Movements of Feral Hogs in Response to Warfarin Bait Consumption

The distribution of feral hogs throughout North American has increased dramatically since their introduction. The use of toxicants has proven to be a n effective tool in controlling feral hog numbers in several countries. Using data from 13 GPS hogs, we compared movements and space use of control and treated hogs between pre-baiting and baiting phases of 3 feral hog toxicant field tests. Generalized linear mixed models were used to explain prospective changes in movements. In addition, we evaluated the distance of toxicant-killed feral hog carcasses from bait stations, roads, and cultivated crop plots. The mean distances traveled by treatment hogs between the pre-baiting and baiting periods was reduced by 43.9%, 32.1%, and 48.8% for daily, diurnal, and nocturnal periods, respectively. Daily and nocturnal movements exhibited a significant decrease between pre-baiting and baiting phases by feral hogs as a result of bait consumption. Mean space use size between the pre-baiting and baiting periods for treatment hogs was reduced by 37.5% and 30.0% for 95% MCP and 50% MCP, respectively but was not a result of bait consumption. Toxicant-killed feral hog carcass distance from bait stations, cultivated crops, and roads averaged (± SE) 919.4 ± 68.1 m, 908.9 ± 72.1 m, and 120.7 ± 34.9 m, respectively. These carcasses were never recovered from crop plots or near roads and were typically found in natural land cover types. The toxicant warfarin reduced movements of feral hogs, which in turn can reduce their damage to crop and reduce the spread of disease

Movements of Feral Hogs in Response to Warfarin Bait Consumption

The distribution of feral hogs throughout North American has increased dramatically since their introduction. The use of toxicants has proven to be a n effective tool in controlling feral hog numbers in several countries. Using data from 13 GPS hogs, we compared movements and space use of control and treated hogs between pre-baiting and baiting phases of 3 feral hog toxicant field tests. Generalized linear mixed models were used to explain prospective changes in movements. In addition, we evaluated the distance of toxicant-killed feral hog carcasses from bait stations, roads, and cultivated crop plots. The mean distances traveled by treatment hogs between the pre-baiting and baiting periods was reduced by 43.9%, 32.1%, and 48.8% for daily, diurnal, and nocturnal periods, respectively. Daily and nocturnal movements exhibited a significant decrease between pre-baiting and baiting phases by feral hogs as a result of bait consumption. Mean space use size between the pre-baiting and baiting periods for treatment hogs was reduced by 37.5% and 30.0% for 95% MCP and 50% MCP, respectively but was not a result of bait consumption. Toxicant-killed feral hog carcass distance from bait stations, cultivated crops, and roads averaged (± SE) 919.4 ± 68.1 m, 908.9 ± 72.1 m, and 120.7 ± 34.9 m, respectively. These carcasses were never recovered from crop plots or near roads and were typically found in natural land cover types. The toxicant warfarin reduced movements of feral hogs, which in turn can reduce their damage to crop and reduce the spread of disease

Field Testing of a New Feral Hog Feeder to Minimize Bait Exposure to Non-target Wildlife

The feral hog is an invasive species that inflicts billions of dollars in agricultural damage every year in the U.S. Hog-specific baits have shown promise in reducing feral hog abundance but require species-specific feeders to exclude domestic animals and non-target wildlife. Four feeder types were tested during 2016 and 2017 field studies, including commercial feeders, prototype feeders, and a new species-specific feral hog feeder. Commercial feeders with 2.3 kg, 4.5 kg, and 6.8 kg weighted doors were used in 2016 and raccoons were observed on camera opening doors 10 times out of 164 camera observed visitations (6.1%). No other non-target species were observed entering the feeders. The following year, new feeders with 7.7 kg double-sided guillotine doors were used in a field study and no raccoons opened doors during 153 camera-observed visitations. Out of over 1,600 non-target camera images recorded, only one mouse was observed inside the feeders. Results of this study suggest the new hog feeder may provide reduced-risk to non-target species and a promising tool for controlling hog populations

Pathogenic variation of Pyrenophora teres f. teres in Australia

Pyrenophora teres f. teres (Ptt) is the causal agent of net form of net blotch (NFNB) – a major foliar disease of barley (Hordeum vulgare) crops worldwide. Deployment of genetic resistance in cultivars is the preferred method of control, but requires knowledge of the pathogenic variation of Ptt to be effective as spatial and temporal variation is common. In this study, 123 Ptt isolates collected from five states across Australia were examined for pathogenic variation using a set of 31 barley genotypes, composed of 11 international genotypes and 20 Australian cultivars. Barley seedlings were inoculated with spore suspensions from monoconidial isolate cultures and scored for infection response. Phenotypes were used to perform hierarchical cluster analysis for barley genotypes and Ptt isolates. Cluster analysis identified seven line groups, each containing barley genotypes that displayed similar responses to the Ptt isolates. Isolates clustered into four distinct isolate groups shown to harbour differential virulence to four key genotypes: Maritime, Prior, Skiff and Tallon. Isolates with virulence to any one of these genotypes accounted for 96.7% of the samples. Differential virulence was observed on a range of genotypes within each isolate group. The composition of isolate groups in eastern Australia was distinct from Western Australia, whereas all isolate groups were detected in southern Australia. Results suggest that cultivation of regionally adapted barley cultivars has led to regional evolution of Ptt, where the pathogen acquires virulence specific for resistance factors deployed in local cultivars. Detection of Ptt modern isolates that were highly virulent to historic cultivars indicates the long-term survival of virulence gene combinations in the pathogen population

Characterisation of Rph24: a gene conferring adult plant resistance to Puccinia hordei in barley

We identified Rph24 as a locus in barley (Hordeum vulgare L.) controlling adult plant resistance (APR) to leaf rust, caused by Puccinia hordei. The locus was previously reported as a quantitative trait locus in barley line ND24260-1 and named qRphND. We crossed ND24260-1 to the leafrust- susceptible standard Gus and determined inheritance patterns in the progeny. For the comparative marker frequency analysis (MFA), resistant and susceptible tails of the F2 were genotyped with Diversity Arrays Technology genotyping-by-sequencing (DArT-Seq) markers. The Rph24 locus was positioned at 55.5 centimorgans on chromosome 6H on the DArT-Seq consensus map. Evaluation of F2:3 families confirmed that a single locus from ND24260-1 conferred partial resistance. The haploblock strongly associated with the Rph24 locus was used to estimate the allele frequency in a collection of 282 international barley cultivars. Rph24 was frequently paired with APR locus Rph20 in cultivars displaying high levels of APR to leaf rust. The markers identified in this study for Rph24 should be useful for marker-assisted selection