Lowland Conifer Research Articles

Woodland caribou calving fidelity: Spatial location, habitat, or both?

Individuals that isolate themselves to give birth can use more than one strategy in choosing birth sites to maximize reproductive success. Previous research has focused on the consistency in the use of the same birth-site across years (i.e., spatial fidelity), but individuals alternatively may use similar habitat conditions across years (i.e., habitat fidelity). Using GPS telemetry, we determined whether woodland caribou expressed spatial or habitat fidelity during calving, and evaluated intrinsic and extrinsic factors associated with expressing either type of fidelity. We identified 56 individuals with ≥2 putative birth events, via a movement-based model, across northern Ontario between 2010 and 2014. Individuals were classified as expressing (1) spatial fidelity by comparing sequential calving locations to a random spatial distribution of available calving locations, (2) habitat fidelity using a logistic use model compared to a null (intercept only) model, (3) no fidelity (neither criterion met), or (4) both spatial and habitat fidelity (both criteria met). Across all individuals, 37% expressed no fidelity (36 of 98), 15% expressed only spatial fidelity (15 of 99), 35% expressed only habitat fidelity (34 of 98), and 14% expressed both spatial and habitat fidelity (14 of 98). Older individuals were more likely to express spatial fidelity, whereas lower availability of upland and lowland conifer forests without linear features increased the probability an individual expressed habitat fidelity. Our results indicate that managing for caribou calving needs to consider protecting both specific, known birthing sites, but also broad-scale areas of preferred habitat for calving. Understanding the mechanisms that influence caribou expressing calving fidelity, and associated fitness costs, is crucial for the conservation of the species.

Plantation clear‐fell patches benefit heathland arthropods

Abstract Plantation forests constitute a significant amount of the wooded area in many parts of the globe. However, the extent of biological provision conferred by plantation forest depends on regional conservation priorities and biogeographical context. Here, we evaluate the arthropod biodiversity in a chronosequence of pine plantation (clear‐felled, 1, 3, 5, 7, 9, 13, 21‐years) in the largest lowland conifer forest in the UK. We compare the assemblage within 37 plantation stands and eight important open habitat remnants in a formerly heathland dominated region. We also assess the configuration and potential isolation of ephemeral open early growth stage habitat across a 60‐year plantation rotation. Carabid and spider assemblages changed throughout the sampled chronosequence. In the early growth stages (1–7 years) before canopy closure, arthropod assemblages contained many individuals and species associated with dry‐open habitats, greater numbers of rare species than closed canopy plantation and had similar composition (non‐metric multidimensional scaling) to heathland samples. Early growth stages and heathlands primarily differed in the additional presence of generalist species in the plantation. Species associated with woodland increased in abundance as the plantation aged, but remained far less numerous than dry‐open or generalist species. The spatial distribution of young growth stages across the rotation cycle was significantly clustered in the early and late rotation phases. Plantation landscapes often support high species richness but we highlight their value for vulnerable heathland biodiversity early in the rotation cycle. To increase plantation value regional conservation priorities should be supported with appropriate consideration of growth stage configuration across the full rotation.

Soil change and broadleaf tree growth 10 years after wood ash and brash co-application to a clearfelled lowland conifer site in Britain

Abstract Wood ash use, to raise pH and replace nutrients lost through forest harvesting, is well regulated in Scandinavia and Canada, but not yet in the UK. This experiment applied granulated wood ash from mixed tree thinnings to a lowland clay mineral soil at ~2.3 t ha−1 dose rate, after clearfell of western hemlock (Tsuga heterophylla (Raf.) Sarg.). With brash (~56 t ha−1 dry weight) as N resource, a 4 × 4 matrix of ash only, ash + brash, brash only and control treatments were planted with oak seedlings (Quercus robur L.). Soil survey was undertaken before ash application and followed over 10 years. By year 2, self-sown grass was dominant in the control and ash plots, and birch (Betula pendula, Roth.) was present across all treatments by year 4. In year 10, oak height was 25–29 per cent greater in brash and ash + brash plots, with DBH increased >20 per cent over the controls. Birch DBH was greater by 30 per cent in brash plots but was over 50 per cent in the ash + brash plots. Foliar concentrations of Ca, K and P significantly increased with ash addition in both oak and birch, as Al, Mn, Fe and Cr decreased. Soil pH (CaCl2) was reduced in all treatments in year 2 likely due to nitrification, during organic matter and needle breakdown, but recovered 8 years later to be significantly highest in ash and ash + brash plots. Mg, K, Ca, Na, Ba and S concentrations were higher in ash plot soils, but soil organic matter, total carbon and total nitrogen declined due to mineralization and uptake by grass and trees. Wood ash addition did not significantly increase heavy metal concentrations in either soil or foliage. In the long term, wood ash aided soil recovery and promoted tree growth in combination with the brash – it could be beneficial for tree growth after thinning/coppicing on heavy mineral soils, with the prerequisite of an existing ground cover. Aim To quantify the effects of wood ash and brash addition over time to soils and tree growth after conifer clearfelling on a lowland clay soil site.

Habitat and climatic associations of climate-sensitive species along a southern range boundary.

Climate change and habitat loss are recognized as important drivers of shifts in wildlife species' geographic distributions. While often considered independently, there is considerable overlap between these drivers, and understanding how they contribute to range shifts can predict future species assemblages and inform effective management. Our objective was to evaluate the impacts of habitat, climatic, and anthropogenic effects on the distributions of climate-sensitive vertebrates along a southern range boundary in Northern Michigan, USA. We combined multiple sources of occurrence data, including harvest and citizen-science data, then used hierarchical Bayesian spatial models to determine habitat and climatic associations for four climate-sensitive vertebrate species (American marten [Martes americana], snowshoe hare [Lepus americanus], ruffed grouse [Bonasa umbellus] and moose [Alces alces]). We used total basal area of at-risk forest types to represent habitat, and temperature and winter habitat indices to represent climate. Marten associated with upland spruce-fir and lowland riparian forest types, hares with lowland conifer and aspen-birch, grouse with lowland riparian hardwoods, and moose with upland spruce-fir. Species differed in climatic drivers with hares positively associated with cooler annual temperatures, moose with cooler summer temperatures and grouse with colder winter temperatures. Contrary to expectations, temperature variables outperformed winter habitat indices. Model performance varied greatly among species, as did predicted distributions along the southern edge of the Northwoods region. As multiple species were associated with lowland riparian and upland spruce-fir habitats, these results provide potential for efficient prioritization of habitat management. Both direct and indirect effects from climate change are likely to impact the distribution of climate-sensitive species in the future and the use of multiple data types and sources in the modelling of species distributions can result in more accurate predictions resulting in improved management at policy-relevant scales.

Effects of stand age, tree species, and climate on water table fluctuations and estimated evapotranspiration in managed peatland forests

Lowland conifer forests dominated by black spruce (Picea mariana) and tamarack (Larix laricina) typically occur in peatlands in the boreal North American forest with near-surface water tables throughout the year. These forests are ecologically and economically important resources that may be impacted by climate change. However, information characterizing effects of forest disturbance, such as even-aged harvest on water table dynamics is needed to evaluate which forest tree species cover types are most hydrologically susceptible to even-aged harvest and changes in precipitation. We used a chronosequence approach to evaluate water table fluctuations and evapotranspiration across four stand age classes (<10, 15–30, 40–80, and >100-years old) and three distinct forest cover types (productive black spruce, stagnant black spruce, and tamarack) for a period of three years in Minnesota, USA. In general, there is limited evidence for elevated water tables in the younger age classes; the <10-year age class had no significant difference in mean weekly water table depth compared to the older age classes across all cover types. Estimated actual daily evapotranspiration (ET) generally agreed with the water table observations, with the exception of the tamarack cover type where ET was significantly lower in the <10-year age class. Productive black spruce sites that are 40–80-years old had higher evapotranspiration, and lower water table, possibly reflecting increased transpiration associated with the stem exclusion stage of stand development. Tamarack in the 40-80-year age class had higher water tables but no difference in ET compared to all other age classes, indicating that other external factors are driving higher water tables in that age class. To evaluate susceptibility to changing climate, we also assessed the sensitivity and response of water table dynamics to pronounced differences in growing season precipitation that occurred across study years. In general, tamarack forests are more sensitive to changes in precipitation compared to the two black spruce forest cover types. These findings can inform expected responses of site hydrology for a range of precipitation scenarios that may occur under future climate and be used by forest managers to evaluate hydrologic impacts of forest management activities across lowland conifer forest cover types.

Habitat associations of breeding conifer-associated birds in managed and regenerating forested stands

Forests are often affected by management that could influence demographics of breeding and post-breeding birds that reside within. Numerous studies have focused on immediate effects from management on wildlife soon after forestry treatment (e.g., 0–5 years); however, fewer studies have examined changes in focal species abundance over longer durations as a forest regenerates after disturbance. We examined how forest management influenced 18 conifer-associated birds during breeding and post-breeding over the forest regeneration period in a landscape dominated by forestry. To achieve this, we combined avian detection data from point count surveys conducted in lowland conifer and mixed-wood forests in Maine, New Hampshire, and Vermont with Bayesian distance-removal models and an information-theoretic framework. We estimated abundance and associations with seven common forestry treatment categories applied at the stand scale, years-since-harvest (YSH; 5–120 + ), and seven vegetation variables measured within stands. Forestry treatment categories and YSH were poor predictors of abundance. Of 14 species with models having good-fitting statistical distributions while including forestry treatments and YSH as covariates, no species had associations. Of 13 species with models having good-fitting statistical distributions while including vegetation covariates, 12 had important associations between abundance and vegetation variables. Each vegetation variable was associated with abundance of some species, irrespective of the forestry treatment in which the site occurred, including spruce-fir tree composition (seven species), tree basal area (six species), midstory cover (five species), live crown ratio (three species), shrub cover (three species), tree diameter at breast height (two species), and shrub composition (one species). In a companion study, several species assemblages were associated with vegetation variables (i.e., spruce-fir tree composition, tree basal area, and tree diameter at breast height) that were associated with YSH and forestry treatments, suggesting that some forestry treatments may indirectly influence avian abundance when certain vegetation outcomes are achieved. Our results suggest that managers could target species-specific vegetation outcomes rather than more broadly categorized forestry treatment types when managing for individual focal species because of large variations in vegetative outcomes across stands within a forest treatment category. Our study informs management and conservation of biodiversity in regions such as the Atlantic Northern Forest in North America where commercial forestry is the dominant human land use.

Linking functional diversity, trait composition, invasion, and environmental drivers in boreal wetland plant assemblages

AbstractQuestionsA range of landscape and local environmental factors, including invasion, interact with species functional diversity and trait composition to shape biodiversity patterns and ecosystem function of wetlands. A trait‐based, mechanistic understanding of community assembly holds promise for wetland conservation, but this has been rarely examined across scales. We examined: (a) the relative influence of climate, landscape matrix, and local physicochemistry on invasion intensity and functional diversity in boreal wetland plant assemblages; and (b) the ecological traits linked to these environmental factors.LocationOne hundred fifty‐three wetlands across the Boreal Forest of Alberta, Canada.MethodsWe used data on invasion intensity, using two terrestrial invaders (Sonchus arvensis and Cirsium arvense), and environmental factors at local and landscape levels. We used eight traits from 366 vascular plants to assess functional diversity and invasion responses to environmental gradients (generalized linear models) and individual species trait–environment relationships (community‐weighted mean redundancy analysis, fourth‐corner analysis).ResultsLandscape matrix and the degree of invasion were the primary drivers of functional diversity, while invasion intensity was driven by physicochemistry and functional diversity. Community trait–environment patterns clearly separated wetlands by invasion status. Uninvaded wetlands were surrounded by lowland conifers and composed of stress‐tolerant associated traits, while invaded wetlands contained high levels of disturbance and traits associated with high resource availability and reproduction rates. This division was further supported by individual trait–environment relationships.ConclusionsLandscape matrix was the dominant driver of functional diversity and composition pattern, while the local physicochemistry and surrounding land‐cover matrix helped explain invasion. Our analysis revealed some of the mechanistic relationships shaping plant community assembly across boreal wetlands, information that can help resource managers identify, predict, and alleviate possible threats from landscape anthropogenic disturbances to wetland ecological integrity.

Applications of Integrating Wildlife Habitat Suitability and Habitat Potential Models

ABSTRACTAssessment of habitat suitability provides natural resource managers with insights on the quality and spatial distribution of habitat for wildlife species. However, habitat suitability models only provide information on current habitat parameters, and do not consider changes in habitat due to forest succession and disturbances. Habitat potential models have been developed by identifying habitat types and their successional trajectories to provide insights on how landscapes change with time. We developed habitat suitability index (HSI) models and habitat potential models for elk (Cervus elaphus nelsoni) on public and private lands within the Michigan elk range (1,220 km2) in northeastern lower Michigan, USA. Our objective was to demonstrate how integration of habitat suitability and habitat potential models can provide spatiotemporal insights on wildlife habitat. When constructing public‐lands models, we used state forest compartment‐inventory data to identify cover types important to elk, and assigned suitability values (0 = low, 1 = high) to each cover type for elk life requisites (i.e., spring food, winter food, winter thermal cover). Additionally, we modified suitability values based on stand conditions acquired from state forest inventory records (e.g., stand size, percent canopy closure, age of aspen [Populus spp.]). For our private‐lands models, we used satellite imagery to classify cover types and assigned suitability values to cover types for each elk life requisite, and modified values based on percent canopy closure for winter thermal cover. Elk habitat potential was modeled by delineating habitat types by overlaying digital spatial data layers (soils, land‐type associations, vegetation) and identifying successional trajectories using habitat classification guides and literature. We assigned suitability values to each habitat type for life requisites at early to late successional stages. The highest suitability value of each habitat type's successional stage determined the habitat potential for each habitat type. Our winter thermal cover HSI model indicated several large areas (5–13 km2) of high suitability (i.e., lowland conifers) in the southern third of our study area. Our winter food HSI model indicated a heterogeneous arrangement of high suitability areas (hardwoods, upland conifers, aspen) throughout our study area. Our spring food HSI model indicated few areas of high suitability (openings) primarily on private lands. Our habitat potential models indicated high potential for each elk life requisite across the elk range. Comparisons between current elk habitat suitability and habitat potential identify key areas where managers can maximize management efforts for elk in Michigan. Areas determined to have high habitat potential (e.g., mature aspen stands) may become focus areas if they currently have low habitat suitability. Conversely, managers can avoid committing resources to areas with low habitat potential. Integrating habitat suitability and potential models provides insights on how wildlife habitats may respond to forest succession, land management practices, and disturbances, and ultimately help natural resource professionals prioritize and meet a diversity of wildlife management goals. © 2021 The Wildlife Society.

Historical decline of genetic diversity in a range-periphery population of Spruce Grouse (Falcipennis canadensis) inhabiting the Adirondack Mountains

Isolation can affect genetic structure of populations near the edge of a species’ geographic range by reducing gene flow and allelic diversity, resulting in greater among-population differentiation. Spruce Grouse (Falcipennis canadensis), which are restricted to the boreal forest biome of North America, persist in small, disjunct lowland conifer patches at the southeastern extent of their range in the Adirondack Mountains of New York. This isolated peripheral population has declined since the early twentieth century and is considered highly vulnerable to extirpation. We examined haplotype diversity of mitochondrial control region sequences, comparing modern Spruce Grouse populations sampled from 2004 to 2013 in the Adirondacks and Algonquin Provincial Park, ca. 250 km to the northwest. Genetic diversity in the modern Adirondack population sample was very low compared to our smaller sample from Algonquin Park (three haplotypes vs seven). The modern Adirondack population shared no haplotypes with birds sampled from Algonquin, and these two populations are highly differentiated today (Fst = 0.632). We obtained shorter control region sequences from 18 museum specimens collected in the Adirondack from 1881 to 1986, in which we found six haplotypes, including five no longer found in the Adirondack Region. Some haplotypes that were once found in both regions have been lost from the Adirondacks as that population has declined demographically and shrunk geographically, indicating that the current differentiation is partly the result of these losses; when all 18 historical samples of Adirondack Spruce Grouse are included in the analysis, Fst between Adirondacks and Algonquin drops to 0.359. Haplotype diversity in Adirondack specimens collected prior to demographic decline (1881–1905, n = 10) was h = 0.778 compared to h = 0.245 in the modern Adirondack population, an over a three-fold decrease over period of ca. 130 years. These findings suggest that conservation measures that include supplementation of individuals from more diverse populations may restore genetic diversity in the Adirondack population to levels that existed a century ago.

Temporal changes in avian community composition in lowland conifer habitats at the southern edge of the boreal zone in the Adirondack Park, NY

Climate change represents one of the most significant threats to human and wildlife communities on the planet. Populations at range margins or transitions between biomes can be particularly instructive for observing changes in biological communities that may be driven by climate change. Avian communities in lowland boreal habitats in the Adirondack Park, located at the North American boreal-temperate ecotone, have been the focus of long-term monitoring efforts since 2007. By documenting long-term changes in community structure and composition, such datasets provide an opportunity to understand how boreal species are responding differently to climate change, and which habitat characteristics may be best able to retain boreal avian communities. We examined three specific questions in order to address how well current biological communities in Adirondack boreal wetland habitats are being maintained in a changing climate: (1) how do trends in occupancy vary across species, and what guilds or characteristics are associated with increasing or decreasing occupancy? (2) how is avian community composition changing differently across sites, and (3) what distinguishes sites which are retaining boreal birds to a higher degree than other sites? Our analysis revealed that (1) boreal species appear to exhibit the largest changes in occupancy among our study locations as compared to the larger avian community, (2) dynamics of community change are not uniform across sites and habitat structure may play an important role in driving observed changes, and (3) the particular characteristics of large open peatlands may allow them to serve as refugia for boreal species in the context of climate change.

Spruce grouse decline in maturing lowland boreal forests of New York

Forest succession affects species that rely on specific successional stages of forest development as core habitat. The spruce grouse (Falcipennis canadensis) is a mid-successional boreal forest obligate declining in population size and range extent in the northeastern United States. We evaluated habitat occupancy from 2002 to 2006 and we contrasted spruce grouse habitat use at multiple spatial scales to determine if advancing succession of boreal forest influenced the species’ distribution in New York from 2002 to 2012. We detected grouse at less than half (n=13) of forest patches occupied from 1976 to 1987 and at one previously undocumented patch suggesting in aggregate a 71% reduction in extent of area occupied. Spruce grouse kernel home ranges reflected a 13× greater selection for short (<6m) lowland conifer over tall (>6m) lowland conifer, a 4.5× greater selection of short lowland conifer over upland conifer, and an 8× greater selection for ericaceous vegetation over tall lowland conifer. Within home ranges, bird radiolocations revealed an 8.5× greater selection for short lowland conifer over upland conifer, a 6.6× greater selection of short lowland conifer over ericaceous vegetation, a 5× greater selection of tall lowland conifer over upland conifer, and a 4× greater selection of tall lowland conifer over ericaceous vegetation. Occupied forest patches were 75% closer to other occupied patches than were formerly occupied patches. Moreover occupied patches were 10% larger, they were characterized by 90% less Sphagnum spp., 5× greater ericaceous shrub cover, 34% greater tree density, 71% less live vegetation >6m tall, 8% less coniferous shrub cover, and contained about half of the live vegetation from 4 to 6m above the ground. Trees were 20% younger in occupied versus formerly occupied patches (x¯=43.37 [SE=41.82–44.95] versus 51.87 [SE=50.95–52.81], respectively). We also observed 17% greater importance value (i.e., IV=100×[relative basal area×relative density×relative frequency]/3) of tamarack (Larix laricina) and a 43% less balsam fir (Abies balsamea) importance value suggesting a decreased component of earlier successional species in occupied versus formerly occupied patches. We conclude that reduced size and greater isolation of remaining habitat patches as well as forest succession have contributed to spruce grouse declines in New York, processes that could be reversed through establishment of mid-successional forest patches near remaining grouse-occupied habitats.

Habitat use by spruce grouse in northern Wisconsin

Spruce grouse (Falcipennis canadensis) habitat use varies widely across their range and is not well-understood near the southern extent of their range. Threats to conifers from climate change make understanding habitat use at the southern edge of the range increasingly important. We obtained habitat information on 55 radiocollared spruce grouse in northern Wisconsin, USA from 16 May 2007 to 10 July 2012. Black spruce (Picea mariana) and tamarack (Larix laricina) were the most common habitat components. Some of our findings differed from previous reports, including little use of eastern hemlock (Tsuga canadensis) or northern white cedar (Thuja occidentalis), use of tamarack in summer more than any other tree species, and winter roosting and feeding in red pine (Pinus resinosa), especially where jack pine (P. banksiana) was not available. Male display points contained fewer small broadleaf saplings (x¯ = 652 trees/ha), greater percent conifer (87%), more jack pine (x¯ = 148 trees/ha), and denser canopy (x¯ = 65% closure) compared with random points (3,288 small broadleaf saplings/ha, 70% conifer, 7 jack pine/ha, and 51% closure). Dense ground cover was the best predictor of brood points, although brood points were similar to random points. Winter flock points were typified by dense canopy cover (x¯ = 76% closure) and more jack pine (x¯ = 407/ha). Management should be focused on areas with extensive conifer, especially near black spruce–tamarack swamps. Retaining or establishing closed-canopy coniferous uplands, especially jack pine stands 15–30 years old, adjacent to lowland conifer swamps should benefit spruce grouse populations. © 2013 The Wildlife Society.

Setting priorities for wildfires suppression policy in Greece, using a relation between yearly burned areas and recovery time

In the Mediterranean region, fire is a natural factor, which contributes in the shaping of landscape and the preservation of a high degree of biodiversity. However, often repeated burning has negative impacts on the forested landscapes. When the processes of natural or artificial regeneration are efficient and the fire frequency is sufficiently low to enable the recovery of vegetation, recovery time T can be used as a tool for setting priorities for the preservation of ecological and social functions of the forested landsapes. Using a simple linear approach, we argue that their situation can be considered as acceptable, when the percentage of the yearly burned area in relation to the total forested area is much lower than 100/T (for practical purposes just lower than 10/T). This empirical rule was applied to the Greek forested landscapes. In the case of pine forests of Pinus halepensis and Pinus brutia, it was found that the condition implied by the rule was not satisfied and, therefore, a reduction of the yearly burned areas of these lowland conifer forests is necessary. However, as far as the other types of forests, as well as macchia and phrygana are concerned, the condition is satisfied.

The value of the trackway system within a lowland plantation forest for ground-active spiders

European forest management guidelines include conservation and enhancement of biodiversity. Within plantation forestry, trackways provide contiguous permanent open-habitat with potential to enhance biodiversity. We examined the ground-active spider assemblage in the trackway network of Thetford Forest, Eastern England, the largest lowland conifer forest in the UK, created by afforestation of heathland and farmland. Results are relevant to other forests in heath regions across Europe. We used pitfall trapping to sample the spider assemblage of trackways within thicket-aged stands (n = 17), mature stands (n = 13) and heathland reference sites (n = 9). A total of 9,314 individuals of 71 species were recorded. Spider assemblages of the trackway network were distinct from those of the heathland reference sites; however, trackways were found to support specialist species associated with grass-heath habitats, including nationally scarce species. Richness of grass-heath species was similar for trackways in thicket-aged forest and heathland reference sites, although the abundance of individuals was three times greater in the reference sites. Trackways in mature stands had lower grass-heath species richness and abundance than both thicket trackways and heath reference sites. Wide trackways within thicket stands contained greater richness and abundance of specialist xeric species than narrower trackways. However, fewer xeric individuals were found in trackways compared to heathland reference sites. Either inferior habitat quality in trackways or poor dispersal ability of specialist xeric species may largely restrict these to relict areas of heathland. Targeted widening of trackways to allow permanent unshaded habitat and creating early successional stages by mechanical disturbance regimes could improve trackway suitability for specialist species, helping to restore connectivity networks for grass-heath biodiversity.

American black bear predation of an adult white-tailed deer

American black bears (Ursus americanus) are opportunistic omnivores and can be proficient predators of neonate ungulates, but predation of adult ungulates is rare. In November 2009 we investigated a probable black bear predation of a radiocollared, adult (7.5 years old) female white-tailed deer (Odocoileus virginianus) in a densely vegetated, lowland conifer forest in the Upper Peninsula of Michigan, USA. The deer carcass was 80% buried with puncture wounds and lacerations on the back and hindquarters. The hide was everted, the intestines and stomach partially eaten, the mammary glands were punctured, and the skeleton remained articulated. All woody vegetation <5.0 cm diameter within 5 m of the carcass was trampled and contained bear and deer hair. We found no evidence of other carnivores. Based on the condition of the carcass, physical evidence at the site, and the similarity of this predation to reported black bear predations, we suggest this deer was attacked and killed by a black bear.

Effects of local and regional landscape characteristics on wildlife distribution across managed forests

Understanding the impacts of local and regional landscape characteristics on spatial distributions of wildlife species is vital for achieving ecological and economic sustainability of forested landscapes. This understanding is important because wildlife species such as white-tailed deer ( Odocoileus virginianus) have the potential to affect forest dynamics differently across space. Here, we quantify the effects of local and regional landscape characteristics on the spatial distribution of white-tailed deer, produce maps of estimated deer density using these quantified relationships, provide measures of uncertainty for these maps to aid interpretation, and show how this information can be used to guide co-management of deer and forests. Specifically, we use ordinary least squares and Bayesian regression methods to model the spatial distribution of white-tailed deer in northern hardwood stands during the winter in the managed hardwood-conifer forests of the central Upper Peninsula of Michigan, USA. Our results show that deer density is higher nearer lowland conifer stands and in areas where northern hardwood trees have small mean diameter-at-breast-height. Other factors related with deer density include mean northern hardwood basal area (negative relationship), proportion of lowland conifer forest cover (positive relationship), and mean daily snow depth (negative relationship). The modeling methods we present provide a means to identify locations in forest landscapes where wildlife and forest managers may most effectively co-ordinate their actions.

Local winter deer density: Effects of forest structure and snow in a managed forest landscape

Abstract Background/Questions/Methods White-tailed deer (Odocoileus virginianus) are a ‘keystone herbivore’ with the potential to cause tree regeneration failure and greatly affect vegetation dynamics, stand structure and ecological function of forests across eastern North America. In northern mixed conifer-hardwood forests, local winter-time deer populations are dependent on habitat characterized by patterns of forest cover that provide shelter from snow and cold temperatures (lowland conifer stands) in close proximity to winter food (deciduous hardwood stands). Stand structure may also influence winter spatial deer distribution. Consequently, modification of forest cover patterns and stand structure by timber harvesting will affect local spatial deer distributions, with potential ecological and economic consequences. Here, we ask if forest cover pattern and stand structure, and their interactions with snow depth, can explain winter deer density in the managed forests of the central Upper Peninsula of Michigan, USA. For each local winter deer density estimate (from fecal pellet counts) we calculate stand-level characteristics for surrounding ‘landscapes of influence’ of radius 200 m. For these data, and modeled snow depth estimates, we use multivariate techniques to produce predictive models and to identify the most important factors driving local deer densities across our 400,000 ha study area. Results/Conclusions Distance to the nearest conifer stand consistently explains the most variance in univariate regression models. Deer densities are highest near lowland conifer stands in areas where mean hardwood tree diameter-at-breast-height is low. Multiple regression models including these factors explain 22% of variance in deer density and have up to a 65% chance of correctly ranking a site’s deer density (relative to other sites within our study area). We use model ensembles to produce maps of estimated deer density (and associated uncertainty) for a subset of our study area and show how managers might use these maps to aid co-management of deer and forest regeneration. Our results highlight the importance of local and regional factors (forest cover-type pattern, stand structure, climate) on winter white-tailed deer density in managed hardwood-conifer forests. Use of these results, and the simulation model being developed, will help identify management practices that can decrease deer impacts and ensure the ecological and economic sustainability of forests in which deer browse is proving problematic for tree regeneration.

Evaluation of Shifts in White‐Tailed Deer Winter Yards in the Adirondack Region of New York

ABSTRACT In the Adirondack region of northern New York, USA, severe weather and deep snow typically force white‐tailed deer (Odocoileus virginianus) to congregate in areas of dense coniferous cover and along watercourses at lower elevations. We examined 16 yards in the Adirondacks and explored the observation that deer have changed their movement behavior to incorporate residential communities within their wintering areas. We compared locations of deer herds in 2003 and 2004 to deer wintering areas mapped during the 1960s and 1970s. Deer were predominantly absent in 9 of 16 historical yards but were present in residential communities within the same drainage. Yarding areas to which deer shifted contained more residential, deciduous, and mixed cover than yards where no shift occurred, indicating that deer in residential areas were using conifer and mixed cover at a finer scale than deer in nonresidential areas. Smaller winter ranges and core areas of marked deer in a residential winter yard further imply greater concentration of resources available in these areas. Marked deer demonstrated flexibility in core winter range fidelity, a behavior that allows for more permanent shifts as habitat and food resources change or as new areas with appropriate resources are encountered. Our study suggests that low‐density residential areas in lowland conifer forests may provide an energetic advantage for deer during winter due to the assemblage of quality habitat interspersed with open areas and a variety of potential food sources in environments where movement is typically constrained by deep snow. Managers should consider the potential for changes in use of deer wintering areas prior to land conservation efforts and may need to adapt management strategies to reduce conflicts in communities occupied by deer during winter.

Movement and Habitat Use of Canada Lynx During Denning in Minnesota

Establishing whether conditions are suitable for reproduction would help determine if immigration is necessary for Canada lynx (Lynx canadensis) to persist at the southern edge of the species range. We located den sites and monitored reproduction of radiocollared lynx in Minnesota from 2004 to 2006. Movement rates of denning females measured with Global Positioning System collars were similar to movement rates of lynx elsewhere. Female lynx with kittens used different habitat types in predenning, denning, and postdenning periods. Landscape composition at the scale of the foraging radius around a den site contained more lowland conifer, upland conifer, and regenerating forest than did home ranges or the area used by radiocollared lynx in Minnesota, USA. We used the spatial distribution of cover-type composition around known den sites to predict and map potential denning habitat in northeastern Minnesota. Techniques for identifying the spatial distribution of suitable denning habitat provide a biological basis for management actions that could enhance recovery of Canada lynx populations in the southern part of the species range.

The soil seedbank of a lowland conifer forest: The impacts of clear-fell management and implications for heathland restoration

Understanding the composition and dynamics of soil seedbanks beneath mature conifer plantations is important for managing biodiversity in rotational forestry systems and in the restoration of former communities following the removal of tree crops. We examined the role of the buried seedbank in vegetation development after clear-felling of stands within coniferous plantation forest in eastern England. The buried seedbank of 29 mature stands planted in the early to mid 20th century on lowland heathland and marginal arable was determined by germination of seeds from soil cores (30 bulked cores per stand). Seedbank density was highly variable, with a mean of 3950 (S.D. ± 2400) seeds m −2. Ninety-eight species germinated, of which 37 were present in the surface vegetation of the mature stands; these 37 species had a higher density of seeds than the 61 species absent from the surface vegetation. Of those 61 species, 21 were recorded in the surface vegetation of recently replanted stands, suggesting that the seedbank may increase the plant diversity of replanted stands following clear-felling. The seedbank of mature stands was dominated by Urtica dioica and Holcus lanatus. Comparison of seeds in the top 20 cm of soil between four paired mature and replanted stands showed felling and cultivation prior to replanting had little effect on either the density of the buried seedbank or the vertical seed density profile. Twenty-nine of the species recorded in the buried seedbank of mature stands were characteristic of heathland assemblages of the region, but were present at low densities. Notably, a number of perennial grass species characteristic of heathland were absent, while Calluna vulgaris occurred in the seedbank of few stands and then at low density. The potential for grass-heath restoration following clear-felling of first rotation conifer stands investigated in this study is likely to be low.