Hare Abundance Research Articles

Dune Hares: Population Indices, Home Range Size, and Habitat Selection of the European Hare on a Danish Island.

Population indices, such as transect counts of animals, can provide important information concerning population changes over time. Moreover, data concerning the home range size and habitat selection of individuals can provide valuable insight into spatial requirements of animals and how they can adapt to variable environments. Here, we describe the population development of European hares (Lepus europaeus) and investigated home range sizes and habitat selection of six radio-tagged individuals on the small (80 ha) Danish Wadden Sea island Langli. The average minimum hare population density from 1983 to 1997 was 64 ± 36 (mean ± SD) hares/km2, with hare numbers varying among years and seasons. The average home range size was 23.3 (CI: 18.9-28.7) ha, which is comparable to agricultural areas of high structural diversity. Moreover, hare habitat selection was generally bimodal, with hares moving over larger areas and selecting marsh habitat for foraging during nighttime, and dune and grassland habitat for resting during daytime, especially during winter. Combined, our results indicate that hare abundance and space use in the dunal landscape of Langli Island were similar to agricultural areas of comparatively high habitat quality. Thus, dunal marsh landscapes offer high-quality habitat for hares and might be of importance as population strongholds at a time when hare populations are declining in many agricultural areas across Europe.

Evidence for a survival-driven traveling wave in a keystone boreal predator population

Cyclical population dynamics are a common phenomenon in populations worldwide, yet the spatial organization of these cycles remains poorly understood. In this study, we investigated the spatial form and timing of a population collapse from 2018 to 2022 in Canada lynx (Lynx canadensis) across the northwest boreal forest. We analyzed survival, reproduction, and dispersal data from 143 individual global positioning system (GPS) collared lynx from populations across five study sites spanning interior Alaska to determine whether lynx displayed characteristics of a population wave following a concurrent wave in snowshoe hare (Lepus americanus) abundance. Reproductive rates declined across the study sites; however, site-level reproduction declined first in our easternmost study sites, supporting the idea of a population wave. Despite a clear increase in percent of dispersing lynx, there was no evidence of directional bias in dispersal following a hare population wave. Analysis did show increasingly poor survival for lynx dispersing to the east compared to combined resident and westward dispersal. This pattern is consistent with a survival-mediated population wave in lynx as the driver of the theorized population wave. The combination of these factors supports the idea of a hierarchical response to snowshoe hare population declines with a drop in lynx reproduction followed by increased dispersal, and finally reduced survival. All of this evidence is consistent with the expected characteristics of a population undergoing a traveling wave and supports the hypothesis that lynx presence may facilitate and mirror the underlying wave patterns in snowshoe hare.

Determining abundance predictors of the European Hare (Lepus europaeus), a global invader in southeastern Brazil

Abstract European Hare (Lepus europaeus), like many invasive species, have declined in much of their native range but flourished in non-native regions (e.g. South America). Previous studies suggested that loss of farmland heterogeneity due to agricultural intensification is the main driver of the species decline in its native range in Europe. Yet, little is known about the role of spatial and temporal heterogeneity and land cover types as predictors of European Hare local abundance in Neotropical agricultural landscapes. We hypothesized that spatial and temporal heterogeneity, rather than land cover types, would be the most influential predictors of hare local abundance in intensively managed Neotropical agricultural landscapes. We sampled 55 sites embedded within agricultural-dominated landscapes from southeastern Brazil with camera traps and transect surveys. Sites were selected along an uncorrelated gradient of native vegetation cover and compositional heterogeneity. We estimated the relative abundance of European hares using an occupancy model that accounts for imperfect detection of species induced primarily by variation in local abundance. We found that land cover diversity, sugarcane, and savanna cover were the best predictors of European Hare relative abundance. Hare relative abundance estimates were low and did not vary dramatically among sites, suggesting that this invader has not yet attained high local density in our study region. European Hare attained the highest relative abundance in agricultural landscapes that locally combine higher compositional heterogeneity, including sugarcane crops, and little to no native savanna. Areas with these combined features may represent the most important nascent foci, fostering ongoing northward spread of this invasive species in the Neotropics.

Population Density of European Hare Predicts Risk of Tularemia Infection, Czech Republic, 2006-2022.

Background: Over 200 different animal species are susceptible to infection by tularemia, highly infectious disease caused by Francisella tularensis. Hares (Lepus sp.) and small rodents, such as common vole (Microtus arvalis), have been acknowledged as the most significant sources of human tularemia infection in most European countries. Our objective was to verify ability of these species in predicting incidence of human tularemia in a Central European country, the Czech Republic. Materials and Methods: We used 17 years of data on densities of European hare (Lepus europaeus) and common vole, and climate variability to test effects of these factors on temporal dynamics of tularemia incidence. The data were obtained from annual reports available from online e-repositories. Results: The analysis showed that 33% of the yearly variation in human tularemia incidence was explained solely by the abundance of European hare in the Czech Republic during 2007-2022. Density of common vole and North Atlantic Oscillation index, a measure of climate variability, did not significantly explain tularemia incidence. While hare population declined severely during 1993-2022, we did not detect any clear accompanied decrease in the prevalence of tularemia in humans and hares. Conclusion: Contrary to expectations, only hares proved capable in predicting yearly dynamics in human tularemia incidence in the Czech Republic. We call for continued monitoring of infection rates in hares and advocate the use of hunter estimates of hare abundance as a cheap and effective means of predicting the risk of tularemia.

Differential impacts of spruce beetle outbreaks on snowshoe hares and red squirrels in the southern Rocky Mountains

Spruce beetles (Dendroctonus rufipennis) have impacted millions of acres of Engelmann spruce (Picea engelmannii) – subalpine fir (Abies lasiocarpa) forest in North America over the past decade, resulting in the most extensive outbreak in recorded history. This dramatic alteration of forest composition and structure has precipitated numerous changes to forest ecology and ecosystem services. Among the least studied of these changes are impacts to wild mammals, including snowshoe hares (Lepus americanus) and red squirrels (Tamiasciurus hudsonicus). We sampled a chronosequence of spruce-fir stands along a gradient of ‘years elapsed since spruce beetle outbreak’ (YSO) in order to estimate impacts to abundance of these two species in the southern Rocky Mountains. Snowshoe hare abundance was not related to YSO, at least in the first decade post-outbreak. Instead, hare abundance during this period was positively related to horizontal cover, especially that due to stem density of small diameter subalpine fir. Notably, snowshoe hare abundance was negatively related to stem density of small diameter Engelmann spruce, suggesting that elements of horizontal cover may not be uniformly beneficial to hares. Hare abundance was also negatively related to ground cover, which could help explain the lack of relationship to YSO, assuming reduction in overstory canopy would lead to increases in ground cover. Red squirrel abundance was negatively related to YSO and outbreak severity (i.e., basal area of large diameter dead trees). This was likely due to diminished cone crops in impacted areas, which red squirrels cache and rely on heavily to sustain them through the winter. Basal area of remaining large live fir trees was not related to squirrel abundance, suggesting that regeneration of spruce and associated cone crops may be necessary for recovery of red squirrels, which may take several decades.

Effects of compound disturbance on Canada lynx and snowshoe hare: Wildfire and forest management influence timing and intensity of use

Wildfires are increasing in scale and impact on the landscape, altering large amounts of wildlife habitat and forest ecosystems. The reduction of fuels through forest management is considered a primary way to reduce the extent and severity of wildfires before they occur but may lead to a decrease in tree density prohibitive of some species’ habitat. Alternatively, management actions undertaken after a fire may speed the trajectory of burned areas back into quality habitat but may also impede this development if the wrong type of treatment is undertaken. Thus, information on how different management actions, applied either pre- or post-fire, can influence the timing of a burned area’s return to suitable habitat will help managers conserve species on the landscape. Our study aims to understand how a rare carnivore, Canada lynx (Lynx canadensis), uses stands managed with different silviculture actions at different times relative to wildfire. We used GPS locations from 39 individual lynx collected from 2004 to 2015 to examine the response of lynx to wildfire compounded by active forest management, where time since fire at time of use ranged from 1 to 27 years. To understand the drivers behind lynx use of wildfires, we also focused on the primary prey of Canada lynx, snowshoe hares (Lepus americanus), using pellet counts across a similar range of post-fire treatment types in fires between 22 and 28 years old. We also assessed vegetation recovery and forest structure over time since wildfire using remotely sensed data and field measurements. We found that lynx intensity of use differed based on timing and type of management action, with the greatest lynx use ∼25 years after a wildfire managed with post-fire regeneration cuts (removal of the majority of the canopy). Lynx use was likely driven by hare abundance, which was also highest in post-fire regeneration cuts, characterized at time of use by dense lodgepole pine stands. We conclude that managing landscapes with a mosaic of active (pre- and post-fire treatments) and passive (hands-off) management will best conserve a desirable range of lynx habitat in an increasingly fire-impacted landscape.

Питание беркута на средней Лене, Якутия, Россия

Presented data on the Golden Eagle (Aquila chrysaetos) diet is based on the analysis of 291 pellets and 233 food remains found in or under nests and perches. Data was also obtained based on visual information. Small rodents were identified by teeth structure, birds – by femur and humerus sizes. If possible, species was determined by mammal hairs and bird feathers found in pellets or food remains. Information on the Golden Eagle diet was obtained between 2006 and 2023 in three administrative areas of Yakutia (Khangalassky and Namsky districts, administrative area of the city of Yakutsk) located in the basin of the middle reaches of Lena (Middle Lena). The study area has a wide and complexly terraced valley, 70% of which is covered by taiga with combination of coniferous (larch, spruce, pine) and small-leaved (willow, birch) forests, meadows, and agricultural land. The Middle Lena is characterized by an extremely continental climate and a short summer: average temperature in January is -43.2°, in June – +18,0°, frostfree period lasts 95 days. Previously Golden Eagle nested throughout the taiga of Yakutia, and until the early 1960s was a common species in the Middle Lena (Vorobiev, 1963). Since the 1970s–1980s a sharp decrease in its abundance was recorded, and since the 1990s it has become extremely rare (Solomonov, Larionov, 1976; Borisov, 1987; Isaev et al., 2020). According to our observations, since the beginning of the 2000s there was a gradual increase in the number of Golden Eagle and the emergence of breeding territories in areas where Golden Eagles were absent for a long-time during breeding period. Today, 33 Golden Eagle nests are known in the Middle Lena, breeding occurred in 11 of them. The Golden Eagle arrival is usually observed from the second decade of March to the first decade of April. Golden Eagle lays eggs in April, nestlings hatch in May and depart from nests in September–October. Research by Yu.V. Labutin (1992) shows that in the 1970s–1980s, the main food source for Golden Eagle in Central Yakutia was Mountain Hare (89%); according to G.P. Larionov et al., 1991, in the 1980s–1990s this species accounted for 37.7% of prey. It should be noted that in the beginning-middle of the 20th century, Mountain Hare was one of the most common species in Central Yakutia, and in years of its peak abundance – massive commercial species, as almost 850,000 hare skins were harvested then. A steady downward trend in the number of species has begun from the 1970s, the population size has decreased, mainly due to the anthropogenic factor (Solomonov, 1975). Since 2000s, hare hunting has ceased due to its low numbers in the region. Accounting that has been carried out in Central Yakutia in 2008–2018 showed that the number of species is very low – 0.2–0.3 individuals/10 km of the route (Sedalishchev, Odnokurtsev, 2022). As shown by the recent data, 11 mammal and 29 bird species are found in the Golden Eagle diet in Central Yakutia, and Long-Tailed Ground Squirrel has become its main prey. The predominance of Ground Squirrels in the diet suggests that, due to an increase in hare abundance, Golden Eagle switched to species with higher population density. The diet of Golden Eagle changes depending on the season. The greatest prey variety is observed in spring; eagles feed on young Roe Deer, Ground Squirrels, less often – hare, sable, etc. There are also reports of Golden Eagles attacking exhausted adult Roe Deer in early spring. It is worth noting that, judging by the survey data, Golden Eagles were often observed near fallen horses. While horse hairs were found in only one of the examined pellets, it confirmed Golden Eagle feeding on horse meat. From the beginning of June, Golden Eagle switch to its main prey, the Long-Tailed Ground Squirrel, occasionally feeding on small mammals and passerine birds. Interestingly, insects are sometimes found in pellets collected in Golden Eagle nests.

Estimating abundance, temporary emigration, and the pattern of density dependence in a cyclic snowshoe hare (Lepus americanus) population in Yukon, Canada

Estimates of demographic parameters based on capture–mark–recapture (CMR) methods may be biased when some individuals in the population are temporarily unavailable for capture (temporary emigration). We estimated snowshoe hare abundance, apparent survival, and probability of temporary emigration in a population of snowshoe hares (Lepus americanus Erxleben, 1777) in the Yukon (Canada) using Pollock’s robust design CMR model, and population density using spatially explicit CMR models. Survival rates strongly varied among cyclic phases, seasons, and across five population cycles. We found strong evidence that temporary emigration was Markovian (i.e., nonrandom), suggesting that it varied among individuals that were temporary emigrant in the previous sampling period and those that were present in the sampled area. The probability of temporary emigration for individuals that were in the study area during the previous sampling occasion (γ″) varied among cycles. Probability that individuals that were temporarily absent from the sampled area would remain temporary emigrants (γ′) showed strongly seasonal pattern, low in winter and high during summers. Snowshoe hare population density ranged from 0.017 (0.015–0.05) hares/ha to 4.43 (3.90–5.00) hares/ha and showed large-scale cyclical fluctuations. Autocorrelation functions and autoregressive analyses revealed that our study population exhibited statistically significant cyclic fluctuations, with a periodicity of 9–10 years.

The impact of variable predation risk on stress in snowshoe hares over the cycle in North America’s boreal forest: adjusting to change

The boreal forest is one of the world's ecosystems most affected by global climate warming. The snowshoe hare, its predators, and their population dynamics dominate the mammalian component of the North American boreal forest. Our past research has shown the 9-11-year hare cycle to be predator driven, both directly as virtually all hares that die are killed by their predators, and indirectly through sublethal risk effects on hare stress physiology, behavior, and reproduction. We replicated this research over the entire cycle by measuring changes in predation risk expected to drive changes in chronic stress. We examined changes in hare condition and stress axis function using a hormonal challenge protocol in the late winter of 7years-spanning all phases of the cycle from the increase through to the low (2014-2020). We simultaneously monitored changes in hare abundance as well as those of their primary predators, lynx and coyotes. Despite observing the expected changes in hare-predator numbers over the cycle, we did not see the predicted changes in chronic stress metrics in the peak and decline phases. Thus, the comprehensive physiological signature indicative of chronic predator-induced stress seen from our previous work was not present in this current cycle. We postulate that hares may now be increasingly showing behavior-mediated rather than stress-mediated responses to their predators. We present evidence that increases in primary productivity have affected boreal community structure and function. We speculate that climate change has caused this major shift in the indirect effects of predation on hares.

Agri-environment schemes do not support Brown Hare populations due to inadequate scheme application

The goal of many agri-environment schemes (AES) is to increase biodiversity in agroecosystems. AES effects are often measured on invertebrates and birds; mammals as indicator species are infrequently targets of such researches. Our goal was to evaluate the local-scale effects of the Hungarian Agri-Environmental Measures (AEM) on the European brown hare (Lepus europaeus), which shows decreasing population trends across Europe. We compared hare abundances and their dropping numbers in AEM and control agricultural arable and grassland fields of 17 game management units in two seasons. We also examined the quality of arable fields based on their margin width and vegetation cover. We found that margin quality was higher in AEM than in the control fields. Control grasslands had higher vegetation quality than the AEM grasslands. We found a significant difference in hare counts between AEM and control arable fields in spring but no difference in autumn. The dropping densities did not differ in any season, treatment category or agroecosystem type. We conclude that the AEM program (2009-2014) in Hungary was not effective for the hare, and this might have been caused by the inadequate or weak application of AEM practices. We provide recommendations for future AEM programs to enhance biodiversity.

Effects of factors associated with the decline of brown hare abundance in the Vojvodina region (Serbia)

Effects of factors associated with the decline of brown hare abundance in the Vojvodina region (Serbia)

Fine-scale habitat selection by sympatric Canada lynx and bobcat.

The Canada lynx (Lynx canadensis) and the bobcat (Lynx rufus) are closely related species with overlap at their range peripheries, but the factors that limit each species and the interactions between them are not well understood. Habitat selection is a hierarchical process, in which selection at higher orders (geographic range, home range) may constrain selection at lower orders (within the home range). Habitat selection at a very fine scale within the home range has been less studied for both lynx and bobcat compared to selection at broader spatiotemporal scales. To compare this fourth‐order habitat selection by the two species in an area of sympatry, we tracked lynx and bobcat during the winters of 2017 and 2018 on the north shore of Lake Huron, Ontario. We found that both lynx and bobcat selected shallower snow, higher snowshoe hare abundance, and higher amounts of coniferous forest at the fourth order. However, the two species were spatially segregated at the second order, and lynx were found in areas with deeper snow, more snowshoe hare, and more coniferous forest. Taken together, our findings demonstrate that the lynx and bobcat select different resources at the second order, assorting along an environmental gradient in the study area, and that competition is unlikely to be occurring between the two species at finer scales.

Positive effects of set-asides on European hare (Lepus europaeus) populations: Leverets benefit from an enhanced survival rate

Since agricultural intensification started in the early 1900s, farmland biodiversity in Europe has decreased. Non-farmed features are of high importance for the promotion of plant and animal species including the European hare (Lepus europaeus). As an immediate cause of the decline in European hare abundances, a reduction in reproductive success has been proposed. Female fertility is not impaired and leveret mortality is inherently high in this lagomorph species. However, hunting bags suggest that leveret mortality has increased in recent decades. We studied the effect of set-asides on population trends of hunted European hares by analysing data of spotlight counts and of hunting bags in arable landscapes in Lower Austria during six years. We found no interannual and interareal differences in reproductive output of adult females. Accordingly, female reproductive output had no effect on population growth of the hares. Leveret survival rate was higher in the study sites with a high proportion of set-asides (9 and 13%) than in the sites with a lower proportion of set-asides (3 and 5%). We recorded a positive effect of leveret survival rate on population growth and next year's spring density. Moreover, the proportion of set-asides positively affected spring density, population growth, hunting bag, leveret survival rate and number of subadults in autumn. Hence, set-asides contribute to the survival of leverets and, correspondingly, population growth and spring density. Accordingly, set-asides are a highly important habitat measure and an evidence-based conservation tool for the promotion of this species in arable landscapes.

The role of maize cultivation on European hare abundance

Agricultural areas make up over one third of the worlds’ terrestrial area, with past and ongoing agricultural land use change and intensification being a major threat to many animal populations. In Europe, maize grown for biofuel and fodder is increasingly replacing traditional crop types, which might affect wildlife populations. Here, we used spotlight counts to estimate densities of the European hare (Lepus europaeus), a declining farmland species, on a landscape scale in Denmark. Our main objective was to investigate if hare density was affected by the proportion of maize and other vegetation types, while controlling for other factors including habitat heterogeneity and predator abundance. We found that hare density decreased with increasing maize cover, whereas no other vegetation type affected hare density. This suggests that continued expansion in maize cultivation will likely lead to further population declines of hares, potentially because greater maize cover replaces crops and areas that are more valuable for wildlife. Thus, incentivizing maize as energy source for biogas production will likely have adverse effects on animal populations such as hares and other farmland species, ultimately leading to decreased biodiversity.

Potential functional and numerical response in a large sized raptor may be mediated by the abundance of an exotic lagomorph

Predators relying on a particular prey as their main food resource are especially susceptible to fluctuation in prey availability. When prey abundance decreases they show a functional response by adjusting their diet. After this, predators may suffer a numerical response. These responses have been poorly studied in presence of alien invasive preys. The black-chested buzzard-eagle (Geranoaetus melanoleucus) is a large raptor inhabiting open areas of South America. Here we present the first long-term study on this eagle population tendency, analyzing functional and numerical responses associated with changes in the abundance of the exotic European hare (Lepus europaeus). We measured breeding performance and studied eagles’ diet during the breeding seasons of 1991, 1992, 2006, 2011 and 2012. We also estimated the relative abundance of hares in those years. Eagles diets changed over the years with a decrease in hare consumption. The number of eagles decreased from 1992 to less than half in 2012. Forty one percent of the total eagles observed in 1991/92, and 27% in 2006 were immature, while in 2011 and 2012 no immature were observed. We found similar tendencies of decrease in the abundance of hares which suggest that the decrease in eagles population may be related with the decreasing tendency of hares. No other factor that may have affected immature eagles abundance was evident in the area during this period. Our data suggest that changes in the abundance of an exotic lagomorph may lead numerical and functional responses in a top predator by affecting its diet, age structure, and ultimately abundance.

Colonization and habitat selection of a declining farmland species in urban areas

Despite the accelerating global urbanization and its associated implications for wildlife and humans, we know little about the biology of urban ecosystems. Here, we investigated colonization and habitat selection of the European hare (Lepus europaeus), a declining farmland species, in urban areas in Denmark, using a combination of citizen science data and transect counts. Further, we estimated the population density of urban hares in Aarhus, Denmark’s second largest city. Our results provide the first evidence that hares have established populations in urban areas, potentially in response to decreasing habitat quality in rural areas due to agricultural intensification. The hare density in Aarhus was ca. 8 hares per km2, which is comparable to or slightly higher than hare abundance estimates from various pastural areas in Europe, suggesting that urban areas provide suitable habitat for hares. Hare habitat selection was generally associated with areas consisting of large lawns, such as high buildings and parks, which potentially provide high-quality forage throughout the year. Considering the increasing expansion of urban areas and deteriorating habitat quality of agricultural areas, urban planning that incorporates habitat requirements for wildlife could help to support urban animal populations, especially for species of conservation concern.

Mitigating bioenergy-driven biodiversity decline: A modelling approach with the European brown hare

The cultivation of energy crops leads to direct and indirect land use changes that impair the biodiversity of the agricultural landscape. In our study, we analyse the effects of mitigation measures on the European brown hare (Lepus europaeus), which is directly affected by ongoing land use change and has experienced widespread decline throughout Europe since the 1960s. Therefore, we developed a spatially explicit and individual-based ecological model to study the effects of different landscape configurations and compositions on hare population development. As an input, we used two 4 × 4 km large model landscapes, which were generated by a landscape generator based on real field sizes and crop proportions and differed in average field size and crop composition. The crops grown annually are evaluated in terms of forage suitability, breeding suitability and crop richness for the hare. In six mitigation scenarios, we investigated the effects of a 10 % increase in the following measures: (1) mixed silphie, (2) miscanthus, (3) grass-clover ley, (4) alfalfa, (5) set-aside, and (6) general crop richness. All mitigation measures had significant effects on hare population development. Compared to the base scenario, the relative change in hare abundance ranged from a factor of 0.56 in the grass-clover ley scenario to -0.16 in the miscanthus scenario. The mitigation measures of mixed silphie, grass-clover ley and increased crop richness led to distinct increases in hare abundance in both landscapes (> 0.3). The results show that both landscape configuration and composition have a significant effect on hare population development, which responds particularly strongly to compositional changes. The increase in crop diversity, e.g., through the cultivation of alternative energy crops such as mixed silphie and grass-clover ley, proves to be beneficial for the brown hare.

A 20-year experiment on the effects of deer and hare on eastern hemlock regeneration

Eastern hemlock (Tsuga canadensis (L.) Carrière) is a shade-tolerant, slow-growing tree once common in forests across the Great Lakes region. It was heavily exploited in the late 19th and early 20th centuries and now experiences limited regeneration across much of its range. This failure to regenerate has been ascribed to poor seedbed conditions, insufficient canopy openings, warmer climate, and browsing by white-tailed deer (Odocoileus virginianus (Zimmermann, 1780)) or snowshoe hare (Lepus americanus Erxleben, 1777). To test whether deer or hare limit hemlock regeneration, we studied >2000 hemlock seedlings inside and adjacent to experimental deer exclosures at 59 sites randomly distributed across hemlock and hemlock-component stands in northern Wisconsin and the western Upper Peninsula of Michigan in the United States. We monitored local deer and hare abundance, seedling growth, and seedling survival for 20 years. Two First Nations reservations showed lower deer density and greater survival and growth of unprotected seedlings than three national forests of the United States. Cohorts of hemlock seedlings protected from deer survived at a rate four times higher than those exposed to deer (59.3% vs. 15.0%) and shared a combined height 5.2 times greater. Hare densities significantly affected seedling survival only within exclosures. This extensive, long-term study identifies deer as the primary factor constraining hemlock regeneration in the region.

Impact of wildfire size on snowshoe hare relative abundance in southern British Columbia, Canada

BackgroundLarge wildfires result in more heterogeneous fire scars than do smaller fires because of differences in landscape context and high variability in burn intensity and severity. Previous research on mammal response to wildfire has often considered all fires as comparable disturbances regardless of size. Here, we explicitly examine whether fire size affects relative abundances of a keystone herbivore, snowshoe hare (Lepus americanus Erxleben, 1777), in regenerating stands of the same age. We surveyed vegetation and fecal pellets of snowshoe hares in nine 13-year-old wildfires, specifically, three fires in three size categories—small (80 to 200 ha), medium (1000 to 5000 ha), and large (>10 000 ha)—and in mature forests in southern British Columbia, Canada.ResultsSnowshoe hare density was low (0.4 hares ha−1), but hares were present at 57% of mature sites. Hares were absent from all areas where small fires had burned and were found in only one medium area post fire (0.2 hares ha−1). Hares were found within the fire scars of all three large burned areas, and with much higher numbers (3.8 hares ha−1) than in the medium fire area or mature forest. Snowshoe hare abundance was highly correlated with the number of sapling trees, especially lodgepole pine (Pinus contorta Douglas ex Loudon). Sapling densities were highly variable, but dense stands of saplings were found only in burn scars from large wildfires.ConclusionsFire size is an important predictor of snowshoe hare relative abundance in areas that are regenerating post fire; fires of different sizes are not comparable disturbances. Specifically, the post-fire heterogeneity after large fires enabled both the highest hare numbers as well as patches with no hares. These results suggest that forest and wildlife managers should protect areas with dense regeneration post fire, as these sites are necessary for hares after large wildfires.

Habitat requirements of the European brown hare (Lepus europaeus Pallas 1778) in an intensively used agriculture region (Lower Saxony, Germany)

BackgroundThe European brown hare (Lepus europaeus) typically resides in open habitats in agriculturally dominated landscapes in Europe. Over recent decades, a widely observed population decline occurred, which was attributed to agricultural intensification. However, with political incentives for specific crops, especially maize for energy production, the habitat went through massive changes. Thus, there is the need to identify parameters that characterize a suitable habitat for the brown hare in today’s agricultural lands.ResultsWe modelled European brown hare densities spatially and temporally explicit over 10 years (2005–2014) across an entire federal state. The generalized additive mixed model confirms a constant decline of the European brown hare population in Lower Saxony. Municipalities with a high proportion of grassland and precipitation totaling up to 900 mm are more favored. Woodland showed an approximately linear negative effect. The most important agricultural crop groups such as winter grains and winter oilseed rape showed overall positive effects on hare densities. However, the effect of maize was unimodal, with a positive effect of medium proportions, but a negative effect of very high proportions. The effect of sugar beet was relatively weak but negative. Brown hares were also more abundant in municipalities with a higher density of vixen with litter and municipalities with a high proportion of wildflower strips showed higher brown hare abundance.ConclusionLower Saxony is a diverse federal state with grassland dominated areas in the northwest, more woodland in the east, but intensive arable land in most remaining areas. The European brown hare—a species with a wide ecological potency—shows preferences to both grassland and the most typical arable crop groups such as winter grains and winter oilseed rape. The substantial increase in maize production within the time frame was likely unfavourable and may be one reason for the decline. Nonetheless, political tools such as the agri-environmental scheme “wildflower strips” were beneficial for the brown hare abundance and may be an option to reverse the decline seen over the 10 years.