. The high lamb mortality (25.7%) recorded during a four-month period is much higher than previous estimates of f irst-year mortality (less than 10%). We recommend accounting for climatic variation in summer when studying the population dynamics of ungulates.

Although many mouflon Ovis gmelini musimon populations have been introduced to continental southern and central Europe, little is known about their reproductive output. Based on post-mortem analysis of 344 harvested females, the variation in reproductive performance was investigated in three wild populations: two located in the French Alps and one in the south of France. Examination of tracts indicated a high pregnancy rate (> 80%) for females ≥ 1.5 years old. We found that a significant proportion of female lambs were pregnant in the Alps, c. 1 year earlier than generally reported for first reproduction in the mouflon, whereas female lambs did not conceive in the southern France population. Pregnant female lambs and yearling females always bore a single foetus. Among pregnant females ≥ 1.5 years old, twinning occurred less often in southern France (2.5%) than in the Alps (10.8% and 20.7%). The data required to relate body mass and reproductive output of ewes at individual level were lacking, but female lamb-ewe body mass ratio was used to test that the population with high reproductive output should have the highest ratio. As expected, the index was higher in the Alps than in southern France, suggesting between-population differences in the quality of the local environment. Differences in growth pattern and birth timing of lambs, or different tactics of maternal care could also have influenced the female lamb-ewe body mass ratio. Crossings between wild and domestic sheep during the recent history of these populations and differences in environmental conditions might have interplayed to shape age at first reproduction and twinning rates.

No abstract

In prey species, vigilance is an important part of the decision making process related to predation risk effects. Therefore, understanding the mechanisms shaping vigilance behavior provides relevant insights on factors influencing individual fitness. We investigated the role of extrinsic and intrinsic factors on vigilance behavior in Mediterranean mouflon (Ovis gmelini musimon×Ovis sp.) in a study site spatially and temporally contrasted in human pressures. Both sexes were less vigilant in the wildlife reserve compared to surrounding unprotected areas, except for males during the hunting period. During this period, males tended to be less strictly restricted to the reserve than females what might lead to a pervasive effect of hunting within the protected area, resulting in an increase in male vigilance. It might also be a rutting effect that did not occur in unprotected areas because males vigilance was already maximal in response to human disturbances. In both sexes, yearlings were less vigilant than adults, probably because they traded off vigilance for learning and energy acquisition and/or because they relied on adult experience present in the group. Similarly, non-reproductive females benefited of the vigilance effort provided by reproductive females when belonging to the same group. However, in the absence of reproductive females, non-reproductive females were as vigilant as reproductive females. Increasing group size was only found to reduce vigilance in females (up to 17.5%), not in males. We also showed sex-specific responses to habitat characteristics. Females increased their vigilance when habitat visibility decreased (up to 13.8%) whereas males increased their vigilance when feeding on low quality sites, i.e., when concomitant increase in chewing time can be devoted to vigilance with limited costs. Our global approach was able to disentangle the sex-specific sources of variation in mouflon vigilance and stressed the importance of reserves in managing and conserving wild sheep populations.