The Effect of Temporary Closure of Watering Points on Grazing Intensity of Red and Grey Kangaroos With Related Observations on Feral Goats.

1997 ◽  
Vol 19 (2) ◽  
pp. 157 ◽  
Author(s):  
D Freudenberger ◽  
RB Hacker
Keyword(s):  
Grazing Intensity ◽  
Grazing Pressure ◽  
Red Kangaroo ◽  
Goat Grazing ◽  
Grey Kangaroo ◽  
Eastern Australia ◽  
Arid Rangelands ◽  
A Minor ◽  
Temporary Closure ◽  
Feral Goat

In this study we examined the utility of manipulating artificial waters as a means of managing total grazing pressure in semi-arid rangelands of eastern Australia. We tested the efficacy of 'Finlayson trough' exclosure technology at three locations, over two summers, in paddocks with red kangaroos (Macropus rufirs) and two species of grey kangaroo (M. giganteus and M. fuliginosus). We also examined the effect of closing off five waters on the distribution of feral goat grazing intensity at one study site. Generally, there were no apparent reductions in kangaroo and goat grazing intensity following 6-10 weeks of water exclosure, the exception being a minor reduction in red kangaroo grazing intensity at one location. We concluded that kangaroo and goat grazing pressure cannot be substantially reduced by simply closing off waters in and near paddocks for several months. Key words: kangaroos, water exclosure. feral goats, grazing pressure, paddock spelling

Water metabolism and renal function and structure in eastern grey kangaroos (Macropus giganteus): responses to water deprivation

2000 ◽  
Vol 48 (4) ◽  
pp. 335 ◽  
Author(s):  
C. E. Blaney ◽  
T. J. Dawson ◽  
H. C. K. McCarron ◽  
R. Buffenstein ◽  
A. K. Krockenberger
Keyword(s):  
Kidney Function ◽  
Arid Zone ◽  
Water Restriction ◽  
Water Metabolism ◽  
The Past ◽  
Red Kangaroo ◽  
Grey Kangaroo ◽  
Additional Water ◽  
Urine Concentrations ◽  
Arid Rangelands

The eastern grey kangaroo (M. giganteus) is usually found in mesic habitats but in the past 30–40 years it has expanded its range into arid rangelands. A suggested reason for this expansion has been the provision of additional water sites for domestic stock. In this study we examined aspects of kidney function and water metabolism of M. giganteus. This was done during normal hydration and water restriction so that the water-conserving abilities of M. giganteus could be compared with those of the red kangaroo (M. rufus), the habitat of which is arid rangelands and desert. The indices relative medullary thickness (RMT) and medullary to cortical ratio, derived from the morphology of the kidney, are indicators of renal concentrating ability. In M. giganteus both these indices were lower than in M. rufus: the RMT was 5.24 0.15 (mean s.e.) for M. giganteus and 6.00 0.10 for M. rufus. Measured maximal urine concentrations of these species were 2444 59 (M. giganteus) and 3135 165 mosmol kg–1 (M. rufus), with the respective maximum individual concentrations being 2752 and 4054 mosmol kg–1. Kidney function in hydrated and dehydrated M. giganteus was assessed via glomerular filtration rate, urine flow rate and concentration index. As measured by these parameters, M. giganteus had renal water-conserving capacities similar to, or superior to, those of many comparable-sized arid-zone-inhabiting placental mammals, but below those of M. rufus. Water metabolism, as measured by water turnover, showed a similar pattern.

Distribution and Relative Abundance of Feral Goats in the Rangelands of Eastern Australia.

1993 ◽  
Vol 15 (2) ◽  
pp. 331 ◽  
Author(s):  
C Southwell ◽  
K Weaver ◽  
N Sheppard ◽  
P Morris
Keyword(s):  
Relative Abundance ◽  
New South ◽  
New South Wales ◽  
Aerial Survey ◽  
South Wales ◽  
Eastern Australia ◽  
Goat Population ◽  
Arid Rangelands ◽  
Feral Goat ◽  
Semi Arid

An aerial survey of 966,000 km2 of the arid/semi-arid rangelands of Queensland and New South Wales in the winter of 1992 indicated a minimum feral goat population of almost 1 million animals (density 0.97�0.12/km2). Observed density (f standard error) was higher in New South Wales (1.51�0.23/km2) than in Queensland (0.47�0.09/km2).

scholarly journals Does EO NDVI seasonal metrics capture variations in species composition and biomass due to grazing in semi-arid grassland savannas?

2015 ◽  
Vol 12 (14) ◽  
pp. 4407-4419 ◽  
Author(s):  
J. L. Olsen ◽  
S. Miehe ◽  
P. Ceccato ◽  
R. Fensholt
Keyword(s):  
Time Series ◽  
Species Composition ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Regional Scale ◽  
Grazing Intensity ◽  
Test Site ◽  
Grazing Pressure ◽  
Modis Ndvi ◽  
Coarse Resolution

Abstract. Most regional scale studies of vegetation in the Sahel have been based on Earth observation (EO) imagery due to the limited number of sites providing continuous and long term in situ meteorological and vegetation measurements. From a long time series of coarse resolution normalized difference vegetation index (NDVI) data a greening of the Sahel since the 1980s has been identified. However, it is poorly understood how commonly applied remote sensing techniques reflect the influence of extensive grazing (and changes in grazing pressure) on natural rangeland vegetation. This paper analyses the time series of Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI metrics by comparing it with data from the Widou Thiengoly test site in northern Senegal. Field data include grazing intensity, end of season standing biomass (ESSB) and species composition from sizeable areas suitable for comparison with moderate – coarse resolution satellite imagery. It is shown that sampling plots excluded from grazing have a different species composition characterized by a longer growth cycle as compared to plots under controlled grazing or communal grazing. Also substantially higher ESSB is observed for grazing exclosures as compared to grazed areas, substantially exceeding the amount of biomass expected to be ingested by livestock for this area. The seasonal integrated NDVI (NDVI small integral; capturing only the signal inherent to the growing season recurrent vegetation), derived using absolute thresholds to estimate start and end of growing seasons, is identified as the metric most strongly related to ESSB for all grazing regimes. However plot-pixel comparisons demonstrate how the NDVI/ESSB relationship changes due to grazing-induced variation in annual plant species composition and the NDVI values for grazed plots are only slightly lower than the values observed for the ungrazed plots. Hence, average ESSB in ungrazed plots since 2000 was 0.93 t ha−1, compared to 0.51 t ha−1 for plots subjected to controlled grazing and 0.49 t ha−1 for communally grazed plots, but the average integrated NDVI values for the same period were 1.56, 1.49, and 1.45 for ungrazed, controlled and communal, respectively, i.e. a much smaller difference. This indicates that a grazing-induced development towards less ESSB and shorter-cycled annual plants with reduced ability to turn additional water in wet years into biomass is not adequately captured by seasonal NDVI metrics.

Field metabolic rate and water turnover of red kangaroos and sheep in an arid rangeland: an empirically derived dry-sheep-equivalent for kangaroos

2009 ◽  
Vol 57 (1) ◽  
pp. 23 ◽  
Author(s):  
A. J. Munn ◽  
T. J. Dawson ◽  
S. R. McLeod ◽  
D. B. Croft ◽  
M. B. Thompson ◽  
...  
Keyword(s):  
Metabolic Rate ◽  
Grazing Pressure ◽  
Ovis Aries ◽  
Domestic Sheep ◽  
Detailed Knowledge ◽  
Water Turnover ◽  
Field Metabolic Rate ◽  
Red Kangaroo ◽  
Resource Requirements ◽  
Comparative Measure

Sustainable management of pastures requires detailed knowledge of total grazing pressure, but this information is critically lacking in Australia’s rangelands where livestock co-occur with large herbivorous marsupials. We present the first comparative measure of the field metabolic rate (an index of food requirement) of Australia’s largest marsupial, the red kangaroo (Macropus rufus), with that of domestic sheep (Ovis aries; merino breed). We tested the assumption that the grazing pressure of red kangaroos is equivalent to 0.7 sheep, and show this to be a two-fold overestimation of their contribution to total grazing. Moreover, kangaroos had extraordinarily lower rates of water turnover, being only 13% that of sheep. Consequently, our data support arguments that the removal of kangaroos may not markedly improve rangeland capacity for domestic stock. Furthermore, given the low resource requirements of kangaroos, their use in consumptive and non-consumptive enterprises can provide additional benefits for Australia’s rangelands than may occur under traditional rangeland practices.

An extension to the known range of the eastern grey kangaroo Macropus giganteus on Cape York Peninsula.

2005 ◽  
Vol 27 (2) ◽  
pp. 225 ◽  
Author(s):  
EG Ritchie
Keyword(s):  
Arid Regions ◽  
Grey Kangaroo ◽  
Eastern Australia ◽  
Northern Cape ◽  
Cape York ◽  
Open Forests ◽  
Semi Arid

THE eastern grey kangaroo (Macropus giganteus) is one of Australia?s widest-ranging large macropodids, occurring in open forests, woodlands, subalpine woodland, farmland, and semi-arid regions throughout most of eastern Australia (Menkhorst and Knight 2001). However current general accounts (e.g., Poole 1995, Menkhorst and Knight 2001) regard M. giganteus as being absent from the northern Cape York Peninsula.

scholarly journals Soil Properties and Plant Community Changes along a Goat Grazing Intensity Gradient in an Open Canopy Oak Forest

2013 ◽  
Vol 41 (2) ◽  
pp. 567 ◽  
Author(s):  
Aimilia LEMPESI ◽  
Apostolos P. KYRIAZOPOULOS ◽  
Michail ORFANOUDAKIS ◽  
Georgios KORAKIS
Keyword(s):  
Soil Properties ◽  
Plant Community ◽  
Management Practices ◽  
Plant Cover ◽  
Grazing Intensity ◽  
Oak Forest ◽  
Goat Grazing ◽  
Open Canopy ◽  
Grazing Intensities ◽  
Soil Measurements

Understanding how the management practices of silvopastoral systems affect the long-term sustainability of oak ecosystems and what their influence is on nutrient cycling and plant community, is of great interest. The aim of this study was to examine the effects of relative grazing intensity on soil properties and on vegetation characteristics in an open canopy oak forest dominated by Quercus frainetto. The research was conducted in the area of Pentalofos, which is located in Evros region, north-eastern Greece and is grazed by goats. The distance from a goat corral was used to represent relative grazing intensity. In June 2011, soil and vegetation samples were collected along transects placed at 50, 150, 300, 600 and 1200 m from the goat corral, running perpendicular to three replicates. Soil measurements included pH, phosphorous (P) and nitrogen (N) concentrations while vegetation measurements included plant cover, species composition and diversity. Plant cover was not significantly different among grazing intensities. Species diversity, especially of the woody vegetation layer, was significantly higher in the light grazing intensity in comparison to both the heavy and the very light grazing. Heavy grazing reduced soil organic matter while it increased total nitrogen. Grazing intensity did not affect available P and soil pH. Light to moderate goat grazing could ameliorate floristic diversity and increase sustainability of oak forests in the Mediterranean region.

The ontogeny of the pancreas in macropodid marsupials

1978 ◽  
Vol 26 (3) ◽  
pp. 487
Author(s):  
AW White ◽  
CJF Harrop
Keyword(s):  
Connective Tissue ◽  
Relative Size ◽  
Pancreatic Tissue ◽  
Pancreatic Development ◽  
Endocrine Tissue ◽  
Red Kangaroo ◽  
Slow Development ◽  
Grey Kangaroo ◽  
Insulin Secreting Cells ◽  
Acinar Tissue

The development of the endocrine pancreas in kangaroos was examined histologically with tissue from three kangaroo species, the red kangaroo Megaleia rufa, the euro Macropus robustus erubescens, and the grey kangaroo Macropus giganteus. The relative size of the pancreas of the pouch young was found not to differ significantly from that of adults. Stages of pancreatic development were described from the frequency of the occurrence of the pancreatic epithelial ducts and the B or insulin-secreting cells, while the development and distribution of the A2 or glucagon-producing cells was also observed. In pouch young of less than 22 days of age the pancreas is dominated by ductular epithelial and undifferentiated pancreatic cells. From days 42 to 97 of pouch life B endocrine cells tend to be concentrated together and ductular tissue encroaches into areas previously dominated by connective tissue. After 120-135 days the first A2 cells are apparent and are usually located at the periphery of the islets, which now take on a distinctive appearance as the acinar tissue expands and separates them. After 135 days of pouch life A2 cells outnumber B cells; the endocrine tissue assumes an adult appearance after 150-160 days. The major difference between the development of pancreatic tissue in foetal sheep and pouch-young kangaroo is the prolonged dominance of connective tissue and the slow development of endocrine tissue in the former.

Rangeland condition in relation to environmental variables, grazing intensity and livestock owners' perceptions in semi-arid rangeland in western Iran

2010 ◽  
Vol 32 (4) ◽  
pp. 367 ◽  
Author(s):  
M. Faramarzi ◽  
S. Kesting ◽  
J. Isselstein ◽  
N. Wrage
Keyword(s):  
Environmental Variables ◽  
Management Practices ◽  
Grazing Intensity ◽  
Bare Soil ◽  
Grazing Pressure ◽  
Botanical Composition ◽  
Western Iran ◽  
Range Condition ◽  
Rangeland Condition ◽  
Semi Arid

Rangeland condition has often been assessed in relation to either botanical, edaphic, environmental or management factors. In this investigation, we analysed the interaction of soil and topographic variables, management and range condition against the background of a sociological survey of livestock owners in western Iran to better understand the main influencing factors of rangeland quality in the area. In four grazing areas in Kermanshah differing in grazing pressure, environmental variables and livestock owners’ perceptions on range condition, investigations of botanical composition, soil and topographic variables were carried out on 43 main plots. To evaluate range condition, four factors were considered, namely litter frequency, herbage palatability, amount of biomass, and percentage of bare soil. A questionnaire was used to obtain information about management practices, the perception of livestock owners on range condition and suggested solutions to problems in the different grazing areas. The range condition scores showed that the condition of the sites was either fair or poor. Of the soil and topographic factors, only north-facing aspect explained part of the variation in range condition scores. High grazing intensity was associated with poor range condition. To improve the rangeland condition, measures influencing water availability and a reduction of grazing pressure seem to be more relevant in the study area than fertilisation or seeding.

Insights on the relationship between total grazing pressure management and sustainable land management: key indicators to verify impacts

2019 ◽  
Vol 41 (6) ◽  
pp. 535 ◽  
Author(s):  
C. M. Waters ◽  
S. E. McDonald ◽  
J. Reseigh ◽  
R. Grant ◽  
D. G. Burnside
Keyword(s):  
Land Management ◽  
Management Practices ◽  
Temporal Trends ◽  
Grazing Intensity ◽  
Grazing Pressure ◽  
Environmental Stewardship ◽  
Grazing Management ◽  
Sustainable Land Management ◽  
Key Indicators ◽  
The Impact

Demonstrating sustainable land management (SLM) requires an understanding of the linkages between grazing management and environmental stewardship. Grazing management practices that incorporate strategic periods of rest are promoted internationally as best practice. However, spatial and temporal trends in unmanaged feral (goat) and native (kangaroo) populations in the southern Australian rangelands can result land managers having, at times, control over less than half the grazing pressure, precluding the ability to rest pastures. Few empirical studies have examined the impacts of total grazing pressure (TGP) on biodiversity and resource condition, while the inability to manage grazing intensity at critical times may result in negative impacts on ground cover, changes in pasture species composition, increased rates of soil loss and reduce the ability for soils to store carbon. The widespread adoption of TGP control through exclusion fencing in the southern Australian rangelands has created unprecedented opportunities to manage total grazing pressure, although there is little direct evidence that this infrastructure leads to more sustainable land management. Here we identify several key indicators that are either outcome- or activity-based that could serve as a basis for verification of the impacts of TGP management. Since TGP is the basic determinant of the impact of herbivory on vegetation it follows that the ability for rangeland pastoral management to demonstrate SLM and environmental stewardship will rely on using evidence-based indicators to support environmental social licence to operate.

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