Deer Density and Forest Regeneration, Biodiversity
Deer can be too many, too few, or just enough for healthy forests March 31, 2012 NRS Research Review, No. 16, Spring 2012 
 ... they found that deer population levels at or below 20 per square mile allowed undergrowth to recover. The study surprised scientists, though, when there was some regrowth even at very high deer densities.... when deer populations were reduced to just-right densities (from about 28 to about 15 deer per square mile in that particular landscape) populations of wildflower indicator species such as trilliums and Canada mayflower started to recover ... one species of small tree/shrub, pin cherry, that had become overabundant at the lowest levels of deer density (10 per square mile in that study). They soon realized that this phenomenon was early evidence of such a thing as too few deer. Pin cherry, a shrubby cousin of black cherry (a desirable lumber tree), can outcompete other species when highly abundant...

Cumulative effects of chronic deer browsing and clear-cutting on regeneration processes in second-growth white spruce stands M Barrette, L Bélanger, L De Grandpré, JC Ruel - Forest Ecology and Management, 2014
.. the cumulative effect of chronic deer browsing and recent clear-cutting on regeneration processes of mature second-growth white spruce stands has not yet been evaluated. ... Our results indicate regeneration failure in both ecosystems, which can be explained by a lack of suitable rotten logs for sufficient establishment of white spruce seedlings... We propose shelterwood cuttings that create nurse logs should be investigated to maintain white spruce stands without planting...

Impact of ungulate exclusion on understorey succession in relation to forest management in the Intermountain Western United States, Oregon, BK Pekin, BA Endress, MJ Wisdom, BJ Naylor… - Applied Vegetation Science, 2014
...  managed sites displayed more early succession species, such as annual forbs and annual graminoids, while unmanaged sites were dominated by late-succession species such as shrubs, subshrubs and trees. Species richness, particularly of annuals, was strongly reduced when ungulates were excluded from managed sites, and to a lesser extent from unmanaged sites for some perennial plant species. Species diversity decreased to a slightly greater extent with ungulate exclusion at managed sites. Species dominance was not influenced by ungulate exclusion....

Overabundant ungulates in French Sologne? Increasing red deer and wild boar pressure may not threaten woodland birds in mature forest stands  M Baltzinger, A Mårell, F Archaux, T Pérot, F Leterme… - Basic and Applied Ecology, 2016
... Generally, increasing deer browsing pressure did not have any negative effect on woodland birds in mature forest stands with a developed canopy, and did not result in lower shrub cover. Most previous studies documenting a negative effect of browsing on birds focused on young forest stands where overstory vegetation was scarce. Our results suggest that the impact of ungulate pressure on forest birds may decrease with forest stand age...

...  Vertebrate seed dispersers are often heavily hunted, resulting in reduced seed movement for many species and a shift in community composition to favor those plants dispersed by small animals and abiotic means. Timber species with large seeds and fleshy fruit are at particular risk for dispersal and recruitment failure. Hunting also alters granivore communities, resulting in increased predation on species favored by insects and small rodents, and changing the spatial template of seed predation, with detrimental effects on many timber species. Large vertebrate herbivores decline with hunting pressure, resulting in the modification of plant competitive interactions. This is disadvantageous to several traits that are common among timber trees, including relatively slow growth and high wood density...

... Twelve taxa had optima at zero to low herbivory intensity (losers), while 25 species had optima at intermediate to high herbivory intensity (winners), with most species peaking at intermediate intensity. The growth forms young trees and dwarf shrubs were losers, and ferns, forbs, bryophytes and juvenile trees were winners. At the functional trait level, woody species were the only losers, whereas clonal, prostrate and non-palatable species were more abundant towards the high end of the herbivory gradient...

Highstead Foundation: Getting data on your backyard eco-system September 1, 2015 Connecticut, The Redding Pilot
... Just beside the Redding Country Club ...  a focus on long-term ecological studies .... one on deer impact that has been running for 17 years... Some exotic species benefit from deer browsing and some do not. Japanese barberry does better in areas where deer can graze, but burning bush and oriental bittersweet do better protected... , there is greater diversity of native shrubs inside a deer exclosure... greater diversity of native herbs outside the deer exclosures...

Direct and indirect effects of white-tailed deer in forest ecosystems,  Forest Ecology and Management Volume 181, Issues 1–2, 3 August 2003, Pages 165–176
Thomas P Rooney, , Donald M Waller
As reported in Figure 2, the density of yellow birch seedlings measured in the forest ecosystem fell off dramatically when the deer density fell much below 18 deer per square mile (about 7 deer per square km) or when deer density was much above about 44 deer per square mile (about 17 deer per square km).

... During the year when culling was conducted, the number of sika deer caught on camera decreased around the center of the study site where the culling was conducted and the number of browsed seedlings decreased. During the year following culling, the cumulative number of browsed seedlings was very similar to that in the year before the culling, while the same low number of sika deer was caught on camera. These results indicate that the effects of deer culling resulted in decreased levels of sika deer appearance and browse damage for more than 1 year and for several months, respectively.

Optimum density of sika deer for tree seedling survival  H Itô, T Hino, H Takahashi - The Journal of Wildlife Management, 2014
... We estimated optimum deer density was 9.5 deer/km2 (24.6 deer per square mile) when floor leaf biomass of the dwarf bamboo was 0.15 kg/m2.... These results suggested that in this system, managing deer density at moderate levels might be more effective from a forest regeneration perspective than the complete exclusion of deer...

Landscape-scale vegetation patterns influence small-scale grazing impacts EK Moore, AJ Britton, G Iason, J Pemberton… - Biological Conservation, 2015
... Understanding the distribution of herbivory is of great importance to planning the conservation management of plant communities. Control of wild and domestic large herbivore populations at large scales is commonly used to manipulate their impacts. However, the relationship between large scale population density and local impacts is often weak as the spatial layout of plant communities, and the herbivores' preferences for them, can drive the herbivores' habitat use... Herbivore density was only weakly correlated to grazing impacts...

PJ Bellingham, SJ Richardson, NWH Mason… - … Ecology and Management, 2016
... Deer have been introduced to forests worldwide as non-native invasive species. Red deer (Cervus elaphus scoticus) were introduced to New Zealand in 1851, became abundant throughout its forests, then their populations declined to current, typically low densities... We conclude that red deer, at current low densities, affect the regeneration of the dominant canopy tree of these forests slightly, but at levels that are unlikely to prevent canopy replacement...

... deer can indirectly benefit hardwoods by reducing competition with palatable forbs (ch. 3). In general, these results show that fire suppression in central Texas oak-dominated woodlands is causing a shift not to more mesic-adapted species, as observed in the eastern US, but to J. ashei, which is at least as xeric-adapted as oak, a process I termed 'juniperization'.

.... Our findings highlight the indirect effects of white-tailed deer on the growth of adult individuals of Q. rubra in a way opposite of what would be expected from previous studies based on immature or understory tree populations. We suggest the increased growth of adult trees in the presence of deer may be explained by increased nutrient inputs through deer fecal and urine deposits and the alteration of the competitive environment belowground through the reduction of understory vegetation by browsing. Underscoring the ecological and demographic importance of adult trees in forest ecosystems, results from this study suggest the direct and indirect effects of deer on mature trees should not be overlooked.

Indirect Effects of a Keystone Herbivore Elevate Local Animal Diversity, KATHERINE R. GREENWALD,*, LISA J. PETIT, THOMAS A. WAITE The Journal of Wildlife Management Volume 72, Issue 6, pages 1318–1321, August 2008
     Abstract: We quantified indirect effects of white-tailed deer (Odocoileus virginianus) on ground-dwelling herpetofauna and invertebrates in Cuyahoga Valley National Park, Ohio, USA. We placed cover boards at 12 sites, each consisting of a 10 × 10-m fenced (exclosure) plot and an unfenced (control) plot. Periodically, during May-December 2004 and May-September 2005, we counted salamanders, snakes, and a variety of invertebrate taxa. Salamander, snake, and gastropod abundance as well as invertebrate richness (no. of species or higher level taxa) were higher in control than exclosure plots. Our findings suggest that management actions taken to regulate deer densities could have the unintended effect of reducing local animal diversity.

... Overall, we predict that debarking of small trees living in heavy snow areas should occur even at low deer densities (<10 deer/km2). Browsing on dwarf bamboo should occur at intermediate deer densities (10–30 deer/km2), while debarking of thick trees living in low snow areas should occur only at high deer densities (≥30 deer/km2). Our study shows that debarking and browsing on understory vegetation are appropriate indices for evaluating deer impacts on forest ecosystems, but that tree size, snow depth, and the type of understory vegetation should also be considered...

Some plants evolve tolerance to deer December 4, 2014 New York, Cornell Chronicle 
... An experiment with 26 populations of orange jewelweed (Impatiens capensis), a common wetland native plant, found that historically browsed populations tolerated being eaten by deer far better than historically protected plant populations...

Effects of wildlife management in national parks on its populations - Where to go?  Dominik Dachs, Research in Protected Areas, 2013  
... "The “landscape of fear” is widely ignored as a key natural process in our ecosystems. Without anti-predation behavior, ungulate species are kept in a system that is far from being natural. For protecting the natural processes in national parks without predators, the question is not if population control is maintained, but rather how it is done (CROMSIGT et al. 2013). Regular hunting is a very poor substitute for imitating the “landscape of fear” normally created by large carnivores (PROFFITT et al. 2009) and contains great risks to the objectives of the national parks. Human hunters can select by unnatural behavioral criteria (MILNER et al. 2007) or have negative genetic effects (COLTMAN et al. 2003).

Exclusion of large herbivores: Long-term changes within the plant community M Newman, FJG Mitchell, DL Kelly - Forest Ecology and Management, 2013
...  Fencing to conserve biodiversity is increasingly used as a management tool, so the long-term impacts of large herbivore removal requires investigation. The objective of this research is to investigate the effect of large herbivore exclusion on vegetation, through time, using empirical long-term vegetation data collected over ∼40 years...With total removal of large herbivores from the oak woodland ecosystem, this study has identified significant changes in ground flora composition and abundance, and a general homogenisation of the vegetation community with increasing time since large herbivore removal. Large-scale long-term fencing of oak woodlands should be replaced by large herbivore management programmes, in order to ensure the conservation of diverse woodland ecosystems.

Spatiotemporal variation in deer browse and tolerance in a woodland herHR Prendeville, JC Steven, LF Galloway - Ecology, 2014
 ... To investigate broad-scale patterns of deer herbivory, we examined the frequency and reproductive consequences of deer browse over three years in 17 populations of Campanulastrum americanum spanning the latitudinal extent of its range. Even though deer are overabundant throughout the range of C. americanum, we found spatiotemporal variation in deer browse frequency (0-0.96, mean 0.46) and its effects on plant reproductive success. The four southernmost populations experienced high levels of herbivory ... Across many populations and years, average fitnesses of browsed and uneaten plants were similar, suggesting that plants are tolerant to browse. However, since large plants have greater reproductive success and are more likely to be browsed, tolerance may be influenced by plant size...

... We sampled understorey vegetation in former clearcut areas where density of white-tailed deer (Odocoileus virginianus) was manipulated (3.9-31.2 deer/km2) for 10 years (1979-1990) and stands experienced ambient deer density (ca. 10-12 deer/km2) for the next 20 years (1990-2010) to determine whether initial deer-density treatments still influenced understorey vegetation in 30-yr old, closed-canopy forests.
Stands initially (1979-1990) exposed to higher deer densities had ca. five times higher fern cover and a third the seedling and forb cover in 2010, as well as significantly lower angiosperm species density, compared to stands initially exposed to lower deer densities...

... A massive undertaking to protect white pine seedlings was underway on Saturday at Boulder Lake as a team of volunteers spent the day bud capping acres of reforested trees there. The white pine buds are a favorite meal for deer, so capping is meant to prevent that. The effort was just another step in Minnesota Power's Rajala Woods initiative to provide for industry and natural benefit with new, healthy forests...

...Deer (Cervidae) cause considerable damage to forest plantations, crops, and protected habitats. The most common response to this damage is to implement strategies to lower population densities ... On the landscape scale, damage level was negatively related to availability of forage in the field and shrub layers and proportion forest, but was not related to any of the relative deer density indices. Increasing alternative forage may thus decrease damage and thereby reduce conflicts. Additionally, the proportion of forest in the landscape affects damage levels and should thus be considered in landscape planning and when forecasting damage risk...

Moose in southern New England? August 12, 2013  Connecticut, The Redding Pilot
 ... Highstead ecologist Ed Faison and colleagues are studying how both species — separately and collectively — are changing the region’s forests. And they are finding that moose and deer do not eliminate tree species but rather slow the rate of tree growth... The researchers believe their study in northern Connecticut and central Massachusetts is the first on the effects of combined deer and moose browsing in North America...

Study aims to end Rock Creek Park deer hunt August 6, 2013 Washington, D.C., WTOP
... The National Park Service has said the deer hunt is needed because the animals are eating so many native plants that the park can't recover...  a study by Dr. Oswald Schmitz, director of the Yale Institute for Biospheric Studies, came to a different conclusion. "... deer are not inhibiting forest regeneration in Rock Creek Park," Jessica Almy, an attorney representing opponents of the hunt ...

National Park Service Conducts Mass Slaughter of Deer Last Night in Washington DC's Rock Creek National Park January 7, 2014 Save Rock Creek Deer News Release
... Dr. Oswald Schmitz, Director of Yale University's Institute for Biospheric Studies, analyzed the scientific studies relied upon by the NPS for removing the deer and found that the NPS did not analyze its own data properly. Dr. Schmitz found, unequivocally, that the approximately 300 deer are NOT preventing the Park's forest from regenerating. Dr. Schmitz found that the most serious threat to the Park's native vegetation is invasive non-native plants -- a problem that the NPS has known about for more than 20 years but has refused to address until recently.  In fact, so little native vegetation remains because of the take-over by exotic plants that native deer must leave the Park to find native food to eat..

Effects of large native herbivores on other animals CN Foster, PS Barton, DB Lindenmayer - Journal of Applied Ecology, 2014
... Most empirical studies of herbivory effects compared only two levels of herbivory (76%), and meta-analysis showed that very high densities of herbivores, when compared with very low densities, had mostly negative effects on other animal species. These negative effects were usually attributed to changes in the quantity and/or structure of vegetation. Only 24% of papers studied animal responses across a gradient of herbivore densities; and non-linear responses to herbivory, as well as responses to low and moderate herbivore densities, remain poorly understood.
     The literature also was dominated by short-term studies (76% sampled animal responses for 2 years or less) and there was a high incidence of confounding factors among studies (38% of studies). In addition, many studies used only coarse metrics to assess effects (e.g. only 33% of studies assessed species composition) and few included community-level synthesis (only 31% of studies reported results from more than one animal class)....

JM O'Reilly-Wapstra, BD Moore, M Brewer, J Beaton… - … Ecology and Management, 2014
... we examine the genetic basis of recovery of Scots pine saplings following browsing by red deer ...  These data, matched with our finding of no negative relationships between any recovery traits, indicate that Scots pine is quite robust to once-off browsing events by deer. We suggest that at the sapling stage, Scots pine do not employ resistance as a strategy against deer, but tolerate deer browsing to counteract the negative impacts of herbivory. Hence, the use of recovery traits as a management tool to mitigate the negative impacts of browsing is an option worthy of further investigation.

... In this study we use a regional-scale design with 51 sites in four boreal forest regions of Norway, to investigate the influence of cervid herbivory on the physical and ecological structure of field layer vegetation.... We found that the height of the field layer and the abundances of individual species were most susceptible to change following short-term cervid exclusion across different forest types and cervid species. Total vegetation density and vascular plant diversity did not respond to cervid exclusion on the same time scale. We also found that the field-layer vegetation in clear-cut forests used by moose was more susceptible to change following cervid exclusion than mature forests used by red deer, but no strong evidence that the response of vegetation to herbivore exclusion varied with productivity. Our study suggests that the parameters that respond to cervid exclusion are consistent across forest types, but that the responsiveness of different forest types is idiosyncratic and hard to predict.

... 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 non-trophic indirect effects, particularly leaf disturbances and the potential impact of other large consumers as well (e.g., turkeys).

Study tracks deer impact on pest plants October 24, 2011 New Zealand, ABC Online, By Fidelis Rego 
Early findings from a project at a dam on southern Queensland's Darling Downs suggest feral deer may be helping reduce pest plants. University of Queensland researchers ..."We know for example that deer eat prickly pear because we've seen deer teeth marks in prickly pear that could not be eaten by kangaroos," Professor Murray said. "Now the question is how much of that eating is actually important in reducing the impact of prickly pear and equally lantana.

Modelling browsing of deer on beech and birch in northern Germany  M Bobrowski, B Gillich, C Stolter - Forest Ecology and Management, 2015
... Our results indicate that the availability of stands exclusively consisting of birch (preferably young birch) might decrease the proportion of browsed beeches in neighbouring stands, or even favour the selection of birch over beech for food, which would consequently lead to increased future beech regeneration...

White-tailed deer (Odocoileus virginianus) positively affect the growth of mature northern red oak (Quercus rubra) trees RW Lucas, R Salguero-Gómez, DB Cobb, BG Waring… - Ecosphere, 2013
... Understanding and predicting the effects of deer (Cervidae) on forest ecosystems present significant challenges in ecosystem ecology. Deer herbivory can cause large changes in the biomass and species composition of forest understory plant communities, including early life-cycle trees (i.e., seedlings and saplings).... Our findings highlight the indirect effects of white-tailed deer on the growth of adult individuals of Q. rubra in a way opposite of what would be expected from previous studies based on immature or understory tree populations. We suggest the increased growth of adult trees in the presence of deer may be explained by increased nutrient inputs through deer fecal and urine deposits and the alteration of the competitive environment belowground through the reduction of understory vegetation by browsing. Underscoring the ecological and demographic importance of adult trees in forest ecosystems, results from this study suggest the direct and indirect effects of deer on mature trees should not be overlooked.

Old-growth forest floor richness increases with red deer herbivory intensity  SJ Hegland, MS Lilleeng, SR Moe - Forest Ecology and Management, 2013
... We recorded the ungulate herbivory intensities on the island Svanøy in west Norway across 10 years and related this to the present plant richness of an old-growth pine-forest system, recording all plant species groups of the forest understory... Does increased herbivory by red deer harm boreal forest floor richness?  We examine this by relating a herbivory intensity gradient to plant species richness.  Increasing herbivory intensity enhance richness except at artificially high herbivory levels.  Low-growing species groups benefit at the expense of taller growing woody species.  Boreal forest floor richness may benefit from relatively high red deer herbivory intensity.


...  We examined the effects of cattle, American elk, and mule deer on aspen regeneration and recruitment along gradients of forest composition and physiographic conditions in 3 National Forests of Utah, USA... We found that 60% of the sites we surveyed had low ungulate activity and good aspen regeneration, 32% were intermediate use sites that warrant additional monitoring, and 8% of sites showed high ungulate use that exhibited aspen regeneration failure and lack of recruitment where targeted management is recommended. We conclude that ungulate impacts in aspen forests should be considered on a site by site basis ...

Logging can be beneficial, especially given forest fire suppression

Timbering in state forests vital to wildlife and economy November 29, 2016 Ohio, Cincinnati.com
... The Ruffed Grouse Society ... strongly supports timber harvesting in Ohio’s publicly owned forests...  the creation of new growth, early successional forests or young brushy woods... supports populations of deer and wild turkey ...

Variability in Seed Production Can Improve Sugar Maple Production in High Deer Density

... Our results suggest seed masting in sugar maple can bolster cohort recruitment success that otherwise would virtually (or completely) fail when severe impact from deer browsing is combined with other typical early life-stage mortality risks, e.g., from drought, neighborhood competition, and persistent overhead canopy shade...
The paradox of long‐term ungulate impact: increase of plant species richness in a temperate forest O Vild, R Hédl, M Kopecký, P Szabó, S Suchánková… - Applied Vegetation Science, 2016
... Contrary to our expectations, our long-term data showed that artificially high ungulate densities substantially increased plant species richness. Apparently, the establishment of ruderal herbs was supported by frequent disturbances and ungulate-mediated dispersal. At the same time, species richness of non-ruderal plants did not change, probably because ungulates hindered the regeneration of woody species and maintained an open forest canopy. In conclusion, high ungulate density led to the spread of ruderal species, which in turn strongly contributed to the observed shift towards nutrient-richer conditions and taxonomically more homogenous communities...

Deer call over protected forests July 23, 2014 United Kingdom, MailOnline
... A decades-long study of national parks in Ireland .. Researcher Dr Miles Newman said deer grazing at the correct level is highly important for the conservation of native oak woodlands... Exclusion of large herbivores: Long-term changes within the plant community was published in the journal Forest Ecology and Management

... “In a world where there were no deer at all, we might lose some our plant diversity,” said ecologist Susan Cook-Patton of the Smithsonian Environmental Research Center, co-author of an April 8 Proceedings of the Royal Society B study describing the findings ... they found that the high-diversity plots actually did much better when deer had grazed in them. According to Cook-Patton, that’s because deer appetites prevented hardy, fast-growing species from proliferating...

     Positive interactions between herbivores and plant diversity shape forest regeneration SC Cook-Patton, M LaForgia, JD Parker - Proceedings of the Royal Society B: …, 2014
... One experiment factorially manipulated plant diversity (one versus 15 species) and the presence/absence of deer (Odocoileus virginianus). We found that mixtures outperformed monocultures only in the presence of deer. Selective browsing on competitive dominants and associational protection from less palatable species appear responsible for this herbivore-driven diversity effect....

Row after claim exotic trees threaten more ancient woodland than deer January 5, 2017 United Kingdom, Herald Scotland
... a new analysis of the Native Woodland Survey of Scotland, undertaken by Forestry Commission Scotland, shows deer are not the main problem and species like Sitka Spruce may be even more damaging...

Response of native versus exotic plant guilds to cattle and elk herbivory in forested rangeland  BK Pekin, MJ Wisdom, CG Parks, BA Endress… - Applied Vegetation Science, 2015
... Cattle and elk have variable effects on different plant guilds at managed vs unmanaged forest stands. Overall, cattle grazing tends to have a larger impact on herbaceous plant guilds at managed stands, while elk grazing tends to have a larger impact on woody plant guilds at unmanaged stands. However, in contrast to findings from other ecosystems, grazing only has a minor impact on exotic plant dynamics in our study area, and cattle grazing does not favour exotic plants any more than grazing by elk or ungulate exclusion...

Setting the record straight on Alliance for the Wild Rockies September 13, 2015 Montana, Independent Record 
... Appropriately sized logging projects with openings next to cover and with snags left in place benefit deer, elk, moose, birds, small mammals and other species. Logging today isn’t what it was in the 50s and 60s. Regulations limit the size and location of projects, mandate streamside buffer zones and require sufficient numbers of live and dead trees be left standing to augment regeneration and habitat...

Here's What Goes on Inside a Forest When a Massive Wildfire Hits September 15, 2015 Atlas Obscura
... grazers and foragers such as deer, elk, and bison have been evolving with fire for some 10,000 years. Long before there were such things as a logging industry, forest management plans, and fire science theory, fire was nature’s way of refreshing and regenerating forests. Fires were allowed to burn until the rains or snows snuffed them out ...

Influence of white‐tailed deer population density on vegetation standing crop in a semiarid environment BL Crider, TE Fulbright, DG Hewitt, CA Deyoung…Texas, - The Journal of Wildlife …, 2015... 
Diet selection theory predicts that selective foraging by white-tailed deer (Odocoileus virginianus) may reduce palatable and nutritious plants when high-quality food resources are available or deer densities are high... Variable and limited rainfall had a more pronounced effect on variation in vegetation standing crop than white-tailed deer foraging regardless of food resource availability or deer density. Vegetation responses were more complex than can be predicted by traditional theory on diet selection in part because of the pronounced effect of variation in rainfall on vegetation standing crop ...

... "We found that deer disperse seeds to a much greater extent than we thought. This is good news, since many grassland plants are endangered when natural pastures disappear. Seed dispersal through deer could contribute to biodiversity in the Swedish agricultural landscape", says Alistair Auffret from the Department of Physical Geography and Quaternary Geology. 

M Nevřelová, J Ružičková - Ekológia (Bratislava), 2015
... The main objective of this research was an assessment of ungulates, impact on woody species, evaluation of damage forms and bark renewal phases of affected woody plants. The study area is located in western Slovakia ... After the mild winter in 2014, the majority (93.7%) of previously affected Fraxinus excelsior trees in the forest locality had only old damages with renewed bark in different phases of regeneration. In the non-forest locality, 96% of young Fraxinus excelsior, damaged in the winter of 2013, shot up new sprouts. The mortality of affected trees was minimal (4−5%).

... survival of seedling transplants of 15 native understorey plants in 5 forests in New York State. Earthworm biomass was negatively correlated with survival of 12 of 15 species. We found no interactive effect of deer and earthworms, but did find a positive, non-consumptive effect of deer on Geranium maculatum and P. virginianum survival. Deer and earthworm presence/absence indirectly influenced other trophic levels: earthworm presence increased the likelihood of insect attack, and deer exclusion increased the likelihood of rodent attack disturbance of transplants...

Hunting and Forest Regeneration in State Parks July 7, 2014 Indiana, Purdue Agriculture News
...a Purdue Study ...  a 17-year-long Indiana Department of Natural Resources policy of organizing hunts in state parks ... Herbs such as asters, violets and goldenrods increased from about 20 percent to 32 percent cover, and percent cover of grasses rose from 1 to 3 percent. Tree seedlings jumped from about 2 percent to about 13 percent of total plant cover ... research article ... 

P Hanberry, BB Hanberry, S Demarais, BD Leopold… - Plant Ecology & Diversity, 2013
      The abundance of white-tailed deer (Odocoileus virginianus) in the eastern United States has escalated during the twentieth century, potentially impacting plant communities.  Methods: We measured understorey plant cover and biomass five years after excluding deer from mature forests of three ecological regions in Mississippi, USA. We extended the significance of P values to 0.10 to detect developing impacts... Conclusions: Exclosure treatment effects on canopy cover and species richness in two regions indicated limited negative impacts from deer foraging. A time frame of more than five years may be required for exclusion to allow recovery of vegetation, even with relatively open canopies and a long growing season.

Effects of Deer Settling Stimulus and Deer Density on Regeneration in a Harvested Southern New England Forest  [PDF] KJ Barrett, OJ Schmitz - International Journal of Forestry Research, 2013
... Deer density and browse impact had a relationship with thermal settling stimulus for summer and fall months, and deer density had a relationship with browse impact in the winter on woody plants. We conclude that thermal settling stimulus is an important predictor for deer density and browsing impact.

Old-growth forest floor richness increases with red deer herbivory intensity  SJ Hegland, MS Lilleeng, SR Moe - Forest Ecology and Management, 2013
... We recorded the ungulate herbivory intensities on the island Svanøy in west Norway across 10 years and related this to the present plant richness of an old-growth pine-forest system ...  Increasing herbivory intensity enhance richness except at artificially high herbivory levels.  Low-growing species groups benefit at the expense of taller growing woody species.  Boreal forest floor richness may benefit from relatively high red deer herbivory intensity.

The effects of deer herbivory and forest type on tree recruitment vary with plant growth stage  MN Bugalho, I Ibáñez, JS Clark - Forest Ecology and Management, 2013
... We assessed how deer herbivory and forest-type affected the diversity of seedlings and saplings of dominant tree species in a temperate forest of Eastern USA, during four consecutive years. Fenced and unfenced plots were established .. The diversity of seedlings and saplings was significantly affected by inter-annual variation of tree recruitment but not by deer herbivory or forest type. Herb cover was reduced for more than fourfold in unfenced hardwood plots. Results show that inter-annual variation of recruitment, herbivory and forest type can combine to shape the composition of tree seedlings and saplings...

Southwestern CT: A 5 Year Update January 4, 2013 Connecticut, E. Faison. Highstead, Redding, CT 
     The towns of Redding and Ridgefield CT began deer hunting on several town preserves in 2006.  In 2007 Highstead established forest monitoring plots in these preserves and nearby unhunted properties to document any changes to forest understories resulting from deer management.  These plots were resampled for the first time in 2012, and the results are presented here. 
     From 2007 to 2012, tree seedling (≥30 cm<2.5 cm diameter) density increased in both hunted and unhunted properties (Fig. 1), whereas species richness of tree seedlings (the number of different tree seedlings per plot) changed little from 2007 to 2012 in either management category.   [tree density increased more in unhunted properties]

Deer-Forest Study November 18, 2013 Pennsylvania, PGC News
... several deer in Pennsylvania are wearing GPS radio collars that can be controlled via text messages... the Game Commission has placed collars on thousands of Pennsylvania deer. Through such monitoring, researchers have learned things such as 70 percent of yearling bucks will disperse miles from where they were born, and have better understood harvest rates of antlered and antlerless deer during the hunting seasons...  The study also looks at the impact deer have on forest regeneration, a phenomenon that has been studied for decades but now can be measured at a higher level of detail... their browsing in the forest understory often makes deer an easy target when it comes to assigning blame for lagging forest regeneration – even when other factors could be responsible.  The new study will help ensure that, in cases where deer aren’t responsible for lagging regeneration, they won’t be blamed for it.

The effects of deer browsing on species richness and density of an exclosure. D Rodriguez, E Burns, J Greenfield, T Bulthuis - 2015
... The forested area we surveyed at the University of Michigan Biological Station in Pellston, Michigan, had a deer exclosure built 17 years ago, which allowed us to compare the effects of deer browse over time with the exclosure area as a control. We recorded groundcover species, tree species density and tree diameter at breast height (DBH) both inside and outside of the deer exclosure. Trees that were browsed outside the exclosure were also identified and recorded. We did not find any statistical difference in woody or herbaceous ground cover species density and richness...

Deer-Forest Study September 20, 2013 Pennsylvania, PGC News
... Since 2006, when the Game Commission began using measures of forest regeneration, it has recognized that deer are not the only factor affecting regeneration. To better understand the effect of deer on the forest, these other factors must be investigated. Consequently, the Deer-Forest Study will explore how forest management activities (i.e., timber harvesting, prescribed fire, herbicide treatments, etc.) can influence deer impacts on the forest.

...The estimated deer density in the park will be 49 deer per square mile (260 deer) after fawns are born this spring. Although still above the plan’s initial target level of 31-35 deer per square mile, this represents a significant reduction from the estimated 241 deer per square mile (1,277 deer) present in 2009...  National Park Service staff has documented native species seedlings that had not been just a few years ago, including maple, ash, oak, black gum, hickory, cherry, and sassafras...

VL Fox, KR Frederick, RJ Kelly, EM Meadows - Natural Areas Journal, 2014
... We assessed the effects of deer on forest understory vegetation in the park using exclosures and control plots and estimated the size of the deer population in the park using infrared digital game cameras. There were almost no changes in forest understory vegetation during the first four years after the exclosures were established. The estimated population size of deer in the park ranged from 46 to 66 deer per km2... We conclude that deer are having minimal effects on forest understory vegetation in the park at this time ..

How to Obliterate Deer in Federal Parks October 15, 2013  Virginia, Counter Punch
...  in Manassas, where more than 1,600 deer are targeted ... the Service is promoting a shooting-contraceptive “bundle”; methods ...  By shooting most deer before they become mature, the government is creating groups of only very young animals... researchers at Ohio State University and the National Park Service itself are challenging the science that suggests deer ravage ecosystems. High deer populations promote biodiversity ... Evidence shows plants’ vital uptake of carbon increases where both herbivores and carnivores exist...

... This evidence comes from exclusion experiments where animals such as moose and deer were prevented from grazing on young trees. In exclusion zones, woody vegetation flourishes... herbivores, which fed on sprouting trees and shrubs, played a key role in maintaining open landscapes. Once they disappeared, dense woody vegetation became much more abundant ... [read the research article article, video below]


Increased Biodiversity in Grasslands
Herbivores + light = more plant biodiversity in fertilized grasslands March 10, 2014 National Science Foundation 
... The scientists' hypothesis was that grassland plant species losses caused by eutrophication (overfertilization) could be offset by the increased light availability that results when taller plants are munched down by herbivores like deer and sheep.  This "trimming" by herbivores ultimately lets in more light, fueling increased plant growth.  The experiment, replicated in 40 grasslands on six continents, demonstrated that the researchers had it right...


Very High Deer Density Can Negatively Affect Forest Regeneration, Increased Diversity
...  In 2005, we established six 15×15 m fenced enclosure ... Browsing resulted in significantly decreased overall species richness (but higher diversity), reduced seed bank abundance, relatively more short-lived species (annuals and biennials), and fewer native species... [The multiyear study was conducted on Cornell land near Freese Road in Ithaca, where the deer density is about 39 animals per square kilometer – about 100 deer per square mile]

Endozoochory by the Persian fallow deer reintroduced in Israel: species richness and germination success   R Zidon, H Leschner, U Motro, D Saltz - Israel Journal of Ecology & Evolution, 2016
... From fecal samples, we found that more than 30 species of plants germinated from the deer pellets. Four of the more common species are considered as ruderal. Of the trees, carob (Ceratonia siliqua) seeds were the only intact seeds found in the fecal samples. We found that ingestion by the deer has a positive effect on expediting the germination of carob seeds ...

Positive Impact of Deer Browsing on Soybean Crops
The impacts of white‐tailed deer browsing and distance from the forest edge on soybean yield JE Rogerson, JL Bowman, EL Tymkiw, GM Colligan… - Wildlife Society Bulletin, 2014
... During 2003–2006 in Delaware, USA, we investigated where and when browsing was most intense within crop fields and subsequently had the greatest effect on yield of soybeans at an estimated deer density of 21 deer/km2.... We found that deer browsing increased yield, possibly because browsing increases branching of individual plants, and thus the number of bean pods. We also found that the distance from the forest edge affected yield, but independently of deer browsing. Deer damage to soybeans, at a deer density of 21 deer/km2, may be more of a perceptual issue and the use of a chemical repellant would not be justified. ...

Measuring Regeneration
   Assessment of regeneration can be time-consuming and costly. Often, foresters look for ways to minimize the cost of doing inventories. One potential method to reduce time required on a plot is use of percent cover data rather than seedling count data
to determine stocking. Robust linear regression analysis was used in this report to
predict seedling count data from percent cover data based on 3,800 plots on which
both count and cover data were collected. Results showed very poor relationships of
cover data to seedling counts overall. The weakest relationships were found in plots
that had received a shelterwood seed cut without any other regeneration preparation
in the past. The better relationship came from plots where competition was reduced
through herbicide application and shelterwood seed cutting. Immediately following
herbicide application, when total seedling numbers were lowest, the relationship of
cover to counts was best, with r-squared values as high as 0.8 for black birch, and
between 0.4 and 0.6 for the smallest black cherry and red maple. These numbers
quickly declined as seedlings developed. Cover data cannot reliably serve as a
surrogate for seedling counts.


... Damages in the forest stands are permanently present because man with its management practice changed and imposed living conditions for deer game. Occurrence and intensity of damages by red deer did not increase, but slightly declined for 0.4% in last twenty four years. Regulations in the hunting ground and proper management by creating surface convenient for pasture, sufficient and quality food and feeding sources, facilitate setting up a balance between forest management and size of red deer population in the hunting ground...

...  to understand the effects of roe deer impact on the forest development, I used a forest development model (LANDIS-II) to simulate 200 years of forest development, considering harvesting and roe deer impact. I found that both disturbances influence species richness, abundance, and forest structure. Roe deer impact does not significantly affect harvesting yield, and the disturbances combined do not seem to represent an hazard for forest functionality.

Gulf Islands plant evolves to protect itself from deer May 27, 2015 British Columbia, news.ubc.ca
... seablush, a flowering plant native to the endangered Garry oak ecosystem of the Pacific Northwest, grows differently depending on the presence or absence of deer.  On islands free of deer, seablush grows 70 to 120 centimetres tall with branches high off the ground. On islands where deer are present, seablush grows 10 to 20 cm tall with branches low to the ground, making it less visible to herbivores...

Management of forest regeneration in boreal and temperate deer–forest systems: challenges, guidelines, and research gaps [PDF] Quebec, Ecosphere, 2016
... forest management practices that address adequately this issue, however, remains scarce and challenging because (1) large herbivores are both a resource and a source of disturbance; (2) the management of forests and ungulate populations remains largely disconnected in practice; and (3) we still lack a good understanding of the role of critical factors, especially deer densities, vegetation attributes, and their interactions, on the magnitude of browsing damages on forest regeneration...

Although Deer Are Often Blamed for Problems in the Northeast Forests, This Article Discusses the Two Most Significant Factors Suspected by Ecologists:  Climate Change and Land Use
... In Pennsylvania, as along the entire eastern seaboard, forests have been expanding. But eastern forests are also in trouble, showing signs of stress ... not everyone agrees with her that climate change is the real problem here.  A recent report by a Penn State researcher says the stresses on eastern forests have more to do with 500 years of land use trauma inflicted by European settlers...

Other Results

Deer account for long-term forest change January 7,2015 Agri-View 
... A research group led by Donald Waller, a professor of botany at the University of Wisconsin-Madison, used a pair of strategies to look at the ecological impact of deer. First, in 2000-2001 he resurveyed 62 sites across northern Wisconsin and Michigan that were first studied by former UW-Madison Professor John Curtis and his students in the 1950s. [the study starts in a period of low deer population and ends when the deer population peaked] ...

After almost 20 years of using controlled hunts to reduce deer density in Indiana state parks, a study is conducted to see if there is any effect.  They find more under story as a result, U.S. Forest Service research at the top of the page finds that too much under story reduces forest regeneration.
Woody regeneration response to over a decade of deer population reductions in Indiana state parks LH Jenkins, BD Murray, MA Jenkins… - Journal of the Torrey …, 2015 - BioOne
...  Species richness increased significantly in all three height classes in parks, but only in the > 200 cm class in reference areas. Density of Fraxinus americana and Acer saccharum increased greatly in the < 50 cm and 50–200 cm height classes in both state parks and reference areas. [not much change for 20 years of killing deer]

Understanding landowner intentions to create early successional forest habitat in the northeastern United States  AA Dayer, RC Stedman, SB Allred, KV Rosenberg… - Wildlife Society Bulletin, 2015
     Early successional forest habitat (ESH) and associated wildlife species in the northeastern United States are in decline. One way to help create early successional forest conditions is engaging private forest landowners in even-aged forest management because their limited participation may have contributed to declines in ESH for wildlife species ...

The Fire Ecology

South Carolina DNR Official Sees Smokey Bear as Threat to Prescribed Burns March 23, 2016 Firefighter Nation
... The use of prescribed fire as a land management tool has deep and ancient roots in South Carolina's heritage... Prescribed fires help restore and maintain vital habitat for wildlife, including bobwhite quail and other grassland birds, wild turkeys, white-tailed deer, gopher tortoises and red-cockaded woodpeckers...

Prescribed burn to benefit wildlife habitat at Perryville Battlefield March 23, 2016 Kentucky, Central Kentucky News
... Burning fields may not sound like a good thing, but it makes for a high-quality habitat, stimulating the growth of valuable grasses and wildflowers, Brunjes said, and it benefits birds and game, including quail, rabbits, deer, turkeys, bluebirds, grasshopper sparrows, meadowlarks and more...
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Deer Friendly,
May 9, 2017, 7:22 AM