Deer Abundance Research Articles

Teeth osteometry as tool for studying social complexity: Evaluating white-tailed deer hunting sustainability at Nueva Esperanza, Colombia

Examining archaeological remains of animals may aid in understanding complex social interactions among pre-Hispanic societies and their access to protein sources. We study the agro-pottery groups that inhabited Sabana de Bogotá in Colombia during the Herrera (400 BC–200 AD), Early Muisca (200 AD–1000 AD) and Late Muisca (1000 AD–1600 AD) periods. White-tailed deer (Odocoileus virginianus; Zimmerman, 1780) was the most common protein in the diet of these communities. The relative abundance of white-tailed deer remains can be used as an index for the economies of pre-Hispanic societies. This study analyzes changes in prey proportion by age group to evaluate consumption sustainability. An osteometric analysis is used to determine the age of the deer. As entire jaws are infrequent in the archaeological record, this investigation proposes a methodology using measures of the height of the dental pieces that are more likely to be found in archaeological sites. We analyze 512 O. virginianus dental pieces obtained from the Nueva Esperanza site, and we present evidence of the three periods and a reference table that matches the height of each dental piece to the individual's age group. The osteometric analysis reveals that height measurements are a good indicator to establish the age class of each individual, which was assigned to one of four categories: infantile, young, adult, and old adult. The results suggest that deer hunting intensified as the population grew during the Early Muisca period; however, this did not entail resource scarcity.

Estimating Abundance of Siberian Roe Deer Using Fecal-DNA Capture-Mark-Recapture in Northeast China.

Simple SummaryEstimation of population abundance or density is necessary for managing deer populations. However, there is no estimation of Siberian roe deer (Capreolus pygargus) in the Lesser Xing’an Mountains, northeast China where the density of roe deer is much lower than that of European or North American populations. We used fecal-DNA capture-mark-recapture to estimate the abundance and density in Liangshui National Nature Reserve. We collected 422 fecal pellet groups during two sampling periods in 2016, identified them to be 77 individuals by the DNA microsatellite technique and estimated the abundance of roe deer to be 87 deer (80–112, 95% CI) using the Program CAPTURE. Density was estimated to be 2.9 deer/km2 (2.7–3.7, 95% CI). Our study estimated the roe deer population abundance by a feces-based capture-mark-recapture approach in northeast China, successfully demonstrating the applicability of this feces sampling method in monitoring deer populations in this area. It also contributes to the development of low-density deer population ecology and management.It is necessary to estimate the population abundance of deer for managing their populations. However, most estimates are from high-density populations inhabiting the forests of North America or Europe; there is currently a lack of necessary knowledge regarding low-density deer populations in different forest habitats. In this article, we used fecal DNA based on the capture-mark-recapture method to estimate the population abundance of Siberian roe deer (Capreolus pygargus) in Liangshui National Nature Reserve in the Lesser Xing’an Mountains, northeast China, where the deer population was found to be of a low density by limited studies. We used a robust survey design to collect 422 fecal pellet groups in 2016 and extracted DNA from those samples, generating 265 different genotypes; we thus identified 77 deer individuals based on six microsatellite markers (Roe1, Roe8, Roe9, BM757, MB25 and OarFCB304). With capture and recapture records of these 77 individuals, the abundance of roe deer was estimated to be 87 deer (80–112, 95% CI) using the Program CAPTURE. Using an effective sampling area which resulted from the mean maximum recapture distance (MMRD), we converted the population abundance to a density of 2.9 deer/km2 (2.7–3.7, 95% CI). Our study estimated the roe deer population abundance by a feces-based capture-mark-recapture approach in northeast China, successfully demonstrating the applicability of non-invasive genetic sampling in monitoring populations of deer in this area, which contributes to the development of low-density deer population ecology and management.

Seasonal and annual fluctuations of deer populations estimated by a Bayesian state-space model.

Deer overabundance is a contributing factor in the degradation of plant communities and ecosystems worldwide. The management and conservation of the deer-affected ecosystems requires us to urgently grasp deer population trends and to identify the factors that affect them. In this study, we developed a Bayesian state–space model to estimate the population dynamics of sika deer (Cervus nippon) in a cool-temperate forest in Japan, where wolves (Canis lupus hodophilax) are extinct. The model was based on field data collected from block count surveys, road count surveys by vehicles, mortality surveys during the winter, and nuisance control for 12 years (2007–2018). We clarified the seasonal and annual fluctuation of the deer population. We found a peak of deer abundance (2010) over 12 years. In 2011 the estimated deer abundance decreased drastically and has remained at a low level then. The deer abundance gradually increased from April to December during 2013–2018. The seasonal fluctuation we detected could reflect the seasonal migration pattern of deer and the population recruitment through fawn births in early summer. In our model, snowfall accumulation, which can be a lethal factor for deer, may have slightly affected their mortality during the winter. Although we could not detect a direct effect of snow on population dynamics, snowfall decrease due to global warming may decelerate the winter migration of deer; subsequently, deer staying on-site may intensively forage evergreen perennial plants during the winter season. The nuisance control affected population dynamics. Even in wildlife protection areas and national parks where hunting is regulated, nuisance control could be effective in buffering the effect of deer browsing on forest ecosystems.

Association of a threatened forest ungulate with the treeless herriza or Mediterranean heathland in southern Spain

The Andalusian roe deer (Capreolus capreolus var. garganta) is a medium-sized ungulate species whose unique biological features and protected, red-listed status have made it a highly prized hunting trophy. This game species is relatively abundant in forest ecosystems of southern Spain (province of Cádiz), at the European side of the Strait of Gibraltar. In this region, the herriza or Mediterranean heathland is a relatively abundant natural habitat of outstanding biodiversity value but frequently underappreciated due to its characteristic treeless feature. We searched available abundance data of roe deer in 182 hunting estates in the province of Cádiz during three four-year periods (2006–2009, 2010–2013, and 2014–2017) and obtained surface cover data of herriza habitat for each estate. We also collected data on other variables that could influence roe deer abundance, such as hunting estate surface area, and relative abundance of red deer (Cervus elaphus), a co-occurring game species. Then, using a spatially explicit approach, we explored the association of the Andalusian roe deer with the relative abundance of herriza and red deer in the hunting states. A significant, positive effect of the relative abundance of herriza in the hunting estates was found for the Andalusian roe deer abundance but not for the red deer. Although reasons for such positive association remain speculative, an ecosystem service potential of the herriza should be considered, not only to enhance the conservation of a protected, singular game species, but also to promote the conservation value of a unique natural habitat.

Tripartite Interactions among Ixodiphagus hookeri, Ixodes ricinus and Deer: Differential Interference with Transmission Cycles of Tick-Borne Pathogens

For the development of sustainable control of tick-borne diseases, insight is needed in biological factors that affect tick populations. Here, the ecological interactions among Ixodiphagus hookeri, Ixodes ricinus, and two vertebrate species groups were investigated in relation to their effects on tick-borne disease risk. In 1129 questing ticks, I. hookeri DNA was detected more often in I. ricinus nymphs (4.4%) than in larvae (0.5%) and not in adults. Therefore, we determined the infestation rate of I. hookeri in nymphs from 19 forest sites, where vertebrate, tick, and tick-borne pathogen communities had been previously quantified. We found higher than expected co-occurrence rates of I. hookeri with deer-associated Anaplasma phagocytophilum, and lower than expected rates with rodent-associated Borrelia afzelii and Neoehrlichia mikurensis. The prevalence of I. hookeri in nymphs varied between 0% and 16% and was positively correlated with the encounter probability of ungulates and the densities of all life stages of I. ricinus. Lastly, we investigated the emergence of I. hookeri from artificially fed, field-collected nymphs. Adult wasps emerged from seven of the 172 fed nymphs. From these observations, we inferred that I. hookeri is parasitizing I. ricinus larvae that are feeding on deer, rather than on rodents or in the vegetation. Since I. hookeri populations depend on deer abundance, the main propagation host of I. ricinus, these wasps have no apparent effect on tick populations. The presence of I. hookeri may directly interfere with the transmission cycle of A. phagocytophilum, but not with that of B. afzelii or N. mikurensis.

Florida Key Deer Abundance and Recovery Following New World Screwworm Infestation

An infestation of Cochliomyia hominivorax (New World Screwworm, hereafter Screwworm) was detected in the endangered Odocoileus virginianus clavium (Florida Key Deer) population in July 2016. We assessed the impact of this infestation on Florida Key Deer population abundance and recovery potential. We synthesized historical mortality and population data with new analyses including monitoring of Florida Key Deer mortalities and estimation of abundance on Big Pine Key and No Name Key (islands that support 75% of the Florida Key Deer population). We documented 135 Screwworm-related Florida Key Deer mortalities (∼9–20% of the total population) during the Screwworm outbreak (July 2016–January 2017). Most mortalities occurred in the adult male population, as Screwworm flies laid eggs on open wounds sustained from sparring during mating season. The Screwworm incident was contained prior to the 2017 fawning season, which prevented substantial negative impacts on females or fawns. Historical growth rates at similar population levels and sex ratios indicated that, absent other external variables (e.g., Hurricane Irma in September 2017), the population was likely to recover.

Seeing the Forest for the Deer: Plant Abundance and Diversity at the Gault Nature Reserve During a Spike in White-Tailed Deer

Background: Deer populations have been rising across North America for decades. At the Gault Nature Reserve in Quebec, half of which is open to the public, the population of white-tailed deer (Odocoileus virginianus) has exceeded the region’s carrying capacity, estimated to be 5 deer/km2, since 1996. Given that heavy grazing profoundly impacts forests, the purpose of this paper was to investigate the potential influence of white-tailed deer on plant abundance and diversity at the Gault Nature Reserve. We hypothesized that the abundance of deer, and by extension the effect of deer on vegetation, was negatively correlated with the proximity and frequency of human visitors on pedestrian trails. Our alternative hypothesis was that the effect of deer on vegetation was positively correlated with human disturbance, which is greater on the public side of the reserve.Methods: We recorded the abundance and diversity of vascular plants along 14 transects of increasing distance from pedestrian trails on the public and private sides of the reserve.Results: Contrary to our hypothesis, generalized linear models indicated that overall, plant abundance and diversity declined significantly as the distance from trails increased and that the effect of distance was significantly different on the two sides of the reserve. Pearson correlation tests revealed that there was not a significant correlation between distance and plant abundance and diversity on the public side, although there was a significantly negative correlation between these variables on the private side.Limitations: White-tailed deer were not directly studied, which limited the inferences that could be made about their influence on plant abundance and diversity.Conclusion: The distance from trails was a strong determinant of plant abundance and diversity on the private of the reserve, but not on the public side, possibly because trail edges generally receive more sunlight and because the increased number of trails on the public side may have confounded our results. Although we did not find support for our hypothesis, the influence of trail edges on plant communities was reinforced. Researchers should continue to monitor the influence of white-tailed deer and forest managers should be mindful of edge effects when making decisions.

Predictors of puma occupancy indicate prey vulnerability is more important than prey availability in a highly fragmented landscape

Habitat fragmentation represents the single greatest conservation challenge of the 21st century. This problem is particularly acute for large, obligate carnivores like pumas Puma concolor which have persisted in North and South America in the face of habitat fragmentation and other anthropogenic disturbances. Shrinking habitat and reduced connectivity mean that mapping habitat is increasingly important for species conservation in multiple-use landscapes. Previous work suggests that pumas occupy habitats where sufficient stalking cover and preferred prey are present, yet the intersection of these factors has rarely been assessed. Here we used data from 68 299 camera trap nights collected from 181 sites throughout the San Francisco Bay Area over a four-year period to identify key predictors of habitat occupancy for pumas and their primary prey (mule deer Odocoileus hemionus). Our goal was to determine whether pumas occupy habitats based on relative measures of prey availability (detection frequency), or ease of predation (density of stalking cover) and whether these predictors changed between seasons. Our results indicated that pumas primarily occupied forested habitats and did not choose habitats with abundant deer. Instead, pumas preferentially occupy habitats that facilitate their stalk and ambush hunting strategy, rather than higher prey densities, per se. The best occupancy models for mule deer indicated the importance of roads and shrub cover. However, even the best deer models performed poorly compared to the puma models, likely due to the ubiquity of mule deer in the region. Although prey density is a widely accepted correlate of habitat quality for many carnivores, our results suggest that structural elements of habitat may be a more important variable in predicting habitat use by large stalk and ambush predators like pumas, which has important implications for conservation success.

Use of Vegetation Monitoring and Professional Sharpshooting in White-Tailed Deer (Odocoileus virginianus) Management at Eagle Creek Park in Indianapolis

High white-tailed deer abundance at Eagle Creek Park (ECP) in Indianapolis necessitated active management to improve park habitat conditions. Significant deer impacts on local natural areas were first noted in the late 1990’s. Multiple years of deer browse monitoring, beginning in 2003, documented greatly impacted vegetation with heavy to severe browse damage in the park. After an initial managed hunt in 2014, population reductions have been accomplished exclusively at night by professional sharpshooters. Positive results are being evidenced through increasing pounds of venison per deer harvested and significant recovery of impacted vegetation communities.

Effects of culling white-tailed deer on tree regeneration and Microstegium vimineum, an invasive grass

Reduction of forest regeneration due to overbrowsing by white-tailed deer is a growing concern for land managers. Abundant deer can impede forest regeneration through direct predation on tree seedlings. Additionally high deer density can facilitate the establishment of a dense understory of browse tolerant plant species that shades seedlings and persists even in the absence of deer. In response to these challenges, land managers have sought to reduce deer herds to restore tree regeneration, but few studies have evaluated the effectiveness of this management. Our study took place in Catoctin Mountain Park, a US National Park Service unit with a history of high deer density. The park has been heavily invaded by Microstegium vimineum, an invasive grass that can completely cover the forest floor. Using permanent plots established prior to the start of deer management, we were able to assess the joint effects of deer culling and M. vimineum on tree seedling density. We found that tree seedling density increased in response to deer reductions. M. vimineum cover initially increased, but then decreased. Seedling densities were higher in plots with more M. vimineum cover, indicating that it did not form a recalcitrant understory that would suppress regeneration. However, eight years after deer management began, few tree seedlings were >30 cm tall, implying that it will be many years before they grow into the sapling stage. Our results indicate that deer culling can be an effective tool in restoring tree regeneration despite the presence of M. vimineum, but that success will require a long-term commitment.

Population responses of roe deer to the recolonization of the French Vercors by wolves

AbstractIn a context of changing carnivore populations worldwide, it is crucial to understand the consequences of these changes for prey populations. The recolonization by wolves of the French Vercors mountain range and the long‐term monitoring (2001–2017) of roe deer in this area provided a unique opportunity to assess the effects of wolves on this prey. Roe deer was the main prey of wolves in the west Vercors mountain range during this recolonization. We compared roe deer abundance and fawn body mass in two contrasted areas of a wolf pack territory: a central area (core of the territory characterized by an intense use by wolves) and a peripheral area (used more occasionally). Roe deer population growth rates were lower in the central area between 2001 and 2006, resulting in a decline in roe deer abundance. Roe deer abundance substantially dropped in the two study areas after an extremely severe winter but the abundance of roe deer in the central area facing with wolves was slower to recover and remained at lower abundance levels for 6 years. Fawn body mass was consistently lower in the central area, varied similarly as roe deer abundance, and was not influenced by weather conditions or red deer population abundance. Altogether, the effects of wolves on roe deer in the central area occurred during a 10‐year period following the establishment of wolves, through the interplay between wolf predation (before wolves started preying on red deer), harsh winter conditions and possibly naivety of prey to this recolonizing predator.

Seasonal surveillance of deer and horse flies (Diptera: Tabanidae), Gyeonggi province, Republic of Korea

• A total of 9985 tabanid flies comprising 2 subfamilies, 4 genera and 17 species. • The predominant species collected was Chrysops mlokosiewiczi . • The highest numbers of tabanids were collected from June-August. • A bimodal peak was observed for Chrysops mlokosiewiczi in June and late-July. Deer and horse flies, Family Tabanidae, are biological, mechanical, and potential vectors of approximately 27 viral, bacterial, and helminthic pathogens of veterinary and medical importance. Biting fly surveillance was conducted using New Jersey light traps and Mosquito Magnet® traps from May-October during 2015–2018 at eight sites (villages and US military installations and training areas) near/in the Demilitarized Zone and at a US military installation in southern Gyeonggi province, Republic of Korea. A total of 9985 deer and horse flies, comprising 4 genera and 17 species, were collected. The predominant species collected was Chrysops mlokosiewiczi (95.39%), followed by Chrysops suavis (1.48%) and Haematopota koryoensis (1.07%), while the remaining species accounted for only 2.06% of the specimens collected. A bimodal peak was observed for C. mlokosiewiczi in June and late-July, but not for the other two predominant species during the whole of the study period. This study provides and insight into ecological behavior and seasonal abundance of deer and horse flies in Gyeonggi province, Republic of Korea.

Demographic and genetic structure of a severely fragmented population of the endangered hog deer (Axis porcinus) in the Indo-Burma biodiversity hotspot.

The population of the globally endangered hog deer (Axis porcinus) has declined severely across its geographic range. Intensive monitoring of its demographic and genetic status is necessary. We examined the demographic and genetic structure of a small hog deer population in Keibul Lamjao National Park (KLNP), located on the western fringe of the Indo-Burma biodiversity hotspot for conservation planning. The distribution pattern of hog deer in the Park was derived based on the presence/absence of faecal pellets in 1 km × 1 km grids. We used double-observer distance sampling method to derive the hog deer abundance and population structure and compared with previous data to derive the population trend. We determined the genetic diversity of the population through microsatellite screening and bottleneck detection. The overall pellet density was 0.34 ± 0.02 pellets km-2 restricted to only 22.34 ± 0.20 km2 area of the park. The estimated density of the deer in the park was 1.82–4.32 individuals km-2. The population showed a declining trend from 2006–08 (p < 0.05, R2 = 0.916) with 8% annum-1 and an increasing trend from 2003–2018 (p < 0.05, R2 = 0.9304) with 10% annum-1. The adult male-to-female ratio and fawn-to-doe ratio were 36.2 ± 1.9 males per 100 females and 16.5 ± 0.4 fawns per 100 females, respectively. The molecular examination suggested that the mean number of alleles at 23 loci was 2.70 ± 0.18, the observed heterozygosity (Ho) ranged from 0.26 to 0.63 (mean 0.42 ± 0.02), the expected heterozygosity (He) ranged from 0.23 to 0.73 (χ = 0.51 ± 0.03), and the polymorphic information content (PIC) ranged from 0.2 to 0.67 (χ = 0.43 ± 0.03) indicating a moderate level of genetic diversity. Although no bottleneck in the population was observed, the loss of genetic diversity may affect the evolutionary potential of the species at the site by limiting the selection flexibility. Conservation planning coupled with scientific management regime will help in the long term persistence of the population in the region.

Habitat Use and Abundance of Island-Endemic White-Tailed Deer in Panama

Although white-tailed deer (Odocoileus virginianus) have been studied extensively, ecological information lacks for O. virginianus rothschildi, a subspecies endemic to Coiba Island, Panama. A combination of camera traps (n = 29) deployed during March–July 2015 and Royle–Nichols occupancy model were used to estimate the sex-related detection, habitat use, and abundance of unmarked deer. No covariates influenced detection of individual sexes, but detection of sexes combined was greater on wildlife trails than maintained human foot trails and negatively related to daily maximum temperature. Predicted abundance of sexes combined and females were greatest along an ecotone of secondary forest and feral fields, whereas male abundance was greatest at an ecotone of secondary and primary forest. Results corroborated the common mixed edge habitat use of O. virginianus, with likely partitioning of resources between sexes due to differing habitat needs. Although primary forest dominants Coiba Island, lesser use of this habitat suggests that it may provide poorer resources for deer, at least during the period of this study. Additionally, habitat use suggested potential avoidance of areas with greater feral livestock and tourist use. Further research is needed to understand the ecology of this endemic subspecies, including potential anthropogenic threats.

«Көлсай көлдері» ұлттық табиғи паркіндегі еліктің қазіргі жағдайы, қоныс аударуы

The article presents the results of a one-time registration of roe deer conducted from 2011 to 2020. The census began in 2011 together with the staff of the Institute of Zoology on 13 routes. Census of roe deer was carried out by methods of census of the main hunting and commercial and rare species of animals in Kazakhstan. The counts were carried out in spring and autumn. This article presents the results of the 13 routes by sex, age, abundance and habitat of roe deer in 2020. In general, the number of roe deer in the Kolsai Lakes National Natural Park is currently 350-500 individuals. According to park inspectors, such fluctuations in the number of roe deer are associated with unfavorable weather conditions and heavy snowfall in some years, the migration of deer outside the national park, as well as the presence of wolves, etc. An increase in the number of predators also affects. This figure can be seen from the results of the roe deer survey in 2011-2020.

Estimating Deer Populations Using Camera Traps and Natural Marks

ABSTRACTDespite the ubiquity of camera traps in wildlife monitoring projects, the data gathered are rarely used to estimate wildlife population demographics, a critical step in detecting declines, managing populations, and understanding ecosystem health. In contrast to abundant white‐tailed deer (Odocoileus virginianus) in the eastern United States, black‐tailed deer (Odocoileus hemionus columbianus) in the western United States have declined over the past several decades. We tested whether passively operating camera traps can be used to quantify population characteristics for black‐tailed deer. We used images of naturally occurring physical characteristics of deer to develop movement and activity data and inform a Bayesian spatial mark‐resight model that estimates deer abundance, density, sex ratio, ratio of fawns to adult females, and home range size. We developed the model to account for the effect of attractants (bait) on encounter rate. We placed 13 cameras on all known water sources of a private ranch in California and provided bait once a month in front of each camera. Over 9,000 visits occurred between 24 May 2012 and 21 January 2013, and we identified 50 individual deer from ear notches or antler characteristics. We estimated density at 7.7 deer/km2 in summer and 8.6 deer/km2 in fall. In the summer, home ranges were 2.3 km2 for females and fawns and 16.8 km2 for males. Home ranges constricted slightly in fall. We estimated a sex ratio of 12.5 males/100 females, and a ratio of 47.0 fawns/100 adult females. Bait increased baseline encounter rates (visits/week) by 3.7 times in summer and 4.95 times in fall. We found slightly higher densities of deer in our study area compared to other recent studies in more mountainous areas of California, and lower male:female sex ratios. This approach shows that commonly deployed camera traps can be used to quantify population characteristics, monitor populations, and inform harvest or habitat management decisions. © 2019 The Wildlife Society.

Landscape-scale effects of homesteads, water, and dingoes on invading chital deer in Australia’s dry tropics

AbstractIdentifying landscape features and processes that facilitate the persistence of populations is particularly important for invasive mammal species, because it can focus management interventions on relatively small areas. We used camera traps to test predictions concerning the relative abundance of invading chital deer (Axis axis) on seven cattle ranches in northern Australia: that abundance of chital deer would be highest near permanent water and near homesteads, and that dingoes (Canis dingo) reduce abundance of chital deer. Distance from the nearest homestead determined deer abundance (as indexed by images per camera-day), with negligible abundance &gt; 4 km from homesteads. In contrast, distance from homestead did not predict abundance of feral pigs (Sus scrofa), macropods, or dingoes. Abundance of chital deer also declined with increasing distance from water, as did feral pig abundance. There was no relationship between either macropod or dingo abundance and distance to water. The abundance of chital deer was unaffected by dingo abundance, but 75–100% of dingo scats collected within 1 km of homesteads contained chital deer. The high abundances of chital deer near homesteads are likely due to increased food quality or quantity, or protection from dingoes, but these hypotheses require further testing. We conclude that homesteads and permanent water are important determinants of the distribution and abundance of invasive chital deer in northern Australia (i.e., they are “invasion hubs” for this species). Our results suggest that, during the dry season, managers should survey for and attempt to control chital deer within 4 km of homesteads and within 3 km of water.

Long-term variation in white-tailed deer abundance shapes landscape-scale population dynamics of forest-breeding birds

Over-browsing by white-tailed deer impedes forest regeneration, alters floristic and structural attributes of stands, and reduces biodiversity. Although numerous exclosure experiments have demonstrated negative impacts of deer on songbirds at small spatial scales, the effects of deer on avian communities at large spatial and temporal scales remains poorly understood. We integrated data from the Breeding Bird Survey with historic information on deer abundance in a multi-species hierarchical model to assess spatio-temporal relationships between deer and bird abundances across the state of Pennsylvania between 1981 and 2015. Our results provide evidence of strong links between deer and both avian functional groups and individual species, depending upon the extent each relied upon particular forest strata. Specifically, species that forage or nest near the ground were more negatively affected by deer than canopy-associated species. Likewise, mature-forest species were more sensitive to deer than successional-forest species or habitat generalists. With only a few exceptions, species-level responses to deer were consistent with group-level effects. Given the diverse suite of spatio-temporal stressors impacting migratory songbirds throughout their annual cycle, it was not surprising that long-term population trends of focal species were not significantly associated with deer abundance. Our findings, however, provide evidence that deer play an important role in songbird community structure, as mediated by the reliance of individual species upon particular forest strata and, as such, should be considered within the context of forest bird conservation.

Red oak seedlings as indicators of deer browse pressure: Gauging the outcome of different white-tailed deer management approaches.

After decades of high deer populations, North American forests have lost much of their previous biodiversity. Any landscape‐level recovery requires substantial reductions in deer herds, but modern societies and wildlife management agencies appear unable to devise appropriate solutions to this chronic ecological and human health crisis. We evaluated the effectiveness of fertility control and hunting in reducing deer impacts at Cornell University. We estimated spring deer populations and planted Quercus rubra seedlings to assess deer browse pressure, rodent attack, and other factors compromising seedling performance. Oak seedlings protected in cages grew well, but deer annually browsed ≥60% of unprotected seedlings. Despite female sterilization rates of >90%, the deer population remained stable. Neither sterilization nor recreational hunting reduced deer browse rates and neither appears able to achieve reductions in deer populations or their impacts. We eliminated deer sterilization and recreational hunting in a core management area in favor of allowing volunteer archers to shoot deer over bait, including at night. This resulted in a substantial reduction in the deer population and a linear decline in browse rates as a function of spring deer abundance. Public trust stewardship of North American landscapes will require a fundamental overhaul in deer management to provide for a brighter future, and oak seedlings may be a promising metric to assess success. These changes will require intense public debate and may require new approaches such as regulated commercial hunting, natural dispersal, or intentional release of important deer predators (e.g., wolves and mountain lions). Such drastic changes in deer management will be highly controversial, and at present, likely difficult to implement in North America. However, the future of our forest ecosystems and their associated biodiversity will depend on evidence to guide change in landscape management and stewardship.

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 &gt;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.