WHITE-TAILED DEER. Scientific Name: Odocoileus virginianus Species Code: M-ODVI. Status: Yellow-listed

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1 WHITE-TAILED DEER Scientific Name: Odocoileus virginianus Species Code: M-ODVI Status: Yellow-listed Distribution Provincial Range White-tailed deer occur in two disjunct regions of B.C.: The Peace River region and the southeastern portion of the province, particularly the lower valleys of the Kootenay, Columbia, Kettle and Okanagan (Stevens and Lofts 1988). Elevational Range: Sea-Level to Alpine Provincial Context They are most common in the Southern Interior and Peace River areas of the province. White-tails can occur from low elevation valley bottoms in the winter to alpine meadows in the summer. The provincial population is estimated to be animals. Project Area: Ecoprovince: Southern Interior Mountains Ecoregions: Columbia Mountains and Highlands, Rocky Mountain Trench Ecosections: Eastern Purcell Mountains (EPM), East Kootenay Trench (EKT) Biogeoclimatic Zones: IDFdm2; ICHmk1; ICHmw1; MSdk; ESSFdk, ESSFdku; ESSFdkp; ESSFwm; ESSFwmu; ESSFwmp; AT Ecology and Key Habitat Requirements Food and habitat requirements vary across its range but typically white-tailed deer are found in open Douglas-fir forests, Douglas-fir - Ponderosa pine forests, trembling aspen forests, deciduous riparian forests, floodplain forests or early structural stages of these broad forest types. It feeds on a variety of grasses, forbs and shrubs that occur in these ecosystems (Demarchi 1986) (Ehlers, Bennett and Corbett 1998). Feeding and cover areas must be in close proximity to each other (Stevens and Lofts 1988). During the spring areas of early green-up are important for feeding. These areas occur on moderate warm aspect slopes at low elevations. During the summer season white-tailed deer are usually found to migrate to higher elevation forests and riparian areas. Higher elevation habitats such as subalpine parkland, alpine tundra, and alpine and subalpine wet meadows may receive summer usage by migrant white-tails but these areas are not capable of sustaining a population. The fall finds white-tailed deer in the same habitat areas as in the spring season. (Demarchi 1986) The winter season forces them from higher elevation habitats to low elevation areas with specific habitat characteristics to ensure their survival. Winter survival for white-tailed deer is dependent on old growth or mature Douglas-fir stands, Ponderosa pine parkland or bunchgrass steppe habitats. If snow accumulations exceed 50 cm then an area is generally avoided (Ehlers, Bennett and Corbett 1998). It was found that in the TFL 14 study, low elevation Douglas fir forests with moderate slopes and shallow snow packs were the most commonly used winter habitat (Ehlers, Bennett and Corbett 1998). Breeding occurs during late November and early December and fawns are born in late May or June after a gestation of approximately 210 days (Stevens and Lofts 1988) (Banfield 1981). Stevens and Lofts 1988 report that parturition sites are usually on gentle slopes with abundant cover such as dense shrubs or tall grass. Like white-tailed deer good fawning habitat is in close proximity to suitable foraging areas (Stevens and Lofts 1988).

2 Average home range for white-tailed deer varies widely between individuals, sexes, and habitat occupied. Bucks generally use larger areas than the does occupying an average winter range of 2.79km 2 in the East Kootenays (Stevens and Lofts 1988). Deep snow can impede movements, especially young animals and therefore winter ranges are smaller than summer ranges. Important habitat features for White-tailed deer are summarized in Table 1. Table 1. Important habitat features for different seasons and snowpack conditions for White-tailed deer. Season/ Snowpack Winter/moderate to deep snowpack Winter/shallow snowpack spring summer / fall Habitat Feature topographic features that reduce snowpack (i.e. slopes, southerly aspects) tall, large-crowned conifers with high average canopy closure arboreal lichens tall shrub understory small forest openings topographic features that reduce snowpack (e.g. slopes, southerly aspects) patches of cover with shrub understory topographic features that encourage early growth openings that encourage early growth of herbaceous forage security/thermal cover near forage habitat (i.e. within 200 m) closed canopy forest with shrubby understory for fawning abundant forage, especially herbs and shrubs patches of cover interspersed with food. Project Specific Habitats White-tailed deer have been observed on the North Bench planning cell of the TFL, on northeast aspects within immature forests, during the winter. It has be hypothesized that this is a result of their attraction to fresh Douglas-fir needles and arboreal lichens from recent logging activity coupled with predator avoidance. Habitat Use and Life Requisites The life requisites that will be rated for White-tailed deer are: feeding and security/thermal cover which are described in detail below. Feeding Habitat Feeding requirements for white-tailed deer are related to the availability of forage species and season. During the spring areas of early green-up are important for feeding. This occurs at low elevations on moderate to steep, south facing slopes. Important spring forage species include Poa spp., junegrass, bluebunch wheatgrass and big sagebrush. Summer habitat consists of areas with a suitable mix of young to old forest areas, with an adequate supply of forage and cover elements. White-tailed deer are easily adapted to human disturbance such as forestry practices and often prefer to feed in such opening if nearby cover is available (U.S. Forest Service 1998). Key summer forage species include, and arboreal lichens. Winter forces white-tailed deer from higher elevation areas to low elevation habitats with moderate, warm aspect slopes where the snowpack is lower. Forage quality and quantity are at their lowest value during the winter (Strategy Committee 1996). As the snowpack increases the accessibility to forage species declines. Good nutrition during the winter season is especially important. Douglas-fir foliage from large, old trees is the most common forage species in the winter season. Arboreal lichens, and are also eaten during the winter. Ehlers et al 1998 found that whitetailed deer will concentrate in areas of recent harvesting, where they feed on the Douglas-fir needles and lichen litter fall that are a result of logging. Table 2 illustrates important forage plants for whitetailed deer in each season. Table 2. Important forage plants for White-tailed deer. Winter forage Spring forage Summer forage

3 Trees and Shrubs Douglas-fir needles twigs and branches of: soopolallie Rosa spp. Douglas-fir needles foliage of: ceanothus foliage of: ceanothus leaves Herbs hay and alfalfa bluebunch wheatgrass needle grasses bluegrasses Arboreal Lichens bluebunch wheatgrass needle grasses bluegrasses asters golden-rod Security/Thermal Habitat Thermal habitat allows deer to expend less energy to maintaining body temperature, allowing allocation of conserved energy to growth and reproduction. Thermal habitat can vary daily, seasonally, with prevailing weather conditions, and age, size and nutritional condition of the animal. In general, nighttime thermal cover should trap long-wave radiation and maintain warmer air temperatures (occurring under a closed canopy above a deer s head or above 3 m), reduce wind at deer height (occurring in a forest stand or dense underbrush) and intercept precipitation (occurring under a closed canopy and large crown volume). In general, daytime thermal requirements are met by areas that gather heat (on or near rock bluffs, in clearcuts) or intercept excessive solar radiation (canopy closure). Winter, represents a critical season for deer species due to the associated energetic costs of maintaining body temperature and moving through snow,. Forest cover influences snow depth, density and surface hardness (Nyberg & Janz 1990), and deer typically expend most energy walking through crustless, dense, deep snow (i.e., sinking depths greater than 25 cm). Conditions that produce favourable snow conditions for deer include dense young-growth (>10 m tall) and old-growth forests (Nyberg & Janz 1990). Canopy closure (i.e., stands, taller than 10 m, with greater than 60% crown completeness) exerts the most influence on snow interception, and creates areas with snow conditions that don t limit deer movement (Bunnell et al. 1985). Douglas-fir forests with deep, wide crowns and high crown closures intercept a lot of snow and are therefore important for cover during the winter. Old growth Douglas-fir forests at low elevations, on south-facing slopes with moderate to high crown closure are the preferred winter habitats for White-tailed deer. Additionally north aspects also provide good snow interception in the winter, as they can support denser stands of higher crown closures and therefore, may be used during severe weather conditions (Strategy Committee 1996). Security habitat for white-tailed deer is essential for hiding from hunters and predators. As with whitetailed deer the most effective security cover hides 90% of the animal at a distance of 60 m or less, and security patches need to be 180 m or more in diameter. Generally mature - old growth forests with a dense shrub or patchy conifer understory will satisfy security cover requirements. In the growing season uneven aged stands of Douglas-fir forests provide good protection from wind and heat loss. Winter range is defined as those areas with 10 to 45 % slope, having a south and/or west aspect, and below 1500 m in shallow to moderate snowpack zones or below 1000 m in deep snowpack zones (U.S. Forest Service 1998). Seasons of Use Table 3 summarizes the life requisites required for each month of the year.

4 Table 3. Monthly Life Requisites for White-tailed deer. Life Requisite Month Season Feeding, Security/Thermal January Winter Feeding, Security/Thermal February Winter Feeding, Security/Thermal March Winter Feeding, Security/Thermal April Spring Feeding, Security/Thermal May Spring Feeding, Security/Thermal June Summer Feeding, Security/Thermal July Summer Feeding, Security/Thermal August Summer Feeding, Security/Thermal September Fall Feeding, Security/Thermal October Fall Feeding, Security/Thermal November Winter Feeding, Security/Thermal December Winter Habitat Use and Ecosystem Attributes Table 2 outlines how each life requisite relates to specific ecosystem attributes (e.g., site series/ecosystem unit, plant species, canopy closure, age structure, slope, aspect, terrain characteristics). Table 4. Terrestrial Ecosystem Mapping (TEM) Relationships for each Life Requisite for White-tailed deer. Life Requisite Feeding Habitat Security/Thermal Habitat TEM Attribute - site: site disturbance, elevation, slope, aspect, structural stage - soil/terrain: bedrock, terrain texture, flooding regime - vegetation: % cover by layer, species list by layer, cover for each species list for each layer - site: elevation, slope, aspect, structural stage - soil/terrain: terrain texture - vegetation: % cover by layer, crown closure - mensuration: tree species, dbh, height Ratings There is a detailed level of knowledge of the habitat requirements of White-tailed deer in British Columbia to warrant a 6-class rating scheme. Provincial Benchmark Winter Growing Ecosection: East Kootenay Trench East Kootenay Trench Biogeoclimatic Zone: IDFdm IDFdm Broad Ecosystem Unit: Interior Douglas-fir Forest Interior Douglas-fir Forest (successional stage 2-3) (successional stage 2-3) Ratings Assumptions 1. Because of the high metabolic needs of this species (5 lbs of forage / 100 lbs animal weight) (Banfield 1981) Habitats that lack abundant forage in the form of shrubby or herbaceous vegetation (< 5% total cover ) rate 6 for feeding 2. Forest cover is necessary for security and thermal needs, and therefore forests with abundant canopy closure, and dense understory shrub cover rate Structural stage 1-4 have minimal winter value (suitability 4) for food and shelter.

5 4. Young forests (structural stage 5) may provide security and thermal habitat (suitability 2) depending on forage availability, subzone and snowpack. 5. Low elevation mature forests (structural stage 6) provide good winter habitat (suitability 1) because of the arboreal lichen abundance and canopy closure. 6. Old forests (structural stage 7) provide the best food availability in winter. With the appropriate slope, aspect, and adjacency with uneven-aged stands, old forests are good White-tailed deer habitat (suitability 1). 7. Structural stage 2 and 3 that provide abundant forage will be rated moderately high (suitability 2) during the growing season, when adjacent to security habitat. 8. Riparian habitat should provide good habitat throughout the growing season and provided forage plants are available will rate suitability 2. Ratings Adjustment Considerations Final capability and suitability map products may incorporate 1) landscape heterogeneity and connectivity; 2) habitats adjacent to significant anthropogenic disturbance regimes (e.g. roads, settlements); 3) interspersion of different structural stages within the landscape. Literature Cited Banfield, A.W.F The Mammals of Canada. University of Toronto Press. Canada. Bunnell, FL., RS. McNay, and CC Shank Trees and snow: the deposition of snow on the ground. A review and quantitative synthesis. BC Min. Environ. and Min. For., Victoria, BC. IWIFR- 17. Ehlers, T. S. Bennett, P. Corbett TFL #14 Ungulate Winter Range Inventory: Year /97. unpublished report for Crestbrook Forest Industries Ltd. Parson, B.C. Nyberg, JB. & DW. Janz. (technical editors) Deer and elk habitats in coastal forests of southern British Columbia. BC Min.For., BC Min. Environ., Wildl. Hab.Can., Council of For. Indust. BC., Victoria, BC. Stevens, V. and S. Lofts Wildlife Habitat Handbooks for the Southern Interior Ecoprovince. Volume 1: Species Notes for Mammals. Wildlife Report No. R-15. Ministry of Environment, Wildlife Branch. Victoria, B.C. Stevens, V Wildlife Diversity in British Columbia: Distribution and Habitat Use in Biogeoclimatic Zones Draft Report. Wildlife Interpretations Subgroup. B.C. Ministry of Environment, Lands, and Parks. B.C. Ministry of Forests. Victoria B.C. United States Forest Service Odocoileus hemionus. Biological data and habitat requirements. Internet. _ AND_HABITAT_REQUIREMENTS. html Waterhouse, M., H. Armleder and R. Dawson Winter Food Habits of Mule Deer. Ministry of Forests, Cariboo Forest Region, Extension Note #10, 2pp.