bluuebunny/crossref_metadata_2025 huggingface dataset:
Land‐cover change and vegetation dynamics across Africa
Authors: Linderman Marc , Rowhani Pedram , Benz David , Serneels Suzanne , Lambin Eric F.
Published: June 2005

Using improved metrics and recently available MODerate resolution Imaging Spectrometer (MODIS) data, we examined the magnitude, extent, and nature of changes in photosynthetic activity and its timing across Sub‐Saharan Africa. Changes in overall vegetation activity and shifts in its timing have considerable implications for a variety of processes including surface‐atmosphere energy exchanges, terrestrial sources and sinks of carbon, the contribution of local evapotranspiration to the water cycle, disturbance regimes such as fires and pests, and the food security of societies using these ecosystems. While previous studies have examined broad‐scale trends in phenology or provided more detailed estimates of land‐cover conversion in the tropics, less is known of the year‐to‐year dynamics of vegetation. Here we quantified the overall changes in vegetation activity for each year between 2000 and 2004 and examined the proportion linked to differences in phenology and overall photosynthetic activity. In addition, we examined the nature of these changes in terms of frequency and duration, the proportion per ecosystem, identified areas of intensive change, and discuss the potential consequences of these changes. We found that most interannual change was not from shifts in timing or phenology, but rather largely due to differences in the amount of annual photosynthetic activity. In fact, there was as much as a 5% annual difference in vegetation activity across the continent. The changes were likely climate driven with particular vegetation types most susceptible to interannual change with high spatial and temporal variability found across the continent.
Distribution functions of a spurious trend in a finite length data set with natural variability: Statistical considerations and a numerical experiment with a global circulation model
Authors: Nishizawa S. , Yoden S.
Published: June 2005

A linear trend estimated from a finite‐length data set with random internal variability has a spurious component which is a difference from the true trend caused by changes in external conditions or parameters. Some moments and distribution functions of the spurious trend depending on the length of data are derived theoretically under general statistical assumptions. When the internal variability has a normal distribution, the spurious trend also has a normal distribution. In general cases of nonnormal distributions, we derive the distribution function of the spurious trend by the Edgeworth expansion. A few low‐order moments of the internal variability are necessary to obtain the approximate distribution function from the expansion. Population moments of the internal variability of a simple global circulation model are calculated using a 15,200‐year data set generated by a numerical experiment with a purely periodic annual forcing. Dependence of the estimation error of sample moments on the length of data is computed to evaluate an appropriate sample size for each moment. An ensemble experiment with the same model is used to estimate the detectability of a cooling trend in the stratosphere from a finite length data set with internal variability. Hypothesis tests for the statistical significance of the estimated trend are made: Student's t test, bootstrap test, and the more accurate test using the distribution function derived by the Edgeworth expansion. In the regions and seasons in which kurtosis of the internal variability is large the assumption that the spurious trend has a normal distribution is not appropriate, and the significance derived by the t test is different from that by the test using the Edgeworth expansion.
Calibration of the planktonic foraminiferal Mg/Ca paleothermometer: Sediment trap results from the Guaymas Basin, Gulf of California
Authors: McConnell Martha C. , Thunell Robert C.
Published: June 2005

The Mg/Ca ratio has been measured in two surface‐dwelling species of planktonic foraminifera, Globigerinoides ruber and Globigerina bulloides, from biweekly sediment trap samples collected in Guaymas Basin, Gulf of California, between August 1992 and November 1997. The Guaymas Basin experiences significant seasonal changes in sea surface temperature (SST) (∼16°–33°C) and thus is an ideal location for testing the temperature dependence of Mg incorporation into foraminiferal calcite. The planktonic foraminiferal Mg/Ca ratios are directly compared with concurrent temperature measurements from the study site. The results from the sediment trap study reveal a strong positive correlation between SST and the Mg/Ca ratio in both G. ruber (r2 = 0.86) and G. bulloides (r2 = 0.90). The Mg/Ca ratio increases exponentially by 7% per 1°C change in temperature for G. ruber and by 6% for G. bulloides. These results indicate that the Mg/Ca ratio in G. ruber and G. bulloides accurately records the measured seasonal surface temperature cycle and interannual variability in the Guaymas Basin within ±1°C. The greatest deviation between Mg/Ca–estimated SST and observed SST occurs in the spring and fall for both species. This variability is attributed to rapidly changing hydrographic conditions and possible offset between the time of calcification and the temperature measurements. In addition, G. ruber and G. bulloides exhibit very high Mg/Ca ratios during the strong El Niño–Southern Oscillation years of 1992 and 1997, verifying their potential to record SST up to 33°C and 28°C, respectively. The trace metal data are compared with foraminiferal oxygen isotope and alkenone measurements made on the same suite of sediment trap samples to assess the internal consistency of these temperature proxies. Strong correlations exist between the δ18O and Mg/Ca for G. ruber (r2 = 0.86) and G. bulloides (r2 = 0.79). Similarly, sea surface temperature estimates from Mg/Ca ratios are in good agreement with alkenone‐derived temperature estimates (r2 = 0.89 for G. ruber and r2 = 0.81 for G. bulloides).
Kinematic analysis of the southern Iberian shear zone and tectonic evolution of the Acebuches metabasites (SW Variscan Iberian Massif)
Authors: Díaz Azpiroz Manuel , Fernández Carlos
Published: June 2005

The Acebuches metabasites constitute a slice of oceanic crust located at the Variscan suture between the Ossa Morena and the South Portuguese zones (Iberian Massif). The emplacement of the metabasites onto the accretionary prism was associated with the activity of the southern Iberian shear zone. Careful measurements of the fabrics and structures related to this shear zone show consistent kinematic criteria pointing to the presence of a simple shear component, with an oblique predominantly left‐lateral sense of displacement. The data are consistent with existing models of triclinic or oblique shear zones considering coeval simple shear and pure shear components. These models provide a satisfactory explanation of the observed spatial variations in the foliation, lineation and fold hinge data. The kinematics of other shear deformations, older and younger than the southern Iberian shear zone, have also been established. These results offer new insights into the tectonic evolution of this suture of the Variscan belt, and show how complex transpressional strains can arise during oblique crustal deformation associated with the motions of tectonic plates.
Linking flood frequency to long‐term water balance: Incorporating effects of seasonality
Authors: Sivapalan M. , Blöschl G. , Merz R. , Gutknecht D.
Published: June 2005

Derived flood frequency models can be used to study climate and land use change effects on the flood frequency curve. Intra‐annual (i.e., within year) climate variability strongly impacts upon the flood frequency characteristics in two ways: in a direct way through the seasonal variability of storm characteristics and indirectly through the seasonality of rainfall and evapotranspiration which then affect the antecedent catchment conditions for individual storm events. In this paper we propose a quasi‐analytical derived flood frequency model that is able to account for both types of seasonalities. The model treats individual events separately. It consists of a rainfall model with seasonally varying parameters. Increased flood peaks, as compared to block rainfall, due to random within‐storm rainfall time patterns are represented by a factor that is a function of the ratio of storm duration and catchment response time. Event runoff coefficients are allowed to vary seasonally and include a random component. Their statistical characteristics are derived from long‐term water balance simulations. The components of the derived flood frequency model are integrated in probability space to derive monthly flood frequency curves. These are then combined into annual flood frequency curves. Comparisons with Monte Carlo simulations using parameters that are typical of Austrian catchments indicate that the approximations used here are appropriate. We perform sensitivity analyses to explore the effects of the interaction of rainfall and antecedent soil moisture seasonalities on the flood frequency curve. When the two seasonalities are in phase, there is resonance, which increases the flood frequency curve dramatically. We are also able to isolate the contributions of individual months to the annual flood frequency curve. Monthly flood frequency curves cross over for the parameters chosen here, as extreme floods tend to mainly occur in summer while less extreme floods may occur throughout the year.
Long‐term suppression of wetland methane flux following a pulse of simulated acid rain
Authors: Gauci Vincent , Dise Nancy , Blake Stephen
Published: June 2005

Wetlands are a potent source of the radiatively important gas methane (CH4). Recent findings have demonstrated that sulfate (SO42−) deposition via acid rain suppresses CH4 emissions by stimulating competitive exclusion of methanogens by sulfate‐reducing microbial populations. Here we report data from a field experiment showing that a finite pulse of simulated acid rain SO42− deposition, as would be expected from a large Icelandic volcanic eruption, continues to suppress CH4 emissions from wetlands long after the pollution event has ceased. Our analysis of the stoichiometries suggests that 5 years is a minimum CH4 emission recovery period, with 10 years being a reasonable upper limit. Our findings highlight the long‐term impact of acid rain on biospheric output of CH4 which, for discrete polluting events such as volcanic eruptions, outlives the relatively short‐term SO42− aerosol radiative cooling effect.
Climatological validation of stratospheric temperatures in ECMWF operational analyses with CHAMP radio occultation data
Authors: Gobiet A. , Foelsche U. , Steiner A. K. , Borsche M. , Kirchengast G. , Wickert J.
Published: June 2005

A climatological validation of the thermal structure of European Centre for Medium‐Range Weather Forecasts (ECMWF) operational analyses with a new 2.5‐year dataset derived from the CHAllenging Minisatellite Payload (CHAMP) radio occultation (RO) satellite mission was performed. Close overall agreement was found in the 10–30 km altitude region, with seasonal zonal mean temperature biases generally smaller than 0.5 K. Apart from that, discrepancies in the Austral polar vortex region (cold biases up to −2.5 K, warm biases up to +3.5 K) and a cold bias of the analysis at the low‐latitude tropopause (up to −2 K) were revealed. The polar vortex bias can be clearly attributed to the ECMWF analysis and data assimilation system and the tropopause bias is strongly indicated to be related to the smaller tropopause variability and the lower vertical resolution in the analysis. The study underlines the utility of RO data as global long‐term climate reference datasets.
Mars at very low obliquity: Atmospheric collapse and the fate of volatiles
Authors: Kreslavsky M. A. , Head J. W.
Published: June 2005

The obliquity of the Martian spin axis is known to undergo quasiperiodic oscillations superposed over chaotic long‐term variations. It is probable that within past history there were geologically long periods when the obliquity oscillated around low (10–15°) mean values. During such low obliquity epochs the climate system is controlled by deposition of permanent solid CO2 deposits in the polar regions. With a simple season‐resolved energy balance model, we show that as the atmosphere collapses, surface topography plays a major role in CO2 condensation and sublimation processes, defining distribution and dynamics of CO2 deposits. Thick CO2 deposits are formed at steep pole‐facing topographic slopes at moderately high latitudes, not at the poles. The total mass of the deposits is not a function of obliquity, but strongly depends on the pre‐history of the climate system. We outline criteria to identify such low‐obliquity epochs in Mars history.
Plasma electrons above Saturn's main rings: CAPS observations
Authors: Coates A. J. , McAndrews H. J. , Rymer A. M. , Young D. T. , Crary F. J. , Maurice S. , Johnson R. E. , Baragiola R. A. , Tokar R. L. , Sittler E. C. , Lewis G. R.
Published: June 2005

We present observations of thermal (∼0.6–100eV) electrons observed near Saturn's main rings during Cassini's Saturn Orbit Insertion (SOI) on 1 July 2004. We find that the intensity of electrons is broadly anticorrelated with the ring optical depth at the magnetic footprint of the field line joining the spacecraft to the rings. We see enhancements corresponding to the Cassini division and Encke gap. We suggest that some of the electrons are generated by photoemission from ring particle surfaces on the illuminated side of the rings, the far side from the spacecraft. Structure in the energy spectrum over the Cassini division and A‐ring may be related to photoelectron emission followed by acceleration, or, more likely, due to photoelectron production in the ring atmosphere or ionosphere.
Downstream structures of interplanetary fast shocks associated with coronal mass ejections
Authors: Kataoka R. , Watari S. , Shimada N. , Shimazu H. , Marubashi K.
Published: June 2005

We investigate 17 coronal mass ejection (CME) events identified by the ACE spacecraft during solar cycle 23, focusing upon the fine structures of the sheath region between the CME and its associated shock to find their dependence on the shock parameters. We observe the planar magnetic structure (PMS) downstream of a quasi‐perpendicular shock when the Alfvén Mach number >2.0. Here, the PMS is characterized by the magnetic fields changing directions abruptly and intermittently within a plane parallel to the shock plane. The downstream PMS does not form when a magnetic cloud with β value <0.05 exists just upstream of a shock with Alfvén Mach number <2.0. The sheath magnetic fields become highly turbulent when the shock angle is <60 and/or the upstream β value is >0.5 and the upstream is dominated by Alfvenic fluctuations.
Sub‐mesoscale coastal eddies observed by high frequency radar: A new mechanism for delivering nutrients to kelp forests in the Southern California Bight
Authors: Bassin Corinne J. , Washburn Libe , Brzezinski Mark , McPhee‐Shaw Erika
Published: June 2005

Sub‐mesoscale eddies are described along the mainland coast of the Santa Barbara Channel based on observations from a network of high frequency (HF), current‐measuring radars and near‐shore moorings. The eddies are 4–15 km in diameter and typically last about 2 days, although some last up to 6 days. Most eddies within the radar coverage area are anti‐cyclonic with relative vorticities of −0.4 f to −0.8 f where f is the Coriolis parameter, but cyclonic eddies are also observed. Moored observations over the inner shelf (12 m water depth) of a sequence of two eddies in December 2001 show an increase in nitrate plus nitrite from the background levels of 1–2 μM to a maximum of 10–12 μM when the eddies are present. We speculate that these eddies are an important transport mechanism for nutrients and biogenic particles to inner shelf ecosystems of the Southern California Bight.
Turnover of Sodium and Water by Free-Living Rabbits, Oryctolagus Cuniculus.
Authors: Green B , Dunsmore J , Bults H , Newgrain K
Published: June 2005

Four places in New South Wales were chosen that had a permanent water supply and vegetation with very low or very high Na content, or no surface water during the study and medium, or low to medium, Na content. Wild rabbits (Oryctolagus cuniculus) were caught in those places, given 22NaCl and 3H2O by intraperitoneal injection and held for 4 to 5 h, then blood samples were taken and the rabbits were weighed, marked and released at the point of capture. After another 8 to 23 days they were recaptured and weighed, and blood samples were taken. Between the 7 or 8 values for different places and dates, mean bodyweight ranged from 937 to 1650 g, exchangeable Na from 37.37 to 50.10 mEq/kg bodyweight or 48.78 to 67.93 mEq/litre body water, Na turnover from 0.51 to 13.95 mEq/kg bodyweight daily, Na biological half-life from 2.3 to 55.0 days, total body water 677 to 777 ml/kg, water turnover 88 to 375 ml/kg daily and water half-life 1.4 to 5.6 days. Mean values are for groups of 4 to 25 rabbits. Between the 4 places, water content of vegetation ranged from 142 to 832 mg/kg fresh vegetation and, including 2 sites at one of the 4 places, Na content ranged from 0.51 to 20.98 mEq/kg fresh and 2.41 to 124.9 mEq/kg dry matter. There was a positive linear relation between Na in fresh vegetation and Na turnover rate in rabbits. The relation between water content of vegetation and water turnover in rabbits was not precise, because probably of such factors as diet selection, rain and accessibility and use of water. Lactation may have a strong effect on rabbits when water or Na is scarce, because rabbits may not ingest the faeces and urine of their young like other animals.Low rate of water turnover, especially after metabolic weight correction, demonstrated the efficiency of water conservation of rabbits and partly explained their success in dry places. Published values for other species are compared. Food items were not identified in the present work, but identification and analysis of their Na content would allow qualitative calculation of the food intake of free-living herbivores from their Na turnover.
The Toxicity of Sodium Monofluoroacetate to Wild Rabbits, Oryctolagus Cuniculus (L.), From Three Sites in Western Australia.
Authors: Wheeler SH , Hart DS
Published: June 2005

The LD50 of sodium monofluoroacetate for wild rabbits was determined in the field at three well separated sites in Western Australia, and in the laboratory using rabbits from one of the sites. At one site the rabbits had not been exposed to fluoroacetate, while at the other two it occurred naturally in native plants of the genera Gastrolobium and Oxylobium, as well as having been used in rabbit-control baits. No differences were detected in LD50 values from the three sites. Pressures for selection for tolerance to fluoroacetate in wild rabbits are discussed.
Multiple Laying by the Silver Gull, Larus novaehollandiae Stephens, on Carnac Island, Western Australia
Authors: Wooller RD , Dunlop JN
Published: June 2005

In 1977 and 1978, silver gulls on Carnac I., near Perth, W.A., bred continuously from March to November, with laying peaks in April, June and August-September. Many pairs laid several times
during the year, showing complex patterns of replacement and post-refractory clutches.

This prolonged breeding appears to have resulted from sustained predation pressure in an environment with few climatic or food constraints. Intra-clutch egg variation and seasonal changes in clutch and egg sizes followed the patterns common among gulls. Egg sizes in clutches laid by the same individual were very similar, irrespective of time of year.
Seasonal and Maturational Pelage Changes, and Injuries, in the Eastern Water Rat, Hydromys chrysogaster, at Griffith N. S. W.
Authors: Olsen P
Published: June 2005

Pelage changes in the water rat were followed in skins collected at Griffith, N.S.W. Females moulted in autumn and summer, and some may have moulted in spring. Males moulted in autumn and summer only. The summer coat was sparse and coarse, the winter coat was dense and fine. A diffuse moult sometimes followed the autumn moult. The majority of moults were of the sheet (or wave) type and hair replacement proceeded dorsad-caudad.

An animal's first two or three moults were rapid and related to age, and at about 6 months of age were replaced by a less rapid, seasonal moult. A diffuse type of moult became more common with age, especially in males, in which it almost entirely replaced the summer sheet moult. Changes in the quality of pelt, the timing, type and extent of moult, and injuries due to fighting are discussed in relation to photoperiod, temperature, reproductive condition, adrenal weight, body condition and social interaction.
Growth of the Eastern Quoll, Dasyurus viverrinus (Shaw), (Marsupialia) in Captivity
Authors: Merchant JC , Newgrain K , Green B
Published: June 2005

The growth and development, from 10 to 270 days old, of eastern quolls in a captive colony was
recorded. Young were able to detach from the teat by 65 days of age and their eyes were open by 80 days.
Statistically significant differences in some measurements from males and females were found as early
as 85 days of age. The weaning period commenced at 102 days ofage, and coincided with eruption ofthe
first molar teeth. Total independence, determined by the cessation of lactation in the mother, was as
early as 142 days in litters of one or as late as 200 days in larger litters. There was a high correlation
between litter size and age at independence.
Lactation was maintained in all previously suckled mammary glands of adult females after the death
of young aged 65 days or over if some siblings remained. This was due to the ability of young of this age
to detach and reattach to the teats at will. The implication of this observation is that the commonly held
view that the numbers of surviving young in marsupial litters corresponds to the number of lactating
teats in the adult female may not always be correct.
The Toxicity and Acceptability of Warfarin and 1080 Poison to Penned Feral Pigs.
Authors: Hone J , Kleba R
Published: June 2005

Experiments were conducted which examined the toxicity and acceptability of warfarin and 1080 poison to penned feral pigs. Warfarin was very toxic and highly acceptable. Maximum mortality was 11 of 12 at 0.08% concentration for 2 or 3 days, or 0.1% concentration for 2 days. 1080 toxicity was 2 of 19 at 0.05% for 1 day. Bait intake declined significantly when bait was poisoned with 1080. The results and their implications are discussed.
The Biology of the Yellow-Footed Antechinus, Antechinus flavipes (Marsupialia : Dasyuridae), in a Swamp Forest on Kinaba Island, Cooloola Quensland
Authors: Smith GC
Published: June 2005

In a mark-recapture study of small mammals, 92 female and 59 male AntechinusfIavipes were caught on
Kinaba I. during 13 803 trap-nights and 8887 trap-days. A.flavipes mated almost synchronously in late
August-early September each year. Young born in early October were carried in the pouch for
approximately 36 days, cared for in the nest for a further 2-3 months and weaned through January. All
males died within approximately 1 month of mating. Other causes of mortality included winter
mortality, post-reproductive mortality amongst breeding females, and juvenile mortality after weaning;
these types of population mortality were not severe. In one breeding season (1977-78), a proportion of
females failed to give birth; with pouch mortality, significantly fewer young were weaned per female
from this season than from others (1976-77, 1978-79). This was compensated for by greater
post-weaning survival of young, so that demographic fluctuations and size of the trapped population did
not differ appreciably between years. Young A.flavipes remained near to their place of birth for
approximately 5 months after weaning. After this males dispersed further than did females. The timing
of breeding for A.flavipes at Kinaba I. is discussed in relation to that of other Antechinus populations in
eastern Australia. Timing of breeding is believed to be principally related to climatic factors.
Tree Species Selection by Free-Ranging Koala Populations in Victoria.
Authors: Hindell MA , Handasyde KA , Lee AK
Published: June 2005

Tree species selection was studied in free-ranging populations of koalas [Phascolarctos cinereus] on Phillip Island and the Brisbane Ranges in Victoria. At both sites koalas were found mainly on Eucalyptus spp. but occasionally used Acacia spp. Although koalas occurred on most of the Eucalyptus spp. present, both populations showed preferences for one or two species, particularly E. viminalis. Individual koalas showed different preferences, but the majority preferred E. viminalis. Some occurred exclusively on other species even when E. viminalis was close by. Koalas also showed preference for individual trees within a species.
The European Rabbit in South-Western Australia. III. Survival.
Authors: Wheeler SH , King DR
Published: June 2005

The survival of Oryctolagus cuniculus was investigated at 2 sites in the southern part of Western Australia using live-trapping. Winter myxomatosis appears to have been a major factor in determining the changes in population size, through its effect on the survival of young rabbits.
Susceptibility of Australian Feral Mice to Ectromelia Virus
Authors: Roberts JA
Published: June 2005

Feral mice from western Victoria, the Murrumbidgee Irrigation Area and the Northern Tablelands of New
South Wales, and the Darling Downs of south Queensland, have been infected with ectromelia virus in a
laboratory. There is no evidence that the virus is endemic in the feral mice. The infectivity of ectromelia
is similar in all groups of feral mice, and in laboratory mice. The lethality of the infection is high in the Victorian
mice, whereas mice from the other regions have moderate to high levels of innate resistance. Possible
consequences of the release of ectromelia, to prevent or terminate mouse plagues, are discussed.
A Technique for Estimating the Numbers of Eastern Gray Kangaroos, Macropus-Giganteus, Grazing a Given Area of Pasture
Authors: Perry RJ , Braysher ML
Published: June 2005

This paper outlines a technique for estimating, by means of faecal pellet counts, the absolute number
of eastern grey kangaroos, Macropus giganteus, grazing on a given area in the A.C.T. Absolute numbers
were obtained by comparing relative density of pellets on the area to be assessed, with pellet density
in the grey kangaroo enclosure at Tidbinbilla Nature Reserve, which has a known area and a known
kangaroo population. The decay rate of pellets in three different areas did not vary significantly.
The average number of pellets per pellet group was similar in all three areas, but during drought kangaroos
tended to drop fewer pellets per group. However, the potential error caused by this can be avoided if
the control and test areas are assessed at the same time. The problem of defining a group is eliminated
by counting individual pellets rather than groups.
Effects of logging and fire on small mammals in Mumbulla State Forest, near Bega, New South Wales
Authors: Lunney D. , Cullis B. , Eby P.
Published: June 2005

This study of the effects of logging on small mammals in Mumbulla State Forest on the south coast of New South Wales included the effects of a fire in November 1980 and a drought throughout the study period from June 1980 to June 1983. Rattus fuscipes was sensitive to change: logging had a significant impact on its numbers, response to ground cover, and recapture rate; fire had a more severe effect, and drought retarded the post-fire recovery of the population. The three species of dasyurid marsupials differed markedly in their response to ground cover, canopy cover, logging and fire. Antechinus stuartii was distributed evenly through all habitats and was not affected by logging, but fire had an immediate and adverse effect which was sustained by the intense drought. A. swainsonii markedly preferred the regenerating forest, and was not seen again after the fire, the failure of the population being attributed to its dependence on dense ground cover. Sminthopsis leucopus was found in low numbers, appeared to prefer forest with sparse ground cover, and showed no immediate response to logging or fire; its disappearance by the third year post-fire suggests that regenerating forest is inimical to the survival of this species. Mus musculus showed no response to logging. In the first year following the fire its numbers were still very low, but in the next year there was a short-lived plague which coincided with the only respite in the 3-year drought and, importantly, occurred in the intensely burnt parts of the forest. The options for managing this forest for the conservation of small mammals include minimising fire, retaining unlogged forest, extending the time over which alternate coupes are logged and minimising disturbance from heavy machinery.
Den Sites of Possums, Trichosurus-Vulpecula, and Frequency of Use in Mixed Hardwood Forest in Westland, New-Zealand
Authors: Green WQ , Coleman JD
Published: June 2005

Forty-seven common brushtail possums, Trichosurus vulpecula, were radiotracked to 282 dens on 546
occasions. Just over half of all dens were in living trees; the remainder were evenly distributed between
dead standing stems (including short stumps) and logs, with a few (3%) in banks and rock fissures.
Of all the den entrances, 73% were at, or below, ground level amongst root systems or in logs.
Although dead standing stems (over 25 cm d.b.h.) made up only 4% of standing stems in forest below
500 m altitude, they contained 41% of the dens. Each possum probably used between 10 and 15 dens
each year. There were no differences in den choice and frequency of use between mature males and
females. Den choice by matures and immatures was similar, but mature possums used dens in 'dead'
sites more than did immatures. The implications of dens in the transmission of bovine tuberculosis are
discussed.
The Estrous-Cycle Length of the Bandicoot Isoodon-Macrourus
Authors: Gemmell RT
Published: June 2005

The length of the oestrous cycle of the bandicoot Isoodon macrourus was determined. Pouch young were
removed from lactating bandicoots at day 30 of lactation and the mothers were subsequently housed in
enclosures without males (for oestrous cycle) and with males (for pregnancy). Births were observed 32-48 d
after removal of young. The period of removal of young until ovulation was shown to be 6 d, the gestation
length was known to be 12.5 d and the length of an oestrous cycle was calculated to be 22.1 � 1.6 d
(mean � s.e., N=10), with a range of 14-30 d.
Assessment of an Approximate Lethal Dose Technique for Determining the Relative Susceptibility of Non-Target Species to 1080-Toxin
Authors: Calver MC , Mcilroy JC , King DR , Bradley JS , Gardner JL
Published: June 2005

The susceptibility of eight species of dasyurid marsupials and five species of murid rodents from
the pastoral areas of Western Australia to the toxin sodium monofluoroacetate (Compound 1080) was
assessed. Both LD*5O tests and an increasing dose procedure to determine the approximate lethal dose
(ALD) were used. The results ranged from a low ALD of 1.6 mg kg-1 for an island population of
Pseudomys hermannsburgensis to a high of 20 mg kg-1 for a mainland population of Notomys
mitchelli. Intraspecific and regional variation in sensitivity was evident: three populations of P.
hermannsburgensis showed widely different ALDS, and high ALDS were found in the Millstream area
relative to elsewhere in the pastoral regions. Where both ALD and LD*5O were available, the dose response
curve was steep; all LDSOS were less than a factor of 1.5 above the ALD. LD*5O values and ALDS were
significantly correlated for selected dasyurids and murids, using published data. A computer simulation
based on sampling a standard number of animals from 10 theoretical populations differing only in their
LD~O confirmed that ALD and LD*5O gave similar rankings of sensitivity, although high variance on
the LD~O reduced the strength of the correlation. Actual dosing data from eight populations of Rattus
fuscipes were also analysed; both LD*5O and ALD gave similar rankings of population sensitivity. Subject
to assumptions about the variability of sensitivity within a population, the ALD offers an alternative to
LD~O testing that requires fewer animals, and need not cause more than one death per population tested.
Denning Habits of Common Brushtail Possums, Trichosurus Vulpecula, in New Zealand Lowland Forest.
Authors: Cowan PE
Published: June 2005

Fifty-five T. vulpecula were radio-tracked to 182 den sites on 1987 occasions in the podocarp and mixed hardwood forest of the Orongorongo Valley, near Wellington. Most dens (92%) were above ground in trees, particularly in large trees with many clumps of perching epiphytes; the remainder were under fallen logs or trees or in dense tangles of gorse. Melicytus ramiflorus was the most commonly used living tree species. Others used commonly were Knightia excelsa, Elaeocarpus dentatus, Laurelia novaezealandiae [L. novae-zelandiae] and Podocarpus totara. Use was not dictated solely by availability. Trees without perching epiphytes were hardly ever used. Each possum used 11-15 den trees/yr, most only occasionally; the 3 most commonly used den trees accounted for 60-75% of observations. Males used more dens than females, and the sexes differed in their frequencies of the use of the various tree species, though not in the species used. Possums changed dens frequently, on average 2 nights in 3. Den sharing was uncommon, but many dens, including those on the ground, were used sequentially by several (up to 9) different possums. Dens on the ground were used mostly in autumn and winter, by possums in poor condition or after prolonged heavy rain. The implications of den site choice and use by possums are discussed, particularly in relation to den sites as a limiting resource, and the role of dens in the transmission of bovine tuberculosis. There was about a 50% chance that a den would be occupied by different possums within the probable survival period of deposited tuberculosis bacilli.
Seasonal Distribution and Abundance of Dugongs in the Western-Gulf-of-Carpentaria
Authors: Bayliss P , Freeland WJ
Published: June 2005

Aerial surveys of coastal waters (27 216 km2) in the western Gulf of Carpentaria during the dry season
of 1984 and wet season of 1985 indicated no major seasonal changes in distribution and relative
abundance of dugongs. Minimum population size in the dry season was estimated as 16 816 � 2946
(standard error), with a relative density of 0.62 k 0.11 km-2, and that for the wet season 16 846 + 3257,
with a relative density of 0.62 � 0.12 km-2. The estimates exclude 5% of observations which could
have been either dugongs or Irrawaddy dolphins, and were corrected for submerged dugongs and those
missed on the surface. Dugongs were unevenly distributed over the study area, and neither mean group
size nor proportion of calves varied between seasons. Dugong abundance was correlated with area of
available seagrass. The catch rate of dugongs by Aboriginal people off Numbulwar decreased six-fold
between the 1960s and 1985 (60 to 10 p.a.), possibly due to excessive hunting.
Water and Energy-Metabolism and Estimated Food-Consumption Rates of Free-Living Wambengers, Phascogale-Calura (Marsupialia, Dasyuridae)
Authors: Green B , King D , Bradley a
Published: June 2005

The metabolic rates and water fluxes of free-living Phascogale calura were determined with doubly
labelled water. The highest rates of water influx occurred in October, when the adult population
consisted of lactating females only. The highest metabolic rates occurred in June, and the lowest rates
of both water influx and metabolism occurred in March. The value of the data in designing toxic baits
for the control of foxes or other exotic pests, while minimising the hazard to phascogales of accidental
poisoning, is discussed.
Altitudinal and Seasonal Differences in the Diets of Antechinus-Swainsonii and Antechinus-Stuartii (Marsupialia, Dasyuridae) in Relation to the Availability of Prey in the Snowy Mountains
Authors: Green K
Published: June 2005

The diets of Antechinus stuartii and A. swainsonii and the availability of their prey were studied in
the Snowy Mountains in areas subjected to a winter cover of snow. Active prey were found to be less
common in winter than summer and less common at higher than lower altitudes. The prey taken were
more likely to reflect availability (as measured either by pitfall traps or litter samples) where prey was
scarce. The diet varied between years but within years was more variable for A. stuartii than for
A. swainsonii, possibly because A. stuartii was able to feed in trees in summer but not in winter,
whereas A. swainsonii foraged only on the ground in all seasons.
Antechinus stuartii and A. swainsonii fed on different types of prey at low subalpine altitudes
(1600 m), where they foraged in different microhabitats; this difference was also reflected in the sizes
of prey consumed. At high subalpine altitudes (1850 m), A. stuartii and A. swainsonii fed on both
the same type and the same size of prey, indicating that the two species did not select different prey
sizes but that prey size was determined by the size of food available to each species. Predation on a
particular group by A. swainsonii in summer was more likely if that prey group was also available
in winter. This suggests that by improving its skills at finding and catching these prey, A. swainsonii
was better fitted for survival through the winter. This may help explain the greater abundance of
A. swainsonii and the decline in numbers of A. stuartii almost to local extinction in snow-covered
areas.
Mouse Plagues in South Australian Cereal-Growing Areas. Ii. An Empirical Model for Prediction of Plagues.
Authors: Mutze GJ , Veitch LG , Miller RB
Published: June 2005

A model for predicting the occurrence of mouse plagues is presented based on rainfall and crop yield. The model shows that the probability of a plague occurring in the following autumn is raised if: grain yield in the current season is high but was low 2 years previously; autumn rainfall in the current year is high; and Nov. rainfall is high and Oct. rainfall is low in the current year. The model was developed using logistic regression analysis of data from 6 sites and tested using independent data from a further 6 sites. Using all data, the model accounts for 41% of the deviance in plague occurrences. Hypotheses proposed by previous authors attributing the occurrence of mouse plagues to good cropping seasons, unusually high autumn rainfall and prior drought are mostly supported. Spring rain is a previously unrecognized contributing factor. Possible application of the model for preventive control of mouse damage is discussed.
Home Range and Activity of the Broad-toothed Rat, Mastacomys fuscus, in Subalpine Heathland
Authors: Bubela TM , Happold DCD , Broome LS
Published: June 2005

Radiotelemetry and trapping were used to examine the home range and activity of Mastacomysfuscus
Thomas in subalpine heathland at Smiggin Holes, N.S.W. The 75% utilisation contour was used to
represent the home range. Its size varied between sexes and between seasons. During the mid-breeding
season (January) male home ranges were larger than those of females. In late summer and autumn
home ranges of males decreased and were no longer significantly larger than those of females. There
was no significant variation in home ranges of females from January to autumn, although there
was a slightly decreasing trend. In winter, individuals of both sexes congregated into communal nests,
and home range decreased dramatically. Seasonal variation in home range is explained in terms of the
social behaviour of the species. M. fuscus was mainly nocturnal but also exhibited some diurnal
activity. There was no variation in activity between the sexes. Individuals were most active in January
and February, became less active in March and late autumn, and were least active in winter.
Immobilisation of Crabeater Seals, Lobodon Carcinophagus, With Ketamine and Diazepam.
Authors: Shaughnessy PD
Published: June 2005

The anaesthetic ketamine hydrochloride and the tranquilizer diazepam (valium) were used to immobilize ten wild adult crabeater seals for studies of breeding biology and lactation carried out on pack-ice off the coast of Enderby Land, Antarctica, in the spring of 1985. In seventeen trials dose rates averaged 6.0 mg/kg ketamine and 0.2 mg/kg diazepam. Repeat treatments were 4-7 days apart. Time to handling was 20-40 min. Muscle tremors were alleviated with diazepam. One animal died after receiving low doses and showing signs of recovery. The suspected cause of death was asphyxiation caused by frozen exhalations on a canvas bag held over its head. No other adverse reactions were observed.
Defluorination of Sodium Monofluoroacetate (1080) by Microorganisms Found in Bait Materials.
Authors: Wong DH , Kirkpatrick WE , Kinnear JE , King DR
Published: June 2005

A range of bait materials (kangaroo and horse meat, beff, crackle, egg and oats) was used during pest control programmes that utilized sodium monofluoroacetate (1080 poison). These materials were assayed for the presence of microorganisms (fungi and bacteria) and the ability of these microorganisms to defluorinate 1080 was investigated. In general, the defluorinating activity was low when 1080 was the sole carbon source, but in the presence of an alternative carbon source (e.g. peptone-meat extract) the defluorinating ability of many organisms was greatly enhanced. The extent of defluorination varied among the different types of organisms associated with the baits. Microorganisms isolated from oats and kangaroo meat showed the highest defluorinating activity, whereas those associated with crackle and egg had the lowest. Of the isolates tested only Fusarium oxysporum exhibited high defluorinating ability in soil, defluorinating approx equal to 72% of the available 1080 (20mM) in 15 d at 27 deg C. The implications of these findings for predator/pest control are discussed.
Field Immobilisation of Tasmanian Devils (Sarcophilus Harrisii) With Ketamine Hydrochloride and Xylazine Hydrocholoride.
Authors: Pemberton D , Gales N
Published: June 2005

A combination of the dissociative anaesthetic ketamine hydrochloride and the sedative xylazine hydrochloride was used on 17 Tasmanian devils, and ketamine hydrochloride only on a further 4 animals, in the field. A dosage of 4-5 mg ketamine hydrochloride per kg body weight and 0.4-0.8 mg xylazine hydrochloride per kg body weight, administered via an intramuscular injection, resulted in short induction times (2-10 min), short recovery times (15-63 min) and 88% of the animals being unable to resist handling. The ease with which drugs were injected, and the apparent lack of adverse reactions by the devils, make this form of chemical restraint appropriate for use in the field.
Abundance estimates of small mammals in Australian tropical rainforest: a comparison of four trapping methods
Authors: Laurance WF
Published: June 2005

I compared the efficacy of terrestrial, arboreal, carnivore, and pitfall trapping methods for censusing
small (200 animals per 1000 trap-nights), whereas carnivore (83.7 animals per
1000 trap-nights) and pitfall (9.1 animals per 1000 trap-nights) traps were less effective. However, each
method was particularly effective for 1-4 species, with factors such as diet, vertical microhabitat
use, body size and trap avoidance strongly influencing trappability of different species. Strategies for
censusing small mammals in tropical rainforest are discussed.
Predictions of the impacts of changes in population size and environmental variablitity on Leadbeater's possum, Gymnobelideus leadbeateri McCoy (Marsupialia: Petauridae) using population viability analysis: an application of the computer program VORTEX.
Authors: Lindenmayer DB , Lacy RC , Thomas VC , Clark TW
Published: June 2005

Population Viability Analysis (PVA) uses computer modelling to simulate interacting deterministic and
stochastic factors (e.g. demographic, genetic, spatial, environmental and catastrophic processes) that
act on small populations and assess their long-term vulnerability to extinction. The computer program
VORTEX was used in a PVA of Leadbeater's possum, Gymnobelideus leadbeateri McCoy, an endangered
arboreal marsupial that is restricted to the montane ash forests of the central highlands of Victoria.
PVA was used to examine the impacts of changes in the size of subpopulations and the effects of
environmental variation. Our analyses demonstrated that an annual linear decline in the carrying
capacity in all or parts of the habitat will lead to the extinction of G. leadbeateri in those areas.
Mean time to extinction was related to the rate of annual decrease. This conclusion is of practical and
management importance as there is presently a decline in suitable habitat because of an annual loss of
more than 3.5% of trees with hollows, which provide nest sites for G. leadbeateri. Because nest sites
are a factor that limits populations of G. leadbeateri, the species could be lost from large areas within
the next 50 years. PVA was also used to determine the viability of populations in areas, such as oldgrowth
forest, where there is not likely to be a steady decline in habitat carrying capacity resulting from
the loss of trees with hollows. This allowed an analysis of the cumulative impacts of small population
size, environmental variation and genetic factors, which showed that, for a 100-year projection,
simulated populations of 200 animals or more remained demographically stable and experienced a less
than 10% decline in predicted genetic variability. However, the relatively simplified nature of population
modelling and the suite of assumptions that underpin VORTEX mean that the probability of extinction
of populations of this size may be greater than determined in this study. As a result, it is possible that
only populations of more than 200 animals may persist in the long term where suitable habitat can be
conserved or established and subsequently maintained without a reduction in carrying capacity.
The Influence of population density and habitat on grouping in the western grey kangaroo, Macropus fuliginosus
Authors: Coulson G
Published: June 2005

Population density and habitat structure have been identified as influencing grouping patterns in
kangaroos, but the separate contributions of each factor have rarely been distinguished. Grouping was
examined in the western grey kangaroo, Macropus fuliginosus, at Hattah-Kulkyne National Park,
north-western Victoria, where the population exhibits marked changes in density throughout habitats
that provide a range of cover. Group size and population density in each habitat were surveyed at two
times of day and at roughly 2-monthly intervals from March 1983 until December 1985. Of the four
major habitats, mallee and woodland offered moderate cover, whereas grassland and lake bed gave
sparse cover. Visibility of kangaroo groups was highest in the sparse habitats, and was positively related
to the size of the group, at least in the lower range of group sizes. At densities up to 40km-2,
groups that formed in the sparse habitats were larger than the groups in the two habitats that offered
moderate cover. Three habitats (lake bed, grassland and woodland) had more smaller and more larger
groups than expected if group formation was a random process. Large males were seen alone more
often than expected by chance in lake bed, and less often in moderate cover; females with young-atfoot
were over-represented as singletons in all four habitats. The size and composition of groups
recorded in this study suggest that the basic components of the social organisation of kangaroos are
best discerned in habitats that carry a low population density, but that also provide the most cover.