When, where and why do people encounter Australian brownsnakes (Pseudonaja textilis : Elapidae)?

1999 ◽  
Vol 26 (5) ◽  
pp. 675 ◽  
Author(s):  
P. B. Whitaker ◽  
R. Shine
Keyword(s):  
Air Temperature ◽  
Agricultural Land ◽  
New South ◽  
Habitat Type ◽  
Weather Conditions ◽  
Time Of Day ◽  
South Wales ◽  
Experienced Observer ◽  
Close Proximity ◽  
Species Ecology

Encounters between humans and dangerously venomous snakes put both participants at serious risk, so the determinants of such encounters warrant attention. Pseudonaja textilis is a large fast-moving elapid snake responsible for most snakebite fatalities in Australia. As part of a broad ecological study of this species in agricultural land near Leeton, New South Wales, we set out to identify factors influencing the probability that a human walking in farmland would come into close proximity to a brownsnake. Over a three-year period, we walked regular transects to quantify the number and rate of snake encounters, and the proportion of snakes above ground that could be seen. The rate of encounters depended upon a series of factors, including season, time of day, habitat type, weather conditions (wind and air temperature) and shade (light v. dark) of the observers’ clothing. Interactions between factors were also important: for example, the effect of air temperature on encounter probability differed with season and snake gender, and the effect of the observers’ shade of clothing differed with cloud cover. Remarkably, even a highly-experienced observer actually saw <25% of the telemetrically monitored snakes that were known to be active (i.e. above ground) nearby. This result reflects the snakes’ ability to evade people and to escape detection, even in the flat and sparsely vegetated study area. The proportion of snakes that were visible was influenced by the same kinds of factors as described above. Most of the factors biasing encounter rates are readily interpretable from information on other facets of the species’ ecology, and knowledge of these factors may facilitate safer coexistence between snakes and people.

The effects of age, sex, reproductive status and temporal factors on the time-use of free-ranging red kangaroos

1993 ◽  
Vol 20 (6) ◽  
pp. 785 ◽  
Author(s):  
DM Watson ◽  
TJ Dawson
Keyword(s):  
Body Size ◽  
Group Size ◽  
Time Use ◽  
New South ◽  
New South Wales ◽  
Time Of Day ◽  
Adult Males ◽  
South Wales ◽  
Free Ranging ◽  
Foraging Time

The effects of temporal (time of day and season) factors and size, sex, female reproductive state and group size on the diel time-use of free-ranging red kangaroos (Macropus rufus) was examined. Particular emphasis was given to the effects on their foraging behaviour, with foraging divided into cropping, chewing and searching components. The study was conducted in semi-arid western New South Wales from July 1991 to March 1992, a time of deepening drought conditions in New South Wales. Group size had very little influence on the time-use of M. rufus. It was negatively but only weakly correlated with the proportion of foraging time spent chewing (chewing intensity). No significant differences in time-use were found between size classes of adult males (large and medium-sized males), females with or without pouch young, or females with different-sized pouch young (no visible young, small pouch young or large pouch young). Differences occurred between adult males, adult females and subadult kangaroos. These differences were mainly associated with their chewing and searching behaviour and were related to body size; as body size increased the proportion of time spent chewing and the intensity of chewing increased while the proportion of time searching and the proportion of foraging time spent searching (searching intensity) decreased. Neither the proportion of time spent cropping or foraging nor the proportion of foraging time spent cropping (cropping intensity) or the proportion of active time spent foraging (foraging intensity) differed between any size/sex/reproductive class. Temporal effects had a considerable influence on time-use. M. rufus were most active at night and in the few hours after sunrise and sunset. Seasonal changes in time-use were largely a result of changes in daytime behaviour. M. rufus foraged less and rested more during the day in winter than in spring or summer. There was no increase in the intensity or proportion of time spent foraging or cropping at night to compensate for the reduction in diurnal foraging. It is hypothesised that temporal variations in time-use were related to variations in weather and vegetation conditions.

Temporal, spatial and individual variation in the diet of red foxes (Vulpes vulpes) in central New South Wales

2000 ◽  
Vol 27 (6) ◽  
pp. 593 ◽  
Author(s):  
R. L. Molsher ◽  
E. J. Gifford ◽  
J. C. McIlroy
Keyword(s):  
Individual Variation ◽  
Vulpes Vulpes ◽  
Agricultural Land ◽  
New South ◽  
New South Wales ◽  
Ovis Aries ◽  
Red Foxes ◽  
Moon Phases ◽  
Temporal Synchrony ◽  
South Wales

This study describes temporal, spatial and individual variation in the diet of 255 red foxes (Vulpes vulpes) collected from agricultural land in central New South Wales from July 1994 to November 1996. Rabbits (Oryctolagus cuniculus), sheep (Ovis aries), eastern grey kangaroos (Macropus giganteus) and invertebrates were the most important food items overall. Significant seasonal variations, and sex and age differences between foxes occurred in the consumption of some food types. Some temporal synchrony was also evident, with different individuals often eating similar foods on the same night. This may have been related to moonlight. On full moon nights, foxes ate rabbits and small mammals significantly less often than during other moon phases. The management implications of variation in diet are discussed.

Life under a sandstone overhang: the ecology of the eastern cave bat Vespadelus troughtoni in northern New South Wales.

2005 ◽  
Vol 27 (2) ◽  
pp. 137 ◽  
Author(s):  
B Law ◽  
M Chidel ◽  
A Mong
Keyword(s):  
New South ◽  
New South Wales ◽  
Rural Landscape ◽  
Native Vegetation ◽  
Radio Tracking ◽  
Tree Hollows ◽  
South Wales ◽  
Close Proximity ◽  
Air Space ◽  
Forested Areas

We studied the eastern cave bat (Vespadelus troughtoni) in northern New South Wales to provide ecological information on roosts and foraging. Radio-tracking of five bats was supplemented with opportunistic visits to roosts over five years. One male was radio-tracked and its roost was within a corrugated iron roof cavity of a dairy. Maternity roosts were located in the overhangs of large sandstone caves usually containing a dome at the rear. Searches of nearby cliff-lines found that small caves, crevices and overhangs were not used as day-roosts. Nor did any radio-tagged bat roost in tree hollows. Colony size of one tight roosting cluster was estimated as 240 individuals. Radio-tagged bats frequently switched roosts, while opportunistic visits over a five-year period often found caves unoccupied. Most movements between roosts were within 1.5 km, although one female moved about 3.75 km between roosts. One radiotagged female shifted roost to beneath the corrugated iron of a farm-shed that supported at least 50 bats, predominantly females with young. Observations of foraging radio-tagged and lighttagged bats were frequent along a stream lined with trees, but surrounded by cleared paddocks. Foraging was observed in the air space above the creek, interspersed with occasional rapid flights across paddocks (> 500 m). We suggest that a key requirement for V. troughtoni in the rural landscape is the presence of native vegetation in close proximity to roosts, although extensive forested areas may not be required. Education of local communities about the sensitivity of these bats at cave roosts would be an important contribution to their conservation.

The seasonality of hip fracture and its relationship with weather conditions in New South Wales

2010 ◽  
Vol 19 (1) ◽  
pp. 76-80 ◽  
Author(s):  
Edith M.C. Lau ◽  
Bill G. Gillespie ◽  
Lisa Valenti ◽  
Dianne O'Connell
Keyword(s):  
Hip Fracture ◽  
New South ◽  
New South Wales ◽  
Weather Conditions ◽  
South Wales

Responses of free-ranging brownsnakes (Pseudonaja textilis : Elapidae) to encounters with humans

1999 ◽  
Vol 26 (5) ◽  
pp. 689 ◽  
Author(s):  
P. B. Whitaker ◽  
R. Shine
Keyword(s):  
Public Opinion ◽  
Air Temperature ◽  
Cloud Cover ◽  
Weather Conditions ◽  
Time Of Day ◽  
Agricultural Landscapes ◽  
Human Observer ◽  
Eastern Australia ◽  
Radio Transmitters ◽  
Free Ranging

Eastern brownsnakes (Pseudonaja textilis) are large (to 2 m), slender, dangerously venomous elapid snakes that cause significant human mortality. We recorded the responses of free-ranging brownsnakes to 455 close encounters with a human observer, using 40 snakes implanted with miniature radio-transmitters, plus encounters with non-telemetered animals. Our study area (near Leeton in south-eastern Australia) is typical of many of the agricultural landscapes occupied by P. textilis. Contrary to public opinion, the snakes were rarely aggressive. About half of the encounters resulted in the snake retreating, and on most other occasions they relied on crypsis. Snakes advanced towards the observer on only 12 occasions (<3% of encounters) during initial approach, and only three of these advances were offensive. The snakes’ responses to an approach depended on the observer’s appearance (e.g. snakes were more likely to ignore an observer wearing light rather than dark shades of clothing) and behaviour (e.g. snakes were more likely to advance if approached rapidly, and touched immediately). Snakes were more likely to retreat if they were sub-adult rather than adult, if they were warm, or if they had been moving prior to an encounter. Weather conditions (air temperature, wind velocity and cloud cover) also influenced the snakes’ responses, as did season and time of day. The snakes’ response was relatively predictable from information on these factors, enabling us to suggest ways in which people can reduce the incidence of potentially fatal encounters with brownsnakes. ‘Snakes are first cowards, next bluffers, and last of all warriors’ (Pope 1958)

Influences of weather and time of day on trap catches of bush fly,Musca vetustissima Walker (Diptera: Muscidae)

1986 ◽  
Vol 76 (3) ◽  
pp. 359-366 ◽  
Author(s):  
W. G. Vogt
Keyword(s):  
Wind Speed ◽  
Relative Humidity ◽  
Solar Radiation ◽  
New South ◽  
Time Of Day ◽  
Weather Variables ◽  
South Wales ◽  
Males And Females ◽  
Catch Rates ◽  
Trap Catches

AbstractField populations of Musca vetustissima Walker were sampled in a region of New South Wales at 2-h intervals on 35 occasions between spring 1984 and autumn 1985 using wind-oriented fly traps. Ambient temperature, solar radiation, relative humidity and wind speed explained 84·3% of the within-day deviance of total catches (both sexes combined). Temperature and solar radiation jointly explained 82·6% of this deviance (71·1 and 11·5%, respectively), indicating that the other variables, although significant, did not greatly affect trap catches. As air temperature increased, log catch rates increased non-linearly up to a maximum at 27·5°C and declined thereafter. Log catch rates increased linearly as solar radiation increased and declined linearly as relative humidity and wind speed increased. Changes in log catch rates with time of day were explained almost entirely by the four weather variables, i.e. when weather effects were removed, time of day effects were no longer significant. These weather variables also accounted for 79·9% of the between-day variation in logarithms of trap catches. Relative responses of males and females to traps differed significantly with respect to relative humidity, wind speed and time of day. Male catches tended to increase relative to female catches between 1200 h and 1800 h and also declined more slowly with increases in relative humidity and wind speed. Separate models are presented for standardization of male and female catch rates; the estimates differ from those obtained from observed sex ratios and total catch rates, but the differences are small compared to the observed day-to-day variation in catch rates.

scholarly journals Post-fire recovery of eastern bristlebirds (Dasyornis brachypterus) is context-dependent

2008 ◽  
Vol 35 (1) ◽  
pp. 44 ◽  
Author(s):  
D. W. Bain ◽  
J. R. Baker ◽  
K. O. French ◽  
R. J. Whelan
Keyword(s):  
Fire Management ◽  
New South ◽  
Large Population ◽  
Fire Intensity ◽  
Frequency Of Occurrence ◽  
South Wales ◽  
Close Proximity ◽  
Context Dependent ◽  
Burnt Areas ◽  
In Fire

In late December 2003, a wildfire in the Jervis Bay region of New South Wales burned through an area that previously supported a large population of the endangered eastern bristlebird (Dasyornis brachypterus). The eastern bristlebird has been described as fire-sensitive, and fire is implicated in the decline of the species. The frequency of occurrence of bristlebirds was investigated in the second week after the fire in a range of sites varying in fire intensity. Bristlebirds were found in burned habitats but were less common in the sites that were more intensely burnt. Bristlebirds had been surveyed along transects in this area two months before this fire and were surveyed again 1, 9 and 13 months after the fire. Compared with prefire numbers, bristlebird numbers decreased in burnt areas after the fire and increased in unburnt areas. This pattern was evident for up to nine months after the fire, after which bristlebird numbers returned towards prefire levels in both burnt and unburnt vegetation. This is in contrast to some previous research on bristlebirds and fire. We suggest that bristlebirds avoided the fire by moving to unburnt areas and returned later when conditions were more suitable. We consider that the apparently slight impact of this fire on bristlebirds was due to the close proximity of unburnt habitat and other refuges. The response of bristlebirds and presumably other birds to fire is likely to be strongly context-dependent, so fire management may be able to be designed so as to be compatible with the conservation of local bristlebird populations.

The general bioloy of Cardiaspina albitextura (Psyllidae) and its abundance in relation to weather and Parasitism.

1962 ◽  
Vol 10 (4) ◽  
pp. 537 ◽  
Author(s):  
LR Clark
Keyword(s):  
Host Plants ◽  
New South ◽  
Weather Conditions ◽  
Reproductive Rate ◽  
Southeastern Australia ◽  
South West ◽  
South Wales ◽  
Very High ◽  
Small Insect ◽  
Do So

Cardiaspina albitextura Taylor is a test-forming psyllid which inhabits the foliage of redgums, particularly Eucalyptus blakelyi Maiden, in inland southeastern Australia. In warmer areas, as on the South-West Slopes of New South Wales, this psyllid usually completes three generations per year, whereas in the cooler Southern Tablelands region it normally takes about 18 months to do so. It is a small insect with limited powers of dispersal. The majority of females oviposit within 100 yd of where they originated. The average number of eggs laid per female varies greatly even when individuals are not crowded, the observed range being 14-289. The reproductive rate appears to be influenced by weather conditions, especially by temperature. A few individuals of E. blakelyi are unfavourable to the psyllid and therefore resistant to attack. The susceptible majority exhibit considerable differences and variability in favourableness. In general, however, although there may be marked differences between individuals within stands, average favourableness does not differ greatly from place to place. When the numbers of C. albitextura become very high, i.e. when outbreaks occur, susceptible E. blakelyi suffer severe foliage damage. Where high psyllid numbers occur repeatedly at intervals of less than 3 years, they cause increasing "die back" and host plants produce progressively less new foliage. If outbreaks continue for years, trees are destroyed at an increasing rate. For the 15-20 years prior to 1950 it appears that localized outbreaks of C. albitextura were not uncommon, particularly on the Tablelands, but did not persist for long. Since then extensive outbreaks have occurred in both the Tablelands and Slopes regions. Some have persisted for 10 years and show no signs of ending. Others have lasted only for several psyllid generations. They have been more numerous and persistent in cooler areas than in the Slopes region.

Assessing the Impacts of Logging on Reptiles and Frogs in the Montane Forests of Southern New South Wales.

1996 ◽  
Vol 23 (4) ◽  
pp. 495 ◽  
Author(s):  
R Goldingay ◽  
G Daly ◽  
F Lemckert
Keyword(s):  
Management Practices ◽  
New South ◽  
New South Wales ◽  
Habitat Type ◽  
Regional Survey ◽  
Montane Forests ◽  
South Wales ◽  
Reptile Species ◽  
Frog Species ◽  
The Impact

This study describes an assessment of the medium-term effects of selection logging on the reptiles and frogs in the montane forests near Queanbeyan, New South Wales. A total of 15 reptile and two frog species was detected across 20 fixed-area plots that were selected according to broad forest type and logging history. Reptile species richness was not significantly different among the different habitat treatments. Total reptile abundance was significantly higher on logged plots, but was not influenced by forest moisture type. Individual analyses for five lizard species (accounting for 84% of all data) showed that several species (Eulamprus tympanum, E. heatwolei and Pseudemoia spenceri) had significantly greater abundances on the logged plots than on the unlogged plots, while two species (Nannoscincus maccoyi and Niveoscincus coventryi) did not differ significantly in their abundances across treatments. Thus, none of these species (which included arboreal, terrestrial and fossorial species) appeared to be adversely affected by past logging practices. Insufficient data on frogs were obtained for analysis. An additional 26 species (13 reptile and 13 frog species) were recorded during a regional survey involving 57 sites. Only two frog species were detected at more than 10 sites, illustrating the difficulty in obtaining data to determine whether logging has any impact on frog populations. Snakes are similarly difficult to assess: 13 snakes from six species were detected in this study. It is concluded that (i) the most abundant reptile species were not adversely affected by past logging, and (ii) many species of herpetofauna were patchy in their distribution across the study area, preventing resolution of the influence of habitat type or disturbance. The difficulty in collecting quantitative data on frogs and snakes confirms the importance of surveys that target endangered frog and snake species so that protective buffer zones can be delineated. Further research is required on these groups to assess the impact of forest management practices.

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