Physical Sciences and Mathematics Commons^™

Response Of Captive Skunks To Microencapsulated Tetracycline, Brandon S. Schmit, Thomas M. Primus, Jerome C. Hurley, Dennis J. Kohler, Shawna F. Graves

United States Department of Agriculture Wildlife Services: Staff Publications

A captive striped skunk (Mephitis mephitis) study was conducted between February and June 2004 at the United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services National Wildlife Research Center, Fort Collins, Colorado, USA. The main objective was to determine the percentage of adult striped skunks that were marked after consuming placebo oral rabies vaccine (ORV) baits containing 100 mg of an experimental microencapsulated (coated microparticle) tetracycline hydrochloride biomarker. Biomarkers were identified in the canine teeth and mandibles of five of five skunks that consumed an ORV bait. A second objective was to determine if …

Evaluating Commercially Available Rodenticide Baits For Invasive Gambian Giant Pouched Rats (Cricetomys Gambianus), Gary W. Witmer, Nathan P. Snow, Patrick W. Burke

United States Department of Agriculture Wildlife Services: Staff Publications

Gambian giant pouched rats (Cricetomys gambianus) are native to Africa, but they are popular in the pet industry in the United States. They were reservoir hosts during a monkeypox outbreak in the Midwestern United States in 2003. A free-ranging population became established on Grassy Key in the Florida Keys, apparently because of a release by a pet breeder. These rodents could cause significant damage to agricultural crops should they reach the mainland. Research under controlled conditions was needed to identify effective rodenticides for Grassy Key or other cases where an invasion of Gambian rats might occur. We tested …

New Evidence Suggests Southern China As A Common Source Of Multiple Clusters Of Highly Pathogenic H5n1 Avian Influenza Virus, Bin Wu, Chengmin Wang, Guoying Dong, Yunhai Guo, Dale L. Nolte, Thomas Jude Deliberto, Jianguo Xu, Mingxing Duan, Hongxuan He

United States Department of Agriculture Wildlife Services: Staff Publications

Highly pathogenic H5N1 avian influenza is considered an avian disease, although there is some evidence of limited human-to-human transmission of the virus. A global effort is underway to control or eradicate the highly pathogenic H5N1 avian influenza virus in poultry and prevent human exposure, both of which may also reduce the risk of pandemic emergence. Hemagglutinin gene sequences from 215 human H5N1 influenza viruses were used to trace the source and dispersal pattern of human H5N1 influenza viruses on a global scale. A mutation network and phylogenetic analyses of the hemagglutinin gene show that human H5N1 influenza viruses can be …

General Flips And The Cd-Index, Daniel J. Wells

University of Kentucky Doctoral Dissertations

We generalize bistellar operations (often called flips) on simplicial manifolds to a notion of general flips on PL-spheres. We provide methods for computing the cd-index of these general flips, which is the change in the cd-index of any sphere to which the flip is applied. We provide formulas and relations among flips in certain classes, paying special attention to the classic case of bistellar flips. We also consider questions of "flip-connecticity", that is, we show that any two polytopes in certain classes can be connected via a sequence of flips in an appropriate class.

Single View Reconstruction For Human Face And Motion With Priors, Xianwang Wang

University of Kentucky Doctoral Dissertations

Single view reconstruction is fundamentally an under-constrained problem. We aim to develop new approaches to model human face and motion with model priors that restrict the space of possible solutions. First, we develop a novel approach to recover the 3D shape from a single view image under challenging conditions, such as large variations in illumination and pose. The problem is addressed by employing the techniques of non-linear manifold embedding and alignment. Specifically, the local image models for each patch of facial images and the local surface models for each patch of 3D shape are learned using a non-linear dimensionality reduction …

LP Bounded Point Evaluations For Polynomials And Uniform Rational Approximation, Erin Militzer

University of Kentucky Doctoral Dissertations

A connection is established between uniform rational approximation, and approximation in the mean by polynomials on compact nowhere dense subsets of the complex plane C. Peak points for R(X) and bounded point evaluations for H^p(X, dA), 1 ≤ p < ∞, play a fundamental role.

Development Of Novel Ahr Antagonists, Hyosung Lee

University of Kentucky Doctoral Dissertations

Aryl hydrocarbon receptor (AHR) is a sensor protein, activated by aromatic chemical species for transcriptionally regulating xenobiotic metabolizing enzymes. AHR is also known to be involved in a variety of pathogenesis such as cancer, diabetes mellitus, cirrhosis, asthma, etc. The AHR signaling induced by xenobiotics has been intensively studied whereas its physiological role in the absence of xenobiotics is poorly understood. Despite a number of ligands of AHR have been reported thus far, further applications are still hampered by the lack of specificity and/or the partially agonistic activity. Thus, a pure AHR antagonist is needed for deciphering the AHR cryptic …

Archaeological Evidence For Resilience Of Pacific Northwest Salmon Populations And The Socioecological System Over The Last ~7,500 Years, Sarah K. Campbell, Virginia L. Butler

Anthropology Faculty Publications and Presentations

Archaeological data on the long history of interaction between indigenous people and salmon have rarely been applied to conservation management. When joined with ethnohistoric records, archaeology provides an alternative conceptual view of the potential for sustainable harvests and can suggest possible social mechanisms for managing human behavior. Review of the ~7,500-year-long fish bone record from two subregions of the Pacific Northwest shows remarkable stability in salmon use. As major changes in the ecological and social system occurred over this lengthy period, persistence in the fishery is not due simply to a lack of perturbation, but rather indicates resilience in the …

Cold Weather And The Potential Range Of Invasive Burmese Pythons, Michael L. Avery, Richard M. Engeman, Kandy L. Keacher, John S. Humphrey, William E. Bruce, Tom C. Mathies, Richard E. Mauldin

United States Department of Agriculture Wildlife Services: Staff Publications

The Burmese python (Python molurus bivittatus) is established in Everglades National Park and neighboring areas in south Florida. Beyond its substantial ecological impacts to native fauna in south Florida, concerns have been raised as to its potential to occupy other parts of the USA, even as far north as Washington, DC. During a recent period of cold weather, seven of nine captive Burmese pythons held in outdoor pens at our facility in north-central Florida died, or would have died absent our intervention. This cold-induced mortality occurred despite the presence of refugia with heat sources. Our findings cast doubt …

Comparison Of Endocrine Response To Stress Between Captive-Raised And Wild-Caught Bighorn Sheep, Sarah Coburn, Mo Salman, Jack Rhyan, Thomas Keefe, Matthew Mccollum, Keith Aune, Terry Spraker, Lowell Miller

United States Department of Agriculture Wildlife Services: Staff Publications

Stress hormones in Rocky Mountain bighorn sheep (Ovis canadensis canadensis), produced in response to environmental changes, road development, or high population density, may impact their immune systems to a threshold level that predisposes them to periodic, large-scale mortality. We compared the stress response to a novel environmental situation and repeated handling between bighorn sheep born and raised in captivity (CR) and bighorn sheep born in the wild (WC) and brought into captivity. We measured plasma epinephrine, norepinephrine, cortisol, and fecal glucocorticoid metabolites (FGM). Three weeks after each group’s arrival we used a one-time drop-net event to elicit an …

Kill Rates And Predation Patterns Of Jaguars (Panthera Onca) In The Southern Pantanal, Brazil, Sandra M. C. Cavalcanti, Eric M. Gese

United States Department of Agriculture Wildlife Services: Staff Publications

Jaguars (Panthera onca) often prey on livestock, resulting in conflicts with humans. To date, kill rates and predation patterns by jaguars have not been well documented. We studied the foraging ecology of jaguars in an area with both livestock and native prey and documented kill rates, characteristics of prey killed, patterns of predation, and the influence of prey size on the duration at kill sites and the time interval between kills. Between October 2001 and April 2004 we monitored 10 jaguars equipped with global positioning system (GPS) collars. We collected 11,787 GPS locations and identified 1,105 clusters of …

Feral Swine Behavior Relative To Aerial Gunning In Southern Texas, Tyler A. Campbell, David Long, Bruce Leland

United States Department of Agriculture Wildlife Services: Staff Publications

Feral swine (Sus scrofa) impact resources through their destructive feeding behavior, competition with native wildlife, and impacts to domestic animal agriculture. We studied aerial gunning on feral swine to determine if aerial gunning altered home range and core area sizes, distances between home range centroids, and distances moved by surviving individuals. We collected data before, during, and after aerial gunning in southern Texas. Using Global Positioning System collars deployed on 25 adult feral swine at 2 study sites, we found home range and core area sizes did not differ before and after aerial gunning. However, feral swine moved …

The Effect Of Enclosure Type On The Behavior And Heart Rate Of Captive Coyotes, Stacey P. Brummer, Eric M. Gese, John A. Shivik

United States Department of Agriculture Wildlife Services: Staff Publications

The potential for captivity to elicit changes in animal behavior and physiology is well known. Recent research on captive populations has examined the effect of feeding protocols, enclosure types, and enrichment programs on indices of stress and displays of species-typical behaviors. We investigated the impact of enclosure type upon captive coyotes (Canis latrans) by examining differences in coyote behavior and heart rate, among 3.3m² kennels (K), 65.5m² small pens (S), and 1000m² large pens (L). Time budgets and repertoire of species-specific behaviors were compared among each enclosure type and to a sample of wild (W) …

Review Of Issues Concerning The Use Of Reproductive Inhibitors, With Particular Emphasis On Resolving Human-Wildlife Conflicts In North America, Kathleen A. Fagerstone, Lowell A. Miller, Gary Killian, Christi A. Yoder

United States Department of Agriculture Wildlife Services: Staff Publications

This manuscript provides an overview of past wildlife contraception efforts and discusses the current state of research. Two fertility control agents, an avian reproductive inhibitor containing the active ingredient nicarbazin and an immunocontraceptive vaccine, have received regulatory approval with the Environmental Protection Agency and are commercially available in the USA. OvoControl G Contraceptive Bait for Canada Geese and Ovo Control for pigeons are delivered as oral baits. An injectable immunocontraceptive vaccine (GonaCon Immunocontraceptive Vaccine) was registered with the Environmental Protection Agency for use in female white-tailed deer in September 2009. An injectable product (GonaCon Immunocontraceptive Vaccine) is registered for use …

Evaluation Of Harassment Of Migrating Double-Crested Cormorants To Limit Depredation On Selected Sport Fisheries In Michigan, Brian S. Dorr, Ashley Moerke, Michael Bur, Chuck Bassett, Tony Aderman, Dan Traynor, Russell D. Singleton, Peter H. Butchko, Jimmy D. Taylor Ii

United States Department of Agriculture Wildlife Services: Staff Publications

Diverse management techniques have been used to mitigate conflicts between humans and double-crested cormorants (Phalacrocorax auritus) including harassment methods supplemented by lethal take. In this study we evaluated impacts or programs to harass spring migrating cormorants on the walleye (Sander vitreus) fishery in Brevoort Lake and the yellow perch (Perca flavescens ) and walleye fisheries at Drummond Island. Cormorant foraging declined significantly (p < 0.05) at both locations subsequent to initiation of harassment programs. Overall harassment deteired 90% of cormorant foraging attempts while taking less than 6% lethally on average at each site. Yellow perch were a predominate prey item in number and biomass at both locations. Walleye made up a small proportion of the diet at both locations. However, both walleye and yellow perch abundance increased significantly (p<0.05) at Drummond Island. Walleye abundance at age 3 increased to record levels in 2008 following 3 years of cormorant management at Brevoort Lake. The estimated cormorant consumption of age 1 walleye in the absence of management at Brevoort Lake during 2005 would account for 55% of the record 2006 age 1 walleye population. These results support the hypothesis, that cormorant predation on spawning aggregations of sportfish was a significant mortality factor and cormorant management reduced sportfish mortality and increased abundance at both locations. Continuation of harassment programs and .fishery assessments will determine whether improvement of targeted sport fisheries through control of spring migrating cormorants is sustainable.

Management Effects On Breeding And Foraging Numbers And Movements Of Double-Crested Cormorants In The Les Cheneaux Islands, Lake Huron, Michigan, Brian S. Dorr, Tony Aderrnan, Peter H. Butchko, Scott C. Barras

United States Department of Agriculture Wildlife Services: Staff Publications

The yellow perch fishery of the Les Cheneaux Islands (LCl) region of Lake Huron, MI suffered a collapse in 2000, attributed in part to the increase of double-crested cormorants (Phalocrocorax auritus) in the region. A management program involving egg-oiling and lethal culling was initiated in 2004 to reduce cormorant foraging on yellow perch in the LC1. Counts of cormorant nests, nests oiled, cormorants culled, and aerial counts and telemetry surveys were used to evaluate management. Management contributed to a 74% reduction of cormorants on breeding colonies from 2004 to 2007. Cormorants used the LC1 area significantly more (P<0.05) than surrounding areas. Aerial counts of foraging cormorants declined significantly (P<0.05) over the entire survey area but not within the LCl proper. However, aerial counts of cormorants in the LCI were five-fold less than cormorant counts in the same area in 1995. Reduced cormorant numbers were attributed in part to the elimination of cormorant nesting on a large colony due to the introduction of raccoons. Although the numbers of cormorants using the LC1 did not decline, flocks were significantly smaller and more dispersed after management began. The reduced number of cormorants from 1995 levels and more dispersed foraging likely reduced predation on fish stocks including yellow perch in the LC1. Our findings indicate that the relationship between reduction in cormorant breeding numbers and reduced cormorant foraging in a given area is complex and may be influenced by density dependent factors such as intraspecific competition and quality of the forage base.

Jaguars, Livestock, And People In Brazil: Realities And Perceptions Behind The Conflict, Sandra C. Cavalcanti, Silvio Marchini, Alexandra Zimmermann, Eric M. Gese, David W. Macdonald

United States Department of Agriculture Wildlife Services: Staff Publications

The jaguar (Panthera onca) is the largest predator in the Neotropics and is arguably the most charismatic species for .conservation in Central and South America. Regrettably, the jaguar is also the carnivore that is least compatible with humans in twenty-first century Brazil. This fundamental incompatibility is due to the jaguar's need for abundant, large prey, as well as extensive, undisturbed habitat. Humans (also large, top predators) have competed directly with jaguars for food (i.e. native and domestic ungulates) for as long as they have coexisted (Jorgenson and Redford 1993), and lately threaten them directly and indirectly through deforestation …

An Evaluation Of Diazacon As A Potential Contraceptive In Non-Native Rose-Ringed Parakeets, Mark Lambert, Giovanna Massel, Christi Yoder, David Cowan

United States Department of Agriculture Wildlife Services: Staff Publications

Rose-ringed parakeets (Psittacula krameri) have become widely established outside their native range through accidental or deliberate release. Potential economic impacts on agriculture, conservation concerns, and mixed public opinion regarding the species have highlighted the need to develop effective but humane management options. Fertility control might provide such a solution if a safe and environmentally benign contraceptive was available. The chemical 20,25-diazacholesterol dihydrochloride (diazacon) has previously been used to reduce reproductive output in avian species through reduction of blood cholesterol and cholesterol-dependent reproductive hormones. We orally dosed captive rose-ringed parakeets with a solution of either 9 mg/kg or 18 …

Antibodies To Influenza And West Nile Viruses In Horses In Mexico, M. A. Loroño-Pino, J. A. Farfan-Ale, J. E. Garcia-Rejon, M. Lin, E. Rosado-Paredes, F. I. Puerto, A. Bates, J. J. Root, A. B. Franklin, H. J. Sullivan, B. J. Blitvich

United States Department of Agriculture Wildlife Services: Staff Publications

INFLUENZA A virus (IAV) (family Orthomyxoviridae) is a highly infectious respiratory pathogen of birds and mammals, including human beings and horses (Palese and Shaw 2007). The virus is classified into different subtypes based on the antigenic properties of the haemagglutinin (HA) and neuraminidase (NA) proteins. Sixteen HA subtypes (H1 to H16) and nine NA subtypes (N1 to N9) have been identified (Fouchier and others 2005). Two subtypes, H3N8 and H7N7, have been isolated from horses. The H7N7 subtype was first isolated from a horse in Czechoslovakia in 1956 (Prague/56) (Sovinova and others 1958), and the H3N8 subtype was first isolated …

Fine-Scale Genetic And Social Structuring In A Central Appalachian White-Tailed Deer Herd, Brad F. Miller, Randy W. Deyoung, Tyler A. Campbell, Benjamin R. Laseter, W. Mark Ford, Karl V. Miller

United States Department of Agriculture Wildlife Services: Staff Publications

Spatial genetic structure in white-tailed deer (Odocoileus virginianus) has been examined at regional scales, but genetic markers with the resolution to detect fine-scale patterns have appeared only recently. We used a panel of microsatellite DNA markers, radiotelemetry data, and visual observations of marked deer to study fine-scale social and genetic structure in a high-density population of white-tailed deer (12–20 deer/km²). We collected genetic data on 229 adult females, 102 of which were assigned to 28 social groups. Our results were consistent with the conceptual model of white-tailed deer social structure, where philopatric females form social groups …

Host-Specificity Of Myxoma Virus: Pathogenesis Of South American And North American Strains Of Myxoma Virus In Two North American Lagomorph Species, L. Silvers, D. Barnard, F. Knowlton, B. Inglis, A. Labudovic, M.K. Holland, P.A. Janssens, B.H. Van Leeuwen, P.J. Kerr

United States Department of Agriculture Wildlife Services: Staff Publications

The pathogenesis of South American and North American myxoma viruses was examined in two species of North American lagomorphs, Sylvilagus nuttallii (mountain cottontail) and Sylvilagus audubonii (desert cottontail) both of which have been shown to have the potential to transmit the South American type of myxoma virus. Following infection with the South American strain (Lausanne, Lu), S. nuttallii developed both a local lesion and secondary lesions on the skin. They did not develop the classical myxomatosis seen in European rabbits (Oryctolagus cuniculus). The infection at the inoculation site did not resolve during the 20-day time course of the …

The Versatility Of Graded Acoustic Measures In Classification Of Predation Threats By The Tufted Titmouse Baeolophus Bicolor: Exploring A Mixed Framework For Threat Communication, Kathryn E. Sieving, Stacia A. Hetrick, Michael L. Avery

United States Department of Agriculture Wildlife Services: Staff Publications

Many mammal and bird species respond to predator encounters with alarm vocalizations that generate risk-appropriate responses in listeners. Two conceptual frameworks are typically applied to the information encoded in alarm calls and to associated anti-predator behaviors. ‘Functionally referential’ alarm systems encode nominal classes or categories of risk in distinct call types that refer to distinct predation-risk situations. ‘Risk-based’ alarms encode graded or ranked threat-levels by varying the production patterns of the same call types as the urgency of predation threat changes. Recent work suggests that viewing alarm-response interactions as either referential or risk-based may oversimplify how animals use information in …

Potential Economic Damage From Introduction Of Brown Tree Snakes, Boiga Irregularis (Reptilia: Colubridae), To The Islands Of Hawai‘I, Stephanie A. Shwiff, Karen Gebhardt, Katy N. Kirkpatrick, Steven S. Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

The Brown Tree Snake (Boiga irregularis) has caused ecological and economic damage to Guam, and the snake has the potential to colonize other islands in the Pacific Ocean. This study quantifies the potential economic damage if the snake were translocated, established in the state of Hawaii, and causing damage at levels similar to those on Guam. Damages modeled included costs of medical treatments due to snakebites, snake-caused power outages, and decreased tourism resulting from effects of the snake. Damage caused by presence of the Brown Tree Snake on Guam was used as a guide to estimate potential economic …

Polyurea Elastomer Protects Utility Pole Crossarms From Damage By Pileated Woodpeckers, Shelagh Tupper, William Andelt, John Cummings, Charles Weisner, Richard Harness

United States Department of Agriculture Wildlife Services: Staff Publications

Woodpeckers cause severe damage to utility poles and crossarms, resulting in substantial economic losses to utility companies. We evaluated effectiveness of a polyurea elastomer coating material for reducing damage by captive pileated woodpeckers (Dryocopus pileatus) to utility pole crossarms. Because woodpeckers inflicted essentially no damage to the fully coated crossarms, we infer that the coating material holds substantial promise for protecting utility pole crossarms. Additional research should be conducted to evaluate the coating under field conditions.

Evaluation Of Christmas Bird Counts And Landscape Factors As Indicators Of Local Blackbird And European Starling Winter Roosts, Matthew Strassburg, George M. Linz, William Bleier

United States Department of Agriculture Wildlife Services: Staff Publications

Red-winged blackbirds (RWBL) and common grackles (COGR) are the two most abundant blackbird species on the continent; Brewer's blackbirds (BRBL) are a much less common, but closely related species, and along with European starlings (EUST), they are two of the most common groups of birds in North America, with combined populations that reach into the several hundreds of millions and make up a significant portion of the avian population (Yasukawa and Searcy 1995). Although the most common bird on the continent, certain regions have seen declines in RWBL for a number of decades. In Ohio and North Dakota, this has …

Increased Risk Of Chronic Wasting Disease In Rocky Mountain Elk Associated With Decreased Magnesium And Increased Manganese In Brain Tissue, Stephen N. White, Katherine I. O’Rourke, Thomas Gidlewski, Kurt C. Vercauteren, Michelle R. Mousel, Gregory E. Phillips, Terry R. Spraker

United States Department of Agriculture Wildlife Services: Staff Publications

Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy (TSE) of Rocky Mountain elk in North America. Recent studies suggest that tissue and blood mineral levels may be valuable in assessing TSE infection in sheep and cattle. The objectives of this study were to examine baseline levels of copper, manganese, magnesium, zinc, selenium, and molybdenum in the brains of Rocky Mountain elk with differing prion genotypes and to assess the association of mineral levels with CWD infection. Elk with leucine at prion position 132 had significantly lower magnesium levels than elk with 2 copies of methionine. Chronic wasting disease-positive elk …

Potential Attractants For Detecting And Removing Invading Gambian Giant Pouched Rats (Cricetomys Gambianus), Gary W. Witmer, Nathan P. Snow, Patrick Burke

United States Department of Agriculture Wildlife Services: Staff Publications

BACKGROUND: Native to Africa, Gambian giant pouched rats (Gambian rats; Cricetomys gambianus Waterh.) are a threatening invasive species on a Florida island, Grassy Key. Gambian giant pouched rats shifted from a domestic pet to invading species after suspected release from a pet breeder. Because of the large size of Gambian rats (weighing up to 2.8 kg), they pose a serious threat to native species (particularly nesting species) and agricultural crops, especially if Gambian rats invade mainland Florida. Also, Gambian rats pose a threat from disease, as they were implicated in a monkeypox outbreak in the mid-western United States in 2003. …

S-Nitrosothiols: Formation, Decomposition, Reactivity And Possible Physiological Effects, Moshood Kayode Morakinyo

Dissertations and Theses

Three biologically-active aminothiols cysteamine (CA), DL-cysteine (CYSH) and DL-homocysteine, were studied in this thesis. These aminothiols react with nitrous acid (HNO₂), prepared in situ, to produce S-nitrosothiols (RSNOs): S-nitrosocyteamine (CANO), S-nitrosocysteine (CYSNO) and S-nitrosohomocysteine (HCYSNO). They also react with S-nitrosoglutathione (GSNO) and S-nitroso-N-acetylpenicillamine (SNAP) through a transnitrosation reaction to produce their corresponding RSNOs. A detailed kinetics and mechanistic study on the formation of these RSNOs and their subsequent decomposition to release nitric oxide (NO) were studied.

For all three aminothiols the stoichiometry of their reaction with nitrous acid is strictly 1:1 with the formation of one mole …

An Inventory And Condition Survey Of The Western Australian Part Of The Nullarbor Region, Peter-Jon A. Waddell, A K. Gardner, P Hennig

Technical Bulletins

The inventory and condition survey of the Western Australian part of the Nullarbor region, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 2005 and 2007, describes and maps the natural resources of the region. This survey report provides a baseline record of the existence and condition of the area's natural resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The Nullarbor region has …

A Methodology To Estimate The Future Extent Of Dryland Salinity In The Southwest Of Western Australia, Peter Caccetta, Robert Dunne, Richard J. George, Don J. Mcfarlane

Natural Resources Research Articles

In the southwestern agricultural region of Western Australia, the clearing of the original perennial vegetation for annual vegetation-based dryland agriculture has lead to rising saline groundwater levels. This has had effects such as reduced productivity of agricultural land, death of native vegetation, reduced stream water quality and infrastructure damage. These effects have been observed at many locations within the 18 million ha of cleared land. This has lead to efforts to quantify, in a spatially explicit way, the historical and likely future extent of the area affected, with the view to informing management decisions. This study was conducted to determine …