11/3/2010. Jared T. Beaver. Deer are an economically and socially important game species;

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1 An evaluation of population estimators, seasonal forage availability, and nutritional carrying capacity for white-tailed deer in middle Tennessee Jared T. Beaver M.S. Candidate University of Tennessee, Knoxville Forestry, Wildlife and Fisheries Wednesday, November 3, :20 pm Room 160, Plant Biotech Building Deer are an economically and socially important game species; Increased in abundance and expanded their geographic range over the past century. Rooney 2001, Miller et al Deer are keystone herbivores: overabundant populations can have negative impact on the structure and species richness of an area; lead to a decrease in available nutrition for body maintenance and productivity during critical times of the year. Doesn t just affect deer! Casey and Hein 1983, Rossell Jr. et al

2 Density can be a misleading indicator of habitat quality; Should not assume a density-habitat quality relationship. US Army Corps of Engineers Van Horne 1983 Nutritional stress periods occur at different times of the year in different areas; Different vegetation types may be preferred at different times of the year; Density-habitat quality relationships can not be inferred from surveys across a single season or vegetation type. Castleberry et al Quantity vs. Quality Deer are forced to choose from what is available; Deer forage selectively based on nutritional demands associated with their current biological state: Energy vs. Protein Photo credit: Michael McCord Jones et al. 2009, Iglay et al

3 Energy or Protein? Previous research has evaluated NCC using CP summer forages tend to show greater variability in CP than DE deer believed to select forages by CP than DE Jones et al showed CP and DE were not correlated in summer analysis in intensively managed pine plantations in Mississippi. Jones et al. 2009, Mixon et al. 2009, Iglay et al Management for white-tailed deer has become increasingly popular among landowners; Overabundant deer herds can decimate understory; Lots of research evaluating deer browsing effects: limited one particular density level primarily in one specific vegetation type growing season Provide an assessment and cost-analysis for different density estimation techniques for white-tailed deer; Document the effects of deer browsing as related to deer density and seasonal forage availability and quality. 3

4 Determine forage availability and nutritional carrying capacity within: vegetation type, season, and areas of differing deer density; Evaluate two methods of determining nutritional carrying capacity as related to white-tailed deer; Provide management recommendations for habitat evaluation in vegetation types common across the Southeast. H 1 : Forage availability will be lower in later successional vegetation types, winter, and high deer density H 2 : Nutritional carrying capacity will be lower in later successional vegetation types, winter, and high deer density H 3 : Crude protein and digestible energy estimates will provide different nutritional carrying capacity estimates Arnold Air Force Base and AEDC Wildlife Management Area 15,816 hectares 113 km SE of Nashville in Coffee and Franklin county Eastern Highland Rim physiographic province 4

5 Deer Density effect: Security area: > 24 deer/km 2 WMA units 1 & 2: > 11 deer/km 2 Vegetation effect: Closed-canopy hardwoods Mature pine stand Middle-age pine stand Young closedcanopy pine stand Early succession Seasonal Effect 3942-ha Arnold Air Force Base 1490-ha Trees/Shrubs Vine/Brambles/Briers Forbs Vaccinium spp. Smilax spp. Phytolacca americana Nyssa sylvatica Rubus spp. Desmodium spp. Euonymus americanus Vitis spp. Ambrosia spp. Cornus florida Lonicera japonica Potentilla spp. Rhus spp. Rosa multiflora Galium spp. Acer rubrum Dioscorea villosa Viola spp. Parthenocissus Asteraceae spp. Quercus spp. quinquefolia (family) Ulmus spp. Ipomoea spp. Aralia spinosa Toxicodendron radicans Ligustrum vulgare * Harlow and Hooper 1972, Miller and Miller 1999 Five 100-m transects/vegetation type Five sample plots per transect 10-m 30-m 50-m 70-m 90-m 1 - m 2 - m 5

6 Forages will be collected by species all leaf biomass will be collected from woody species entire herbaceous plant excluding large stems Wet weights will be recorded Collect > 30 g known wet weight sample of each species within each vegetation class Dried in walk-in forced air- flow dryer (55 0 C) Weighed after drying Ground using 1-mm-mesh Sent to SURE-TECH TM Laboratories for nutritional analysis Wet-dry mass ratio for each forage species Dry weights will be extrapolated over total coverage for each vegetation type total available dry matter biomass (kg/ha) 6

7 NCC: deer-days/ha NCC based on crude protein nutritional constraint (Hobbs & Swift 1985): 6% CP (Holter et al. 1979, Jones et al. 2009) 14% CP (Verme and Ullrey 1984) 1.36 kg/deer/day (dry weight biomass) (Holter et al. 1979) NCC based on digestible energy nutritional constraint: 2.2 kcal DE/g DMI (Jones et al. 2009) 3.25 kcal DE/g DMI (Campbell et al. 2002) 159 kcal/kg 0.75 /day (dry weight biomass) (Hillickson and DeYoung 1997, McCall et al. 1997) Mixed-model ANOVA with repeated measures RBD with repeated measures across season Fixed effects: deer density, vegetation type My committee members: Drs. Craig Harper, Frank van Manen, Lisa Muller, Robert Kissell Jr., and John Waller Funding agencies: USFWS & DoD Rick McWhite, AAFB Natural Resource Manager Wes Winton, AEDC WMA manager Seth Basinger and Matt Goode 7

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