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1.
Jonathan C. Reynolds Chris Stoate Malcolm H. Brockless Nicholas J. Aebischer Stephen C. Tapper 《European Journal of Wildlife Research》2010,56(4):541-549
The brown hare Lepus europaeus is a valued game species but also a species of conservation concern owing to its severe decline in abundance on farmland
throughout Europe during the twentieth century. Changes in the farmland habitat and predation have both been cited as causative
factors. Their relative roles have been unclear, but most conservation action has focused on improving habitat. We analyse
data from a sequence of three unique studies (one experiment and two demonstrations) covering the period 1985–2006 in which
control of several common predator species was undertaken to increase densities of wild game on farmland in England. Across
the three studies, regression modelling of the proportional change in hare numbers between successive years showed that—after
site, year differences and harvesting were accounted for—predator control was a significant determinant of hare population
change. Where habitat improvement also took place, hares reached autumn densities that were exceptional for the UK and which
could sustain substantial harvests. When predation control was stopped, hare densities fell, even where habitat improvements
remained in place. This analysis demonstrates that even where farmland habitat is greatly improved, uncontrolled predation
prevents hares making full use of its carrying capacity. This helps explain the mixed—and at best modest—success of agri-environment
schemes in the UK and elsewhere in Europe to increase hare densities. Game-shooting estates, on which effective predator control
takes place, probably have a special significance within the landscape as source areas for brown hares. 相似文献
2.
Stéphanie C. Schai-Braun Darius Weber Klaus Hackländer 《European Journal of Wildlife Research》2013,59(3):387-397
The number of European brown hares (Lepus europaeus) has been declining throughout much of Europe since the 1960s. Consequently, many studies have focused on analysing habitat selection of European hares in order to improve the suitability of the habitat for this species. Habitat preferences of European hares are known to be affected by hare density, but most studies have been conducted in agricultural areas where hare densities were medium to high. Finding habitat preferences at high densities is difficult as most available habitats are occupied. In addition, in agricultural areas, field size might influence the hares’ habitat selection because it affects the distribution and availability of certain habitat types. However, most studies relate to areas with large field sizes. In this study, we analysed the habitat preferences of European hares in spring and autumn during the activity period, in the early hours of the night, in an agricultural area with low hare density and small average field size using Chesson’s electivity index. Moreover, we focused on the question whether two different habitat classifications varying in their specificity might cause contradictory results regarding European hares’ habitat preferences. Our results show that in this agricultural area with low hare density, European hares avoided several habitat types which were preferred in other study areas with higher hare densities. Therefore, we assume that hare density has an influence on the species’ habitat selection. In contrast, the small average field size of our study area seemed not to have an effect on hare habitat preference. Furthermore, by pooling habitat types into broader groups, substantial information was lost in some categories. Hence, for some categories, e.g. grassland or agricultural crop land, more detail might be needed than for others, such as urban areas, when analysing hares’ habitat selection. In conclusion, our results imply that studies on habitat preferences have to be conducted in areas with low hare density to be able to gain knowledge on the species’ habitat requirement and hereinafter improve the suitability of the habitat for this species. 相似文献
3.
Diet selection by hares (Lepus europaeus) in arable land and its implications for habitat management 总被引:1,自引:1,他引:0
Thomas Reichlin Erich Klansek Klaus Hackländer 《European Journal of Wildlife Research》2006,52(2):109-118
Populations of European hares (Lepus europaeus) have experienced a dramatic decline throughout Europe in recent decades. European hares are assumed to prefer weeds over
arable crops, and weed abundance was reduced by the intensification of agriculture. Therefore, modern agriculture has been
blamed as a major factor affecting European hare populations. However, it is questionable whether European hares select weeds
at all, as previous studies had major methodological limitations. By comparing availability and use of plants with Chesson’s
Electivity Index, we investigated whether the European hare actually feeds selectively on different plants in arable land.
Food availability and use were dominated by cultivated crops (e.g. winter wheat, spring barley and sugar beet). Diet selection
analysis revealed that in autumn and winter, European hares predominantly preferred cultivated crops (winter wheat) and food
items provided by hunters (tubers of sugar beet and carrot). In spring and summer, apart from soy, only weeds (e.g. clover
and corn poppy) were positively selected, especially after cereal crops were harvested. We suggest that the decline in European
hare populations throughout Europe was facilitated by the decrease in weed abundance. Wildlife-friendly set-asides in arable
land have the potential to reconcile the European Union’s Common Agricultural Policy with wildlife conservation. 相似文献
4.
Efficient, practical and accurate estimates of population parameters are a necessary basis for effective conservation action to meet biodiversity targets. The brown hare is representative of many European farmland species: historically widespread and abundant but having undergone rapid declines as a result of agricultural intensification. As a priority species in the UK Biodiversity Action Plan, it has national targets for population increase that are part of wider national environmental indicators. Previous research has indicated that brown hare declines have been greatest in pastural landscapes and that gains might be made by focussing conservation effort there. We therefore used hares in pastural landscapes to examine how basic changes in survey methodology can affect the precision of population density estimates and related these to national targets for biodiversity conservation in the UK. Line transects for hares carried out at night resulted in higher numbers of detections, had better-fitting detection functions and provided more robust density estimates with lower effort than those during the day, due primarily to the increased probability of detection of hares at night and the nature of hare responses to the observer. Hare spring densities varied widely within a single region, with a pooled mean of 20.6 hares km(-2), significantly higher than the reported national average of hares in pastures of 3.3 hares km(-2). The high number of encounters allowed us to resolve hare densities at site, season and year scales. We demonstrate how survey conduct can impact on data quantity and quality with implications for setting and monitoring biodiversity targets. Our case study of the brown hare provides evidence that for wildlife species with low detectability, large scale volunteer-based monitoring programmes, either species specific or generalist, might be more successfully and efficiently carried out by a small number of trained personnel able to employ methods that maximise detectability. 相似文献
5.
Conflicts between field sports, animal welfare and species conservation are frequently contentious. In Ireland, the Irish
Coursing Club (ICC) competitively tests the speed and agility of two greyhounds by using a live hare as a lure. Each coursing
club is associated with a number of discrete localities, known as preserves, which are managed favourably for hares including
predator control, prohibition of other forms of hunting such as shooting and poaching and the maintenance and enhancement
of suitable hare habitat. We indirectly tested the efficacy of such management by comparing hare abundance within preserves
to that in the wider countryside. In real terms, mean hare density was 18 times higher, and after controlling for variance
in habitat remained 3 times higher, within ICC preserves than the wider countryside. Whilst we cannot rule out the role of
habitat, our results suggest that hare numbers are maintained at high levels in ICC preserves either because clubs select
areas of high hare density and subsequently have a negligible effect on numbers or that active population management positively
increases hare abundance. The Irish hare Lepus timidus hibernicus Bell, 1837 is one of the highest priority species for conservation action in Ireland and without concessions for its role
in conservation, any change in the legal status of hare coursing under animal welfare grounds, may necessitate an increase
in Government subsidies for conservation on private land together with a strengthened capacity for legislation enforcement. 相似文献
6.
J. Langbein ‡ M. R. Hutchings § S. Harris C. Stoate † S. C. Tapper† S. Wray 《Mammal Review》1999,29(2):93-116
Over the last few decades, there have been significant declines in Brown Hare Lepus europaeus numbers throughout Europe, leading to concern for their status in many countries. In Britain, there were no quantified data on the extent of this decline, on current population levels, or any baseline against which to monitor future population changes. The need for a quantified national hare survey led to this evaluation of the techniques available to assess hare numbers. Published information on counting hares is reviewed, and various techniques compared by applying them to a number of sites in southern England. Three basic approaches are available: counts of inactive hares, counts of active hares and indirect methods. Counts of inactive hares include total clearance, wide belt and line transect counts. Total clearance counts give an absolute figure, but are labour intensive and can only be applied to restricted areas. Wide-belt assessments are difficult to apply in certain habitats and even in open areas tend to produce a substantial over-estimate. Line transect counts are easy to undertake and are not labour intensive but should only be applied to large areas, or data from several small areas combined. Counts based on active hares are more problematical, because it is difficult to determine what proportion of the population is inactive at any one time. Spotlight counts based on variable circular plots are the most accurate but difficult to apply widely, and twilight counts are very subjective in their interpretation, especially when surveying small areas or areas with a large proportion of concealing habitats. Of the indirect methods, dung pellet counts can be valuable in specific areas but are difficult to apply across a range of habitats. We concluded that, of the various techniques considered, line transect counts have the greatest potential for a national survey, but need to be stratified so that enough transects are undertaken within each habitat stratum to obtain a reliable mean population estimate for each stratum. 相似文献
7.
The Northern Ireland Hare Survey documented the distribution of the Irish Hare (Lepus timidus hibernicus). Historical game bag records and other, more contemporary, records of hare distribution were examined. These data indicate how numbers of L. t. hibernicus may have changed over the last 140 years. The results of the Northern Ireland Hare Survey suggested that L. t. hibernicus was widespread throughout Northern Ireland. Current average densities are no more than 0.65 hares/km2. Game bag records indicate that hare densities may have been much higher in the past, with a maximum of 138 hares/km2 recorded on Crom Estate, Co. Fermanagh, in 1864. Evidence from hare distribution recorded during the Northern Ireland Rabbit Survey indicates that hare numbers declined between 1984 and 1994. Evidence from all sources suggests that L. t. hibernicus has declined in abundance substantially, with present total population estimates for Northern Ireland ranging from 8250 to 21 000 individuals. Flushing data indicate that rushes and hedgerows are important diurnal resting areas for hares. While the principal reason for the decline in numbers of L. t. hibernicus in Northern Ireland is not clear, more species‐rich pasture and provision of areas of cover, such as rushes, may arrest further declines, or indeed promote numbers of hares, particularly in lowland areas. 相似文献
8.
The role of natural habitats in agricultural systems for bird conservation: the case of the threatened Lesser Grey Shrike 总被引:1,自引:0,他引:1
David Giralt Lluis Brotons Francisco Valera Anton Krištín 《Biodiversity and Conservation》2008,17(8):1997-2012
Birds of agricultural systems are one of the most threatened groups of birds in Europe mainly due to their sharp population
decline in recent decades. Habitat intensification resulting from more productive agricultural practices has been proposed
as a major cause for these declines. However, especially in some regions such as Eastern European and Mediterranean countries,
little is known about the ultimate factors linked to habitat intensification that drive population declines for different
species. The Lesser Grey Shrike is a good study species for a better understanding of such processes since it is closely related
to agricultural habitats in Europe and has suffered a strong decline in range and population size across the western half
of the continent. In this study, we explored variations in breeding parameters of this shrike related to habitat composition
and food supply at the territory level. We found that fledgling success of early breeders was related to the presence of natural
(shrub lands) and semi-natural (fallows) habitats in the predominantly agricultural matrix that dominated breeding territories.
Their influence on fledgling success appeared to be mediated by a higher arthropod availability on these habitats. Indeed,
Lesser Grey Shrike showed a strong preference for these habitats as hunting locations. Our results highlight the importance
of natural habitats in intensified agricultural land mosaics for the conservation of bird species. We suggest that management
plans should pay special attention to the availability of habitats which serve as high quality food reservoirs and can potentially
contribute to enhance the species population viability in an area. Finally, we discuss the possible link between agricultural
intensification and Lesser Grey Shrike population declines in Western Europe. 相似文献
9.
Selection of resting sites by the European hare as related to habitat characteristics during agricultural changes 总被引:1,自引:1,他引:0
The decline of the European hare Lepus europaeus populations has been shown to be correlated with agricultural intensification, which has caused loss of habitat heterogeneity.
We aimed to investigate the diurnal spring habitat selection using Jacobs’ second selection index in an intensively cultivated
farmland to reveal how the habitat choice by resting hares was affected by changes in the habitat availability. Clearance
counts of hares driven out of known areas were made during an 11-year field investigation within two sectors of a private
hunting ground located in the Paris basin (France). The loss of habitat heterogeneity included the disappearance of pastures
dedicated to a last remaining sheep farm in the area, the removal of non-cropped areas and field boundaries and the increase
of mean field size. Breeding stocks of hare declined during the study. Harrowed fields were always avoided. Pastures, alfalfa
fields, thickets and fallow land were selected at the start of our study, whereas the remaining part was avoided at the end.
The preference for ploughed fields decreased with the growth of vegetation in the winter-wheat fields. To benefit hares, land
management should provide year-round vegetative cover and food from non-cropped areas in intensive arable farms. 相似文献
10.
Martijn J. A. Weterings Sophie P. Ewert Jeffrey N. Peereboom Henry J. Kuipers Dries P. J. Kuijper Herbert H. T. Prins Patrick A. Jansen Frank van Langevelde Sipke E. van Wieren 《Ecology and evolution》2019,9(6):3457-3469
Spatial variation in habitat riskiness has a major influence on the predator–prey space race. However, the outcome of this race can be modulated if prey shares enemies with fellow prey (i.e., another prey species). Sharing of natural enemies may result in apparent competition, and its implications for prey space use remain poorly studied. Our objective was to test how prey species spend time among habitats that differ in riskiness, and how shared predation modulates the space use by prey species. We studied a one‐predator, two‐prey system in a coastal dune landscape in the Netherlands with the European hare (Lepus europaeus) and European rabbit (Oryctolagus cuniculus) as sympatric prey species and red fox (Vulpes vulpes) as their main predator. The fine‐scale space use by each species was quantified using camera traps. We quantified residence time as an index of space use. Hares and rabbits spent time differently among habitats that differ in riskiness. Space use by predators and habitat riskiness affected space use by hares more strongly than space use by rabbits. Residence time of hare was shorter in habitats in which the predator was efficient in searching or capturing prey species. However, hares spent more time in edge habitat when foxes were present, even though foxes are considered ambush predators. Shared predation affected the predator–prey space race for hares positively, and more strongly than the predator–prey space race for rabbits, which were not affected. Shared predation reversed the predator–prey space race between foxes and hares, whereas shared predation possibly also released a negative association and promoted a positive association between our two sympatric prey species. Habitat riskiness, species presence, and prey species’ escape mode and foraging mode (i.e., central‐place vs. noncentral‐place forager) affected the prey space race under shared predation. 相似文献