Deer Fence Research Articles

Wildlife fencing at German highways and federal roads – requirements and management implications

In Germany, the high risk of wildlife–vehicle collisions (WVC) is further increasing due to increasing traffic volumes and road densities as well as the growing population densities of common ungulate species. As a result, threats to human health and property as well as wildlife mortality of widely spread and rare species increase. Currently, three basic types of wildlife fences are used in Germany: type A, a conventional galvanized‐high tensile deer fence (made of knot braid); type B, a chain wire (mesh wire) fence; type C, a rigid welded wire mesh fence panels. Since fencing needs to restrict access of many different species with different behaviours (e.g. jumping, climbing, digging), fencing needs to be multifaceted to be effectively. Furthermore, the occurrence of wildlife species with habits such as jumping, climbing or digging determines the optimal (functional) fence design per location. We surveyed road managers in combination with a personal assessment of road sections in Germany and derived the following recommendations for optimal fencing to reduce WVC: 1) To deter digging, use plates made of recycled synthetic materials or a concrete foundation, instead of barbed wire. 2) Fencing should be made of chain wire (mesh wire, type B) fence or rigid welded wire mesh fence panels (type C) instead of knot braid mesh (type A). 3) To restrict climbing, use angled chain wire fence or rigid welded wire mesh fence panels at the top of the fences. 4) Maintain fences so that they are kept free from ingrown vegetation/woods. Maintenance conditions should be considered while planning and building the fence, especially to ensure sufficient space on both sides for accessibility. 5) Fencing should be established preferably near the roadside and moved away from property lines. In conclusion, wildlife fencing could be a very effective mitigation measure to prevent WVC with common as well as protected species, when proper designed and recommendations of the survey will be consequently considered. Currently many wildlife fences lack functionality due to an inappropriate design and maintenance issues in Germany.

Clear‐cutting triggers regeneration of abandoned secondary forests but risks alternative successional trajectories with high deer density

AbstractQuestionsDoes clear‐cutting intended to boost regeneration of abandoned secondary forests lead to an irreversible shift to non‐forest vegetation under high deer density?LocationWarm‐temperate forests in Boso Peninsula, Chiba Prefecture, Japan.MethodsWe designed a factorial experiment including two levels of forest canopy treatment (clear‐cutting or intact canopy) and two levels of herbivory control (presence or absence of deer) using 24 plots of 10 m × 10 m. Vegetation dynamics occurring under each experimental treatment were tracked for 7.5 years.ResultsGround vegetation under the closed canopy did not change significantly for 7.5 years both inside and outside the deer fences. However, plots were rapidly covered by early‐seral plants till 1.5 years after the cutting event. The quick growth of ground vegetation after clear‐cutting was supported by plants that are known to have soil seed banks, as suggested by their ubiquity immediately after clear‐cutting. Species richness of ground vegetation was maximized at that time and gradually decreased afterward, suggesting biological filtering. This filtering process worked differently inside and outside the deer fences, resulting in different types of vegetation. The clear‐cut‐and‐fence plots became dominated by tree recruits that will recover secondary forests in the future. Contrastingly, vegetation outside the fences lacked many species (e.g., common tree species) that were found inside the fences and became dominated by shrubs and plants unpalatable to deer. This post‐cutting vegetation outside the fences was not similar to that inside the deer fences at any seral stage. This means that the vegetation outside the fences could be tracking an alternative successional trajectory rather than a case of arrested succession.ConclusionsHere, abandoned secondary forests still seem to maintain a high regeneration potential that would be triggered by clear‐cutting, but reducing herbivory pressure by deer is necessary to avoid the risk of alternative successional trajectories.

Conservation of endangered and rare plants requires strategies additional to deer‐proof fencing for conservation of sub‐alpine plant diversity

AbstractQuestionsDeer‐proof fencing is an essential conservation tool to protect and recover plant species diversity in deer‐overbrowsed ecosystems, including species‐rich sub‐alpine grasslands. However, community‐level conservation tools (such as fencing) may be insufficient for single‐species conservation, particularly for non‐target endangered or rare species that are sparsely distributed. We examined whether fencing that can protect and recover total plant species richness also benefits non‐target endangered or rare species.LocationA sub‐alpine semi‐natural Kirigamine grassland in Nagano Prefecture, Japan.MethodsWe conducted two complementary plant surveys (typical vegetation survey using 1‐m2 sampling units and flowering survey using 150‐m2 sampling units) to account for scarce species. We examined the community‐level responses (species richness, flowering species richness, and flowering abundance) of all species and endangered or rare species and the species‐level responses (occurrence and flowering abundance) of each species to deer fences.ResultsFencing benefited not only the community‐level response of all species, but also that of endangered or rare species. As species‐level responses, about half of 43 endangered or rare species had greater flowering abundance inside the fences than outside, but only three of them showed a positive effect on their occurrence. These results suggest that once an endangered or rare species has disappeared, it may be difficult to recover.ConclusionsContinued placement of deer fences is necessary to protect community‐level plant species richness of sub‐alpine endangered and rare species in deer‐overbrowsed ecosystems. We also highlight the necessity of additional strategies focusing on non‐target individual species across broad areas outside fences.

Verification of watershed-scale deer fence for conservation of ecosystem functions and its practicality for efficient maintenance in a cool-temperate natural forest in Ashiu, central Japan ―Ashiu Biological Conservation (ABC) Project―

Verification of watershed-scale deer fence for conservation of ecosystem functions and its practicality for efficient maintenance in a cool-temperate natural forest in Ashiu, central Japan ―Ashiu Biological Conservation (ABC) Project―

長野県霧ヶ峰高原での防鹿柵設置による絶滅危惧動植物の保全・再生効果 ―霧ヶ峰高原研究会―

長野県霧ヶ峰高原での防鹿柵設置による絶滅危惧動植物の保全・再生効果 ―霧ヶ峰高原研究会―

Does the local conservation practice of cultural ecosystem services maintain plant diversity in semi-natural grasslands in Kirigamine Plateau, Japan?

Wildflower viewing is recommended as a form of ecotourism in protected areas to facilitate conservation practices; but this relationship between the conservation of attractive flowering plant species and whole plant diversity has not been quantitatively evaluated. The Kirigamine Plateau in Japan encompasses a protected area that supports high grassland species diversity. Browsing activity by the expanding sika deer populations has negatively impacted this region in recent decades, drastically decreasing blooming flower resources that attract ecotourism. The effectiveness of conserving plant diversity through the placement of deer fences by local conservation practices was evaluated, and indicator species requiring future conservation strategies were identified. Compared to outside the deer fences, the five species diversity metrics (flowering plant richness, flowering abundance, flowering functional diversity (flowering FD), plant species richness, and threatened plant species richness) were significantly higher inside the fences. Except for flowering FD, plant species richness was positively correlated with all other species diversity metrics. The important species analysis identified four species as indicators of conservation for plant diversity and flowering FD out of the top 20 indicator species. The construction of deer fences had a strong positive effect on the preservation of four diversity metrics. However, to conserve flowering FD, additional strategies need to be implemented in this area. Conservation planning based on flowering plant diversity and cultural ecosystem services is vital in reducing the loss of biodiversity in semi-natural grasslands in protected areas worldwide.

Construction of deer fences restores the diversity of butterflies and bumblebees as well as flowering plants in semi-natural grassland

The abundance of both flower-visiting insects and flowering plants in semi-natural grasslands in temperate zones has declined as a result of overbrowsing by deer. The construction of deer fences is an effective method for biodiversity conservation because these fences prevent the invasion of deer. However, few studies have elucidated the biodiversity conservation effects of deer fences in semi-natural grasslands. Here we investigated the effects of the construction of deer fences on the diversity of butterflies, bumblebees, and flowering plants on the Kirigamine Plateau, Nagano Prefecture, Japan, which is covered by semi-natural grassland. The number of species of flowering plants inside the deer fences was higher than that outside the deer fences. The numbers of individuals and species of flower-visiting butterflies and bumblebees also tended to be higher inside the deer fences than outside the deer fences. On the other hand, there tended to be no difference in the number of individuals and species of non-flower-visiting butterflies inside and outside the deer fences. The diversity of flowering plants, butterflies, and bumblebees within the fenced areas was not substantially affected by the size of the fenced-off area. Our findings suggested that the construction of deer fences can contribute to the conservation of both flower-visiting insects and flowering plants in semi-natural grassland.

Summer precipitation limits plant species richness but not overall productivity in a temperate mesic old‐field meadow

AbstractQuestionWater availability is a primary regulator of plant productivity and species richness in arid and semi‐arid ecosystems, but its influence in other habitats is much less clear partly because experimental manipulations of water are relatively rare. How important is soil moisture availability relative to other key environmental factors in determining plant species biomass and diversity in temperate mesic grasslands?LocationAn old‐field meadow in southeastern Ontario, Canada.MethodsWe established a long‐term factorial field experiment to investigate how variation in soil water (achieved by rainout shelters and water additions), nutrients (NPK fertilizer additions), and above‐ground herbivory (deer fence exclosures), interact as regulators of plant production, species richness, and species composition. Above‐ground biomass for each species was determined in replicate plots (1 m2, n = 10) after five years of treatment applications.ResultsThe rainout shelters reduced community shoot biomass by 35% relative to ambient (control) plots, with no influence of the fertiliser. To our surprise, however, the fertiliser enhanced community biomass in the ambient and water addition plots to a similar extent. Species richness and Shannon diversity were increased by water addition, but reduced by the rainout shelters and by fertilisation. Total species richness across all replicate plots was 60% higher in the water addition treatment, and almost halved in the water‐reduced treatment. In contrast to the above, the exclosures had negligible impacts on these community variables.ConclusionsTogether, these results suggest that in old‐field meadow grasslands: (a) shoot productivity is primarily limited by soil nutrient supply except under drought conditions when water availability becomes the primary constraint; (b) the two main soil resources for plants — water and nutrients — affect productivity and species richness/composition in fundamentally different ways; and (c) future increases in summer soil aridity and anthropogenic nitrogen deposition may interact to reduce vegetation productivity and diversity in temperate mesic ecosystems.

Modelling multi‐species and multi‐mode contact networks: Implications for persistence of bovine tuberculosis at the wildlife–livestock interface

Abstract Individual‐ and species‐level heterogeneity in contact rates can alter the ability of a pathogen to invade a host community. Many pathogens have multiple modes of transmission—by direct or indirect contact. It is important to identify the role of heterogeneity in different types of transmission when managing the risk of disease spillover at the interface among different host species. We developed a network‐based analysis to explore how individual‐ and species‐level heterogeneity shape multi‐mode contact networks. We applied this network‐based approach to contact data from proximity loggers collected in a multi‐species host community that contributes to the spillover of the disease bovine tuberculosis (bTB) to cattle populations in Michigan, USA. We used this approach to (a) quantify how individual‐ and species‐level heterogeneity influence direct and indirect contacts in this system, (b) explore how management interventions to control spillovers, such as the installation of deer fences, can alter observed contact networks and c) predict the role that wildlife species have in maintaining bTB in the community. We found that individual‐ and species‐level heterogeneity disproportionately influenced indirect and direct contact networks, with individual‐level heterogeneity having a greater effect on indirect contact networks and species‐level heterogeneity having a greater effect on direct contact networks. We also found that the installation of deer fences significantly reduced deer‐specific indirect contacts. We used the results from our network analysis to show that white‐tailed deer (Odocoileus virginianus) could act as the sole reservoir host for bTB in this community with important implications for understanding past bTB dynamics and managing the persistence of bTB in the future. Synthesis and applications. Analyses of epidemiological networks rarely account for multiple modes of contact, which can lead to an incomplete understanding of how individual‐ and species‐level heterogeneity affect disease transmission. The multi‐mode, multi‐species network analysis we develop in this study illustrates that individual‐ and species‐level heterogeneity can play significantly different roles depending on the type of contact network considered. This has important implications when managing disease at the wildlife–livestock interface, where strategies may need to be multi‐pronged to account for the variable role of heterogeneity on different modes of contact.

Study on Effective Maintenance and Management Method of Deer Fence

Study on Effective Maintenance and Management Method of Deer Fence

To jump or not to jump: Mule deer and white‐tailed deer fence crossing decisions

ABSTRACTModified fencing structures have been recommended with the intention of enhancing ungulate movement. Ungulates such as mule deer (Odocoileus hemionus) and white‐tailed deer (O. virginianus) typically negotiate fences by jumping over them. We examined 2 fine‐scale fence crossing decisions to determine factors influencing 1) crossing success and 2) the mode of crossing by 2 sympatric deer species. From 2010 to 2016, we used remote cameras along fence lines in 2 study areas—Canadian Forces Base Suffield in southeastern Alberta, Canada, and The Nature Conservancy's Matador Ranch in north‐central Montana, USA—that captured images of deer–fence interactions before and after fence modifications were installed. We used logistic regression to model the probability of deer successfully crossing a fence and mode of crossing (jumping over vs. crawling under) based on fence characteristics and demographic factors. We documented 486 crossing attempts, of which 313 were successful (64.4%), indicating that pasture fences acted as a semipermeable barrier to deer. Of these 313 successful attempts, 152 crawled under the fence (48.6%) as opposed to jumping over it. We documented behavioral differences in mode of crossing between species when successfully crossing a fence. Results indicate that deer are selecting known crossing sites at broad scales as places to negotiate fences, and when assessing finer scale decisions at these sites, white‐tailed deer seemed to acclimate better than mule deer to our imposed changes (switched from crawling under to jumping over the fence). Though sample size was low in terms of use at modified fence sites, we recommend visually inconspicuous modifications (such as clips to increase the bottom wire height as opposed to goat‐bars) when implementing pasture fencing that was friendlier for deer. We also recommend modifications be implemented strategically; placement of modifications may be just as important to consider as the modification type. © 2018 The Wildlife Society.

Actual Conditions of the Deer Fence and Damage Control of Sika Deer in Clearcut -and- Reforestation Sites

Actual Conditions of the Deer Fence and Damage Control of Sika Deer in Clearcut -and- Reforestation Sites

Susceptible conditions for debarking by deer in subalpine coniferous forests in central Japan

Recently, deer have expanded their distribution to higher altitude ranges including subalpine forests. However, culling deer and construction of deer fence in subalpine forests are difficult because of steep slopes and complex topography. Thus it is necessary to clarify the factors which are associated with debarking by deer for the effective protection of subalpine forests. In this study, we examined which factors are associated with debarking by sika deer (Cervus nippon) in subalpine coniferous forests. We conducted our survey in Minami-Alps National Park, central Japan. We established 24 10 m × 40 m plots and surveyed the occurrence of debarking on saplings >30 cm in height and 3 cm in DBH, as well as sapling density within each plot. Minimum distances to nearest grassland of plots were calculated (tentatively assuming grassland would attract deer and would cause high debarking pressure in the surrounding subalpine forests). The mean percentage of debarked live saplings was higher than that of live trees. The mean percentage of debarked saplings which had already died was 81.6 %. Debarking of saplings increased with lower elevation, taller sapling size, and marginally increased near grassland. Sapling density was lower in plots with low basal area of conspecific trees near grassland and differed among species. Sapling density marginally decreased with decreasing elevation and increasing stand tree density. Debarking of trees was positively related to small DBH and low elevation, and marginally increased near grassland and differed among species. Our results suggest that tall saplings in subalpine forests of low elevation or near subalpine grassland were susceptible to debarking by deer and monitoring of these areas may permit the early detection of the impacts of deer in subalpine coniferous forests.

Quantifying deer and turkey leaf litter disturbances in the eastern deciduous forest: have nontrophic effects of consumers been overlooked?

Vertebrate herbivores and omnivores modify forest regeneration not only via direct and indirect trophic pathways, but also via nontrophic pathways such as litter and soil disturbances that may favor the regeneration of some species but not others. Deer are overabundant throughout vast portions of the eastern deciduous forest, and turkeys, once nearly extirpated, are now far more common; their foraging habits disturb litter over large areas, though this has rarely been evaluated. We quantified the size and frequency of litter disturbances created by both deer and turkeys. In addition, we tested the hypothesis that excluding vertebrates via fences would cause a reduction in the abundance and size of litter disturbances. We tested this hypothesis inside and outside six exclosures and adjacent control plots in an old-growth deciduous forest in Pennsylvania. Bare soil patches were ∼60% smaller and between 50% and 90% less abundant inside exclosures. The mean size of turkey litter disturbances was large (mean > 30 m2) and significantly greater than deer disturbances (p = 0.002), though turkey disturbances were less frequent. Our findings should apply broadly and are some of the first to demonstrate the extent of turkey disturbances. In addition, we demonstrate that exclosure studies reduce physical disturbances as well as browsing, both of which may synergistically act to cause changes in forest communities. We also caution that many deer fences exclude other vertebrates such as turkeys, which are important herbivores, seed predators, and major agents of disturbance. Consequently, we argue that studies that use fences to exclude deer should explicitly consider nontrophic indirect effects, particularly leaf disturbances and the potential impact of other large consumers as well (e.g., turkeys).

Red deer exclusion and saxicolous cryptogam community structure

AbstractDeer exclosure is an important management strategy for encouraging woodland regeneration in the presence of high numbers ofCervus elaphusL. This could pose a threat to important saxicolous lichen communities as a result of competition from bryophytes and other vegetation. This investigation compared the bryophyte and lichen communities associated with siliceous rock outcrops and boulders inside and outside a number of exclosures in wet heath vegetation at the Gruinard, Letterewe and Little Gruinard estates in Wester Ross. Species cover data were recorded from 6600·2×0·2 m quadrats, allocated to three different aspects of rocks, from 22 pairs of plots (placed either side of a deer fence) with randomization at each level of this hierarchy. The data were analyzed using linear mixed effects models. Mean lichen cover, diversity and species richness were significantly lower in quadrats on rocks within the exclosures. Mean bryophyte cover was significantly higher in quadrats on rocks inside the deer fence and was shown to have a highly significant negative relationship with total lichen cover. Saxicolous lichen species are particularly affected by the increase in shading and litter accumulation from the surrounding plants and the subsequent growth of bryophytes and heath vegetation on rocks within the exclosures. The results of this study have implications for the use of exclosures at locations where there are important saxicolous lichen communities.

間伐したヒノキ人工林における下層植生の回復に対する防鹿柵の効果 (II) -間伐から2年間の経過‐

間伐したヒノキ人工林における下層植生の回復に対する防鹿柵の効果 (II) -間伐から2年間の経過‐

Deer Fence, and: March Snow, and: I Married You, and: To Speak in Tongues

Deer Fence Inside the new deer fence wildflowers, absent for years, cover our hill again with half forgotten flecks of white, like so many ghosts of themselves on the dark floor of the forest. I pick a bunch: tooth wort, and dutchman's breeches, so luminous with mystery we must tame them with the names of household things. But where are the deer now? What other woman's flowers fill their mouths with the soft colors of spring? March Snow There is something hopeful about March, something benevolent about the light, and yet wherever I look snow has fallen or is about to fall, and the cold is so unexpected, so harsh, that even the spider lily blooming [End Page 17] on the windowsill seems no more than another promise, soon to be broken. It is like a lover who speaks the passionate language of fidelity, but when you look for him, there he is in the arms of winter. I Married You I married you for all the wrong reasons, charmed by your dangerous family history, by the innocent muscles, bulging like hidden weapons under your shirt, by your naive ties, the colors of painted scraps of sunset. I was charmed too by your assumptions about me: my serenity – that mirror waiting to be cracked, my flashy acrobatics with knives in the kitchen. How wrong we both were about each other, and how happy we have been. [End Page 18] To Speak in Tongues To speak in tongues is simply to follow desire out of the door of the mouth and into the open air – that place where language is seldom understood. They will bring doctors and interpreters who will shake their heads before they move on. Soon even words will fade, as stars must do at noon. There are no choices here.

Effects of deer fences in the conservation of Erythronium japonicum

Effects of deer fences in the conservation of Erythronium japonicum

Marking of deer fences to reduce frequency of collisions by woodland grouse

Recent studies of the effects of deer fences on tetraonids have concluded that fences are an important cause of mortality in woodland grouse. This 2-year study involving 16 sections of fences in the Scottish Highlands evaluates the effectiveness of making fences highly visible by using orange netting to reduce bird collisions with fences. A total of 437 collisions involving 13 bird species were recorded. Red grouse (Lagopus lagopus scoticus) formed 42% of all collisions, with black grouse (Tetrao tetrix) 29% and capercaillie (T. urogallus) 20%. Allowing for corpse removal by scavengers, an estimated 70% of red grouse and 29% of black grouse collisions were fatal. Black grouse and capercaillie both collided with 11 of the 16 fences at mean rates of 1.3 and 0.9 collisions km−1 year−1, red grouse collisions occurred at 13 fences, with a mean rate of 1.6 collisions km−1 year−1. Fewer grouse collisions occurred in the summer. Three quarters of black grouse collisions were by males. Collision rates were positively correlated with indices of black grouse and capercaillie abundance. Fence marking reduced capercaillie collisions by 64%, black grouse by 91% and red grouse by 49%. Although marked fences reduced capercaillie collision rates, they still remained an important cause of mortality. To conserve capercaillie, fences need to be removed altogether pending increased deer culls that would allow woodland regeneration without fences, or “grouse friendly” fences designed.

Behavioural responses of red deer to fences of five different designs

Capercaillie, a large species of grouse, are sometimes killed when they fly into high-tensile deer fences. A fence design which is lower or has a less rigid top section than conventional designs would reduce bird deaths, but such fences would still have to be deer-proof. The short-term behavioural responses of farmed red deer ( Cervus elaphus) to fences of five designs, including four that were designed to be less damaging to capercaillie, were measured. Five deer were located on one side of a fence with a larger group (20 animals), from which they had been recently separated, on the other. The efficacy of fences in preventing deer from the small group from rejoining the larger group was also recorded. In addition to a conventional deer fence (C) the four new designs were, an inverted “L” shape (L), a fence with offset electric wire (E), a double fence (D) and a fence with four webbing tapes above (W). Four replicate groups of deer were each tested for 3 days with each fence design. Deer paced the test fence line relatively frequently (a proportion of 0.09 scan observations overall) but significantly less when deer were separated by fences E or C compared to L, W or D (overall difference between fence types, P<0.001). Deer separated by fence E spent significantly more time pacing perimeter fences than deer separated by fences of other types (overall difference between fence types, P<0.01) but deer separated by fence C maintained a low level of fence pacing overall. Analysis of behaviour patterns across the first day and the 3 days of exposure suggested that the novelty of the test fences, rather than the designs per se, influenced the behaviour of the deer. Over the course of the study, no deer crossed either C or L. Three deer crossed E and two deer crossed both W and D. On this basis, field testing, particularly of fence L, would be a useful next step.