Electric Fences and Poison Buffers as Barriers to Movements and Dispersal of Brushtail Possums (Trichosurus Vulpecula) on Farmland.

1993 ◽  
Vol 20 (5) ◽  
pp. 671 ◽  
Author(s):  
PE Cowan ◽  
DS Rhodes
Keyword(s):  
Bovine Tuberculosis ◽  
Average Distance ◽  
Buffer Zone ◽  
Control Site ◽  
Trichosurus Vulpecula ◽  
Buffer Zones ◽  
North West ◽  
North East ◽  
Live Trapping ◽  
Electric Fence

Limitation of the spread of bovine tuberculosis by brushtail possums (Trichosurus vulpecula) in New Zealand involves creating buffer zones 3-5km wide around areas where the disease is endemic in possum populations; low possum density is established by aerial and ground poisoning and maintained by repeated control. The effectiveness of a buffer zone was examined using live-trapping and radiotracking to study movements and dispersal of juvenile and adult possums in comparison with a nearby, undisturbed (control) site. At a third site, the effect of a 3-km long, 9-strand electric fence, erected from ridge to ridge across a valley catchment, for reducing possum dispersal was measured, as an alternative to a buffer zone. Adult possums were highly sedentary; only one permanent shift of more than 0.5km was detected during repeated live-trapping and radio-tracking, and most consecutive live captures were in traps less than 200m apart. None of the radio-tagged adults adjacent to the poison buffer zones moved permanently into the low-density areas. By contrast, about 20% of radio-tagged juveniles dispersed more than 0.5km, moving up to 11.6km from their natal areas, most in a generally west-north-west to east-north-east direction. About equal numbers dispersed upstream, downstream, or in other directions. Significantly more males dispersed than females, but their dispersal distances were similar. Some dispersing possums moved more than 2km overnight, and females, particularly, often made several moves before settling. Most juveniles dispersed before they were one year old, mainly in the three months immediately preceding the peak of births in autumn. Neither the poison buffer zone nor the electric fence appeared to influence the proportion of juveniles that dispersed more than 0.5km, or the average distance dispersed. The implications of these findings in preventing the spread of bovine tuberculosis are discussed.

Restricting the movements of brushtail possums (Trichosurus vulpecula) on farmland with electric fencing

1992 ◽  
Vol 19 (1) ◽  
pp. 47 ◽  
Author(s):  
PE Cown ◽  
DS Rhodes
Keyword(s):  
New Zealand ◽  
Bovine Tuberculosis ◽  
Trichosurus Vulpecula ◽  
Electric Fence ◽  
Electric Fencing

A trial was conducted to test whether an electric fence would limit local movements of brushtail possums (Trichosurus vulpecula) on farmland in the central North I. of New Zealand. If effective, such a system could be used to reduce possum and cattle interactions and the spread of bovine tuberculosis. A 3-km-long, 9-strand electric fence was erected from ridge to ridge across a valley catchment of about 160 ha. Possums were live-trapped and released at bush patches within the study area and in open areas immediately adjacent to the electric fence. Only about 30% of possums caught at local bush patches were ever retrapped at the fence, and most were caught only once at the fence. About a third of possums caught at the fence were trapped at least once on both sides of the fence. The electric fence reduced possum movements through the fenced area by about 60-80%. Most possums trapped at the fence had come from bush patches within 200 m of the fence. When the fence was switched off, possum captures on the outside increased rapidly. The effectiveness of the fence was reduced because of frequent voltage reduction by earthing from a wide variety of causes, and because possums learned to move around the ends of the fence and the fences along the farm roads. Improvements to fence design are discussed.

scholarly journals Assessing effects from four years of industry-led badger culling in England on the incidence of bovine tuberculosis in cattle, 2013–2017

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Sara H. Downs ◽  
Alison Prosser ◽  
Adam Ashton ◽  
Stuart Ashfield ◽  
Lucy A. Brunton ◽  
...  
Keyword(s):  
Incidence Rate ◽  
Bovine Tuberculosis ◽  
Incidence Rate Ratio ◽  
Central Zone ◽  
Buffer Zone ◽  
Incidence Rates ◽  
Buffer Zones ◽  
Badger Culling ◽  
Cattle Herds ◽  
Farming Industry

Abstract The objective was to measure the association between badger culling and bovine tuberculosis (TB) incidents in cattle herds in three areas of England between 2013–2017 (Gloucestershire and Somerset) and 2015–2017 (Dorset). Farming industry-selected licensed culling areas were matched to comparison areas. A TB incident was detection of new Mycobacterium bovis infection (post-mortem confirmed) in at least one animal in a herd. Intervention and comparison area incidence rates were compared in central zones where culling was conducted and surrounding buffer zones, through multivariable Poisson regression analyses. Central zone incidence rates in Gloucestershire (Incidence rate ratio (IRR) 0.34 (95% CI 0.29 to 0.39, p < 0.001) and Somerset (IRR 0.63 (95% CI 0.58 to 0.69, p < 0.001) were lower and no different in Dorset (IRR 1.10, 95% CI 0.96 to 1.27, p = 0.168) than comparison central zone rates. The buffer zone incidence rate was lower for Gloucestershire (IRR 0.64, 95% CI 0.58 to 0.70, p < 0.001), no different for Somerset (IRR 0.97, 95% CI 0.80 to 1.16, p = 0.767) and lower for Dorset (IRR 0.45, 95% CI 0.37 to 0.54, p < 0.001) than comparison buffer zone rates. Industry-led culling was associated with reductions in cattle TB incidence rates after four years but there were variations in effects between areas.

Buffer zones promoting oligotrophication in golf course runoffs: fiddler crabs as estuarine health indicators

2001 ◽  
Vol 44 (11-12) ◽  
pp. 591-598 ◽  
Author(s):  
R.Y. George ◽  
G. Bodnar ◽  
S.L. Gerlach ◽  
R.M. Nelson
Keyword(s):  
Constructed Wetlands ◽  
Fiddler Crab ◽  
Health Indicators ◽  
Buffer Zone ◽  
Threshold Level ◽  
Control Site ◽  
Golf Course ◽  
Estuarine Ecosystem ◽  
Buffer Zones ◽  
The University

Nitrogen pollution above a threshold level induces a eutrophication process in coastal creek ecosystems and consequently impacts on the water quality. The remedy for this scenario is the introduction of methods to enhance oligotrophication by means of constructed wetlands and buffer zones. This paper discusses new data on nitrogen flux and population changes in the primary consumers in the Bradley Creek ecosystem, adjacent to the Duck Haven Golf Course in southeastern North Carolina. In 1998-99, over different seasons, density distribution of the field populations of the fiddler crab Uca minax, was monitored as an indicator of environmental health. A control site at Whiskey Creek, adjacent to the University Center for Marine Sciences, was monitored in the same period since this site is not influenced by any golf course nutrient flux. The results pointed out that threshold level for optimum population density in Spartina grandiflora salt marsh is 0.1 mg/L of nitrates. A dense crab population, adjacent to the golf course with a buffer zone, was indicative of restoration of the estuarine ecosystem. A model, involving the use of constructed wetlands for oligotrophication, is being prepared on the basis of studies conducted by the University of South Alabama for a stormwater wetland constructed adjacent to the university's golf course.

The effect of poisoned and notional vaccinated buffers on possum (Trichosurus vulpecula) movements: minimising the risk of bovine tuberculosis spread from forest to farmland

2010 ◽  
Vol 37 (4) ◽  
pp. 283 ◽  
Author(s):  
R. Pech ◽  
A. Byrom ◽  
D. Anderson ◽  
C. Thomson ◽  
M. Coleman
Keyword(s):  
Bovine Tuberculosis ◽  
Cost Effective ◽  
Acceptable Level ◽  
Disease Spread ◽  
Initial Population ◽  
Home Ranges ◽  
Trichosurus Vulpecula ◽  
Buffer Zones ◽  
Lethal Control ◽  
Forest Buffer

Context. Vaccination of brushtail possums (Trichosurus vulpecula) has been proposed as a cost-effective alternative to lethal control for preventing potentially bovine tuberculosis (Tb)-infected possums from crossing forested buffer zones that abut farmland. Aim. Evaluation of these two management option requires an estimation of the buffer width required to reduce the risk of disease spread to an acceptable level. Methods. The movements of two groups of adult and subadult possums were monitored for up to 12 months in the Kaimanawa Range, North Island of New Zealand, using GPS technology. One group was in untreated forest immediately adjacent to a recently poisoned forest buffer, and the second group was 2 km further into untreated forest, which mimicked a vaccinated buffer with no reduction in possum abundance. Key results. Close to the poisoned buffer, where the initial population density was 0.49–1.45 ha–1, adult possum home ranges averaged 10.2 ha in the summer immediately after control and 9.5 ha in the following winter. Two kilometres into the untreated forest, where the density was >3 ha–1, the corresponding values were only 3.5 ha and 2.8 ha. Over the first 6 months of monitoring, a ~350-m wide poisoned buffer would have contained 95% of movements by adult possums, as well as movements by most individuals, but a ~150-m wide vaccinated buffer would have been as effective. Equivalent results for the subsequent 6-month period were ~450 m and ~200 m for poisoned and vaccinated buffers, respectively. Movements by possums were not biased in the direction of the population ‘vacuum’ created by the poisoning operation. When subadult possums were included in the analysis, buffer widths of ~500–600 m for both poisoning and vaccination would be required to contain 95% of new den site locations. Conclusions and implications. Detailed data on possum movements provide a means for agencies managing Tb to specify the width of a buffer, subject to an acceptable level of risk that it could be breached by a potentially infected possum. As well as depending on the width of a treated buffer, the final cost-effectiveness of vaccination compared with poisoning will depend on the relative cost of applying the two control techniques, and the frequency of application required either to prevent Tb from establishing (in the case of vaccination) or to suppress possum density (in the case of lethal control).

scholarly journals Non-volant mammal inventory of Cusuco National Park, north-west Honduras: reporting the presence of Jaguar, Panthera onca (Linnaeus, 1758), and demonstrating the effects of zonal protection on mammalian abundance

Check List ◽  
2018 ◽  
Vol 14 (5) ◽  
pp. 877-891
Author(s):  
Hannah M. J. Hoskins ◽  
Oliver J. Burdekin ◽  
Kara Dicks ◽  
Kathy Y. Slater ◽  
Niall P. McCann ◽  
...  
Keyword(s):  
National Park ◽  
Buffer Zone ◽  
Central American ◽  
Panthera Onca ◽  
Mammal Species ◽  
Protection Measures ◽  
North West ◽  
Live Trapping ◽  
A Site ◽  
The Impact

Neotropical cloud forests are one of the most biodiverse yet threatened ecosystems with deforestation and hunting creating major problems. We report a non-volant mammal species inventory for Cusuco National Park, Honduras, spanning 2006–2016. Data were collected using 4 methods: tracks and signs, camera trapping, direct sightings and live trapping. Recorded species of conservation importance included Central American red brocket (Mazama temama (Kerr, 1792)), Baird’s tapir (Tapirus bairdii (Gill, 1865)), margay (Leopardus wiedii (Schinz, 1821)), and jaguar (Panthera onca (Linnaeus, 1758)); the latter recorded for the first time. Cusuco National Park is a site of strategic geographical importance within the Central American jaguar corridor. In total, 43 species were recorded from 26 families. We demonstrate the impact of zonal protection measures with higher mammal abundance recorded in the park’s highly protected core compared to the less protected buffer zone. We advise continued monitoring to provide robust time-series of population trends.

A new volcanic province: evidence from glacial erratics in western North Greenland

2000 ◽  
pp. 35-41 ◽  
Author(s):  
Peter R. Dawes ◽  
Bjørn Thomassen ◽  
T.I. Hauge Andersson
Keyword(s):  
Volcanic Rocks ◽  
Iron Formation ◽  
Banded Iron Formation ◽  
Common Component ◽  
Volcanic Province ◽  
North West ◽  
North East ◽  
The North ◽  
Surficial Deposits ◽  
North Greenland

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Dawes, P. R., Thomassen, B., & Andersson, T. H. (2000). A new volcanic province: evidence from glacial erratics in western North Greenland. Geology of Greenland Survey Bulletin, 186, 35-41. https://doi.org/10.34194/ggub.v186.5213 _______________ Mapping and regional geological studies in northern Greenland were carried out during the project Kane Basin 1999 (see Dawes et al. 2000, this volume). During ore geological studies in Washington Land by one of us (B.T.), finds of erratics of banded iron formation (BIF) directed special attention to the till, glaciofluvial and fluvial sediments. This led to the discovery that in certain parts of Daugaard-Jensen Land and Washington Land volcanic rocks form a common component of the surficial deposits, with particularly colourful, red porphyries catching the eye. The presence of BIF is interesting but not altogether unexpected since BIF erratics have been reported from southern Hall Land just to the north-east (Kelly & Bennike 1992) and such rocks crop out in the Precambrian shield of North-West Greenland to the south (Fig. 1; Dawes 1991). On the other hand, the presence of volcanic erratics was unexpected and stimulated the work reported on here.

Stratigraphy, structure and geochemistry of Archaean supracrustal rocks from Oqaatsut and Naajaat Qaqqaat, north-east Disko Bugt, West Greenland

1999 ◽  
pp. 65-78
Author(s):  
Henrik Rasmussen ◽  
Lars Frimodt Pedersen
Keyword(s):  
Tectonic Setting ◽  
Trace Element Geochemistry ◽  
Element Geochemistry ◽  
West Greenland ◽  
North West ◽  
North East ◽  
Metavolcanic Rocks ◽  
Arc Setting ◽  
Area North ◽  
Back Arc

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Rasmussen, H., & Frimodt Pedersen, L. (1999). Stratigraphy, structure and geochemistry of Archaean supracrustal rocks from Oqaatsut and Naajaat Qaqqaat, north-east Disko Bugt, West Greenland. Geology of Greenland Survey Bulletin, 181, 65-78. https://doi.org/10.34194/ggub.v181.5114 _______________ Two Archaean supracrustal sequences in the area north-east of Disko Bugt, c. 1950 and c. 800 m in thickness, are dominated by pelitic and semipelitic mica schists, interlayered with basic metavolcanic rocks. A polymict conglomerate occurs locally at the base of one of the sequences. One of the supracrustal sequences has undergone four phases of deformation; the other three phases. In both sequences an early phase, now represented by isoclinal folds, was followed by north-west-directed thrusting. A penetrative deformation represented by upright to steeply inclined folds is only recognised in one of the sequences. Steep, brittle N–S and NW–SE striking faults transect all rock units including late stage dolerites and lamprophyres. Investigation of major- and trace-element geochemistry based on discrimination diagrams for tectonic setting suggests that both metasediments and metavolcanic rocks were deposited in an environment similar to a modern back-arc setting.

scholarly journals Radio Base Stations and Electromagnetic Fields: GIS Applications and Models for Identifying Possible Risk Factors and Areas Exposed. Some Exemplifications in Rome

2020 ◽  
Vol 10 (1) ◽  
pp. 3
Author(s):  
Cristiano Pesaresi ◽  
Davide Pavia
Keyword(s):  
Risk Factors ◽  
Electromagnetic Fields ◽  
Digital Health ◽  
Three Dimensional ◽  
Health Information System ◽  
Medical Geography ◽  
Base Stations ◽  
Buffer Zones ◽  
North East ◽  
Gis Applications

This paper—which is contextualized in the discussion on the methodological pluralism and the main topics of medical geography, the complexity theory in geographies of health, the remaking of medical geography and ad hoc systems of data elaboration—focuses on radio base stations (RBSs) as sources of electromagnetic fields, to provide GIS applications and simplifying-prudential models that are able to identify areas that could potentially be exposed to hazard. After highlighting some specific aspects regarding RBSs and their characteristics and summarizing the results of a number of studies concerning the possible effects of electromagnetic fields on health, we have taken an area of north-east Rome with a high population and building density as a case study, and we have provided some methodological and applicative exemplifications for different situations and types of antennas. Through specific functionalities and criteria, drawing inspiration from a precautionary principle, these exemplifications show some particular cases in order to support: possible risk factor identification, surveillance and spatial analysis; correlation analysis between potential risk factors and outbreak of diseases and symptoms; measurement campaigns in heavily exposed areas and buildings; education policies and prevention actions. From an operative viewpoint, we have: conducted some field surveys and recorded data and images with specific geotechnological and geomatics instruments; retraced the routes by geobrowsers and basemaps and harmonized and joined up the materials in a GIS environment; used different functions to define, on aero-satellite images, concentric circular buffer zones starting from each RBS, and geographically and geometrically delimited the connected areas subject to high and different exposure levels; produced digital applications and tested prime three-dimensional models, in addition to a video from a bird’s eye view perspective, able to show the buildings in the different buffer zones and which are subject to a hazard hierarchy due to exposure to an RBS. A similar GIS-based model—reproposable with methodological adjustments to other polluting sources—can make it possible to conceive a dynamic and multiscale digital system functional in terms of strategic planning, decision-making and public health promotion in a performant digital health information system.

scholarly journals DISTRIBUTION AND RACE COMPOSITION OF DOWNY MILDEW (Plasmopara halstedii (Farl.) Berl. and de Toni) IN BULGARIA / EXTENSION Y RAZAS DEL MILDIU (Plasmopara halstedii (Farl.) Berl. y de Toni) EN BULGARIA / ÉTENDUE ET RACES DE LA ROUILLE (Plasmopara halstedii (Farl.) Berl. and de Toni) EN BULGARIE

Helia ◽  
2000 ◽  
Vol 23 (33) ◽  
pp. 25-32
Author(s):  
P.S. Shindrova
Keyword(s):  
Downy Mildew ◽  
Resistance Gene ◽  
The Other ◽  
Plasmopara Halstedii ◽  
North West ◽  
North East ◽  
Race 1 ◽  
Race 2 ◽  
Production Areas ◽  
Number Of Authors

SUMMARY Downy mildew caused by the fungus Plasmopara halstedii is the main disease on sunflower in Bulgaria. In recent years a number of authors have reported the occurrence of new more virulent races of the pathogen. According to other authors these races demonstrate resistance to the fungicides used up to now. This fact is rather alarming and imposes the necessity of annual researches with the aim of following the changes in the downy mildew race variability. In the period 1995-1997 downy mildew isolates were collected from the following locations: Bourgas, Boyanovo, Karnobat, Ognyanovo, Selanovtsi, Kroushari, Lovech, Koubrat, Brashlyan, Sitovo, Tervel, Targovishte, IWS “Dobroudja” and Dobrich. The samples were assessed for virulence on a set of sunflower differential - lines under greenhouse conditions. The obtained results do not reveal a great race variability of downy mildew population in Bulgaria. In the period of study two races of the pathogen were identified: race 1 which infects the differential lines without genes for resistance to the pathogen. It is distributed in all sunflower production areas of the country. The other one is race 2. It is of limited distribution and has been registered in individual fields of north-east and north-west Bulgaria. It attacks the differential lines carrying the resistance gene Pl-1.

Excavations at Fishbourne, 1963. Third Interim Report

1964 ◽  
Vol 44 (1) ◽  
pp. 1-8
Keyword(s):  
Interim Report ◽  
The West ◽  
Civic Society ◽  
North West ◽  
The Third ◽  
North East ◽  
The North ◽  
The Future ◽  
Set Up

Early in 1963 much of the land occupied by the Roman building at Fishbourne was purchased by Mr. I. D. Margary, M.A., F.S.A., and was given to the Sussex Archaeological Trust. The Fishbourne Committee of the trust was set up to administer the future of the site. The third season's excavation, carried out at the desire of this committee, was again organized by the Chichester Civic Society.1 About fifty volunteers a day were employed from 24th July to 3rd September. Excavation concentrated upon three main areas; the orchard south of the east wing excavated in 1962, the west end of the north wing, and the west wing. In addition, trial trenches were dug at the north-east and north-west extremities of the building and in the area to the north of the north wing. The work of supervision was carried out by Miss F. Pierce, M.A., Mr. B. Morley, Mr. A. B. Norton, B.A., and Mr. J. P. Wild, B.A. Photography was organized by Mr. D. B. Baker and Mrs. F. A. Cunliffe took charge of the pottery and finds.

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