Ecology of White-Tailed Deer in South Dakota: Growth, Survival, and Winter Nutrition

Author

Lowell E. Schmitz

Document Type

Dissertation - University Access Only

Award Date

2006

Degree Name

Doctor of Philosophy (PhD)

Department / School

Wildlife and Fisheries Science

First Advisor

Jonathan A. Jenks

Keywords

white-tailed deer, winter, survival, population, growth, nutrition

Abstract

Few studies of the ecology of white-tailed deer (Odocoileus virginianus) have been conducted in South Dakota. Despite one subspecies of white-tailed deer (O. v. dakotensis) that inhabits the state, much variation occurs in growth and survival of the species. Furthermore, little is known about winter nutritional requirements of white-tailed deer during severe winters in South Dakota. The objectives of this study were: 1) To model antler and morphological characteristics of captive white-tailed deer while investigating a maternal effect, which potentially influences growth of white-tailed deer from the Black Hills of South Dakota; 2) To determine mortality and habitat use of white-tailed deer fawns in the southern Black Hills, South Dakota; and 3) To evaluate pelleted soy hulls as a lure forage for minimizing winter depredation by deer in South Dakota. Antler and morphological characteristics from 3 cohorts of captive South Dakota white-tailed deer were documented from spring 1997 through fall 2005. Deer were maintained at the Wildlife and Fisheries Research Facility at South Dakota State University. Sixty-one fawns were born during this study and averaged 3.6 kg at birth. Daily growth rates of fawns (pre-weaning) averaged 0.16 kg. At sixteen months-of-age deer weighed an average of 66.0 kg. Yearling females averaged 61.1 kg and yearling males averaged 70.0 kg. Males reached peak body mass at 78 months-of-age and averaged 112.2 kg. Mean peak body mass of first generation, east river (ER1) males was 36.9 kg heavier than first generation, Black Hills (BH1) males. Predictive equations for total body mass were (kg) = -232.530 + 0.565*neck circumference (cm) + 1.137*chest circumference (cm) + 5.620*nose-to-eye length (cm) + 0.436*total body length (cm) for males and -98.513 + 2.516*total body length (cm) for females. Peak antler development occurred at 78 months-of-age for most males and averaged 142 1/8 non-typical Boone and Crocket score. Gross non-typical scores differed (P = 0.020) between cohorts. It is likely that deer from the Black Hills are affected by a negative maternal effect. Second generation males have acquired 50% of the difference between first generation males in terms of body weight and 43% of the difference in antler scores. Seventy-eight fawn white-tailed deer were captured and fitted with motion sensing radio collars from 1999 – 2002. Fawns were captured through ground searches using doe behavior as an indicator of recent parturition. Total annual mortality was 65% with 59% of mortality occurring summer-fall (1 June through 31 October) and 8% winter-spring (1 November through 31 May). Of the 47 mortalities that occurred during study duration, predation caused 65%, illegal harvest accounted for 4%, and 31% were due to unknown causes. Months when mortalities did not occur were in April and May. Fifty percent of the summer mortality was male fawns and 50% of the winter mortality was male fawns. The null hypothesis that mortality is independent of sex was tested and failed to be rejected with 50% mortality for male fawns and 50% mortality for female fawns occurring for this study. Habitat preference for diurnal bedsites was evaluated for the first 120 days of a fawn’s life; 171 diurnal bed sites were evaluated. Ponderosa pine (Pinus ponderosa) and quaking aspen (Populus tremuloides) were the predominant tree species present. Overstory canopy cover at bed sites was less than 34%. Litter averaged 22.2% (+ 1.07) of understory cover at fawn bed sites, with slash averaging 9.1% (+ 0.52), grasses 38.4% (+ 1.19), and the presence of 14 species of shrubs. Based on results of diet trials, pelleted soy hulls were successful in maintaining captive deer and thus, were used in field trials. During winter 2000 – 2001, three farm sites that had a history of deer depredation were chosen to evaluate the effectiveness of using pelleted soy hulls as a lure forage to minimize depredation by deer. Short stopping deer by placing a preferred forage between deer and stored hay/grain was a technique employed by the South Dakota Department of Game, Fish and Parks employees during the winters of 1993-94 and 1996-97. Feeding at the three sites varied from 51 – 74 days. Estimate of deer numbers visiting feeding sites was 105 animals. Estimates were obtained from visual observations, photos obtained from motion sensing cameras placed at feeding sites, and landowner estimates. Feeds were weighed daily to determine intake. Based on feed consumption and estimates of deer numbers, approximately 0.68 kg/deer/day of feed was consumed.

Library of Congress Subject Headings

White-tailed deer -- Ecology -- South Dakota
White-tailed deer -- South Dakota -- Growth
White-tailed deer -- Wintering -- South Dakota
White-tailed deer -- Nutrition -- South Dakota

Format

application/pdf

Number of Pages

191

Publisher

South Dakota State University

Rights

Copyright © 2006 Lowell E. Schmitz. All rights reserved.

Recommended Citation

Schmitz, Lowell E., "Ecology of White-Tailed Deer in South Dakota: Growth, Survival, and Winter Nutrition" (2006). Electronic Theses and Dissertations. 392.
https://openprairie.sdstate.edu/etd/392