Interactions and associations between age and sex classes in mouflon sheep (Ovis gmelini) during winter

The fact that sexual segregation can occur in wild ruminants independently of sex-related differences in habitat use suggests that it results at least partly from social mechanisms. One of the simplest mechanisms which can be hypothesised is that individuals avoid the congener classes which frequently try to interact with them (be these interactions 'agonistic' or 'sexual', since courtship behaviour components typically induce withdrawal when performed outside the rut). The aim of the present study was to test, in mouflon sheep (Ovis gmelini), whether the age-sex classes which exchange frequent interactions on meeting occur rarely inside the same groups. Observations were made during winter, on a small population in Germany. Interactions were recorded at an attractive site where all age-sex classes met daily. Foot transects were conducted in parallel over the whole study area in order to determine group composition. As expected, adults of different sexes exchanged frequent interactions at the attractive site and were rarely found in the same groups under free-ranging conditions, while adult females, who interacted little with one another, were quite frequently associated. However, adult males simultaneously exhibited the highest rate of interaction at the attractive site and the highest frequency of association under free-ranging conditions. Unlike female-female and male-female pairs, in which interactions with a clear initiator and a clear recipient predominated, male-male pairs exchanged often spectacular but 'symmetrical' interactions (during which the two individuals behaved in the same way). The hypothesis that sexual segregation results from the avoidance of the congener classes which frequently engage interactions only holds for females. Adult rams interact frequently and seek companions with whom symmetrical interactions can be performed.     

Sex differences in relationships between habitat use and reproductive performance in Soay sheep (Ovis aries)

The role of habitat use in generating individual variation in fitness has rarely been examined empirically in natural populations of long‐lived mammals, particularly for both sexes simultaneously. This is the case despite the increase in studies attempting to understand evolutionary change in such populations. Using data from the St. Kilda Soay sheep population, we quantified the association between lifetime reproductive performance (lifetime breeding and reproductive success) and the proportion of the home range covered by a key grass species, H. lanatus, for 490 females and 304 males. Increased H. lanatus cover was associated only with increased female lifetime reproductive success, but increased lifetime breeding success for both sexes, arising through increased male longevity and increased female fecundity. This work suggests that improved understanding of the causes and consequences of fitness differences will likely require us to better account for habitat‐derived individual variation, and to do so for the sexes appropriately.     

Agonistic and proximity patterns in enclosed mouflon (Ovis gmelini) ewes in relation to age, reproductive status and kinship

Agonistic and proximity patterns of mouflon sheep (Ovis gmelini) were studied in a group of enclosed females during two lambing periods. A non-random linear-tending hierarchy almost stable over the 2-years was found. Age was correlated to social rank and to the distribution of agonistic acts by females. The rank of the yearling females was linked to the rank of their mothers. The age of the animal and the degree of relatedness with its congeners appeared as main determinants of the proximity patterns of ewes. Strong associations between closely related females (especially mothers and daughters), brought out the existence of a familial structure in mouflon. Otherwise, we found a strong inter-attraction between yearlings, which received a large number of aggressions from older females. That revealed peer grouping superimposed on familial structures. Age also seemed to influence ‘sociality’ of females, older females tending to associate less with conspecifics than younger ones.     

Ranging patterns and habitat use of Sulawesi Tonkean macaques (Macaca tonkeana) in a human-modified habitat

The goal of this study was to investigate the ecological flexibility of Tonkean macaques (Macaca tonkeana) by examining how they respond to human-induced habitat alteration. To do so, I observed movement patterns, forest strata use, microhabitat use, and home range use in two groups that occupied habitats with different levels of human alteration and habitat quality in Lore Lindu National Park, Sulawesi, Indonesia. The group occupying the heavily altered habitat (Anca) spent a significantly greater proportion of time traveling on the ground than the group in minimally altered habitat (CH), and significantly more time than expected in microhabitats within their range that were characterized by greater alteration (e.g., agroforestry areas). There was no significant difference between the two groups in daily path length, despite differences in group size. The Anca group exhibited a greater home range area per individual than the CH group, and utilized a more limited area within their home range with greater intensity, relative to the CH group. Tonkean macaques therefore show considerable flexibility in response to anthropogenic disturbance by adjusting their use of forest strata to facilitate travel and increase foraging opportunities and by intensively using particular areas within their home range where known resources are present and predictably available.     

Male harassment drives females to alter habitat use and leads to segregation of the sexes

Sexual conflict is ubiquitous across taxa. It often results in male harassment of females for mating opportunities that are costly for females, in some cases reducing reproductive success and increasing mortality. One strategy that females may employ to avoid sexual harassment is to segregate spatially from males. In fact, we do find sexual segregation in habitat use in species that have high levels of sexual conflict; however, the role of sexual harassment in driving such segregation remains poorly understood. Here, we demonstrate experimentally in a population of wild Trinidadian guppies Poecilia reticulata that male sexual harassment drives females into habitats that they otherwise do not prefer to occupy. In support of the social factors hypothesis for sexual segregation, which states that social factors such as harassment drive sexual segregation, this female behaviour leads to segregation of the sexes. In the presence of males, females actively select areas of high predation risk, but low male presence, and thus trade off increased predation risk against reduced sexual harassment.     

Influence of age on the relationship between annual changes in horn growth rate and prolactin secretion in the European mouflon (Ovis gmelini musimon)

Annual variations in the growth of horns, and their correlation with seasonal changes of testicular size, and prolactin (PRL) and melatonin secretion were monitored in six pubertal mouflon rams living in their original latitude (40 degrees N). Mouflons born and maintained under captive conditions were classified in two age classes: sub-adult (2 years; n=3) and adult (> or =3 years; n=3). The rate of horn growth was greater (P <0.001) in sub-adult than in adult mouflon rams. Horn growth was influenced by season in both adult and sub-adult mouflons (P <0.05) with largest monthly growth occurring in spring and summer. Seasonal variations of plasma PRL concentrations were correlated with horn growth in adult, but not in sub-adult mouflon rams. The rate of horn growth was inversely correlated with testicular size (r=-0.5, P=0.07). Seasonal changes in the amplitude of the daily melatonin rhythm in solstices and equinoxes were observed, which were not correlated with variations in the rate of horn growth. These results provide support for a possible role of PRL in the control of growth of horns in the adult mouflon.     

Maternal condition and offspring sex ratio in polygynous ungulates: a case study of bighorn sheep

The Trivers and Willard model (TWM) predicts that for sexuallydimorphic polygynous mammals, mothers able to provide a highlevel of care should bias offspring sex ratio in favor of sons.Contradictory results of empirical studies, however, suggestthat selective pressures for adaptive offspring sex ratio varywith species and environmental conditions. We report the resultsof a 29-year study of marked bighorn sheep (Ovis canadensis)in a population that underwent wide changes in density and wheremost females were weighed each year. Lamb sex ratio was independentof absolute ewe mass and yearly deviations from individual orpopulation average mass, but there was a nonsignificant trendtowards fewer males being born at high population density. Bighornsheep satisfy all the assumptions of the TWM but not its prediction:lamb sex ratio is independent of maternal ability to providecare. Recent hypotheses to explain the lack of relationshipbetween maternal condition and offspring sex in ungulates areunlikely to apply to bighorn sheep. We suggest that the TWMmay only apply when social rank strongly affects the abilityto provide maternal care. Those circumstances are likely tooccur for only a few species and within a narrow range of environmentalconditions.     

贺兰山岩羊（Pseudois nayaur）夏季取食和卧息生境选择

采用直接观察法和痕迹检验法对贺兰山岩羊夏季取食和卧息生境选择进行研究.结果表明,夏季岩羊偏好的取食地位于海拔高度1 600～2 000 m的山地疏林草原带,地形为平滑起伏的坡、明显断裂的坡和悬崖,以灰榆和山杨为优势乔木或无树,乔木矮小稀疏且距离远,接近低矮但密度较大的灌木,食物较多,位于<30°和>35°半阴半阳坡的下坡位,接近水源,人为干扰距离500～1 000 m,距裸岩2～5 m,隐蔽级25%～75%;夏季岩羊偏好的卧息地具有位于海拔高度1 600～2 000 m和>3 000 m的山地疏林草原带及亚高山灌丛和草甸带,地形为明显断裂的坡和悬崖,以灰榆和山杨为优势乔木或无树,乔木和灌木均矮小稀疏且距离较远,食物较少,位于>35°阴坡的上坡位,接近水源,人为干扰距离远,接近裸岩,隐蔽程度低.岩羊的取食和卧息生境在乔木高度和距水源距离上差异不显著(P > 0.05),而其余生态因子均有显著差异(P < 0.05).与取食生境相比,岩羊选择的卧息生境具有乔木稀疏且距离较远、灌木较少、低矮且距离较远、食物丰富度低、坡度大、远离人为干扰、接近裸岩和隐蔽程度低的特征.逐步判别分析表明,食物丰富度、灌木高度、距水源距离、隐蔽级、灌木密度、灌木距离、乔木高度和乔木距离8个生态因子可以区分取食样方与任意样方,正确判别率为85.8%;而区分卧息样方与任意样方时,距水源距离、灌木高度、距裸岩距离、人为干扰距离、食物丰富度、灌木密度和灌木距离共7个生态因子发挥作用,正确判别率为89.1%.     

Activity budgets, habitat use and body size in two coexisting species of sand wasps (Microbembex: Sphecidae, Hymenoptera)

ABSTRACT. 1. Two superficially similar species of Microbembex, M.monodonta (Say) and M.cubana Bohart (Hymenoptera, Sphecidae, Nyssoninae), occur syntopically on Staniel Cay, a small Bahamian island (15 km²).
2. Nesting (female) and territorial (male) aggregations of M.cubana were smaller and more numerous than those of M.monodonta in the study site and on the island as a whole.
3. Both species had regular patterns of daily activities that required them to use a variety of microhabitats in the study area.
4. Males of both species defended territories from c. 09.00 to 12.00 hours EST (in May) and the left to feed on nectar until they retired to sleeping burrows, typically from 13.00 to 15.00 hours. Male M.monodonta were active longer each day and intermixed feeding and territorial defence more than did male M.cubana.
5. Females of both species were active for longer each day, from c. 08.30 to 15.30 hours, and intermixed their respective activities – hunting for provisions, feeding, and nest digging and maintenance – during each day more than did males. Female M.monodonta were active longer each day, rising earlier and retiring later, than female M.cubana.
6. In M.monodonta , females were larger (length, X =11.00 mm) than males (10.5 mm). In M.cubana , males were larger (11.1 mm) than females (10.4 mm). Although mean differences were small, they were highly significant ( F =22.42; P <10⁻⁴) for the species-sex interaction.
7. Differences in activity budgets, habitat use, and sexual size dimorphism appear to be related. A combination of factors, particularly thermal constraints, possible competition, and different mating systems, could explain these patterns.     

Molecular DNA identity of the mouflon of Cyprus (Ovis orientalis ophion,Bovidae): Near Eastern origin and divergence from Western Mediterranean conspecific populations

The mouflon population of Cyprus (Ovis orientalis ophion) comprises historically preserved feral descendants of sheep domesticated during the Neolithic. We determined genetic identity of this taxon in order to elucidate its systematic placement and enforce its protection. We used 12 loci of microsatellite DNA to infer genetic relationships between the Cypriot mouflon and either long-time isolated (Corsica, Sardinia) or recently introduced (central Italy) European mouflons (O. o. musimon). We also sequenced the mitochondrial DNA (mtDNA) Cytochrome-b gene to infer the origin of the Cypriot mouflon including many National Centre for Biotechnology Information (NCBI) entries of European and Near Eastern conspecifics. Microsatellites disclosed net divergence between Western Mediterranean and Cypriot mouflon. The latter was included in the highly heterogeneous Near Eastern O. orientalis mtDNA group, Iran representing the most credited region as the source for its ancient introduction to Cyprus. Both international and national legislation protect the mouflon of Cyprus as a wild taxon (O. o. ophion). However, the IUCN Red List of Threatened Species and NCBI include the Cypriot mouflon as subspecies of its respective domestic species, the sheep (O. aries). Unfortunately, people charged with crime against protected mouflon may benefit from such taxonomic inconsistency between legislation and databases, as the latter can frustrate molecular DNA forensic outcomes. Until a definitive light can be shed on Near Eastern O. orientalis systematics, we suggest that the Cypriot mouflon should be unvaryingly referred to as O. o. ophion in order not to impair conservation in the country where it resides.     

Mining activity and habitat use by mountain sheep (<Emphasis Type="Italic">Ovis canadensis</Emphasis>)

We studied mountain sheep in the vicinity of three high-wall limestone mines in San Bernardino County, CA, USA to evaluate factors that influenced habitat use and, specifically, to investigate the influence of mining activity on distribution of those specialized ungulates. We used aerial telemetry data to estimate a resource selection function by fitting a logistic regression model and then comparing environmental characteristics at observed sheep locations to those at random locations. Distribution of mountain sheep was most influenced by a fire in 1999 that resulted in an area they avoided. Mountain sheep used steeper slopes, areas of lower terrain roughness, higher elevations, and areas closer to escape terrain than were random points. In contrast, sheep avoided areas near roads (federal and state highways, local roads, and off-road vehicle trails) but used areas near hiking trails and a railway. Water sources had the smallest effect of the factors considered, with sheep being associated with areas further from water points than were random locations. The disturbed area associated with the mines had a moderate influence on distribution, with sheep being associated with areas closer to the mine than were random points. Mining activities can alter terrain features and vegetation structure or composition in a way that promotes occupancy by sheep if they create steep slopes and rugged terrain (escape terrain) or reduce vegetation density or height (i.e., improve visibility). Whether increased occupancy reflects a benefit depends on the demographic responses of those sheep to the resources and conditions available on mine sites; information about those responses remains lacking.     

Competition between red kangaroos (Macropus rufus) and sheep (Ovis aries) in the arid rangelands of Australia

Abstract Competition between red kangaroos and sheep in the more arid areas of Australia was examined by means of a large-scale manipulative experiment incorporating two replicates of each of three treatments: sheep-only, kangaroo-only and a sheepAangaroo mixture. The study was conducted over two years during which time pasture conditions varied markedly. Competition was intermittent, occurring only during a period of climatically related food depletion (semi-drought). At this time there was a large increase in kangaroo densities due to an influx of kangaroos from neighbouring areas. Competition reduced live-weight in sheep but had no significant impact on wool production. This effect was linked to diet selection. Competition caused red kangaroos to favour paddocks destocked of sheep but had no detectable effect on the condition of kangaroos.     

Habitat use and movements of plains zebra (Equus burchelli) in response to predation danger from lions

Prey species must adapt their behavior to avoid predation. Asa key prey item for lions (Panthera leo), plains zebras (Equusburchelli) were expected to respond to immediate threats posedby lions in their area. In addition, zebras were predicted toexhibit behavior tuned to reduce the potential for encounterswith lions, by modifying their movement patterns in the timesof day and habitats of greatest lion danger. We studied a populationof approximately 600 plains zebra living in Ol Pejeta Conservancy,Kenya. We found that zebra abundance on or near a grasslandpatch was lower if lions had also been observed on that patchduring the same day. Predation danger was highest in grasslandhabitat during the night, when lions were more active. Zebrasightings and global positioning system radio collar data indicatedthat zebras also reduced their use of grassland at night, insteadusing more woodland habitat. Zebras moved faster and took sharperturns in grassland at night. It is hypothesized that these moreerratic movements assist zebras in avoiding detection or captureby lions.     

Correlations between habitat use and body shape in a phrynosomatid lizard (Urosaurus ornatus): a population-level analysis

Recent ecomorphological studies have shown that the predicted correlations between morphology and ecology on broad taxonomic levels are often obscured when comparing more closely related groups. Among species, comparisons of lizards often indicate very little support for adaptive radiations into novel habitats. As few population level studies have been performed, we compared body, head and limb shape between four populations of Urosaurus ornatus living in structurally distinct habitats (cliffs, rocks, trees and boulders). Surprisingly, clear correlations between habitat use and body shape among populations were found, most of which were in good accordance with a priori biomechanical predictions (e.g. flat body and head for extreme climbers; long distal hindlimb segments for jumpers and runners; narrow body and long tail for tree dwelling lizards). This indicates that populations of Urosaurus ornatus are seemingly 'adapted' to the habitat they live in. However, quantification of performance and behaviour are needed to determine the adaptive nature of these observations.     

Seasonal home range dynamics and sex differences in habitat use in a threatened,coastal marsh bird

A comprehensive understanding of spatiotemporal ecology is needed to develop conservation strategies for declining species. The king rail (Rallus elegans) is a secretive marsh bird whose range historically extended across the eastern United States. Inland migratory populations have been greatly reduced with most remaining populations inhabiting the coastal margins. Our objectives were to determine the migratory status of breeding king rails on the mid‐Atlantic coast and to characterize home range size, seasonal patterns of movement, and habitat use. Using radiotelemetry, we tracked individual king rails among seasons, and established that at least a segment of this breeding population is resident. Mean (±SE) home range size was 19.8 ± 5.0 ha (95% kernel density) or 2.5 ± 0.9 (50% kernel density). We detected seasonal variation and sex differences in home range size and habitat use. In the nonbreeding season, resident male home ranges coincided essentially with their breeding territories. Overwintering males were more likely than females to be found in natural emergent marsh with a greater area of open water. Females tended to have larger home ranges than males during the nonbreeding season. We report for the first time the use of wooded natural marsh by overwintering females. Brood‐rearing king rails led their young considerable distances away from their nests (average maximum distance: ~600 ± 200 m) and used both wooded natural and impounded marsh. King rails moved between natural marsh and managed impoundments during all life stages, but the proximity of these habitat types particularly benefitted brood‐rearing parents seeking foraging areas with shallower water in proximity to cover. Our results demonstrate the importance of interspersion of habitat types to support resident breeders. Summer draining of impounded wetlands that are seasonally flooded for wintering waterfowl allows regrowth of vegetation and provides additional habitat at a critical time for wading birds.     

The dietary overlap between red kangaroos (Macropus rufus) and sheep (Ovis aries) in the arid rangelands of Australia

Abstract The interaction between red kangaroos and sheep in the more arid areas of Australia was examined by means of a large-scale manipulative experiment. The diets of red kangaroos and sheep grazing together and separately in large paddocks were studied to assess whether competition for food might influence diet selection in these species. Diets and the amount of intra- and interspecific dietary overlap varied in accordance with pasture conditions. At pasture biomasses ranging from 50 to 200 g m^?2 (dry weight [wt]), the diets of red kangaroos and sheep overlapped by 58–73%, with forbs and grasses being the major items in the diets of both species. The diets of both sheep and red kangaroos under different experimental regimes were similar. In dry times (pasture biomass 40–50 g m^?2 (dry wt) more shrubs were eaten by both species and the amount of dietary overlap tended to be lower (52–66%). The diets of kangaroos were similar between paddocks. However, in paddocks containing both species sheep consumed proportionately more chenopodaceous shrubs and fewer grasses than those in ‘kangaroo-free’ paddocks.     

Density,home range,seasonal movements and habitat use of the mountain pygmy‐possum Burramys parvus (Marsupialia: Burramyidae) at Mount Blue Cow,Kosciuszko National Park

A population of mountain pygmy‐possums Burramys parvus was studied at the Mount Blue Cow ski resort in Kosciuszko National Park between 1986 and 1989. Forty‐eight individuals were radiotracked during the snow‐free months and 21 individuals were tracked during winter over the 3 years of study. Trapping and radiotracking showed that the density, population structure, movements and home range sizes of B. parvus on Mount Blue Cow were strongly correlated with elevation and changed with the season. Female densities were greatest in habitats characterized by deep boulderfields, at high elevations with an abundance of Bogong moths. Males visited the areas where females were located to breed in November–December and then by February, the majority migrated to lower elevations or north and westerly aspects. Females that nested at lower elevations also visited high‐elevation habitats to access the high concentrations of Bogong moths, which were the main food source in summer. A high proportion of the juvenile males and some juvenile females dispersed to lower elevations in March and April. The resulting sexual segregation during autumn and winter may be a result of female aggression or scramble competition, but is also explainable by differences in energy requirements, seed availability and hibernation strategies between the sexes. The extraordinarily large nightly and seasonal movements between habitat patches of up to 2 km for females and 3 km for males, sexual segregation and the use of different hibernation sites have important implications for the management of this species. These include the need for movement and dispersal corridors and the conservation of boulder‐heath habitats outside the main boulderfields.