DAMA GAZELLE RADIO COLLAR STUDY Mungall, p. 1 Home range size proposal, March 2012

Transcription

1 DAMA GAZELLE RADIO COLLAR STUDY Mungall, p. 1 Project proposal from Dr. Elizabeth Cary Mungall To further a dama gazelle biology investigation via the Second Ark Foundation, Ingram, Texas Photos by Dr. Elizabeth Cary Mungall courtesy of Stevens Forest Ranch

2 DAMA GAZELLE RADIO COLLAR STUDY Mungall, p. 2 EXECUTIVE SUMMARY PROPOSAL: Dama Gazelle Radio Collar Study to Determined Home Range Size OBJECTIVE: To promote herd growth (for either ranch or reintroduction). TIME SPAN: 1 year (to cover all four seasons) plus 3 months for collar retrieval and data mapping. COST: $14,585 split between 2012 ($8,600) and 2013 ($5,985) and with multiple partners. BENEFITS: Determine seasonal spacing of dama gazelles. This will help estimate breeding patterns and ultimate population numbers that can be accommodated under various conditions. BACKGROUND: Given this insight into use patterns by dama gazelles, people working with this species can project more efficiently how breeding groups may assort within an area and the composition of the population for maximum breeding opportunities with minimum friction (harassment, fights, mortality) within the population. Radio collars are expected to work more effectively than the direct observation which has been tried. There may be two main reasons. 1. Dama gazelles are semi-desert animals and so may be adapted to wander over large areas in order to find adequate forage. 2. Dama gazelles, like their close relatives Grant s gazelles, may be adapted to using much larger areas even if localizing their activity. METHODOLOGY: 1. Meet with Steve Forest, landowner of the large rangeland study site with a breeding population of dama gazelles, to settle details of the study plan. 2. Get Forest s advice on capture locations. 3. Work with Forest and with Dr. Susan M. Cooper and her technicians from the Texas A&M AgriLife Research and Extension Center in Uvalde, Texas, to capture, radio collar, and monitor 5 adult males and 3 adult females for one year. 4. Use radio signals to monitor the radio collars and then to locate the auto drop-off collars after 1 year. 5. Cooper s technicians will then download the latitude and longitude data and map it for Dr. Mungall s interpretation. 6. Mungall will prepare report. Cooper and her team have successfully used similar procedures to collect similar information for native white-tailed deer. See figure 1 for diagrams of four of the possible outcomes. DELIVERABLES: Map of locations on CD showing grouping of fixes, summary of interpretation. CD for each major sponsor. For landowner, also a poster-size map of range sites included within the study area used. FUTURE APPLICABILITY: 1. Test for different density effects. 2. Test for proximity effects by using shorter location intervals for fewer months. 3. Use radio collars with digital cameras attached. CONTACT INFORMATION: Dr. Elizabeth Cary Mungall, 646 Shin Oak Way, Kerrville, TX 78028, emungall@gmail.com, (830)

3 DAMA GAZELLE RADIO COLLAR STUDY Mungall, p. 3 Two male territories each with its own female group. Two male territories, one wandering female group. Overlapping male home ranges, one wandering female group. One male territory with its own female group; bachelor group excluded. FIGURE 1: EXAMPLES OF POSSIBLE USE AREAS (SIMPLIFIED).

4 DAMA GAZELLE RADIO COLLAR STUDY Mungall, p. 4 STUDY PLAN Objective: To promote herd growth, whether for ranch propagation or for reintroduction, this radio collar study of dama gazelles on Texas rangeland will investigate seasonal spacing. With this information, managers can better estimate breeding patterns and ultimate population numbers that can be accommodated under various conditions. Background: This study is directed at a serious gap in a project that the Second Ark Foundation has been funding on the basic biology of dama gazelles (Gazella dama, alternatively called Nanger dama): how much space is enough space for normal dama gazelle behavior? The Second Ark Foundation and the Exotic Wildlife Association have been interested in the study of dama gazelles because this species has been particularly hard to establish as exotics, unlike other species such as scimitar-horned oryx (Oryx dammah) from similar native habitat and Indian blackbuck antelope (Antilope cervicapra) which is a relative of gazelles. Working in the Texas Hill Country where the raising of exotic hoofed stock is a major activity and where there has been much interest in establishing populations of this rare species, this investigation has been following the life histories of known individuals born during the project. However, Hill Country experience has been that mature males end up in lethal fights when allowed in the same pasture and a herd male will harass and kill maturing males if they are not withdrawn soon enough. Thus, the standard Hill Country model is to keep only single-herd groups. The proposed radio collaring study asks, how much space is enough space so that a self sustaining population can include multiple adult males? How big is a male s normal home range under unrestricted Texas conditions? Do these home ranges overlap and, if so, do males use the overlap zone at the same time or only at different times? Do males

5 DAMA GAZELLE RADIO COLLAR STUDY Mungall, p. 5 appear to be territorial? Do females stay with a particular male or do they range more widely? With habitat shrinking in the wild, these questions have relevance for conservation programs in native habitat as well as for safe-harbor breeding programs in the United States. Recent estimates are that there may be only 300 dama gazelles left in the wild, and that what is left of their core home in the Sahel on the semi-desert southern fringe of the Sahara may only have one or two populations with enough animals (about 20) to be self sustaining (Mallon 2012, J. Newby, pers. comm.). The dama gazelles in Texas are all realistic candidates for reintroduction as well as ideal safeguards against extinction in the wild. This is because it is known where all of the dama gazelles in Texas came from in Africa. All of this makes improved dama gazelle husbandry, and a project like what is proposed here, particularly important. Timing and cost justification: Ideally, the radio collars for this project will be placed on the animals before the middle of May. After May, it is likely to become too hot to capture animals until the summer heat abates in mid October. Spring rather than fall will also be best because the animals have had a wet winter to recover from the drought of last summer. By fall, the animals may just be coming out of another stress period. The proposed project is an exceptionally good deal. AgriLife Research and Extension Center in Uvalde is presently in between projects enough to be able to lend out eight radio collars with only a charge for battery packs and drop-off units: total for the eight complete collar units $3,520. By contrast, collars from a commercial distributor such as Advanced Telemetry Systems (ATS) would cost $20,000 for eight complete collars, more than a third again as much as the whole two-year budget in the present proposal (ATS 2011, J. Roth pers. comm.). Moreover, the Uvalde lab presently has enough room in their schedule to be able to track, download, and map the data for $3,090, whereas receiving the ATS data would cost $3, for the same number of fixes without including any mapping. If cost were comparable, then collars like the ATS units with satellite transmission of locations during the course of the project year would be attractive. With such a difference in cost, the increased effort to check periodically on the animals using an antenna and radio receiver to track them in the field is well justified. This is too good an opportunity to miss. A detailed budget is given at the end of the proposal. Materials and Methods: To minimize the effect of fencing limiting travel, a really large ranch has been recruited for this project. Steve Forest of Stevens Forest Ranch has generously agreed to allow his population of approximately 75 dama gazelles in 25,993 acres to be used for this study. Navigating such large distances to capture animals will be done by helicopter using a net gun. Radio collars are expected to work more effectively than the direct observation which has been tried with limited success for pastures larger than 60 acres. There may be two main reasons. First, dama gazelles are semi-desert animals and are known to have wandered over long distances in order to find forage (Estes 1992). Second, dama gazelles, like their close relatives Grant s gazelles (Gazella granti, alternatively called Nanger granti), may be adapted to using much larger areas even if localizing their

6 DAMA GAZELLE RADIO COLLAR STUDY Mungall, p. 6 activity. For example, Grant s gazelles have territories of 37 to 148 acres; in Africa, a single Grant s gazelle territory has been seen to overlap 10 Thomson s gazelle territories when both of these species are using the same habitat (Walther et al. 1983). At typically 2 to 12 acres, Thomson s gazelle territories are more like the 5 to 22 acre territories of blackbuck antelope in either Texas or their native India (Walther et al. 1983). Being large gazelles, the study subjects should easily be able to accommodate the radio collars. Generally, 3% of body weight is considered the upper limit for tagging devices. At a female body weight of about 90 lbs. (41 kg,), 3% equals 2.7 lbs. (3% equals 1.2 kg) and a male body weight of about 124 lbs. (56 kg), 3% equals 3.7 lbs. (3% equals 1.7 kg) all adult should be able to carry the 0.7 to 0.9 lb. (0.3 kg to 0.4 kg) collars. Dama gazelle neck circumference of 12 in. female to 15 in. male as measured during the Second Ark Foundation work should fall within the tolerances of the Uvalde doe and buck collars. Collars have about 1 in. band adjustment available, and padding will be added to increase comfort as well as fit. Colored tape around the collars will aid visual identification for radio tracking animals in the field. Monthly field tracking with antenna and radio receiver in the field during the year-long project will assure the investigators that the collars are functioning properly, that the collars are still on the animals, and that the animals are alive. Additionally, this interim tracking should give the experimenters an idea of what area the animals are using and so make it easier to locate the collars once they drop off. Drop-off time will be programmed for 53 weeks instead of 52 in order to allow tracking time at the end of the project for retrieving the collars. After the collars are retrieved, the location data stored in the collars will be downloaded at the Uvalde lab and mapped. Each day should be represented by 8 fixes, 1 every 3 hours. Looking at this by season as well as for the whole year and by habitat type as well as by relative spacing among animals will add important detail to the results. Four of the possible outcomes are diagrammed in figure 1.

7 DAMA GAZELLE RADIO COLLAR STUDY Mungall, p. 7 MAJOR PERSONNEL Steve Forest, owner and operator of Stevens Forest Ranch, started out raising exotic hoofed stock in Bandera, Texas. Later, he moved the bulk of his activity to a much larger property near Dryden, Texas, which is west of Del Rio. Here, he keeps breeding groups of numerous animals, including many African species, as well as natives such as white-tailed deer, mule deer, javelina, and turkeys. Forest has been a director of the Exotic Wildlife Association, has worked with state biologists on habitat enhancement, and has made himself proficient with helicopter capture. Since 1975, net gun operation has become one of his special talents, a great asset for the present project. Dr. Susan M. Cooper, now an associate professor of wildlife ecology with Texas A&M University, is a senior staff member at Texas A&M s AgriLife Research and Extension Center in Uvalde, Texas. She was recruited from southern Africa for the Uvalde study team after working on African species such as greater kudu and impala in native habitat. In Texas, Cooper works with both students and agency personnel to develop and implement rangeland investigations of value to Texas landowners. Recent involvement has included Cooper and her team radio collaring native white-tailed deer for monitoring on rangeland. The present project will be drawing on this expertise. Dr. Elizabeth Cary Mungall, principal investigator for this project, is an adjunct professor of biology with Texas Woman s University. Mungall started studying exotic hoofed stock on a blackbuck antelope territoriality investigation supervised by Dr. Fritz R. Walther, a world renowned gazelle specialist, through Texas A&M University. Since then, she has worked on other exotic species and topics, summarizing much of her findings in books, such as the Exotic Animal Field Guide from Texas A&M University Press, as well as in shorter magazine articles and scientific papers (see list of selected references). In this way, she seeks to make results available to both popular and academic audiences. Mungall has been conducting research into the basic biology of the

8 DAMA GAZELLE RADIO COLLAR STUDY Mungall, p. 8 dama gazelles on Texas rangeland since However, her particular interest in this species dates to zoo observations in the 1970 s which included individuals imported from native habitat in central Africa (Mungall 1980, Walther et al. 1983). SELECTED REFERENCES Publications, meeting poster displays, and film documentary already generated by the dama gazelle biology investigation: Mungall, E.C Ranch research significant for zoo success of dama gazelles. Proceedings of the 36 th National Conference of the American Association of Zoo Keepers, Inc., AAZK, Inc., Galveston, TX. Pp Herd behavior and population dynamics of the dama gazelle, poster presentation and abstract. Annual meeting of the American Zoo and Aquarium Association, Houston, TX Miracle milk results of the latest Second Ark Foundation research project. Exotic Wildlife, July-Aug. issue. P Variations on a theme. Exotic Wildlife, Nov.-Dec. issue. P. 26., K. Kyle, and S.A. Smith Management implications of social maturation among captive dama gazelles, abstract. Human-Wildlife Interactions, Texas Chapter of The Wildlife Society, Beaumont, TX. P. 60.,, and Mortality and remediation for exotic dama gazelles, abstract. How Green? The Complex World of Wind Power Development and Wildlife, Texas Chapter of The Wildlife Society, Lubbock, TX. Pp ,, and Dama gazelle research: a model for conservation advantages from exotics populations, poster presentation and abstract. Species Introductions and Re-Introductions Symposium 2010, Mississippi State University, Starkville, MS.,, and Drought, age, and competition effects on reproduction in dama gazelles, abstract. 47 th Annual Meeting of the Texas Chapter of The Wildlife Society, San Antonio, TX. P. 46. and C. Mungall Film documenting a dama gazelle s first steps, awarded first prize in video competition at the Texas Chapter of The Wildlife Society meeting in San Antonio, TX.

9 DAMA GAZELLE RADIO COLLAR STUDY Mungall, p. 9 Other dama gazelle material in publications by proposal s principal investigator: E.C. Mungall Courtship and mating behavior of the dama gazelle (Gazella dama Pallas 1766). Der Zoologische Garten. 50: Exotic Animal Field Guide: Nonnative Hoofed Mammals in the United States. Texas A&M University Press, College Station, TX. 286 pp. Walther, F.R.,, and G.A. Grau Gazelles and Their Relatives: A Study in Territorial Behavior. Noyes publications, Park Ridge, NJ. 239 pp. General references for the proposal text: ATS Advanced Telemetry Systems, advertising folder, Isanti, MN. 24 pp. Estes, R.D The Behavior Guide to African Mammals: Including Hoofed Mammals, Carnivores, Primates. The University of California Press, Berkeley, CA. 611 pp. Mallon, D Antelope Specialist Group and international antelope conservation, Connect, March. Pp

10 DAMA GAZELLE RADIO COLLAR STUDY Mungall, p. 10 BUDGET DAMA GAZELLE RADIO COLLAR STUDY FOR HOME RANGE SIZES AND OVERLAP FOR 2012 FOR 2013 Stevens Forest Ranch study site - Steve Forest owner To Steve Forest for facilitating project $ Helicopter, net gun, gunner: $350/hr. for 4 hr. $1, Ground crew for capture: $200/man for 2 men $ Selenium shots and minor medication for animals as needed $ Uvalde AgriLife Research team - Dr. Susan M. Cooper team leader To Dr. Susan M. Cooper, Texas A&M System, for overseeing Uvalde team $1, Radio collars (5 buck size in., 3 doe collars in.) loan loan Collar battery packs: made at Uvalde lab for $140/collar for 7 collars $1, Drop-off units: about 6 weeks to order, $300/collar for 7 collars $2, Mileage for state vehicle: 410 mi. round trip x $0.50/mi $1, $1, start, monthly, and end visits to place, track, and retrieve collars Use of software and hardware for downloading data from retrieved collars: Uvalde lab donated 14 days technician salary for collar placement, tracking, retrieval $1, $1, data processing and mapping Map showing final results for home ranges: $300 value donated Use of radio antenna and receiver: Uvalde lab loan loan To Dr. Elizabeth Cary Mungall, principal investigator, for coordinating $1, project working through Second Ark Foundation, Ingram, Texas Product: map of locations on CD to ranch and to each major sponsor TOTAL REQUESTED FOR PROJECT $14, no charge $8, $5, FOR 2012 FOR 2013