Scott E. Hygnstrom

Effects of agricultural activities and hunting on home ranges of female white-tailed deer

Insight into the effects of agricultural activities and hunting on deer could be used to facilitate management. We examined home range characteristics of female white-tailed deer (Odocoileus virginianus) relative to corn development, corn harvest, and hunting seasons from 1991 to 1993. Among 30 radiomarked does, 53% (n = 16) remained residents of DeSoto National Wildlife Refuge (DNWR) throughout the study; 47% (n = 14) were transients. Among the transients, 30% (n = 9) permanently emigrated from DNWR and 17% (n = 5) migrated annually. Dispersal occured in April and May. Annual home ranges of resident does averaged 170 ha (CI = 38, n = 14). Home range centers shifted an average of 174 m (CI = 74, n = 14) closer to cornfields when corn was in the tasseling-silking stage of development. After corn harvest, home range centers shifted 157 m (CI = 63, n = 12) away from crop fields and into areas of permanent cover. Home range sizes increased 32% (9-64% CI) after corn harvest because does were forced to find and use other sources of cover and food. Resident does that caused local crop damage during the growing season were available for hunter harvest in the same areas where they caused damage. Migrators appeared especially vulnerable because they were exposed to state firearm and archery seasons and the DNWR 3-day muzzleloader hunt. Of all tagged deer, 20% of transients (3 of 15) were harvested legally, whereas 40% of residents (8 of 20) were harvested. Harvest or removal to reduce crop damage around large areas of permanent cover should be conducted in early to mid-fall, which can reduce deer densities in the immediate area but not impose additional hunting pressure on migratory deer.

Fences and Deer-Damage Management: A Review of Designs and Efficacy

Abstract White-tailed deer (Odocoileus virginianus) may cause more damage than any other species of wildlife. These damages include crop loss, automobile and aviation collisions, disease transmission, environmental degradation, and destruction of ornamental plantings. One practical method of controlling deer damage is the use of exclusionary fences. The relatively high cost of labor and materials required to build effective fences has limited most applications to the protection of orchards, vegetable farms, other high-value resources, and mitigation of human health and safety risks. Improvements in fence technology resulting in less expensive, yet effective fences have expanded the use of fences to manage damage caused by deer. Fences typically installed to manage white-tailed deer damage include wire or plastic mesh, electrified high-tensile steel wire, and electrified polytape or polyrope fence. We reviewed the scientific literature on fencing to determine which fence designs would be the most effective for excluding deer in a variety of situations.

Use of Frightening Devices in Wildlife Damage Management

Wildlife is often responsible for causing extensive damage to personal property, human health and safety concerns, and other nuisance problems because of their feeding, roosting, breeding, and loafing habits. Frightening devices are tools used in integrated wildlife damage management to reduce the impacts of animals, but the effectiveness of such devices is often variable. An animals visual and auditory capabilities affect how the animal will respond to a stimulus. Frightening devices include pyrotechnics, gas exploders, effigies, lights, lasers, reflective objects, guard animals, bioacoustics, and ultrasonic devices. We examined scientific literature on the use of frightening devices to reduce bird and mammal depredation and compiled results to determine the effectiveness of such devices. When used in an integrated system, frightening devices may be more effective than when used alone. We conclude that the total elimination of damage may be impossible, but frightening devices and/or combinations of devices are useful in reducing wildlife damage. Ultrasonic frightening devices are ineffective in repelling birds and mammals whereas other devices offer some protection. The timely use of a variety of frightening devices can be part of a cost-effective integrated system to reduce wildlife damage to tolerable levels.

Prevalence and Serovars of Salmonella in the Feces of Free-Ranging White-Tailed Deer (Odocoileus virginianus) in Nebraska

To determine the prevalence and serovars of Salmonella in free-ranging deer, we cultured feces from white-tailed deer (Odocoileus virginianus) harvested by hunters during a regular firearm season in southeastern Nebraska (USA). We recovered Salmonella from 5 (1%; 95% confidence interval: 0.37–2.20%) of 500 samples and identified four different Salmonella enterica serovars [Litch-field (1), Dessau (1), Infantis (2), and Enteritidis (1)]. Although the prevalence of Salmonella in free-ranging deer appears to be low, the serovars recovered are known to be pathogenic to humans and animals.

Management of damage by elk (Cervus elaphus) in North America: a review

Abundant populations of elk (Cervus elaphus) are cherished game in many regions of the world and also cause considerablehuman-wildlifeconflictsthroughdepredationonagricultureandspecialitycrops,lackofregenerationtonative ecosystems,collisionswithvehiclesandtransmissionofdiseasebetweenfree-rangingandfarmedhoofstock.Managementof elk varies, depending on current and historical agency objectives, configuration of the landscapes elk occupy, public perception, population density and behaviour of elk. Selection of the method to manage elk often requires knowledge of timing of impacts, duration relief from elk damage is desired, cost-effectiveness of management activities, tolerance of impacts, public perception of management strategies and motivation or habituation of elk to determine the likelihood of success for a proposed management action. We reviewed methods that are available to control abundant populations of elkthatincludelethal(e.g.hunting,sharpshooting)andnon-lethal(e.g.fertilitycontrol,frightening)options.Wepromotean integrated approach that incorporates the timely use of a variety of cost-effective methods to reduce impacts to tolerable levels.Lethaloptionsthatincluderegulatedhunting,sharpshootingandaerialgunningvarybylikelihoodofsuccess,duration neededforpopulationreduction,costtoimplementreductionandpublicperceptions.Severalnon-lethaloptionsareavailable to affect population dynamics directly (e.g. fertility control, translocation), protect resources from damage (e.g. fences, repellents) or influence space use of elk on a regular basis (e.g. harassment, frightening, herding dogs, humans). Public perceptionshouldbeconsideredbyagenciesthatarelookingforfeasiblemethodstocontrolpopulationsofelk.Disturbance to residents or visitors of public property may influence methods of management employed. Future research should explore thedurationofharassmentneededtoavertelkfromsensitiveareasandcoststoimplementsuchprograms.Severalmethodsin ourreviewwereimplementedondeerandadditionalresearchonelkandothercervidsinconflictwithhumaninterestswould provide a much needed component to our understanding of management methods available for ungulate species.

Evaluation of a deer-activated bio-acoustic frightening device for reducing deer damage in cornfields

Abstract Deer (Odocoileus spp.) can cause substantial damage to agricultural crops, resulting in economic losses for producers. We developed a deer-activated bio-acoustic frightening device to reduce white-tailed deer (O. virginianus) damage in agricultural fields. The device consisted of an infrared detection system that activated an audio component which broadcast recorded distress and alarm calls of deer. We tested the device against unprotected controls in cornfields during the silking–tasseling stage of growth in July 2001. The device was not effective in reducing damage: track-count indices (F1,4=0.02, P=0.892), corn yield (F1,9=1.27, P=0.289), and estimated damage levels (F1,10=0.87, P=0.374) did not differ between experimental and control fields. The size (F2,26=1.00, P=0.380), location (F2,25 =0.39, P =0.684), and percent overlap (F2,25 =0.20, P =0.818) of use-areas of radiomarked female deer did not differ between during- and after-treatment periods. We concluded that the deer-activated bio-acoustic device was not effective in protecting cornfields in this study; however, the device may be more effective in small areas such as gardens or for high-value crops that do not grow tall enough to offer protective cover.

Green and Blue Lasers are Ineffective for Dispersing Deer at Night

Abstract Over-abundant populations of white-tailed deer (Odocoileus virginianus) create agricultural and human health and safety issues. The increased economic damage associated with locally overabundant deer populations accentuates the need for efficient techniques to mitigate the losses. Although red lasers can be an efficient tool for reducing damage caused by birds, they are not effective for deer because deer cannot detect wavelengths in the red portion of the spectrum. No research has been conducted to determine if lasers of lower wavelengths could function as frightening devices for deer. We evaluated a green laser (534 nm, 120 mW) and 2 models of blue lasers (473 nm, 5 mW and 15 mW) to determine their efficacy in dispersing deer at night. Deer were no more likely to flee during a green or blue laser encounter than during control encounters. The green and blue lasers we tested did not frighten deer.

An Integrated Vehicle‐Mounted Telemetry System for VHF Telemetry Applications

Abstract We designed and developed a vehicle-mounted very high frequency–based telemetry system that integrated an on-board antenna, receiver, electronic compass, Global Positioning System, computer, and Geographic Information System. The system allows users to accurately and quickly obtain fixes, estimate and confirm locations of radiomarked animals, and immediately record data into an electronic spreadsheet or database. The total cost of materials to build the system was

Evaluation of Fences for Containing Feral Swine under Simulated Depopulation Conditions

7,349 (United States currency). Mean error angle of 2.63 ± 12.1° (SD; range = −33.7–42.2°) and mean location error distance of 128 ± 91.3 m (SD; range = 0–408 m) suggested precision and accuracy of our system were comparable to other reported systems. Mean time to record 5 bearings/test transmitter was 6.28 ± 0.24 minutes (SE), which is the most efficient system reported to locate animals in the field. Vehicle-mounted telemetry systems like ours provide additional value to studies that involve tracking highly mobile species because investigators need not take bearings from established receiving stations and because investigators can immediately recognize bounced signals and take additional bearings and optimize accuracy of location estimates.

Propane exploders and Electronic Guards were ineffective at reducing deer damage in cornfields

ABSTRACT Populations of feral swine (Sus scrofa) are estimated to include >2 million animals in the state of Texas, USA, alone. Feral swine damage to property, crops, and livestock exceeds