bluuebunny/crossref_metadata_2025 huggingface dataset:
An evaluation of feral pig trapping
Authors: Choquenot D , Kilgour RJ , Lukins BS
Published: June 2005

The size of feral pig populations that survive conventional (food bait) trapping campaigns on two sites,
and the tendency of trapping to preferentially remove sows, were examined. The use of traps containing
oestrus-induced sows to enhance the trapping response obtained with conventionally baited traps was
also investigated. Estimates of percentage reduction achieved by conventional trapping on the two sites
were derived from two indices, proportional bait take and spotlight counts, using index-manipulationindex
measures of pig abundance. Proportional bait take indicated reductions in pig abundance of 100%
in 16 nights and 93% in 14 nights for the two sites from conventional trapping, while spotlight counts
estimated reductions of 81% and 83%, respectively. Sex ratios of pigs on both sites were at parity prior
to trapping, but strongly biased in favour of males after trapping. There was a coincident female bias
in the sex ratio of trapped pigs. Subsequent to conventional trapping, no pigs were trapped using
oestrous sows as bait, indicating that the use of oestrous sows does not enhance the trapping response
achieved using conventional techniques. Trapping data are used to derive a compartmental model of
the trapping programme. The model is used to identify potential strategies for improving the efficacy
of feral pig trapping programmes.
Distribution and abundance of herons, egrets, ibises and spoonbills in the Alligator Rivers Region, Northern Territory
Authors: Morton SR , Brennan KG , Armstrong MD
Published: June 2005

Aerial surveys between 1981 and 1984 were used to identify monthly trends in the abundance of Pacific
herons (Ardea pacifica), pied herons (Ardea picata), cattle egrets (Ardeola ibis), great egrets (Egretta
alba), little egrets (Egretta garzetta), intermediate egrets (Egretta intermedia), glossy ibis (Plegadis
falcinellus), sacred ibis (Threskiornis aethiopica), straw-necked ibis (Threskiornis spinicollis) and royal
spoonbills (Platalea regia) on five floodplains of the Alligator Rivers region, 250 km east of Darwin
in the monsoonal Northern Territory. Ground surveys were conducted during the same period on one
of the floodplains, the Magela. The aerial surveys indicated that the Magela floodplain was inhabited
by few of these birds during the wet season (November-March), but that numbers then increased
substantially in the dry season. The Nourlangie floodplain and Boggy Plain (a large backswamp of the
South Alligator floodplain) showed similar patterns, but the numbers of birds tended to be lower.
Birds were generally uncommon on the shallower East Alligator and Cooper floodplains, except for
egrets in the wet season. Ground surveys suggested that the birds sought out the persistent swamps that
characterise the Magela foodplain in the dry season. Ground surveys also indicated that aerial surveys
underestimated densities. On the basis of correction factors calculated from ground surveys, peak
numbers on the five floodplains were roughly estimated to be about 4000 pacific herons, 50 000 pied
herons, 300 000 egrets (primarily intermediate egrets), 60 000 glossy ibis, 16 000 sacred ibis, 80 000
straw-necked ibis and 35 000 royal spoonbills. Great-billed herons (Ardea sumatrana), white-faced
herons (Ardea novaehollandiae), striated herons (Butorides striata), rufous night herons (Nycticorax
caledonicus), black bitterns (Dupetor flavicollis) and yellow-billed spoonbills (Platalea flavipes) were
recorded sporadically in low numbers. The Alligator Rivers region acted as a dry-season refuge for
herons, egrets, ibises and spoonbills because of the unusually persistent fresh waters of the Magela
and Nourlangie floodplains and some of the backswamps of the South Alligator, such as Boggy Plain.
Wetland characteristics and waterbird use of wetlands in south-western Australia
Authors: Halse SA , Williams MR , Jaensch RP , Lane JAK
Published: June 2005

The presence or absence of 61 waterbird species on 95 wetlands in south-western Australia was
related to six wetland characteristics: salinity, emergent vegetation, water depth, pH, phosphorus level
and wetland size. More species were associated with salinity and vegetation than with other wetland
characteristics. There were more positive associations with brackish than with fresh or saline wetlands
and few species occurred in hypersaline wetlands. Trees or shrubs and sedges were the vegetation
with which most species were associated; few species were recorded on completely open wetlands or
those with only samphire.
The 95 wetlands were classified into five groups on the basis of waterbird use. All wetland
characteristics differed between groups but larger differences occurred in salinity, vegetation and water
depth. The wetland group that supported most species also supported the highest numbers of waterbirds
and most breeding species.
Problem crocodiles, Crocodylus porosus, at Nhulunbuy, Northern Territory: an assessment of relocation as a mangaement strategy
Authors: Walsh B , Whitehead PJ
Published: June 2005

Since 1986 the Conservation Commission of the Northern Territory has operated a programme to
remove 'problem' saltwater crocodiles from waters in and adjoining the township of Nhulunbuy.
Over a period of five years, 52 different saltwater crocodiles (44 male) were captured. Most (48) were
released at remote sites designated by the traditional Aboriginal owners of the surrounding lands.
Release distances from the township varied from 17 to 282 km (by coastline). Many crocodiles (47.9%),
including those released at the most distant sites, returned to, and were subsequently recaptured at, the
township. Total capture rates (initial captures and recaptures pooled) varied seasonally, with fewer
crocodiles being caught in the cooler dry season. During the wet season capture rates remained high,
but relatively fewer 'new' crocodiles were caught. Probability of recapture could not be related to
distance and direction of release from the township, nor size and sex of the released crocodile.
Frequency of capture of individual crocodiles (1-8 times) was also unrelated to these variables. The
high rates of return indicate that relocation is unlikely to be an effective strategy for managing humancrocodile
interactions, at least in areas where potential release sites already support saltwater crocodile
populations near carrying capacity.
A Comparison of Three Ageing Techniques for Feral Pigs From Subalpine and Semi-Arid Habitats.
Authors: Choquenot D , Saunders G
Published: June 2005

Three ageing techniques were tested on samples of wild-caught feral pigs from subalpine (n =35) and
semi-arid (n =64) areas in eastern Australia, and on a sample of known-age captive feral pigs reared
from stock from semi-arid areas (n =15). Techniques employed were based on morphometric relationships,
patterns of tooth eruption and wear, and counts of cementum lines in permanent incisors.
Cyclic seasonal conditions led to apparently annular cementum line deposition for pigs from the
subalpine area. In contrast, stochastic variation in seasonal conditions led to irregular cementum line
deposition in pigs from the semi-arid area and captive-reared pigs of semi-arid stock. On the assumption
that cementum lines are annular in pigs from the subalpine site, patterns of tooth eruption and
wear and morphometrics returned reasonably accurate age estimates, the former being more precise.
Patterns of tooth eruption and wear returned reasonably accurate age estimates for known-age captivereared
pigs, whereas morphometrics gave increasing underestimates of age for progressively older pigs.
On the assumption that patterns of tooth eruption and wear return similarly accurate age estimates for
wild pigs from the semi-arid area, morphometrics again underestimated true age. A correction to the
morphometric technique to improve its accuracy for semi-arid areas is given.
The Acute Toxicity of Cholecalciferol to the European Rabbit, Oryctolagus Cuniculus.
Authors: Eason CT
Published: June 2005

The toxicity of cholecalciferol in the rabbit was evaluated as part of an assessment of alternative
toxins to sodium monofluoroacetate (1080) and pindone for large-scale rabbit control in the South
Island of New Zealand. After a dose-ranging study spanning the known LD50 values for other mammals
(up to 400 mg kg-1) an acute toxicity study established an LD50 of 9mg kg-1 and LD95 of 18mg
kg-1 for the rabbit, which proved very susceptible to cholecalciferol.
Patterns of shorebird abundance in eastern Moreton Bay, Queensland
Authors: Thompson JJ
Published: June 2005

An indirect census method was developed to enable the first large-scale censuses of shorebirds in eastern
Moreton Bay, Queensland. The method used the number of bar-tailed godwits counted on high-tide
roosts, and the proportion of species on associated intertidal feeding areas, to estimate the abundance
of all species. Shorebirds tended to be more abundant at the time of the northward migration, while
fluctuations in numbers suggested that shorebirds staged in eastern Moreton Bay during both the
southward and northward migrations. Census results highlighted the large number of grey-tailed tattlers,
eastern curlews and bar-tailed godwits using eastern Moreton Bay, and provided further evidence that
Moreton Bay is a site of international significance for shorebirds.
Distribution and abundance of grebes, pelicans, darters, cormorants, rails and terns in the Alligator Rivers Region, Northern Territory
Authors: Morton SR , Brennan KG , Armstrong MD
Published: June 2005

Aerial surveys between 1981 and 1984 were used to identify monthly trends in the abundance of
Australian pelicans (Pelecanus conspicillatus), darters (Anhinga melanogaster), little pied cormorants
(Phalacrocorax melanoleucos), and whiskered terns (Chlidonias hybrida) on five floodplains of the
Alligator Rivers region, 250 km east of Darwin in the monsoonal Northern Territory. Ground surveys
were conducted during the same period on one of the floodplains, the Magela plain. The aerial surveys
indicated that the Magela floodplain was inhabited by few of these birds during the wet season
(November-March), but that numbers then increased substantially in the dry season. The Nourlangie
floodplain showed similar patterns, but the numbers of birds tended to be lower. Birds were generally
uncommon on the shallower East Alligator and Cooper floodplains. Ground surveys suggested that
the birds sought out the persistent swamps that characterise the Magela floodplain in the dry season.
Ground surveys also indicated that aerial surveys underestimated densities; on the basis of correction
factors calculated from ground surveys, peak numbers on the five floodplains were roughly estimated
to be about 2000 darters, 9000 little pied cormorants, 55 000 Australian pelicans and 50 000 whiskered
terns. Little black cormorants (Phalacrocorax sulcirostrus) were sometimes abundant, but their sporadic
occurrence prevented analysis of seasonal trends. Australasian grebes (Tachybaptus novaehollandiae),
great cormorants (Phalacrocorax carbo), pied cormorants (Phalacrocorax varius), buff-banded rails
(Rallus philippensis), Baillon's crakes (Porzana pusilla), white-browed crakes (Poliolimnas cinereus),
purple swamphens (Porphyrio porphyrio), Eurasian coots (Fulica atra), silver gulls (Larus novaehollandiae),
white-winged terns (Chlidonias leucoptera), gull-billed terns (Gelochelidon nilotica) and
Caspian terns (Hydroprogne caspia) were recorded in low numbers. The Alligator Rivers region acted
as an important dry season refuge because of the unusually persistent fresh waters of the Magela and
Nourlangie floodplains and some of the backswamps of the South Alligator, such as Boggy Plain.
The common wolf snake, Lycodon aulicus capucinus, a recent colonists of Christmas Island in the Indian Ocean
Authors: Fritts TH
Published: June 2005

The discovery of the common wolf snake, Lycodon aulicus capucinus, on Christmas I . in the Indian
Ocean suggests that individuals of the species have colonised the island recently. On the basis of
biological information for this widespread colubrid snake and for the brown tree snake, Boiga
irregularis, a well-documented pest species on Guam, the establishment of the common wolf snake
would pose a severe threat to the native fauna and ecology of Christmas I. Immediate research is
needed to document the spread of the snake, to evaluate its effects on other fauna, and to control or
eradicate the species before it becomes firmly established.
Microhabitat use by the long-nosed potoroo, Potorous tridactylus, and other small mammals in remnant forest vegetation, south-western Victoria
Authors: Bennett AF
Published: June 2005

Microhabitat use by the long-nosed potoroo, Potorous tridactylus, and six other species of small
mammal was studied in remnant forest vegetation in south-western Victoria, Australia. Throughout
its geographic range, P. tridactylus is consistently associated with dense vegetation in the ground and
shrub strata. However, at a local scale, captures of P. tridactylus were not clearly associated with a
particular floristic group, and were not strongly correlated with any structural feature of the vegetation.
Rather, individuals utilised a range of sites of differing floristic composition and vegetation density.
Dense cover provided diurnal shelter and protection from predators, whereas food resources were most
abundant in adjacent more open areas. The use of vegetation mosaics or ecotones that allow the
inclusion of contrasting microhabitats within an individual home range appears to be characteristic
of potoroids in temperate environments. Such mosaics may result from topographic or edaphic
variation, or from sera1 successional stages in vegetation following disturbance. Of the other small
mammals, the bush rat, Rattus fuscipes, and the brown antechinus, Antechinus stuartii, favoured
floristic groups that provided dense low cover. Captures of the swamp rat, Rattus lutreolus, were
clumped, and centred on several sites along the forest edge on impeded drainage where potential foods
were common. The long-nosed bandicoot, Perameles nasuta, and the southern brown bandicoot, Isoodon obesulus, were uncommon and clear microhabitat preferences were not displayed. The house
mouse, Mus musculus, was of transient occurrence, mostly during autumn, and no obvious habitat
preference was apparent. The quality and availability of microhabitats in remnant vegetation, together
with landscape structure, are important in ensuring the persistence and conservation of small mammals
in fragmented landscapes.
Predicted susceptability of Dasyurus geoffroii to canid baiting programmes: variation due to sex, season and bait type
Authors: Soderquist TR , Serena M
Published: June 2005

A laboratory assessment of the susceptibility of Dasyurus geoffroii to baits used to control foxes and
dingoes was conducted using five types of non-poisoned baits: polony, fresh meat, meat dried by 50%
and 70% of the original weight, and compressed beef crackle. Trials were designed to simulate the
initial encounter of a bait by hungry wild juveniles and adults of both sexes, including lactating females.
In overnight trials, juveniles and lactating females ate significantly more fresh meat per body weight
(mean consumption: 23.7% for juvenile males, 21.5% for juvenile females, 23.1% for lactating
females) than non-lactating adult females and adult males (combined mean, 18.3%). Maximum
overnight bait consumption was 43% of body weight. These values greatly exceed those previously
reported for other species of Dasyurus. Moist baits were eaten more rapidly and in larger amounts than
drier baits. Seasonal factors lead to the prediction that the period when canid baiting can be conducted
with the least danger to Dasyurus geoffroii is January-March.
Hypogeal fungi in the diet of the long-nosed potoroo (Potorous tridactylus) in mixed-species and regrowth eucalypt forest stands in south-eastern Australia
Authors: Claridge AW , Tanton MT , Cunningham RB
Published: June 2005

The diet of the long-nosed potoroo (Potorous tridactylus), a medium-sized ground-dwelling marsupial,
was monitored (using faecal analysis) in a multiaged eucalypt forest site, and a regrowth eucalypt forest
site in south-eastern Australia. In the multiaged forest P. tridactylus was primarily mycophagous,
consuming the sporocarps (fruiting bodies) of at least 58 fungal species. Most of these taxa were
hypogeal (underground fruiting) basidiomycetes thought to form mycorrhizae on the roots of a variety
of plants. The percentage occurrence of fungus in faeces decreased in spring and summer and increased
in autumn and winter. This pattern was opposite to the changing occurrence in faeces of other food
types, and the percentage occurrence of spores of a major fungus species. At the regrowth forest site
the quantity of fungus in faeces of P. tridactylus was lower but more constant over time. There were
also differences in the percentage occurrence of spores of at least two fungal species. Additionally,
the diversity of fungal taxa found as spores in faeces at the regrowth site was significantly lower (on
average) than that recorded in faeces from the multiaged site. Differences in the fungal diets of the
two P. tridactylus populations may be partially attributable to the disturbance (fire and logging) histories
of each site.
Anticoagulant Effects of Pindone in the Rabbit and Australian Bushtail Possum.
Authors: Eason CT , Jolly SE
Published: June 2005

The anticoagulant and toxic effect of the rodenticide pindone were compared in the rabbit and the
Australian brushtail possum (Trichosurus vulpecula). Six possums and six rabbits were dosed orally
with 25mg kg-1 pindone, and another five possums were dosed with 100mg kg-1 pindone. Blood
samples were taken before dosing and 6 days after dosing. In rabbits, the mean haematocrit was
reduced from 0.41 to 0.14, the one-stage prothrombin time increased from 7.1 to more than 120 s,
and activated partial prothrombin time increased from 26.1 to more than 180 s. These parameters
were unchanged in the possums that received 25mg kg-1. In possums that received 100mg kg-1 the
one-stage prothrombin time increased from 41.9 to 80.0 s and the activated partial prothrombin time
increased from 30.2 to 103.9 s. The haematocrit was unchanged. Half the rabbits died with extensive
haemorrhaging within 6 days, but there was no haemorrhaging or mortality in the possums in either
dose group.
Home-range estimates and habitat of the yellow-bellied glider (Petaurus australis) at Waratah Creek, New South Wales
Authors: Goldingay RL , Kavanagh RP
Published: June 2005

The yellow-bellied glider (Petaurus australis), the largest of the exudivorous marsupials, lives in small
family groupings and occupies virtually exclusive home ranges. A variety of estimation techniques were
used to determine the home-range area of five glider groups. Two sets of data were analysed for each
glider group; one included the locations of all observations while the other utilised a subset considered
to represent independent observations based on a 3-h interval between consecutive locations. The
techniques favoured for estimating home-range area, minimum convex polygon (MCP) and 95% isopleth
of the harmonic mean (95% HM), gave mean values of 59 ha and 46 ha, respectively, when all data
were included. These values were 28% and 14% larger, respectively, than those estimated with
independent data. An extrapolation that accounted for the influence of the number of locations on
the area estimated gave a mean MCP value of 63 ha for the five groups. This value was compared with
estimates for other exudivorous mammals and is much greater than that predicted from the body weight
of this species. The home ranges (defined by the 95% HM) of the five glider groups included different
proportions of the seven forest types available in the study area. The forest type in which Eucalyptus
ovata predominated was identified as a key habitat. It was the least abundant yet was included in all
five home ranges, unlike several of the more abundant forest types which were absent from some home
ranges. The above results are discussed in relation to forest management and conservation.
Roosting and foraging ecology of the Queensland blossom bat (Syconycteris australis) in north-eastern New South Wales: flexibility in response to seasonal variation
Authors: Law BS
Published: June 2005

Radiotelemetry was used to track blossom bats (Syconycteris australis) at Iluka and Harrington in
northern New South Wales. A total of 31 bats was tracked to 110 roosts. Bats foraged on nectar and
pollen in Banksia integrtfolia heathland, but roosted 50-4000m away in littoral rainforest. Bats showed
a strong fidelity to their feeding area (about 13ha), returning to their original capture point each night
and spending a large proportion of their foraging time there. After leaving their roost, adults spent,
on average, 45% of their time active and remained in heathland throughout the night. All age-sex
classes roosted solitarily during the day amongst rainforest foliage, usually in the subcanopy layer.
Most roosts were occupied for one day only and adults were more roost-mobile than juveniles.
Mean movements between roosts were greater at Harrington (125m), where the rainforest is fragmented,
than at Iluka (42m), where rainforest is intact. Bats shifted their roosts seasonally, from the rainforest
edge in winter to the rainforest interior in spring/autumn. This behaviour allows for avoidance
of cold temperatures inside the forest in winter and of hot temperatures of the forest exterior in
spring/autumn. A further possible response to the seasonal climate prevailing at the study area was a
reduction in the commuting distance (from roosts to feeding areas) from autumn/spring (1.4km) to
winter (0.8km). Such flexible roosting and foraging strategies may be effective in allowing S. australis
to exploit subtropical and temperate areas of Australia.
Cost-effectiveness of poison bait trails for control of house mice in mallee cereal crops.
Authors: Mutze GJ
Published: June 2005

Damage by house mice (Mus domesticus) to a maturing wheat crop was controlled by laying thin trails
of poisoned wheat through the crop. Mouse population densities at treatment were about 70 mice ha-1.
Mouse numbers were reduced by 100% within 1 week; at harvest, 9 weeks later, mouse numbers were
still reduced by 46% relative to 3 untreated crops. That level of mouse control reduced damage to the
crop by more than 808, but treatment was barely cost-effective because of the moderate level of
damage in untreated crops and the low wheat prices in that year. Treatment is likely to be costeffective
given mouse densities of at least 100 mice ha-1 or higher wheat prices, but cost-effectiveness
depends greatly on the cost of rodenticide used.
Ecology of the rufous hare-wallaby, Lagorchestes hirsutus Gould (Marsupialia : Macropodidae) in the Tanami Desert, Northern Territory.II Diet and feeding strategy.
Authors: Lundie-Jenkins G , Phillips CM , Jarman PJ
Published: June 2005

The diet preferences and selectivity of the rufous hare-wallaby in the Tanami Desert were examined at
a number of sites and over a number of seasons by microscopic analysis of faecal pellets and direct
observations. Perennial grasses were the most consistent plant items in the diet. Grass seeds were
seasonally important as were the seeds and bulbs of sedges. Species of dicots were also used but most
represented only minor components in the diet. Several species of plant common to the area were
noticeably absent from the diet.
Differences in the diets between four sites of varying floristic composition and fire history were
consistent with differences in vegetation cover at each site. Overall, the absolute proportions and ratios
of monocots and dicots and of leaf and seed portions were strongly similar for all sites, as were
seasonal changes in the proportions of the four main plant categories (monocots, dicots, seeds and
fruits). These changes correlated with local rainfall. Comparisons of plants eaten and plants available
indicate the hare-wallabies' preference for monocots, particularly seed and fruit components. In contrast
consumption of dicots was influericed by the declining quality of other preferred plants. Insects were
seasonally important in the diet and appear to be a potentially important nitrogen supplement during
drier times.
The feeding strategy of the rufous hare-wallaby is flexible and enables it to exploit fully food
resources whose availability is often limited in both time and space. During droughts it seems likely that
the species is food stressed and this could lead to localised declines.
The distribution and abundance of the burrowing bettong (Marsupialia : Macropoidea)
Authors: Short J , Turner B
Published: June 2005

The burrowing buttong (Bettongia lesueur) has been extinct on mainland Australia since the early
1960s, but was believed to persist on four islands off the coast of Western Australia-Bernier, Dorre,
Barrow and Boodie. We surveyed these islands in 1988-89 to ascertain the status of bettongs and other
endangered mammals.
Bettongs were widespread and comparatively abundant on three islands but absent from the fourth.
Bettongs occurred at estimated densities of c. 14-17km-2 on Bernier, Dorre and Barrow Islands,
suggesting approximate minimum populations of 650, 1000 and 3400 respectively and a total minimum
population for the species of c. 5000 individuals. It would appear that a poisoning campaign in 1985
to eliminate Rattus rattus from Boodie Island also eliminated the bettong. The burrowing bettong has
apparently been absent from a fifth island and its type locality, Dirk Hartog Island in Shark Bay, since
early this century.
The vulnerability of this species is highlighted by its extinction on mainland Australia and by
the loss of two of its five island populations. It now occupies less than 0.01% of its historical range.
Its status as rare and endangered is justified.
Avian Seed Dispersal in and Near Subtropical Rainforests.
Authors: Green RJ
Published: June 2005

The behaviour of avian visitors to 23 species of subtropical Australian rain forest plants was observed in the Lamington and Border Ranges National Parks on the Queensland/New South Wales border to determine potentially important seed dispersers, seed predators and fruit thieves.
Home range of the swamp wallaby, Wallabia bicolor
Authors: Troy S , Coulson G
Published: June 2005

Home range in the swamp wallaby, Wallabia bicolor (Marsupialia : Macropodoidea) was examined using
radio-tracking in a 150-ha remnant of mixed eucalypt forest at Healesville, Victoria. Three methods
were used to calculate home-range size: minimum convex polygons, fourier transform MAP(O.95) and
MAP(0.50) estimation, and harmonic mean 50% isopleths and 95% isopleths. The minimum convex
polygon method produced the largest estimate of home-range area (16.01 +/-.45 ha). Each method
required a different number of fixes before home-range area estimates reached an asymptote. These data
showed that W. bicolor have small, overlapping home ranges and that the shape of the home range
varied between individuals. Home-range area was larger than previously reported for this species, and
there was no significant difference between the sexes in home-range size.
Extension of the breeding season of the New Holland Mouse: a response to above-average rainfall
Authors: Fox BJ , Higgs P , Luo J
Published: June 2005

The New Holland mouse, Pseudomys novaehollandiae, has been reported to have a distinct 5-month breeding season, August to early January, with occasionally an extension to March. Hence it is classified as primarily a seasonal breeder with some of the flexibility of an opportunistic breeder. We present evidence of an extension of the 1991-92 breeding season to at least 10 months, from mid-October or earlier, to late July. In May 62.5% of females were pregnant or lactating whereas 25-44% were pregnant or lactating at different sites in July. Our data from sand-mined dunes extend from Bridge Hill Ridge at the northern end of the Myall Lakes National Park to Tomago near the mouth of the Hunter River. We collate data from studies over the last 20 years, documenting extended breeding in 8 different years, 6 from one region, and at least 4 from another. Twenty years of rainfall data from nearby weather stations in the two regions show extended breeding to be a response to climate, when rainfall between September and March exceeds a threshold value of 750-800mm (approximately 120% of the long-term average), with at least 420-480mm falling during the first three months of the year (approximately 130% of the long-term average). While rainfall appears to be the ultimate factor, we support Kemper''s hypothesis that the proximal factor is most likely to be the abundance or quality of food produced by above-average late summer rainfall.
Population Dynamics of Feral Pigs (Sus Scrofa) in a Tropical Riverine Habitat Complex.
Authors: Caley P
Published: June 2005

Employed mark-recapture techniques to monitor trends in the population density of feral pigs in a tropical woodland habitat containing cereal crops, and compared density indices in this habitat with other similar habitat not containing cereal crops. Over the duration of this study there was no significant trend for increase or decrease but population density fluctuated seasonally between 2.2 and 3.5 pigs kg-2 in the woodland site containing cereal crops. A numerical response model was developed relating observed exponential rate of increase of feral pigs to antecedent rainfall. The model estimated the maximum exponential rate of increase (rmax) of feral pigs to be 0.065 plus or minus 0.17 (s.e.) month-1 or 0.78 plus or minus 0.21 (s.e.) year-1. Comparison of indices of population density of feral pigs in woodland habitat with cereal crops and similar woodland habitat without cereal crops demonstrated that the presence of intensive cereal cropping increased population density of feral pigs almost 4-fold. Population density in the woodland habitat without cereal crops was estimated to be 0.8 pigs kg-2. The response to rainfall and the variation in density in response to an increase in the amount of available food is interpreted as evidence that feral pig populations are limited primarily by food availability.
Seasonal Patterns in Bait Consumption by Feral Pigs (Sus Scrofa) in the Hill Country of South-Eastern Australia.
Authors: Mcilroy JC , Gifford EJ , Forrester RI
Published: June 2005

Both fermenting wheat and bran/pollard pellets were readily accepted as bait throughout the year by feral pigs (Sus scrofa) in Namadgi National Park, Australian Capital Territory. Birds mainly ate wheat bait, particularly during winter. Other animals occasionally fed on both types of bait, mainly during autumn and winter. Covering baits with forest-floor litter did not significantly affect their discovery and consumption by pigs or by other animals. The proximity of the pigs to the bait line and their appetite for bait appeared to be the main factors responsible for seasonal differences in bait consumption. Trail-baiting campaigns against pigs in similar hill country areas are likely to be more effective during late autumn than other seasons because more pigs are likely to be close to the trails then and more quickly find and eat greater quantities of bait.
A new ear-tag for rabbits
Authors: Fraser KW , Gibb JA , Ward GD
Published: June 2005

We describe a cylindrical plastic ear-tag for rabbits (Oryctolagus cuniculus) that is inexpensive to construct,
easy to attach, and highly suitable for field studies. Tags are visible in daylight with the aid of
binoculars or telescope at distances up to about 200 m, and up to about 150m at night with the aid
of a spotlight. Annual rates of tag loss are low (7%) in grassland habitat but may be higher in scrub
habitat.
Habitat Requirements of the Tasmanian Bettong (Bettongia Gaimardi), a Mycophagous Marsupial.
Authors: Taylor RJ
Published: June 2005

The habitat requirements of the Tasmanian Bettong (Bettongia gaimardi) were investigated by assessed density at 20 sites covering a broad range of dry sclerophyll forest types throughout the species' range. There was no consistent relation between the density of bettongs and the floristics of an area. Bettongs did not occur in areas with dense undergrowth. However, the occurrence of an open undergrowth did not guarantee the presence of bettongs. The abundance of bettongs on areas with an open undergrowth was related to the extent of mycorrhizal root development, sporocarps of mycorrhizal fungi forming the major component of the diet of bettongs. The highest densities of bettongs occurred in areas with infertile soils. It was suggested that since mycorrhizal fungi develop and sporulate well in soils of low fertility, this factor may be important in indirectly influencing bettong numbers.
Avian nest predation in modified and natural habitats in troprical Queensland: an exeperimental study.
Authors: Laurance WF , Garesche J , Payne CW
Published: June 2005

Predation on artificial avian ground-nests was assessed from March to December 1991 in rainforest
and nearby modified habitats in tropical Queensland. Data from 610 experimental nests were used to
determine relative predation intensity in five types of habitat or microhabitat. Nest predators were
identified with live-traps, with baited grease-plates and by regular observations of 380 additional nests.
Predation intensity was patchy but often heavy in forested habitats (rainforest interiors, secondary
forest, rainforest-pasture edges, and a rainforest-secondary forest edge) and negligible in adjoining
cattle pastures. Forest edges exhibited no obvious edge-interior gradients in predation intensity. Most
predation occurred at night in rainforest (88%) and secondary forest (61%), and patterns of egg damage
suggested that mammals were responsible for most (>71%) nest predation. A combined nest-predation
and live-trapping experiment on six study plots revealed that the abundance of white-tailed rats (Uromys
caudimaculatus) was a highly effective predictor of local predation intensity (F=30.15, r*2=0.85,
P=0.004). One of Australia's largest rodents, the white-tailed rat may be a key opportunistic predator
of some bird nests in north Queensland rainforest.
Identification of sex of Adelie penguins from observations of incubating birds
Authors: Kerry KR , Clarke JR , Else GD
Published: June 2005

The suggestion that sex of Adelie penguins, Pygoscelis adeliae, might be assigned by observing which
member of the pair (the male) takes the first long incubation shift (Anon. 1991) was examined for
each of the 1990-91, 1991-92 and 1992-93 breeding seasons. There was an 8- or 9-day period when
more than 90% of the incubating birds were male and a 6- or 7-day period when more than 90% of
the birds were female. The dates of these peak periods of male or female presence overlapped by only
2-5 days between the three seasons but were constant to within 2 days relative to the commencement
of egg laying. Peak presence of males occurred 15-21 days after the appearance of the first egg in the
colony and peak presence of females after 33-36 days from this date. In all three seasons male birds
could be identified with 91.8-98.6% accuracy within 15-21 days after the first sighting of an egg.
The method provides, therefore, a means of identifying the sex of Adtlie penguins with an accuracy
greater than 90% and is applicable to whole colonies containing several hundred pairs without recourse
to continuous observations or capturing the birds.
Measurement of immunoreactive progestins excreted in faeces as a potential indicator of pregnancy
Authors: Larter NC , Arcese P , Rajamahendran R , Gates CC
Published: June 2005

We measured the concentration of immunoreactive progestins extracted from 41 faecal samples of
female wood bison (Bison bison athabascae) as a potential indicator of pregnancy. The concentration
of faecal progestins fell into two distinct groups, with an approximate 4-fold difference in mean
progestin level (1391.9ng g-1 and 58269ng g-1). We suggest that measuring progestin concentration
in the faeces of free-ranging animals is a non-invasive method that could be used to assess pregnancy
rate.
Ducks, hunters and rainfall at two sites in southern inland New South Wales
Authors: Briggs SV , Brickhill JG , Kingsford RT , Hodgson PF
Published: June 2005

Duck hunters have been surveyed on the opening morning of duck seasons since 1972 at Lake Cowal
and Barrenbox Swamp in southern inland New South Wales. Mean numbers of ducks shot per hunter
on opening morning reflected the numbers of ducks at the sites two to three weeks previously. At
Barrenbox Swamp, but not at Lake Cowal, mean bag sizes were inversely related to recent local rainfall.
Mean bag sizes on opening morning at Lake Cowal and Barrenbox Swamp did not diminish following
reduction of the opening-day bag limit from 20 to 10 ducks per day in 1988. Generally, numbers of
ducks and mean bag sizes at Lake Cowal and Barrenbox Swamp have not declined or increased since
1972 (exceptions are increased numbers but decreased bag sizes of Pacific black duck at Barrenbox
Swamp, and increased bag sizes of maned duck at Lake Cowal). At neither hunting site were numbers
of ducks related to mean bag sizes in the previous year. In summary, hunting does not appear to
be adversely affecting numbers of major species of game ducks at either Lake Cowal or Barrenbox
Swamp.
Observations on the effectiveness of shooting feral pigs from helicopters.
Authors: Saunders G
Published: June 2005

The use of helicopters for the shooting of feral pigs in western New South Wales has become
increasingly popular and widespread. Studies were conducted to evaluate the effectiveness of this practice
in terms of population reduction, rate of population recovery and cost. The study site was an area of
120 km*2 on the southern edge of the Macquarie Marshes. Estimated population reductions, calculated
by the index-removal method, over two consecutive years were 80 and 65%. The associated rate of
increase (r) in the 12 months following the first population reduction was 1.34, which is equivalent
to a recovery of 77% in numbers. Results and levels of control inputs were collated for an additional
consecutive year and compared with other studies. Management implications from this study are also
considered.
The effects of fire-driven succession and rainfall on small mammals in spinifex grassland at Uluru National Park, Northern Territory
Authors: Masters P
Published: June 2005

Fire-driven succession and a period of high rainfall had a pronounced effect on the distribution and
abundance of small mammals inhabiting spinifex grassland in Uluzu National Park from 1987 to 1990.
Species richness and abundance were generally higher on sites burnt in 1976, where six species
(Pseudomys hermannsburgensis, Pseudomys desertor, Mus domesticus, Dasycercus cristicauda, Ningaui
ridei and Sminthopsis youngsoni) were caught more frequently. Two species (Notomys alexis and
Sminthopsis hirtipes) were more abundant on sites burnt in 1986. Murid rodent numbers fluctuated
substantially following high rainfall. The number of individuals increased 100-fold, and species richness
increased from two to four when P. desertor and M. domesticus appeared in the second year of the
study. In contrast, captures of dasyurid marsupials increased only slightly over the three years, with the
most dramatic increase occurring for D. cristicauda. This study highlights the importance of fire as
a management tool. Patch burning within spinifex grasslands maximises species diversity of small
mammals by ensuring that suitable successional states are present at all times. This is particularly
important for species that are restricted in their distribution, such as D. cristicauda
Macropod studies at Wallaby Creek. IX Exposure and responses of eastern grey kangaroos to dingoes
Authors: Jarman PJ , Wright SM
Published: June 2005

Kangaroos at Wallaby Creek lived with the persistent presence of dingoes in the valley, there being no
place, time of year or of day when kangaroos could be free of risk. An adult kangaroo might encounter
dingoes a few hundred times in its life. Dingoes appeared not to be selective for the sizes of groups of
kangaroos that they contacted. Large adult males and females with medium pouch young were overrepresented
in the samples of kangaroos contacted by dingoes. No kangaroos ignored the detected
presence of dingoes; all became alert, and most fled. The distances at which they became alert to a
dingo group depended upon the kangaroo group's size, larger groups never being surprised by dingoes
at short range as were some smaller groups. On average larger groups fled when the dingoes were
further away. Among classes of kangaroos, large adult males fled least far, and tended to react to
dingoes less strongly (in terms of alertness or flight) than other classes. They also exhibited two forms
of defence, taking to water when pursued and warding off attack, that other classes did not show.
The Strategic Use of Rodenticides Against House Mice (Mus Domesticus) Prior to Crop Invasion.
Authors: Kay BJ , Twigg LE , Nicol HI
Published: June 2005

This study evaluated the effect of baiting refuge habitats around irrigated soyabeans with bromadiolone to control house mice and reduce their invasion of crops. Generalized linear models were constructed and used to predict changes in mouse abundance over time in both refuge and crop habitats of treated and untreated plots. Compared with untreated plots, bromadiolone significantly reduced the number of mice inhabiting the refuge habitat and reduced the rate at which mice invaded and colonized the adjacent crops. Despite this, no significant reductions in damage were detected as mice numbers failed to reach critical densities for crop damage on the untreated plots. This indicates a need for short-term predictive models when considering control strategies.
Toxicity of a tropical Australian frog, Litoria dahlii, to sympatric snakes
Authors: Madsen T , Shine R
Published: June 2005

Although Litoria dahlii is one of the most abundant frog species of floodplain habitats in tropical
Australia, it is rarely eaten by snakes. Force-feeding trials showed that L. dahlii is highly toxic to
snakes: ingestion of even a single large frog was potentially fatal for pythons (Liasis childreni and
Liasis fuscus), colubrids (Dendrelaphispunctulatus and Stegonotus cucullatus) and elapids (Acanthophis
praelongus and Demansia atra). Only one species, the keelback, Tropidonophis mairii (Colubridae),
could consume these frogs without ill effects. Keelbacks were also the only snakes recorded to eat these
frogs in the wild. The fact that these abundant tropical frogs are highly toxic to most snakes, and
generally not eaten by them, suggests that the anurophagous snakes of the Australian tropics assess
amphibian chemical defences before consuming their prey. Thus, these snakes may be better-able to deal
with the invasion of cane toads, Bufo marinus, than has been generally supposed.
Evaluation of the Efficacy of 1080 Poisoning of Red Foxes Using Visitation to Non-Toxic Baits as an Index of Fox Abundance.
Authors: Thompson JA , Fleming PJS
Published: June 2005

Visits of foxes to non-toxic baits were used to derive fox abundance indices at 4 sites in north-eastern New South Wales. A 1080 (sodium fluoracetate) poisoning campaign resulted in a mean population reduction of 69.5% (s.d. = 4.9). Fox densities before baiting, calculated using the index-removal-index method, ranged from 4.55 to 7.16 foxes km-2. Visitation to non-toxic baits is recommended as a reliable estimate of relative density. This study investigated the efficacy of 1080 baiting as a technique for the control of foxes in tableland environments. The implications of the estimated fox densities and population reductions on fox control in agricultural areas and in the context of rabies are discussed.
The potential of electric shock for humane trapping of brushtail possums, Trichosurus vulpecula
Authors: Dix ID , Jolly SE , Bufton LS , Gardiner AI
Published: June 2005

The Australian brushtail possum is a major pest in New Zealand, and a device to kill possums in the
wild by electric shock has been proposed. This investigation was to determine the best waveform and
energy level for an electric device to humanely kill possums. The criterion set was a shock which
would cause ventricular fibrillation and result in irreversible unconsciousness within a few minutes.
Anaesthetised possums were shocked with sinusoidal alternating currents, direct current bursts and
impulse waveforms of varying intensities and durations. An electrocardiogram was used to monitor the
cardiac response. Although sinusoidal waveforms of a long duration did disrupt the heartbeat and
might result in death, even shocks of very high energy levels did not consistently result in ventricular
fibrillation. The use of electricity to trap and kill possums appears unacceptable on humanitarian
grounds.
Habitat selection by helmeted honeyeaters
Authors: Pearce JL , Burgman MA , Franklin DC
Published: June 2005

The realised niche of the helmeted honeyeater, in terms of the floristic and structural attributes of the
vegetation, was determined using logistic discrimination. The vegetation was divided into two communities,
Eucalyptus camphora swampland and E. viminalis-dominated riparian forest, based on
differences observed in other studies on foraging behaviour within these two communities. The variables
describing the realised niche of the helmeted honeyeater in the E. camphora community were a high
bark index, a large number of E. camphora stems and the presence of surface water. The results for
the E. viminalis community were less conclusive, but suggest that a deep eucalypt canopy may be
important. These variables relate to the feeding and breeding biology of the helmeted honeyeater.
Habitat models of this form will allow appropriate habitat management strategies for Yellingbo State
Nature Reserve to be developed, as well as allow the suitability of potential helmeted honeyeater
release or relocation sites to be assessed.
The use of artifical perches to increase predation on house mice (mus domesticus) by raptors
Authors: Kay BJ , Twigg LE , Korn TJ , Nicol HI
Published: June 2005

Changes in raptor and mouse abundance over time in response to the introduction of artificial perches
for raptors were analysed using generalised linear models. The placement of artificial perches around
the perimeter of irrigated soybean crops significantly increased the number of diurnal raptors visiting
and hunting over these crops compared with untreated crops. This increased hunting pressure reduced
(a) the rate at which the mouse population increased in the crops and (b) the maximum mouse
population density. These effects were greater when artificial perches were placed at 100-m spacings
rather than 200-m spacings. No significant reductions in mouse damage were detected as mice failed
to reach threshold densities for crop damage on the untreated plots. Despite this, the use of artificial
perches to attract birds of prey may be a useful addition to rodent management strategies.
Patterns of grazing on coastal dune systems by insular populations of two species of macropod
Authors: Ramsey DSL , Engeman RM
Published: June 2005

A study of grazing patterns on a coastal dune system on South Stradbroke Island, Queensland, by two
species of wallaby was undertaken. Utilisation of sand spinifex (Spinifex sericeus) by agile wallabies
(Macropus agilis) and swamp wallabies (Wallabia bicolor) was highly variable between different sites
on the dune system. Although wallaby activity on secondary dune strata was significantly higher than
on the primary dune, this was not reflected statistically in spinifex grazing levels. However, spinifex
stolons on the toe of the primary dune were heavily grazed. Grazing levels on dune systems on the
island were negatively associated with the width of the frontal dune and the relative area of open forest
vegetation adjacent to the dune system.