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Item Ecology of sympatric deer species in west-central Texas: methodology, reproductive biology, and mortality and antipredator strategies of adult females and fawns(Texas Tech University, 2007-12) Haskell, Shawn P.; Ballard, Warren B.; Wallace, Mark C.; Krausman, Paul; Bradley, Robert D.; McIntyre, Nancy E.Between the mid-1800s and -1900s mule deer (Odocoileus hemionus) declined to relict populations in west Texas. This event coincided with the advent of barbed-wire fencing and dug wells providing water by windmills, which brought an end to free-ranging livestock. Also coincident was rangeland conversion from grassland-savannah to more brush dominated habitats due to overgrazing and fire suppression. These conditions favored white-tailed deer (O. virginianus) that expanded their range westward with the brush into areas that were previously inhabited by mule deer only. Most local biologists would cite the west-Texas decline of mule deer as the result of unfavorable changes in rangeland habitats, which facilitated competitive exclusion by white-tailed deer. Others have speculated about effects of fragmentation and hybridization, although genetic introgression between deer species appears uncommon despite hybridization in sympatric contact zones. However, these conditions still exist in west Texas, and mule deer are making their comeback into their previous range that was only occupied by white-tailed deer 30 years ago. The question remains: why did mule deer disappear 100 years ago? We think we have the answer: diseases associated with livestock. To reach that overarching conclusion (as a hypothesis), we first: 1) refined our field methods, 2) studied reproductive biology, and 3) examined causes of death for adult females and fawns of both species in a contact zone in northwest Crockett County, Texas, an area that was inhabited only by mule deer 100 years ago and only by white-tailed deer 30 years ago. They are now of similar abundance. We also made a discovery regarding maternal antipredator strategies that seems interesting for both ecology and management. I will not expound here on detailed results, as each chapter has its own abstract of more appropriate form. Because we relied on deer location estimates by radiotelemetry to test hypotheses, I conducted a beacon study to determine errors and generate a predictive regression model. This model allowed me to assess whether or not objectives could be met given our field methods. I also created a common-sense approach to location estimation that incorporated subjective weighting by relative confidence in a signal received. I compared this approach to the commonly used maximum likelihood estimator. Other researchers may find my MATLAB files useful for beacon studies and location estimation by radiotelemetry triangulation (see http://www.rw.ttu.edu/haskell/ ). To interpret results from wildlife studies it is useful to know population densities. We used mark-resight and deer location data to generate a theoretically unbiased deer density estimate at our site in 2005 (approx. 30 deer/km2). We took advantage of this estimate to provide Texas Parks and Wildlife Department (TPWD) with the first scientifically valid field assessment of their deer survey methods from roads. As predicted, because of habituation behavior within (and perhaps beyond) the effective survey strip width, deer seemed to be clustered near roads as semi-permeable barriers to movement, although a displacement effect of approximately 30 m was also evident. We provided TPWD with recommendations to calibrate their non-random survey design to more defensible methods. Field methods for fawn studies have been continuously refined. Most prior studies suffered from potential positive survival biases because fawns were not captured as true neonates and survival rates may be lowest soon after birth. In fact, 9% of the fawns we captured died within 25 m of birth-sites; most of these were not handled prior to death. We agree with others that risk of marking-induced abandonment is low if females are allowed at least 3 hours postpartum to clean and nurse their young. We used vaginal implant transmitters (VITs) to locate birth-sites. We experimented with VIT design to determine variable efficacy. Despite previous behavioral observations from captive deer, we found that antennas protruding too far externally from the vulva were more likely to be prematurely expelled, presumably because deer pulled them out with their teeth. Also we found that previous models estimating ages of captive fawns by hoof growth predicted ages that were about 1.5 weeks too young for our free-ranging fawns. Thus, researchers should take considerable caution when applying models from captive deer to free-ranging populations. We found that white-tailed deer moved neonates farther faster from birth-sties than did mule deer females. We hypothesized that this observed phenomenon was due to differences in maternal antipredator strategies, to be discussed more later. I examined factors affecting birth dates of these sympatric species at 3 hierarchal levels. At the population level, white-tailed deer birthed 1 month earlier than mule deer, and both species birthed later when rain was reduced during the pre-rut and rut periods. We suggest that the different birthing (and presumably breeding) periods for these sympatric species was not the result of selective pressure against hybridization, but instead was the result of some degree of phylogenetic constraint from parent populations. That is, the white-tailed deer expanded from central Texas where birthing is in mid-June, whereas the mule deer (O. h. eremicus) originated from southwestern deserts where birthing is synchronized with convective rain storms later in summer. At the individual level, older and heavier females birthed earlier. Reproductive success from the previous year may have greater effect on timing of breeding and birthing at other sites than at our study site because females seemed to invest relatively little energy in rearing fawns at our site. Also, deer birthed later on the more overgrazed ranches, suggesting an inter-generational effect after other factors were accounted for in multiple regression. This deer herd likely exists near a K-carrying capacity that responds positively to rain. As predicted, white-tailed adult females survived better during a period of greater rain than during drought. Unexpectedly, mule deer females that had nearly 100% survival during drought had reduced survival 2 years after the substantial rains of 2004. We hypothesize that the rains of 2004 directly and indirectly created an environment more favorable for disease transmission. Reproductive rates were high for both species, but were reduced in 2006 following reduced rain in the pre-rut and rut period of 2005, although mule deer females may have been stressed for the reason previously cited. Hemorrhagic diseases were chronically endemic in both species, but white-tailed deer are thought to have previously obtained enzootic stability in Texas. Overall, mule deer fawns succumbed more to sickness and starvation, and white-tailed fawns were killed more by bobcats (Lynx rufus). Even in 2004, one of the wettest summers in west Texas history, sickness-starvation was the biggest killer of mule deer fawns. Apparent diseases were numerous, and diseases associated with domestic sheep may have been more pathogenic than those associated with cattle. Mule deer kept fawns nearby and close together to protect them from seemingly overabundant small predators (e.g., bobcats and foxes), in the absence of larger predators such as coyotes (Canis latrans). In contrast, white-tailed females separated fawns and were generally removed from them during the fawn hider phase, 3 weeks postpartum. Given the long evolutionary history of white-tailed deer with many large predators, this loose cohesion antipredator strategy may be adaptive in the presence of large predators, but was maladaptive in their absence because extirpation of large predators can release populations of smaller predators that could be defended against. While bobcats tended to kill healthy fawns, bobcat predation may be to some degree compensatory, as the only appreciable top-down limiting factor on this deer herd, if the long-term effect is to alleviate negative density-dependent consequences of life near K-carrying capacity. Data from adult female weights and survival and fawn survival, thymus glands, weight gain, new hoof growth, birth dates, and weaning dates indicated that this deer population was chronically stressed near a carrying capacity that fluctuated with rain, and that females invested relatively energy in rearing fawns. We suggest that it was pathogens introduced by livestock ranchers that were responsible for the historic decline of a naïve mule deer herd in west Texas. Mule deer appear to have developed some immunity and may eventually achieve enzootic stability similar to white-tailed deer. Human use of these private lands and the unhealthy deer herd has been consistent for decades and likely will remain so. Responsible deer management is impossible where human land-use practices affect ecology and demographics across fence-lines and top-down limitation is negligible. We recommend research into alternative economic means and public ecological education of youth and adults as the management action with greatest potential for desirable results.Item Evaluating an Extension program: the Texas 4-H Wildlife Habitat Evaluation Program(Texas A&M University, 2006-10-30) Feldpausch, Andrea MarieIn times of heightened environmental consciousness, conservation education programming has proven useful for providing information and promoting natural resource conservation and stewardship. In a study of the 2005 Texas 4-H Wildlife Habitat Evaluation Program (WHEP), a contest teaching youth about the fundamentals of wildlife science and management, I sought to determine if WHEP was successfully reaching its primary goal: promoting conservation by increasing knowledge and skills of youth in the wildlife field. Through a series of facilitator-led interviews with WHEP participants (n = 35) and a combination of internet and on-site surveys (consisting of 35 current participants, 22 control youth, 19 past participants, 25 parents, and 7 coaches obtained from program registration lists), I explored the influence of program participation on wildlife management knowledge, social and leadership skills, attitudes, and understanding of stewardship. I found that WHEP had a significant impact on knowledge of wildlife management techniques and ecological concepts. The program had little influence on attitudes because most youth had positive perceptions of natural resources management prior to program involvement. I also found that past participants of WHEP claimed a significant increase in skills after program participation, but current participants could not determine their own progress. This suggested a longer period of time was needed to gauge self improvement. Parents and coaches claimed the program had a large impact on youth through instilling knowledge and values, but also improving their social, cognitive, and leadership competencies. Adults also discussed issues with participation, including a lack of program expansion and support. From these results, I determined that WHEP was achieving its program goals, but needs to address the issue of expansion because of its low level of operation compared to other 4-H programs in Texas. Suggestions for program growth include targeting youth groups and counties, cross promoting with other conservation programs, and continuing recruitment in currently participating counties.Item Relationships among landowner and land ownership characteristics and participation in conservation programs in central Texas(Texas A&M University, 2005-08-29) Sanders, Jennifer CearleyRecent land ownership trends in Texas have created concerns for natural resource agencies throughout the state (Wilkins et al. 2000, 2003; Steinbach 2001, American Farmland Trust 2003). An increase in the number of small properties has been associated with drastic changes in management emphasis in many areas and has led to concerns regarding landscape and ecosystem-level processes. Additionally, these apparent changes in management emphasis have subsequently led to concerns regarding the effectiveness of traditional natural resource conservation programs for all types of landowners. In this study, I sought to quantify differences in landowner characteristics, attitudes, and motivations in the Leon River Watershed using an informant directed interview process (Holstein and Gubrium 1995). I contacted and interviewed 60 landowners in the 4 central Texas counties contained within the Leon River Watershed. I found that landowners in my study could be classified into 1 of 3 categories that represented distinct goals, attitudes and motivations regarding land ownership andagriculture and wildlife management. Born to the Land, Ag. Business, and Re-born to the Land owners each display strong ideals regarding the proper context of land management, extremely distinctive ethical attitudes regarding their role as stewards of their land, and identifiable differences in their willingness to participate in various natural resource conservation programs. Natural resource agencies and organizations will now have the ability to profile landowners as to their likelihood of participation in various types of programs and conservation initiatives. The findings of this study could lead to dramatic changes in the way landowners are viewed and dealt with by many natural resource professionals.Item Wildlife rehabilitation centers: Survey of rehabilitators’ attitudes, motivations, and knowledge & study of animal admittance to the South Plains Wildlife Rehabilitation Center(2012-08) Mcgaughey, Kathleen; Perry, Gad; Wallace, Mark C.; Farmer, MichaelWildlife rehabilitation centers and wildlife rehabilitators rehabilitate and release injured, sick, displaced, and orphaned wildlife. To study the wildlife aspect of wildlife rehabilitation, mammal and herpetofauna admittance records for the South Plains Wildlife Rehabilitation Center (SPWRC) from the years of 1991-2010 were recorded and examined. These admittance data can be used to better manage similar human-wildlife interactions, offer solutions to common rehabilitation problems, and assist in successful release and survival of rehabilitated wildlife. To study the human aspect of wildlife rehabilitation, a survey was conducted of wildlife rehabilitators in Texas in order to study rehabilitators’ characteristics, knowledge and beliefs of some basic wildlife and rehabilitation issues, attitudes towards animals, reasons for rehabilitating, as well as how these things impact their desire and ability to properly educate the public about wildlife, specifically in urban areas.