Registered users receive a variety of benefits including the ability to customize email alerts, create favorite journals list, and save searches.
Please note that a BioOne web account does not automatically grant access to full-text content. An institutional or society member subscription is required to view non-Open Access content.
Contact helpdesk@bioone.org with any questions.
Wolf Canis lupus relationships with wild ungulates, domestic animals and humans were studied in an area of ca 800 km2 at the head of the Lovat River in northeastern Belarus during 1990–2000. The region was dominated by natural habitats (78%) consisting mainly of forests and bogs, but also lakes and rivers. The abundance of wild ungulates, such as moose Alces alces, wild boar Sus scrofa, and roe deer Capreolus capreolus, as censused by snow tracking and assessed by game wardens, declined 5 to 6-fold between 1990 and 1996, most probably due to uncontrolled exploitation and poaching. During 1997–2000, the numbers of ungulates began to recover. Wolves responded to the shortage of wild ungulates by a strong shift in feeding habits. When wild ungulates were numerous, wolf diet as studied by scat analysis was composed of wild ungulates (80–88% of consumed biomass), with small additions of medium- and small-sized wild animals (7–13%), mainly beaver Castor fiber and hare Lepus sp., and domestic animals (4–6%), mainly cattle. In the years when the recorded numbers of wild ungulates were at their lowest, wolves preyed on domestic animals (38% of biomass consumed), wild ungulates (32%), and medium- and small-sized wild prey (29%). Wolf damage to domestic animals (28 head of cattle and 247 dogs killed) and wolf-human interaction (100 observations of wolves in and near villages, including one attack by a rabid wolf on 11 people) were recorded in 14 villages. The rate of wolf predation on domestic animals and their appearances in villages increased exponentially with the declining biomass of wild ungulates and ceased again when wild ungulates began to recover; a one-year time lag in wolf response to changes in ungulate abundance was observed. The numbers of wolves as estimated by snow tracking and assessed by game wardens played a weaker role in shaping wolf-livestock and wolf-human interaction. The wolf population was strongly affected by hunting during the study. Wolves responded numerically with a 1 to 2-year time lag to the varying intensity of harvest by humans. Our study showed the role of the human factor in shaping wolf numbers and wolf-livestock interaction in eastern Europe. The three major components of this relationship were: 1) the manifold decline in wild ungulate abundance, which was most probably caused by uncontrolled exploitation by humans in the years of political transformation and economic regress, made wolves shift to predation on domestic animals; inevitably, wolves were frequently seen in the rural areas; 2) people interpreted the growing rates of wolf damage and appearances near the settlements as an effect of greatly increasing numbers of wolves, and demanded that authorities and hunters fight the ‘wolf plague’; 3) hunting impact on wolves increased and led to a marked reduction in wolf numbers and a decline in wolf-human conflicts. This scenario was most probably repeated in many areas of eastern Europe during 1990–2000, which was a decade of political and economical transformation. From a management perspective, we suggested that predation levels and wolf-human conflicts could be reduced not only by increased wolf harvest but also by enhancing the density and diversity of wild ungulates.
The relationships between fat depots and body fat content and between protein content and protein indices were examined in American marten Martes americana carcasses obtained from trappers in northeastern Ontario during the 1995/96 fur harvest season. Percent fat and percent protein did not differ significantly between sexes (t = 0.45 and 0.55, P = 0.66 and 0.58, respectively). Protein contents did not vary much among 42 individuals (range: 14–19%), and therefore we found no significant index of percent protein (0.01 < r < 0.23, P > 0.05, N = 42). In the development phase, percent fat (PFAT) was better predicted by six of the eight potential fat indices, and better predicted in females than in males (N = 17 and 18, respectively), but the omentum dry mass (ODM) performed best with both sexes (r2 = 0.69 and 0.80 males and females, respectively). During the test phase (N = 18 males, 22 females), estimated PFAT based on ODM (per sex) did not differ from observed percent fat in either males or in females (paired t = 0.01 and 1.28; P = 0.99 and 0.22, respectively). The models slightly overestimated the number of males and females of below average condition, which indicates that the models were conservative. The accuracy of the omentum dry mass fat depot appears adequate to detect changes of physical condition in harvested marten populations. The lack of variation in protein contents 1) indicates that most animals were near average protein level, possibly due to suitable habitat conditions and 2) prevented us from finding a protein index. We encourage the development of models where conditions (e.g. temperature regime, level of disturbance, carrying capacity) may be harsher for marten.
Pumas Puma concolor are stalking predators of large ungulates that usually cache their prey. We hypothesize that they require specific habitats to successfully stalk their prey and that they select cache sites based on some set of criteria. We tested these predictions during a study of predation by pumas on mule deer Odocoileus hemionus in south-central Idaho and northwestern Utah, USA. We found cache points of puma-killed deer in winter by locating radio-collared pumas. We then located where pumas had killed deer (kill points) by tracks in the snow. We classified these kill points relative to the dominant forest type and association with open, edge or forested areas. At a subset of the kill points and associated cache points, we also estimated tree and shrub density, tree diameter at breast height (dbh), shrub height and slope. Pumas killed deer more often than expected (P < 0.001) in juniper-pinyon habitat and in edge areas. Tree densities and dbh at cache points were significantly greater (P < 0.001) than at kill points or surrounding areas. We concluded that pumas relied on specific habitat characteristics to kill mule deer, and selected cache sites with older, larger trees.
The plane of nutrition in deer may affect body condition and lactation in hinds and calf growth both through long-term density-dependent effects and by shortterm abiotically originated falls in food supply. Our study examines the effect of low nutrient availability after calving on lactation in captive Iberian red deer Cervus elaphus hispanicus. Twelve hinds and their calves were allotted to a food restricted (50–60% daily energy requirements) or a control group just after calving. Hinds in the food-restricted group showed a greater body mass loss, produced less milk and yield of milk fat, protein and lactose, and a different lactation curve shape, which resulted in reduced calf growth. However, the time course of lactation variables appeared to show a compensatory response up to week 4: a greater milk fat content in low-nutrition hinds than in the control group appeared to compensate for lower milk production, as neither calf nor hind mass differed from the control group, and lactation variables in both groups showed a standard lactation pattern. In contrast, as milk fat content fell below that of the control group after week 4, the low nutrition plane overcame a standard lactation pattern and groups differed in most variables (e.g. calf and hind mass and percentage of calf growth). Our results appear to show that deer mobilise body reserves in lactation to maintain offspring growth under temporary reductions in food intake, which may be a strategy of securing investment in current offspring at the expense of reproducing the following season.
Sika deer Cervus nippon in Hokkaido, Japan, have recovered from a population bottleneck about 120 years ago and their distribution has expanded rapidly in the last three decades. We tracked 53 radio-collared female sika deer, and obtained 4,430 locations during the 25-month study period from April 1997 to April 1999. We examined the seasonal distribution of female sika deer in relation to spatial landscape features (snow depth, vegetation, bamboo grass and roads) with a logistic regression model using a geographic information system database. We presented a population-landscape scale evaluation of sika deer habitat for summer and winter within the telemetry study area (TSA) using resource selection functions. We then extrapolated the model to the rest of eastern Hokkaido to discuss the seasonal migration for an expanding population. Most radio-collared sika deer (71%) moved between high-elevation summer and low-elevation winter ranges, whereas some (29%) moved between low-elevation summer and similar or high-elevation winter ranges. During winter, sika deer selected middle elevation habitats (200–400 m a.s.l.) with both a relatively low snow depth and the presence of coniferous and mixed forests. On the other hand, sika deer were widely distributed regardless of elevation during summer, although they were further from roads and less often in agricultural lands. Within the TSA, the suitable habitat was very limited during winter compared with during summer. Although migration from summer to winter ranges may depend on the abundance and distribution of suitable winter habitat at a landscape scale, migration from winter to summer ranges could not be explained from this study. Our approach is useful for understanding the relationships among seasonal habitat selection, seasonal migration and the expansion of the population.
In this paper, we report two new simple field methods to assess changes in pectoral muscle mass in live moulting geese. In the first method, transverse chest profiles of Canada geese Branta canadensis and greylag geese Anser anser were recorded using soldering wire. This standard measure of the chest angle showed a highly significant relationship with actual pectoral muscle mass. Chest angle measures showed a highly significant polynomial correlation with an index of moult stage, i.e. length of the ninth primary (p9). This indicated an initial slight decline in pectoral muscle mass as p9 length increased, followed by an increase in muscle mass in preparation for regaining the ability to fly. In the second method, visual pectoral profile scores from 0 (thin pectoral muscles concave) to 3 (convex bulky) recorded at distances using telescope or binoculars also proved to be useful as a field measure of pectoral muscle mass in moulting geese. Hence, the first method provides a non-consumptive means of predicting pectoral muscle mass in moulting geese without the need to dissect birds, and the second method enables field prediction of muscle mass in moulting geese without resort to capture of birds.
Vegetation management practices currently used within transportation corridors are primarily aimed at minimising encroaching shrub and tree growth in order to increase driver visibility and road safety. Such practices create prime foraging habitat for ungulates such as moose Alces alces by inhibiting forest succession and maintaining early seral shrub communities. Increased foraging activity within the corridor increases the likelihood of encounters between moose and motorists. Moose-related vehicular collisions are costly in terms of material damage claims and have significant negative impacts on public safety and moose populations in many parts of their range. Although several countermeasures have been developed in an attempt to reduce the frequency of these collisions, few have proven effective and even fewer have taken into consideration possible links between roadside vegetation management, the quality of browse regenerating from cut vegetation, and how moose use browse within the transportation corridor. To better understand these relationships, I reviewed the literature on ungulate-related vehicular collisions in combination with literature on plant response to mechanical damage. Many authors recognise the need to reduce the attractiveness of vegetation growing within transportation corridors. To date, diversionary feeding, forage repellents, establishment of unpalatable species and elimination of roadside brush have been used. Unfortunately, such techniques are only semi-effective or are not cost-efficient when applied across the landscape. It has long been recognised that the ability of plants to regenerate following mechanical damage is influenced by the timing of damage. Current research suggests that the quality of regenerating plant tissues for herbivores also depends on when plants are cut. Plants cut in the middle of the growing season produce regrowth that is high in nutritional value for at least two winters following brush-cutting as compared to plants cut at other times of the year, and uncut controls. Because roadside brush is generally cut during mid-summer, possible links between the quality of regenerated browse and increases in ungulate-related vehicular collisions during the autumn and winter should be elucidated. Based on this review, I recommend cutting brush early in the growing season and emphasize the need for collaborative long-term research to properly address this issue.
The understanding of the demographic and ecological mechanisms of population regulation is central in applied ecology, in particular when it comes to managing harvested populations. We document the density dependence of the reproductive success in French grey partridge Perdix perdix populations. We used long-term data collected by the national network monitoring populations with a mere surveillance objective. We investigated a time series spanning 7–14 years for 85 replicate populations by a combined procedure of a regression of reproductive success against density for each population and a metaanalysis of the 85 regression slopes. We avoided two common statistical pitfalls by taking the autocorrelation in time series data into account and by using independent estimates of reproductive success and spring density. The relationship is statistically significant for 10% of the populations, and the meta-analysis of the 85 replicates displays a highly significant pattern (82.3% of the regression slopes being negative). Thus our results both support the existence of a density dependent reproductive success in the grey partridge and moderate the ubiquity of the phenomenon, despite a general trend. We tested whether density dependence occurred through competition or habitat heterogeneity by examining the relationship between the variability of per capita reproductive success and pair density. Our results support both alternative hypotheses depending upon the area of concern. In terms of population and habitat management our findings have implications for hunting interests. The best strategy to maximise the hunting quota when reproductive success is depressed with increased density recommends intermediate values of both pair density and reproductive success, which conciliates hunting interests and conservation objectives. To alleviate density dependence, habitat management should supply limited resources that are homogeneously distributed in space when density dependence operates through competition, and should improve habitat quality of the poorest patches when density dependence operates through habitat heterogeneity.
This article is only available to subscribers. It is not available for individual sale.
Access to the requested content is limited to institutions that have
purchased or subscribe to this BioOne eBook Collection. You are receiving
this notice because your organization may not have this eBook access.*
*Shibboleth/Open Athens users-please
sign in
to access your institution's subscriptions.
Additional information about institution subscriptions can be foundhere