bluuebunny/crossref_metadata_2025 huggingface dataset:
Pyramidal structural defects in erbium silicide thin films
Authors: Tan Eu Jin , Bouville Mathieu , Chi Dong Zhi , Pey Kin Leong , Lee Pooi See , Srolovitz David J. , Tung Chih Hang
Published: January 2006

Pyramidal structural defects, 5–8μm wide, have been discovered in thin films of epitaxial ErSi2−x formed by annealing thin Er films on Si(001) substrates at temperatures of 500–800°C. The formation of these defects is not due to oxidation. We propose that they form as a result of the separation of the silicide film from the substrate and its buckling in order to relieve the compressive, biaxial epitaxial stresses. Silicon can then diffuse through the silicide or along the interface to fully or partially fill the void between the buckled erbium disilicide film and the substrate.
Solid-state detonation in the zinc-sulfur system
Authors: Gur’ev Dmitrii L. , Gordopolov Yury A. , Batsanov Stepan S. , Merzhanov Alexander G. , Fortov Vladimir E.
Published: January 2006

We measured the velocity of shock waves generated by the detonation of a high explosive in a stoichiometric (equimolar) mixture of Zn and S powders. The initial decrease in the velocity of the shock wave in a sample was then found to be followed by a remarkable increase in the velocity of shock wave propagation. This observation can be explained by the occurrence of the exothermic solid-state reaction Zn+S→ZnS in the zone of high dynamic pressure. The observed solid-state detonation represents a new type of transport phenomena in reactive media which may be expected to find important practical applications.
Implications of rabbit haemorrhagic disease for the short-term recovery of semi-arid woodland communities in north-west Victoria
Authors: Sandell P. R.
Published: January 2006

As part of the National RHD Monitoring and Surveillance Program, an investigation was conducted into the implications of reduced rabbit abundance (as a consequence of rabbit haemorrhagic disease, RHD) for the recovery of degraded woodlands in the Hattah area of north-west Victoria. Both structural and floristic changes were assessed within woodland communities, which are at risk after 140 years of intensive grazing. General recovery in the pasture layer was demonstrated in terms of the improved status of 'decreaser' plant response groups — palatable species. 'Increasers' (weeds) were also found to have benefited in some circumstances but not to the same extent as the decreaser groups. Evidence of structural changes was restricted to increased persistence of sucker regrowth, particularly of cattle bush (Alectryon oleifolius subsp. canescens). No evidence was found of widespread germination of woody seedlings, which is not surprising given the episodic nature of such regeneration events. The interaction of grazers was also investigated by means of a network of grazing exclosures. Less floristic benefit was associated with relatively high kangaroo densities at one location and with stock grazing at another.
Warren ripping: its impacts on European rabbits and other wildlife of central Australia amid the establishment of rabbit haemorrhagic disease
Authors: Edwards G. P. , Dobbie W. , Berman D. McK.
Published: January 2006

The impacts of warren ripping on European rabbits and other wildlife were studied at four sites in central Australia over a 2.5-year period. At each site, treated (ripped) and untreated plots were established. On the treated plots, warrens were ripped over an area of 20–140 km2. Rabbit haemorrhagic disease (RHD) became established in central Australia during the study. There were fewer rabbits on ripped plots compared with untreated plots both before and after the establishment of RHD. There was also less sign of exotic predators (red foxes and feral cats) on ripped plots. The amount of dingo sign observed and the number of peregrine falcons, brown falcons, kites and goshawks combined and kestrels and hobby falcons combined changed with time but no treatment effect was detected. No consistent treatment effect was detected for red kangaroos, varanid lizards, small mammals or other raptor species.
Epidemiology of rabbit haemorrhagic disease (RHD) in the South Island, New Zealand, 1997 - 2001
Authors: Parkes J. P. , Norbury G. L. , Heyward R. P. , Sullivan G.
Published: January 2006

Rabbit haemorrhagic disease (RHD) was illegally released in New Zealand in August 1997 and subsequently spread by farmers and naturally over all areas inhabited by rabbits. The disease has persisted, causing either annual or biennial epidemics that appear to start each spring by infecting susceptible adult rabbits and running through to the autumn infecting young rabbits of the year. Rabbit densities have been suppressed by more than 90% in many areas where numbers were initially high and epidemics returned annually, and by about 50% in areas with low initial densities and biennial epidemics, leaving between 35% and 20%, respectively, of the survivors immunised. In some areas the disease has not reduced rabbit densities and has left more than 80% (at worst) of the survivors across all age cohorts with antibodies to RHD. A possible cause of this apparent longitudinal transmission is that seropositive adult rabbits (which may retain virus) may be infectious and pass virus on to their offspring at just the right dose and age to impart immunity. A pen trial, in which we orally dosed 9-week-old rabbits born to seropositive mothers, showed that they survived and did not seroconvert, but were fully susceptible when re-dosed at about 17 weeks. We have evidence that the possible pre-existing calicivirus does not impart immunity to RHD in at least one part of New Zealand.
Statistical models for the effect of age and maternal antibodies on the development of rabbit haemorrhagic disease in Australian wild rabbits
Authors: Robinson A. J. , So P. T. M. , Müller W. J. , Cooke B. D. , Capucci L.
Published: January 2006

Statistical models have been developed to explain the influence of age and maternal antibody on the outcome of rabbit haemorrhagic disease virus (RHDV) infection of Australian wild rabbit kittens in terms of survival, survival time in those that failed to survive, and pyrexia (temperature response, or fever). Similar models describing survival and survival time were derived by substituting mass for age, owing to their high correlation. The models were developed from data obtained following the inoculation of 78 kittens 5–11 weeks old born to does with varying levels of α-RHDV immunoglobulin (IgG) antibody as measured by enzyme-linked immunosorbent assay (ELISA). A significant correlation was found between survival and doe titre but not between survival and kitten titre. It was deduced that maternal antibody in kittens can fall below the level of detection in the ELISA but still be protective. The model describing the influence of age and doe titre had the form logit(SURVIVAL) = 5.98 – 0.944(AGE) + 0.000473(DOE TITRE), and showed, for example, that kittens born to seronegative does had a 50% probability of survival at about 6 weeks old and, with a doe titre of 10 240, a 50% probability of survival at about 11 weeks old. There was a significant influence of kitten titre on pyrexia, and the model developed had the form logit(TEMPERATURE RESPONSE) = 1.436 – 0.0531(KITTEN TITRE). The influence of age and maternal antibody on survival time was fitted using Cox proportional hazard models. A parametric regression gave rise to a final model of the form S(t | AGE, DOE TITRE) = exp[–(t/ηAGE)1.7979], where ηAGE = exp[7.1838 – 0.2976(AGE) + 0.000227(DOE TITRE)]. The model showed that survival time decreased with age, but for each age category there was an increase in survival time with increasing doe titre. Kitten titre had only a marginally significant effect on seroconversion; there was no effect of kitten age or mass, or of doe titre. No kitten with a titre of 60 or more seroconverted.
Rabbit haemorrhagic disease and the biological control of wild rabbits, Oryctolagus cuniculus, in Australia and New Zealand
Authors: Cooke B. D. , Fenner F.
Published: January 2006

This review considers the history of the discovery of the rabbit haemorrhagic disease virus (RHDV) and its spread throughout the world in domestic and wild rabbits, which led eventually to its deliberate release into Australia and New Zealand for the control of a major pest, the introduced wild rabbit. The physical and genetic structure of RHDV is now well understood, and its pathogenic effects are also well known. The epidemiology of rabbit haemorrhagic disease (RHD) has been clearly documented in the field in European countries, Australia and New Zealand. Since its initial spread through largely naïve populations of wild rabbits it has established a pattern of mainly annual epizootics in most areas. The timing of epizootics is dependent on climatic variables that determine when rabbits reproduce and the appearance of new, susceptible rabbits in the population. The activity of RHDV is also influenced by climatic extremes that presumably affect its persistence and the behaviour of insect vectors, and evidence is growing that pre-existing RHDV-like viruses in some parts of Australia may interact with RHDV, reducing its effectiveness. The timing of epizootics is further modified by the resistance to RHD shown by young rabbits below 5 weeks of age and the presence of protective maternal antibodies that also protect against fatal RHD. RHD has reduced rabbit abundance, particularly in dry regions, but rabbits in cooler, high-rainfall areas have been able to maintain their populations. In Australia and New Zealand, RHD has raised the prospects for managing rabbits in low rainfall areas and brought substantial economic and environmental benefits.
Survival of brown kiwi exposed to 1080 poison used for control of brushtail possums in Northland, New Zealand
Authors: Robertson H. A. , Colbourne R. M. , Graham P. , Miller P. J. , Pierce R. J.
Published: January 2006

All 35 radio-tagged adult brown kiwi (Apteryx mantell i)
survived at least three months after being exposed to 1080 poison (sodium
monofluoroacetate) during a brushtail possum
(Trichosurus vulpecul a) control operation; 22 birds
were exposed to 1080 in pollard baits at a loading of 0.15% w/w,
and 13 birds were exposed to 1080 presented in jam baits, at a loading of
0.08% w/w. A radio-tagged juvenile was killed by a predator 2.5
months after being exposed to jam baits. In the three months after the 1080
operation, the weights of adult kiwi in the poisoned area were no different
from those in neighbouring bush patches. No traces of 1080 were found in six
eggs collected from the poisoned area. From subsequent captures of birds, all
35 birds are known to have survived at least six months after the operation,
and 33 (94%) survived one year after exposure to 1080 baits. These
results are consistent with other similar, but smaller, studies of the
survival of radio-tagged kiwi exposed to 1080 poison in pollard or carrot
baits.
We conclude that possum-control operations using green-dyed and cinnamon-lured
pollard or jam baits laced with 1080 poison pose a very low risk to brown kiwi
through accidental primary or secondary poisoning, or by starvation due to a
diminished supply of large invertebrates.
Spotlight counts for assessing abundance of rabbits (Oryctolagus cuniculus L.)
Authors: Fletcher David J. , Moller Henrik , Clapperton B. Kay
Published: January 2006

We determined the precision of spotlight counts of rabbits
(Oryctolagus cuniculus L.) and their accuracy as
estimates of density, by making counts from a motorcycle along 17 1-km
transects in the Mackenzie Basin, New Zealand. Rabbits were poisoned and
density per 1-ha quadrat was measured. Precision of spotlight counts would be
between 5–28% and 6–39%, using impracticably large
numbers of counts, even allowing for the effects of snow and heavy rain,
observer bias and number of runs per night. Spatial and unexplained variance
would result in even less precise counts using 25 transects and 1–5
nights. Actual rabbit densities explained only 41% of the variance in
spotlight counts. Confidence intervals of absolute rabbit densities are
extremely large, especially when observed counts are high. At best, spotlight
counts could be used to detect differences in actual rabbit abundance spanning
an order of magnitude or more. Observed reduction in spotlight counts is
likely to underestimate reduction in actual density because the spotlight
count index ‘saturates’ at high rabbit density. However, spotlight
counts along fixed transects before and after a control operation can be used
to estimate percentage kill with acceptable precision if the kill rate is at
least 80%.
Mechanisms of recovery after fire by rodents in the Australian environment: a review
Authors: Sutherland Elizabeth F. , Dickman Chris R.
Published: January 2006

Possible impacts and mechanisms of response by Australian rodents to fire are
identified and discussed in relation to the literature. Although there is
considerable information on patterns of population response, there is little
concerning the effect of fire on individual behaviour, mortality, or
interactions at the community level. The evidence that links observed
responses of rodents to habitat variables is largely correlative, and theories
on mechanisms of recovery are often simplified or speculative. Experimental
manipulations of resources, competitive interactions and predation rates are
proposed as the best way to clarify which factors are most influential upon
individuals, populations and communities in the post-fire environment.
The dietary ecology of Australian desert rodents
Authors: Murray B. R. , Dickman C. R. , Watts C. H. S. , Morton S. R.
Published: January 2006

Very little systematic information has been collected on the diets of
Australian rodents in arid and semiarid regions. The information that is
available is restricted generally to short periods of sampling and small
sample sizes. Here we review the diets of 15 extant and one extinct species of
Australian desert rodents, and provide new results of dietary analyses for (1)
Leggadina forresti,
Pseudomys desertorand
Rattus villosissimus from the Simpson Desert,
south-western Queensland, (2) P. albocinereus and
P. bolami from the western goldfields of Western
Australia, and (3) Notomys alexis,
P. desertor and
P. hermannsburgensis from the Tanami Desert, Northern
Territory. Overwhelmingly, omnivory is the predominant dietary strategy, with
most species (11) taking substantial amounts of invertebrate, seed and green
plant material. Of the other five species, four can be considered herbivores
and one a granivore. Of the four herbivores, however, one is extinct
(Leporillus apicalis), one is restricted to an offshore
island (Lep. conditor), while another
(P. fieldi) is classified as a herbivore from a diet
sample of four individuals only. Similarly,
P. occidentalis is classified as a granivore on the
basis of dietary sampling of two individuals alone. These findings indicate
that omnivory, over and above any other dietary strategy including granivory,
is predominant among rodents inhabiting Australian deserts.
Comparative ecology of two populations of Pseudomys australis in northern South Australia
Authors: Brandle R. , Moseby K. E.
Published: January 2006

Two disparate populations of Pseudomys australis, in the
southern and north-western Lake Eyre Basin of South Australia, were studied
over a 3-year period using trapping and radio-tracking techniques. Various
aspects of the species’ ecology were investigated. Past records of the
species were almost always associated with population irruptions following
exceptionally wet years. Aspects of population dynamics, fine-scale habitat
use, activity ranges and burrows were studied and related to habitat condition
during three dry seasons following a good season. Both areas were associated
with floodout plains in a gibber desert environment but differed in soils and
vegetation structure. The population dynamics and structure and home-range
activity also differed. These differences appeared to relate to the
availability and distribution of food and shelter in the respective locations.
The differences between populations in the two areas are discussed with
reference to the source/sink and refugia concepts.
The distribution of the New Holland mouse (Pseudomys novaehollandiae) with respect to vegetation near Anglesea, Victoria
Authors: Lock M. L. , Wilson B. A.
Published: January 2006

The distribution and abundance of the New Holland mouse
(Pseudomys novaehollandiae) was assessed at Anglesea,
Victoria, between February 1995 and October 1996. Twenty sites were trapped
within the Forest Road Flora Reserve during April and May 1995. The twenty
sites were distributed over four vegetation communities, and four successional
post-fire ages. Pseudomys novaehollandiaewas found at
only four sites, two located in heathy woodland vegetation, and two within a
regenerating pine plantation. All four sites had a post-fire age of 7-9 years.
Sites inhabited by P. novaehollandiae were found to have a high floristic
richness of heath plants, and density of the understorey vegetation was
greatest at a level below 20 cm. The population density of
P. novaehollandiae was found to be high (10-20
ha-1 ) during early 1995 but declined after June 1995 to
3-10 ha-1 . Home ranges of males and females were
similar and overlap occurred amongst individuals at the four sites, indicating
that the populations on the four grids formed a single contiguous population.
Natural histories of Australia’s stick-nest rats, genus Leporillus (Rodentia : Muridae)
Authors: Copley Peter
Published: January 2006

The former distributions of stick-nest rats
(Leporillus conditor and
L. apicalis), both extinct on the Australian mainland
since about the 1930s, were determined from literature reports, museum
records, interview responses and field surveys of key areas. Population
parameters were determined for L. conditor from early
literature accounts, studies of remnant stick-nests in caves, a three-year
study of the last known naturally-occurring populations on the Franklin
Islands, records maintained for a captive-breeding program since 1986, and
further population data obtained during systematic monitoring of reintroduced
populations. Comparable data for L. apicalis could be
obtained only from early literature accounts and remnant stick- nests in
caves; this species has not been recorded since 1933 and is presumed extinct.
Leporillus conditor is a predominantly ground-dwelling,
herbivorous rodent of semi-arid, perennial shrubland habitats, which builds
nests of interwoven sticks for protection from the elements and from
predators. Leporillus apicalis apparently occupied
similar habitats, often in sympatry with L. conditor,
but extended its range further into the arid zone and may have had a more
arboreal life-style and a more diverse diet, including invertebrates. The
demise of both species from the mainland was almost certainly due to severe
habitat degradation caused by introduced herbivores (mainly rabbits and sheep)
before, and leading into, severe drought conditions. The resulting reduction
in availability of food and cover also led to an increased vulnerability to
predation (primarily by foxes, cats, dingoes and owls).
In current L. conditor populations, females reproduce
throughout the year and have well-defined home- ranges with relatively small
core activity areas. Males have considerably larger home ranges. Predation by
owls, especially barn owls (Tyto alba) is a significant
cause of Leporillus mortalities, highlighting the
importance of cover for the rats’ survival.
Long-term dynamics of rodent populations in arid Australia: the influence of rainfall
Authors: Dickman C. R. , Mahon P. S. , Masters P. , Gibson D. F.
Published: January 2006

Populations of rodents were studied for periods of 7−9 years at each of
three sites in arid Australia. All species fluctuated dramatically in
abundance, being absent or in low numbers during droughts but erupting after
significant rainfall. Strong correlations were obtained between capture rates
and cumulative monthly rainfall residuals, with time lags, that had been
modified by an exponential decay function to model the post-rain depletion of
resources. The introduced Mus domesticus erupted within
only two months of exceptional rainfall at one site, whereas the native
rodents Notomys alexis,
Pseudomys hermannsburgensis and
P. desertor generally responded 3Œ10 months after
rain. The faster response of M. domesticus reflects its
high reproductive potential compared with the native rodents, and perhaps
greater immigration. Differences in magnitudes and delays in response to
rainfall among the native species were due probably to differences in initial
population sizes and times available for response and, for
P. desertor, to between-site differences in the quality
or quantity of food resources. Population declines in all species during dry
periods probably followed resource shortages.
Despite the usually strong linkage between rainfall and population dynamics,
rain failed to trigger population responses in rodents for prolonged periods
at two of the sites, and was not clearly associated with an eruption of
P. hermannsburgensis at the third. The lack of a
population response at one site was attributed to predation, but events at the
other two remain unexplained. We conclude that long-term studies should play
an important role in describing temporal changes in rodent populations in arid
Australia and, with field experiments, in evaluating how rainfall and other
factors combine to effect the changes.
Diets and feeding selectivities of bridled nailtail wallabies and black-striped wallabies
Authors: Evans Murray C. , Jarman Peter J.
Published: January 2006

Diets and feeding selectivities of sympatric bridled nailtail wallabies,
Onychogalea fraenata, and black- striped wallabies,
Macropus dorsalis, were studied at two sites during each
season on Taunton Scientific Reserve, Queensland. Bridled nailtail wallabies
ate a wide variety of monocotyledon and dicotyledon species (>60) in
broadly equal proportions. During dry seasons, there was a marked switch to
dicotyledons, including woody browse species, which formed over 20% of
material in faecal pellets. In contrast, black- striped wallabies were
predominantly grazers, eating a wide variety of grasses and sedges (>65
spp.). Compared with black-striped wallabies, bridled nailtail wallabies were
much more selective in their feeding, both for individual plant species and
plant parts. Bridled nailtail wallabies selected against grass species,
particularly during the dry season, and showed high selectivity for forbs in
areas where these were scarce. Black-striped wallabies generally selected
against forbs and showed random selection for grass species. Bridled nailtail
wallabies showed stronger selection for food items of relatively high
nutritional value (such as leaves and seedheads), and stronger selection
against items of relatively high fibre content (such as grass stems) than did
black-striped wallabies. Dietary overlap varied seasonally and was highest
during spring and summer. The potential for inter-specific competition was
highest during spring, when food resource abundance was lowest. The feeding
niche of bridled nailtail wallabies is narrower than that of black-striped
wallabies, indicating that the effects of competition may not be symmetric
between the wallaby species. The results of this study agree with those of
previous work on these species.
Little evidence of toxoplasmosis in a declining species, the northern quoll (Dasyurus hallucatus)
Authors: Oakwood Meri , Pritchard David
Published: January 2006

Tissues from 28 road-killed northern quolls
(Dasyurus hallucatus) were collected from Kakadu
National Park in northern Australia between 1993 and 1995. These tissues,
including brain, liver, lungs, cardiac muscle and skeletal muscle, were
examined for histological evidence of the protozoan parasite
Toxoplasma gondii. No T. gondii
cysts were found. Sufficient serum was available from 22 of these quolls to
test for antibodies to the parasite, using the latex agglutination test. Of
these, 20 showed no reaction and 2 had very low serological reactions, which
were probably not significant. This study provides little evidence that
toxoplasmosis is involved in the decline of quolls in this region.
Seasonal roosts and foraging movements of the black flying fox (Pteropus alecto) in the Northern Territory: resource tracking in a landscape mosaic
Authors: Palmer Carol , Woinarski J. C. Z.
Published: January 2006

Radio-telemetry was used to investigate roosting and movement patterns of the
black flying fox (Pteropus alecto) in the seasonal
tropics of the Northern Territory. Sixteen P. alecto
were tracked during a 12-month period to 34 roosts and were recorded at 49
foraging sites. Pteropus alecto moved roosts seasonally,
from bamboo and mangrove habitats in the dry season to rainforest in the wet
season. All radio-collared male and female P. alecto
roosted in rainforest during the major part of the wet season. Climatic
influences may be responsible for this behaviour, with rainforest perhaps
providing stable temperatures and shelter from the monsoonal rains. There was
a significant seasonal difference in the distances moved by females between
successive roosts. There was an association between roosting and foraging
habitat: P. alecto roosting in bamboo and mangroves
foraged predominantly in woodland, P. alecto roosting in
rainforest foraged in Melaleucaspp. and rainforest
habitat. Females covered greater distances from roosts to foraging locations
than did males. Distances from roosts to foraging sites were reduced for males
and females during the build- up season (September to November) and wet season
(December to April). Seasonally, foraging habitat shifted both floristically
and spatially with no significant difference between the sexes. The movements
of one female P. alecto were recorded at hourly
intervals over three consecutive nights at the beginning of the wet season.
Movement patterns were very similar between nights and over these three nights
she foraged in at least 7 distinct locations. The total distance moved per
night was 15.5–19.9 km, including return distance to the roost, assuming
straight-line movements between hourly fixes. Most foraging was done less than
6 km from the roost. The ratio of total distance moved in a night to the mean
distance of forage sites from roosts was similar between nights
(3.1–4.3), suggesting that a single roost site to forage site distance
recorded during this study can provide an index of total foraging distance.
Land tenure status identified for foraging and roosting positions recorded for
P. alecto emphasises the lack of protection for habitats
used by this species. Only 3% of foraging or roosting positions were
recorded in any type of conservation reserve.
Implications of brown tree snake captures from fences
Authors: Engeman Richard M. , Linnell Michael A. , Aguon Phillip , Manibusan Anthony , Sayama Steven , Techaira Anthony
Published: January 2006

The capture of brown tree snakes (Boiga irregularis)
from fence lines in the vicinities of air and sea ports is an important
component of the integrated approach used for curtailing the dispersal of the
species from Guam. Use of fences by brown tree snakes was characterised from
over 600 captures of snakes during spotlight searches. Two construction
designs of chain-link fences were searched, the difference being whether a
horizontal bar or a steel cable was used to support the chain link on top.
Both fence designs had snakes concentrated at the fence tops – fences
having top bars produced 92% of captures on the top third of the chain
link, the top bar, or the parallel barbed-wire strands above the fence; fences
without top bars produced 82% of captures from the top third of the
chain link or the wires above it. Most snakes were found in a horizontal
position and no general trends were found through the night for when snakes
ascend or descend the fences. To help concentrate snakes at the tops of fences
for facilitating control efforts, we recommend the use of a horizontal bar to
support the chain link on top, as well as the use of parallel barbed- wire
strands above the fence. We discuss management implications for using searches
of fences to control brown tree snakes and to detect new brown tree snake
populations in other locales.
The foraging zones of breeding royal (Eudyptes schlegeli) and rockhopper (E. chrysocome) penguins: an assessment of techniques and species comparison
Authors: Hull Cindy L.
Published: January 2006

This study used VHF telemetry, time–depth recorders (TDRs) collecting
geolocation and sea-surface temperature data, and foraging-trip durations to
describe and compare the foraging zones of royal and rockhopper penguins at
Macquarie Island. VHF telemetry was unsuccessful, but TDRs were deployed 61
times across the four stages of the breeding season (males during incubation,
females during incubation, guard stage and creche stage) during the
1994/95 and 1995/96 austral summers, with 37 providing data for
analysis. The errors inherent in geolocation made it impossible to determine
precise foraging zones and overlaps between the species. However, sea-surface
temperature data and foraging-trip durations provided estimates of foraging
zones. Both species foraged in waters of the same temperature
(6.8–10.8°C), representing the same regions of the polar frontal
zone. It was estimated that rockhopper penguins did not travel as far as royal
penguins, providing some degree of segregation in foraging zones. When the
data were assessed contemporaneously, to take into account the 3-week
asynchrony in the breeding season of the species, the overlap in foraging
zones was small.
Home-range characteristics of an alpine lizard, Niveoscincus microlepidotus (Scincidae), on Mt Wellington, southern Tasmania
Authors: Melville Jane , Swain Roy
Published: January 2006

We studied the home ranges of the alpine skink,
Niveoscincus microlepidotus, in an alpine transition
zone on Mt Wellington, Tasmania, over a 5-month period to examine seasonal
patterns in the home-range characteristics of four male, four female and two
sub-adult juvenile lizards. Home-range sizes and activity patterns within
these were quantified. Adult males had significantly larger home ranges with
more activity centres than adult females; most activity centres were clearly
synonymous with basking sites and were defended by overt aggressive behaviour.
Home ranges of males showed little overlap and no seasonal variation while
those of femals were unusual amongst reptiles in showing extensive overlap and
seasonal change in size. Ranges were smallest in spring when all females were
pregnant and were smallest in summer when only one female was pregnant. Range
overlap ensured that all females studied had potential access to at least two
males. Juveniles had no defined home ranges and appeared to be transients.
Caching of baits by foxes (Vulpes vulpes) on agricultural lands
Authors: Kay Barry , Saunders Glen , McLeod Lynette
Published: January 2006

Baiting is widely used to control the introduced fox
(Vulpes vulpes) in Australia. Caching of baits by foxes
was observed through the use of miniature radio-transmitters. Both non-toxic
and toxic (1080) baits were used to determine the number of baits cached, the
location of these caches with respect to original placement and the extent to
which these caches are later retrieved and consumed. These trials established
that foxes cache 1080 baits. An average of 34% of transmitter baits
offered were taken and 10% were cached. The mean distance from the bait
station to the cache was 156 m, with some baits being cached up to 800 m away.
Implications of these results for current fox management strategies and the
consequences of using bait take as a population index are discussed.
Brushtail possum, Trichosurus vulpecula, populations in south-western Australia: demography, diet and conservation status
Authors: How R. A. , Hillcox S. J.
Published: January 2006

The common brushtail possum, Trichosurus vulpecula, has
suffered a marked reduction in its geographic range from the arid areas of
Western Australia and now is abundant only in the more mesic forests and
woodlands of the south-west. A mark–recapture and dietary study of a
population in the tuart/peppermint forests near Busselton found that the
species occurred at a density of 2–3 individuals per hectare, fed
principally on peppermint, Agonis flexuosa, but occurred
in all treed habitats in the area, including
Pinus radiata plantations. Females matured in their
third year and produced a single young annually between April and September
that was weaned about seven months later. Comparisons between the demographic
parameters of this population and that of a study from semiarid south-western
Australia showed marked differences, which were comparable to variation shown
by population studies of T. vulpecula in eastern
Australia and New Zealand. Predation and habitat alteration have probably had
a marked effect on determining the present distribution and abundance of the
species in south-western Australia.
Trapping efficiency for foxes (Vulpes vulpes) in central New SouthWales: age and sex biases and the effects of reduced fox abundance
Authors: Kay Barry , Gifford Edward , Perry Rob , van de Ven Remy
Published: January 2006

A total of 276 red foxes (Vulpes vulpes) was captured
over 40 597 trap-nights during 1994–96 at three separate sites in
central New South Wales, resulting in an overall trapping efficiency of one
fox per 147 trap-nights. Trapping using multiple trap sets placed at carcases
was 3.2 times more efficient than trapping using single trap sets. During
1994–95, when two of the sites suffered a severe drought, fox abundance
declined to less than 0.2 foxes km–1 of spotlight
transect; trapping efficiency at those sites also declined, to an average of
one fox per 315 trap-nights. Mean trapping efficiency for non-drought periods
was one fox per 135 trap-nights, 2.3 times more efficient than during the
drought period. In 1995 and 1996, 353 foxes were shot in areas adjacent to
each site. This gave the opportunity to compare sex and age biases between the
trapped and shot samples: the ratio of males to females was significantly
higher in the trapped sample than in the shot sample, and there was also a
significantly higher ratio of adults to juveniles in the trapped sample than
in the shot sample.
Monitoring coyote population changes with a passive activity index
Authors: Engeman Richard M. , Pipas Michael J. , Gruver Kenneth S. , Allen Lee
Published: January 2006

A passive tracking index method that has been successfully applied to dingoes
(Canis lupus dingo) in Australia was shown to have more
general applicability to wild canids by monitoring coyote
(Canis latrans) populations in southern Texas. The index
was calculated simultaneously for multiple species of animals from
observations on the number of intrusions onto a series of tracking plots over
several days. We found that the index reflected changes in coyote activity
before and after a trapping program on each of 2 ranches. We also were able to
simultaneously monitor bobcat (Felis rufus) and
white-tailed deer (Odocoileus virginianus) populations,
producing some interesting (and unexpected) insights. In our study area, we
found it difficult to distinguish the number of rabbit and rodent intrusions
into the plots, but these animals might be indexed in other habitats. Analyses
of the data as binary responses (presence or absence of spoor on each tracking
plot), as has been done in scent-post surveys, reduced the sensitivity and
accuracy of inferences.
Introduction of the rabbit flea, Spilopsyllus cuniculi (Dale), to a subantarctic island (Kerguelen Archipelago) and its assessment as a vector of myxomatosis
Authors: Chekchak T. , Chapuis J.-L. , Pisanu B. , Boussès P.
Published: January 2006

Introductions of the rabbit flea, Spilopsyllus cuniculi
(Dale), were made on an island (3.1 km2) of the
Kerguelen subantarctic archipelago in January and December 1987. Despite a
small founding population, the species succeeded in establishing itself. Three
years after introduction, the rate of spread was 614 ± 133 m (between
1990 and 1993). Despite the subantarctic climate of Kerguelen, the burdens
were similar to those noted in habitats favourable to this ectoparasite. The
flea burden of adult rabbits after colonisation of the whole island was higher
for pregnant females (182 ± 21, n = 98)
than for non-pregnant ones (85 ± 16, n =
68) or males (20 ± 3, n = 116). The
circulation of myxoma virus, present on this island for several decades, has
been favoured by the flea. As a result, the proportion of rabbits with
antibodies rose from 34% before introduction of the flea to 85%
in 1998. Moreover, the introduction of fleas has changed the relative
proportions of both adult males and females with antibodies. Those proportions
were not different before the introduction but more males than females showed
antibodies when the flea colonised the whole island. Finally, the prospects of
the introduction of Spilopsyllus cuniculi on the main
island of the archipelago are discussed.
The uptake of dried meat baits by foxes and investigations of baiting rates in Western Australia
Authors: Thomson P. C. , Algar D.
Published: January 2006

The uptake of dried meat baits by foxes (Vulpes vulpes)
was measured in large-scale field trials using non-toxic baits containing the
biomarker tetracycline. Baits were aerially delivered at nominal baiting rates
of 5 baits km–2 (4 sites) and 10 baits
km–2 (3 sites). The proportion of sampled adult
foxes that had consumed the bio-marked baits ranged from 62 to 88%
(mean 79.5%). Uptake of baits did not increase at the higher baiting
rate. Bait uptake at the levels recorded in these trials would result in
effective reductions in fox populations exposed to toxic baits. Bait uptake
would have been sufficient to prevent the spread of rabies within fox
populations at the densities occurring during the study, either by population
reduction or in conjunction with oral vaccination.
Demographic characteristics and social organisation of a population of red foxes in a rangeland area in Western Australia
Authors: Marlow N. J. , Thomson P. C. , Algar D. , Rose K. , Kok N. E. , Sinagra J. A.
Published: January 2006

Intensive destructive sampling of a population of red foxes
(Vulpes vulpes) was undertaken over an area of 200
km2. A total of 204 foxes, estimated to be 94% of
the total population on the site, was collected. Population density was
0.46–0.52 adult foxes km–2. Sampling was
carried out in December, when young of the year were present and when data on
female productivity could be obtained from counts of placental scars.
Life-table analysis for vixens revealed that mortality was greatest for those
aged 0–16 months and those older than 3 years. Average mortality of
adult vixens was 39%. Adult vixens (n =
47) had an average (s.e.) of 3.7 0.3 placental scars; 8.5% of vixens
failed to breed. The number of placental scars did not vary significantly with
age. Various hypothetical scenarios were used to identify which social
system(s) may have been operating in the area. Predictions of vixen
productivity and cub mortality were compared with observed reproductive data
and the actual number of cubs collected. The scenario that best matched the
observations was a simple mated pair system. Pure dominance hierarchies were
unlikely to have occurred. The implications of the findings are discussed in
relation to the ability of foxes to overcome natural or artificially-imposed
population reduction. It was estimated that under a fertility control regime,
>45% of vixens would need to be sterilised before the fox population
would begin to decline.
The longevity and efficacy of 1080 meat baits used for dingo control in central Australia
Authors: Twigg Laurie E. , Eldridge Steve R. , Edwards Glenn P. , Shakeshaft Bernie J. , dePreu Nicki D. , Adams Neville
Published: January 2006

In central Australia, most 1080 (sodium monofluoroacetate) meat baits placed
on soil in predator-proof cages remained toxic to dingoes, foxes and feral
cats for at least 8 months regardless of whether they were protected from rain
or not. Thus, untaken baits will remain a potential hazard to non-target
species, particularly farm dogs, for a considerable period. However, when
dingo-control programs were monitored (n = 3
stations), approximately 85% of meat baits were taken within 4 days.
Dingo-control programs were undertaken on three stations by placing 1080 meat
baits near water points (bores) with known dingo activity. Baiting was
effective on two stations but not on the third. Where successful, dingo
numbers were reduced by 50–70%. The failure on the third station
was not due to the lack of bait-take as approximately 80% of these
baits were taken within 4 days; it was probably caused by the presence of
ephemeral water-bodies that could not be baited. However, this technique was
effective in removing those dingoes that utilised the artificial water points,
and hence were likely to be interacting with cattle. Such an outcome has
benefits to both conservation and the pastoral industry, as problem dogs are
removed without placing the long-term survival of dingoes at risk.
Distribution of the southern brown bandicoot (Isoodon obesulus) in the Portland region of south-western Victoria
Authors: Rees Michael , Paull David
Published: January 2006

The southern brown bandicoot (Isoodon obesulus) occurs
across the periphery of southern and eastern Australia as a series of isolated
regional populations. Historical records and recent surveys conducted for
I. obesulus indicate that it has disappeared or
decreased significantly from many parts of its former range. Vegetation
clearance, habitat fragmentation, feral predators and fire have all been
implicated in the decline of the species.
This paper examines the distribution of I. obesulus in
the Portland region of south-western Victoria. Historical records of
I. obesulus were compiled from the specimen collection
of Museum Victoria, the Atlas of Victorian Wildlife, Portland Field
Naturalists’ Club records and anecdotal sources. Field surveys were
conducted to determine the current distribution of
I. obesulus in the study area based on evidence of its
foraging activity.
The historical records reveal limited information: most are clustered around
centres of human activity, indicating observational bias. The field surveys
demonstrate that I. obesulus occurs in the Portland
region as a series of local populations. Each local population is associated
with a patch of remnant native vegetation separated from neighbouring patches
by dispersal barriers. Within these habitat remnants the occurrence of the
species is sporadic. Approximately 69% of the potential habitat is
managed by the Forests Service, 31% is managed by Parks Victoria, and
less than 0.5% is held under other tenures. Spatial isolation of
habitat remnants, fires and feral predators are the main threats to
I. obesulus in the Portland region.
Mortality factors acting on adult rabbits in central-western New South Wales
Authors: Moriarty Andrew , Saunders Glen , Richardson Barry J.
Published: January 2006

Mortality of radio-tagged adult rabbits
(Oryctolagus cuniculus) (n
= 274) was monitored for one year in central-western New South Wales.
The overall mortality rate was 82%. Predation was the most important
and consistent cause of adult rabbit mortality, accounting for 44% of
the total number of rabbits, followed by Rabbit Haemorrhagic Disease (RHD)
(16%), myxomatosis (9%), unknown causes (9%), and
enteritis/peritonitis (2%). Foxes were the most important
predators, accounting for 28% of radio-tagged rabbits. Medium to large
birds of prey were less important, accounting for 10%, followed by
cats, which were responsible for 6% of the deaths of radio-collared
rabbits. Myxomatosis outbreaks occurred in February/March and
November–January. An RHD outbreak occurred during July, with 40%
of the adult rabbit population being killed. The number of male and female
radio-collared adult rabbits killed by each mortality agent throughout the
year was similar. The proportions of warren-dwelling rabbits and
surface-dwelling, solitary rabbits killed were similar overall; however, a
significantly higher number of warren-dwelling rabbits were killed by
myxomatosis and a significantly higher number of surface-dwelling rabbits were
killed by RHD.
Variation in call properties of the snow petrel, Pagodroma nivea, in relation to sex and body size
Authors: Barbraud Christophe , Mariani André , Jouventin Pierre
Published: January 2006

We studied the physical parameters of calls of the snow petrel,
Pagodroma nivea, in relation to body size, sex and
individual specificity. Frequency parameters were related to body size in both
males and females; larger individuals’ voices were pitched ≈2 kHz
lower than those of smaller individuals. Males’ voices were pitched, on
average, 376 Hz lower than those of females but the relation between frequency
parameters and body size was similar in males and females. The rhythm of the
call was sex-specific, the intersyllabic duration being shorter in females
than in males. The variables most specific to individuals were those relating
to frequency parameters, duration of the call and temporal patterning. The
relationship between body size and frequency parameters, together with the
high degree of geographic variation found in this species, suggest that care
should be taken when analysing geographic variation in bird calls.
Foraging behaviour in orb-web spiders (Araneidae): do web decorations increase prey capture success in Argiope keyserlingi Karsch, 1878?
Authors: Herberstein M. E.
Published: January 2006

Orb web spiders in the genus Argiope attach highly
visible silk bands called decorations or stabilimenta to their webs. Two
different hypotheses regarding the function of these structures were
investigated in the field using Argiope keyserlingi:
prey attraction and anti-predatory device. The first hypothesis suggests that
web decorations attract prey to the web, and webs carrying decorations will
capture more prey than those without. A field census of prey capture showed
that webs adorned with more decorative bands indeed captured more but
similarly sized prey per hour compared with webs carrying fewer decorations.
Web height or web size, however, were not related to the rate of prey capture.
This pattern was confirmed by a paired comparison of prey-capture rates within
individuals that increased or decreased the number of decorative bands on
consecutive days. Individuals that used more decorations also captured more
prey compared with days when they spun fewer decorations. The second
hypothesis suggests that these structures function as anti-predatory devices
and, consequently, spiders on decorated webs benefit from a lower rate of
mortality than spiders on undecorated webs. A census of the mortality rates of
spiders over 19 days revealed that spiders did not disappear from undecorated
webs more frequently than from decorated webs. Consequently, the idea that web
decorations act as anti-predatory devices in
A. keyserlingi was not supported.
The annual reproductive cycle and sperm storage in the bearded dragon, Pogona barbata
Authors: Amey Andrew P. , Whittier Joan M.
Published: January 2006

Pogona barbata, a large lizard that inhabits the open
woodlands of eastern Australia, has been reported to have a high annual
reproductive output, which is contrary to expectations for a large lizard. To
better understand this anomaly, its reproductive cycle and morphology were
investigated. Males were spermatogenic year round, with only a brief period of
regression in January (late summer). Females were vitellogenic and gravid
through August–December (spring to early summer). Two or three large
clutches (14–26 eggs per clutch) were produced each breeding period.
Females had two germinal beds in each ovary, and all four actively produced
eggs simultaneously. Clutches overlapped such that the next clutch began
vitellogenesis before the first was laid. These characteristics make this
species’ reproductive output one of the largest known among lizards.
Reproductive females had sperm stored in oviductal crypts, but there was no
evidence of sperm storage outside the breeding period. The short-term storage
of sperm by breeding females may promote sperm competition between males.