Feral goats (Capra hircus L.) in the Macleay River gorge system, north-eastern New South Wales, Australia. II. Impacts on rainforest vegetation

2005 ◽  
Vol 32 (2) ◽  
pp. 111
Author(s):  
Philip Pisanu ◽  
Paul Bayne ◽  
Robert Harden ◽  
Ann Eggert
Keyword(s):  
Large Scale ◽  
Plant Density ◽  
Initial Density ◽  
River System ◽  
Capra Hircus ◽  
South Wales ◽  
Species Abundances ◽  
High Conservation ◽  
Scale Experiment ◽  
Feral Goat

The impacts of feral goats in rainforests and thickets of the Macleay River system were studied. Rainforest floristics and diversity and goat browsing were measured over five years in a large-scale experiment with two experimental controls (density <1 goat km–2 and density ~20 goats km–2), and a goat-removal treatment (670-ha exclosure, initial density ~20 goats km–2). Feral goats browsed forb, shrub, tree and vine species. Sites with many goats were browsed at significantly higher levels than sites from which goats were removed and sites where goats occurred at very low density (<1 goat km–2). Contrary to findings in other studies, no plant species declined substantially where goat densities remained high throughout the study. Only the native forb Urtica incisa increased markedly following removal of goats. High goat numbers were not linked to increased exotic species abundances. At the community scale, species richness, diversity and evenness did not vary substantially among treatments in any year, nor did ordinations of sites (multidimensional scaling) reveal any pattern of site similarity between years that could be related to either goat presence or absence. Rainfall may have influenced plant density and masked the effects of feral goats. Rainforests in the region appear to be resilient to browsing under present feral goat densities, probably because goats feed predominantly in adjacent grassy woodlands and forests. However, we recommend a precautionary approach to feral goat management as these rainforests and thickets are of high conservation value.

Lucerne, phalaris, and wallaby grass in short-term pasture phases in two eastern Australian wheatbelt environments. 1. Importance of initial perennial density on their persistence and recruitment, and on the presence of weeds

2007 ◽  
Vol 58 (2) ◽  
pp. 113 ◽  
Author(s):  
B. S. Dear ◽  
J. M. Virgona ◽  
G. A. Sandral ◽  
A. D. Swan ◽  
B. A. Orchard
Keyword(s):  
Plant Density ◽  
Seedling Recruitment ◽  
Initial Density ◽  
Basal Area ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Annual Rainfall ◽  
Curvilinear Relationship ◽  
Initial Population ◽  
South Wales

The influence of initial plant density on the changes in the populations of 3 perennial pasture species, lucerne (Medicago sativa L.), wallaby grass (Austrodanthonia richardsonii (Cashm.) H.P. Linder), and phalaris (Phalaris aquatica L.), over a 3-year pasture phase was examined in the wheatbelt of southern New South Wales. The perennials were sown at 5 rates in combination with subterranean clover (Trifolium subterraneum L.) at 2 locations, Kamarah [430 mm average annual rainfall (a.a.r.)] and Junee (550 mm a.a.r). The range in initial plant populations for lucerne, phalaris, and wallaby grass was 4–74, 8–94, and 2–20 plants/m2, respectively, at Kamarah and 11–120, 9–149, and 6–48 plants/m2 at Junee. When sown at higher densities, the density of lucerne and phalaris declined curvilinearly over the 3 years at both sites. At the 3 lower densities, phalaris populations remained constant at both sites. Lucerne, in contrast, declined over all densities at both sites except at the lowest density at the wetter site (Junee). The rate of decline in lucerne was negatively related (R2 = 0.75) to initial density at Junee, but not at Kamarah. The density of the native grass, wallaby grass, increased with time at both sites through seedling recruitment. The invasion of experimental plots by the summer weed Eragrostis cilianensis (All.) Vign. ex Janchen (stinkgrass) was restricted by lucerne and phalaris, with a negative curvilinear relationship between perennial density and E. cilianensis seedlings in both environments (R2 = 0.65–0.70). In contrast, wallaby grass was ineffective at suppressing E. cilianensis. By the third year, phalaris had significantly higher herbage yields in spring than lucerne and wallaby grass at both sites and phalaris yield was independent of density. Lucerne yields at this time increased with density only at the wetter site (R2 = 0.64), but wallaby grass yields responded to increasing density at both sites (R2 = 0.27–0.59). The experiment demonstrated that establishing higher initial perennial populations of lucerne and phalaris, which did not recruit during the experiment, will result in the maintenance of higher populations over the life of a 3–4 year pasture phase despite proportionally higher rates of plant loss. The size of the initial population was less critical for wallaby grass, which was able to increase in density through recruitment. High initial populations are likely to be an advantage for suppressing weeds in swards of perennial species with limited ability to increase their basal area, such as lucerne and wallaby grass, but will be less beneficial for species such as phalaris, which can compensate by greatly increasing its basal area at lower densities.

Age, Hair Colour, Live Weight and Fertility of Two Samples of Australian Feral Goat, Capra Hircus.

1981 ◽  
Vol 8 (3) ◽  
pp. 549 ◽  
Author(s):  
PJ Holst
Keyword(s):  
New South ◽  
Live Weight ◽  
Carcass Weight ◽  
Capra Hircus ◽  
Corpora Lutea ◽  
Hair Colour ◽  
South Wales ◽  
Two Samples ◽  
Dressing Percentage ◽  
Feral Goat

Feral goats are slaughtered commercially in Australia, and are used in Angora backcrossing programmes. 327 goats from Queensland and 182 from New South Wales were slaughtered at the same abattoir in Mar. and Nov. 1973 resp. For the 2 groups resp., live weight of females averaged 17.93 plus or minus 4.48 to 31.08 plus or minus 5.56 and 24.65 plus or minus 5.77 to 39.20 plus or minus 5.95 kg according to age, live weight of males (excluding fully grown animals) 22.09 plus or minus 3.49 to 34.14 plus or minus 4.63 and 31.03 plus or minus 8.71 to 52.12 plus or minus 6.46 kg, carcass weight of females 9.22 plus or minus 2.54 to 14.95 plus or minus 2.52 and 11.12 plus or minus 2.45 to 17.25 plus or minus 2.49 kg, carcass weight of males 11.09 plus or minus 2.01 to 22.64 plus or minus 3.82 and 14.83 plus or minus 4.47 to 24.80 plus or minus 2.59 kg (excluding fully grown males in the 2nd group), dressing percentage of females 48.1-51.4 and 44.0-45.1, dressing percentage of males (excluding fully grown animals) 49.3-50.2 and 47.6-47.8, percentage of females with corpora lutea 81.8-100 and 50-65.2, number of corpora lutea per cycling female 1.17-2.08 and 1.45-2.00, percentage of females with embryos 18.2-38.5 and 5.9-33.3, and percentage of females with foetuses 7.7-13.6 and 16.7-66.7. Values for the last 4 traits were highest for females with 2, 4 or 6 teeth.

Size and density of a feral goat Capra hircus population in a protected area in the Pyrenees

2013 ◽  
Vol 9 (3) ◽  
Author(s):  
Juan Herrero ◽  
Olatz Fernández ◽  
Carlos Prada ◽  
Alicia García-Serrano
Keyword(s):  
Protected Area ◽  
Capra Hircus ◽  
Feral Goat

scholarly journals Hydrology influences breeding time in the white-throated dipper

BMC Ecology ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Anna L. K. Nilsson ◽  
Thomas Skaugen ◽  
Trond Reitan ◽  
Jan Henning L’Abée-Lund ◽  
Marlène Gamelon ◽  
...  
Keyword(s):  
Climate Change ◽  
River Discharge ◽  
Large Scale ◽  
Time Window ◽  
River System ◽  
Open Water ◽  
Local Conditions ◽  
Environmental Indices ◽  
Groundwater Levels ◽  
Breeding Time

Abstract Background Earlier breeding is one of the strongest responses to global change in birds and is a key factor determining reproductive success. In most studies of climate effects, the focus has been on large-scale environmental indices or temperature averaged over large geographical areas, neglecting that animals are affected by the local conditions in their home ranges. In riverine ecosystems, climate change is altering the flow regime, in addition to changes resulting from the increasing demand for renewable and clean hydropower. Together with increasing temperatures, this can lead to shifts in the time window available for successful breeding of birds associated with the riverine habitat. Here, we investigated specifically how the environmental conditions at the territory level influence timing of breeding in a passerine bird with an aquatic lifestyle, the white-throated dipper Cinclus cinclus. We relate daily river discharge and other important hydrological parameters, to a long-term dataset of breeding phenology (1978–2015) in a natural river system. Results Dippers bred earlier when winter river discharge and groundwater levels in the weeks prior to breeding were high, and when there was little snow in the catchment area. Breeding was also earlier at lower altitudes, although the effect dramatically declined over the period. This suggests that territories at higher altitudes had more open water in winter later in the study period, which permitted early breeding also here. Unexpectedly, the largest effect inducing earlier breeding time was territory river discharge during the winter months and not immediately prior to breeding. The territory river discharge also increased during the study period. Conclusions The observed earlier breeding can thus be interpreted as a response to climate change. Measuring environmental variation at the scale of the territory thus provides detailed information about the interactions between organisms and the abiotic environment.

Elemental composition of mantle tissue granules in Hyridella depressa (Unionida) from the Hawkesbury-Nepean River system, Australia: inferences from catchment chemistry

2000 ◽  
Vol 51 (2) ◽  
pp. 183 ◽  
Author(s):  
Maria Byrne ◽  
Peter A. Vesk
Keyword(s):  
Freshwater Mussel ◽  
River System ◽  
Direct Analysis ◽  
Common Elements ◽  
Mantle Tissue ◽  
South Wales ◽  
The Common ◽  
Australian Freshwater ◽  
River Site

The Australian freshwater mussel Hyridella depressa sequesters elements in calcium phosphate (CaP) granules that form extensive aggregations in its tissues. Elements contained in these granules were determined by X-ray microanalysis of river and lake mussels from the Hawkesbury–Nepean River system, New South Wales. Granules in freeze-substituted mantle tissue were analysed to determine the variation in element profiles in granules among mussels and among sites. For the common elements Ca, P, Fe, Mg and Mn, granule composition reflected catchment lithology and site trophic status and indicated exogenous input. These were most important for differentiation among lake sites and also indicated differences between lake and river mussels. Site differences seen with some common elements in granules from lake mussels correlated with differences in water chemistry. Trace elements, particularly Al, Cu, Zn and Pb, were also important in lake and river site differentiation. The granules play a major role in element dynamics in freshwater mussel tissues and provide a focal structure for direct analysis of element accumulation by these bivalves. The results indicate that characterization of element content of granules in mussel populations would provide valuable insights into animal–element interactions in freshwater systems for ecological and ecotoxicological investigations.

scholarly journals Marsh rabbit mortalities tie pythons to the precipitous decline of mammals in the Everglades

2015 ◽  
Vol 282 (1805) ◽  
pp. 20150120 ◽  
Author(s):  
Robert A. McCleery ◽  
Adia Sovie ◽  
Robert N. Reed ◽  
Mark W. Cunningham ◽  
Margaret E. Hunter ◽  
...  
Keyword(s):  
National Park ◽  
Large Scale ◽  
Ongoing Debate ◽  
Faunal Communities ◽  
Python Molurus ◽  
Scale Experiment ◽  
Precipitous Decline ◽  
Python Molurus Bivittatus ◽  
The Impact ◽  
Ecological Functioning

To address the ongoing debate over the impact of invasive species on native terrestrial wildlife, we conducted a large-scale experiment to test the hypothesis that invasive Burmese pythons ( Python molurus bivittatus ) were a cause of the precipitous decline of mammals in Everglades National Park (ENP). Evidence linking pythons to mammal declines has been indirect and there are reasons to question whether pythons, or any predator, could have caused the precipitous declines seen across a range of mammalian functional groups. Experimentally manipulating marsh rabbits, we found that pythons accounted for 77% of rabbit mortalities within 11 months of their translocation to ENP and that python predation appeared to preclude the persistence of rabbit populations in ENP. On control sites, outside of the park, no rabbits were killed by pythons and 71% of attributable marsh rabbit mortalities were classified as mammal predations. Burmese pythons pose a serious threat to the faunal communities and ecological functioning of the Greater Everglades Ecosystem, which will probably spread as python populations expand their range.

Factors affecting post-fire seedling establishment of selected mallee understorey species

2000 ◽  
Vol 48 (1) ◽  
pp. 59 ◽  
Author(s):  
J. S. Cohn ◽  
R. A. Bradstock
Keyword(s):  
Large Scale ◽  
Prescribed Burning ◽  
New South ◽  
Eucalyptus Species ◽  
Factors Affecting ◽  
Acacia Species ◽  
Introduced Herbivores ◽  
South Wales ◽  
Rabbit Grazing ◽  
Seedling Germination

Factors affecting the survival of post-fire germinants in mallee communities, in central western New South Wales, were examined. Experiments compared the relative effects of native and introduced herbivores (kangaroos, goats, rabbits), after small- and large-scale fires (20–50 and > 10 000 ha, respectively), with particular emphasis on edge effects, seedling clustering, topography and eucalypt canopy presence. The experiments (1985–1997) focused on common understorey species Acacia rigens Cunn. ex Don, A. wilhelmiana F.Muell. and Triodia scariosa N.T.Burb. subsp. scariosa, in mallee dominated by Eucalyptus species. Following a large fire (1985), high spring rainfall and rabbit grazing on A. rigens only, survival of Acacia species and T. scariosa remained relatively high 4 years later (60–70%). After small burns (1987, 1988), low spring rainfall and grazing by rabbits and kangaroos, survival of Acacia species declined to between 0 and 30% of the germinants by the second summer. In most cases, local extinction had occurred within 8 years. After small burns (1988, 1989) and low spring rainfall, the survival of T. scariosa declined to between 0 and 35% of germinants by the second summer (effect of grazing unknown). No consistent effect of edge, topography and eucalypt canopy was found. Survival of clustered Acacia seedlings was between 10 and 20% lower than unclustered seedlings. Given the high frequency of low rainfall and its interaction with grazing, prescribed burning of mallee for wildfire control and nature conservation may require the local elimination of rabbits and a reduction in kangaroo numbers, especially in the first spring and summer following seedling germination.

ASSISTED EMIGRATION AND THE MORAL DILEMMAS OF THE MID-VICTORIAN IMPERIAL STATE

2016 ◽  
Vol 59 (4) ◽  
pp. 1027-1049 ◽  
Author(s):  
PHILIP HARLING
Keyword(s):  
Large Scale ◽  
New South ◽  
Social Engineering ◽  
Moral Dilemmas ◽  
Irish Famine ◽  
Slave Emancipation ◽  
South Wales ◽  
Ethical Controversy ◽  
Plantation Society ◽  
Imperial State

ABSTRACTThis article examines three voyages of the late 1840s to advance the argument that emigration – often treated by its historians as ‘spontaneous’ – actually involved the laissez-faire mid-Victorian imperial state in significant projects of social engineering. The tale of the Virginius exemplifies that state's commitment to taking advantage of the Famine to convert the Irish countryside into an export economy of large-scale graziers. The tale of the Earl Grey exemplifies its commitment to transforming New South Wales into a conspicuously moral colony of free settlers. The tale of the Arabian exemplifies its commitment to saving plantation society in the British Caribbean from the twin threats posed by slave emancipation and free trade in sugar. These voyages also show how the British imperial state's involvement in immigration frequently immersed it in ethical controversy. Its strictly limited response to the Irish Famine contributed to mass death. Its modest effort to create better lives in Australia for a few thousand Irish orphans led to charges that it was dumping immoral paupers on its most promising colonies. Its eagerness to bolster sugar production in the West Indies put ‘liberated’ slaves in danger.

scholarly journals COSMOLOGICAL CONSTRAINTS FOR THE COSMIC DEFECT THEORY

2011 ◽  
Vol 20 (06) ◽  
pp. 1039-1051 ◽  
Author(s):  
NINFA RADICELLA ◽  
MAURO SERENO ◽  
ANGELO TARTAGLIA
Keyword(s):  
Large Scale ◽  
Hubble Constant ◽  
Big Bang ◽  
Nuclear Species ◽  
Type Ia ◽  
Species Abundances ◽  
Age Of The Universe ◽  
Ia Supernovae ◽  
The Big Bang ◽  
The Universe

The cosmic defect theory has been confronted with four observational constraints: primordial nuclear species abundances emerging from the big bang nucleosynthesis; large scale structure formation in the Universe; cosmic microwave background acoustic scale; luminosity distances of type Ia supernovae. The test has been based on a statistical analysis of the a posteriori probabilities for three parameters of the theory. The result has been quite satisfactory and such that the performance of the theory is not distinguishable from that of the ΛCDM theory. The use of the optimal values of the parameters for the calculation of the Hubble constant and the age of the Universe confirms the compatibility of the cosmic defect approach with observations.

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