Megaleia Rufa Research Articles

Cuterebra myiasis in a group of red kangaroos (Megaleia rufa), a Bennett's wallaby (Macropus rufogriseus fruticus), and a Gunther's dik dik (Maloqua guentheri smithi).

A group of four red kangaroos (Megaleia rufa), a Bennett's wallaby (Macropus rufogriseus fruticus), and a Gunther's dik dik (Maloqua guentheri smithi) were presented over a 2-mo period with draining lesions over the thorax or on the lateral aspect of a hind leg. Only one animal exhibited more than one lesion. Physical examinations revealed infections with fly larvae. The parasites were manually removed and identified as Cuterebra spp. All of the affected animals survived, with no apparent side effects.

High mobility group (HMG) proteins in the tammar wallaby macropus eugenii: Quantitative variations between tissues and testis-specific co-extracted proteins

1. 1. Tammar wallaby ( Macropus eugenii, Marsupialia) proteins with similar electrophoretic mobilities to calf non-histone chromosomal proteins HMG 1, 2, 14 and 17 are perchloric acid extracted from whole tissues (liver, kidney, spleen, brain and testis) and purified liver nuclei (using PCA or 0.35 M NaCl). 2. 2. Tammar and calf HMG 1 have similar amino acid compositions. 3. 3. Two testis-specific basic proteins co-extracting with HMG-like proteins from both tammar and red kangaroo ( Megaleia rufa) are found in whole testis, purified testis nuclei, but not epididymis. 4. 4. Tammar HMG 2 separates into two components on both acid urea and SDS gels. The larger, more basic protein, HMG 2b, is relatively abundant in proliferating tissues (testis, spleen).

Immunology of pouch young marsupials. I. Levels of immunoglobulin transferrin and albumin in the blood and milk of euros and wallaroos (hill kangaroos: [formula omitted][formula omitted], marsupialia).

The concentration of total protein, albumin, transferrin, and immunoglobulin G of adult serum, pouch young serum, milk whey and colostrum has been estimated in three species of kangaroos, Macropus robustus , Macropus rufus (= Megaleia rufa ) and Macropus giganteus . No study of this kind has previously been published for any marsupial species. The three individual proteins were antigenically identical in all four kinds of fluid. Colostrum and milk whey are relatively enriched in transferrin but have low levels of immunoglobulin G. Serum concentrations of total protein, albumin and transferrin rise steadily throughout pouch life and attain adult values when the young finally leaves the pouch. Serum concentrations of immunoglobulin G are very low for the first 90–100 days of pouch life, being approximately half of those in milk whey for this period. After this the level rises rapidly and also reaches adult values when the young leaves the pouch. We suggest that in the first 90–100 days the pouch young is largely protected humorally by passive immunity acquired from the mother, and after this it increasingly makes its own responses.

Seasonal Variation in Daily Activity Patterns, Water Relations and Diet of Emus

The pattern of activity of Emus Dromaius novaehollandae in western New South Wales has been examined and contrasted with that of the other large native animals in the area, Red Kangaroos Megaleia rufa and Euros Macropus robustus. A detailed behavioural analysis indicated that Emus were diurnal and speni a large part of theaay feeding in both summer and winter. During hot days in summer they occasionally sheltered among trees from the radiation heat load. The water requirements of adult Emus measured by tritiated water turnover do not appear high but intake may be limited by the size of the simple gut, resulting in a relatively high frequency of drinking, once per day and occasionally twice per day during hot summer conditions. The water use of chicks, especially young chicks, was much greater than that of the adults. Water losses from an incubating bird, however, were one fifth of those of adult birds in similar conditions. The Emus were omnivorous, relying on insects, seed heads, berries and succulent vegetation. The Emus successfully make their living in the arid zone very differently from the marsupials and the basis of this is discussed in relation to recent findings about their physiological adaptations.

Competitive interactions in the dietary preference of kangaroos and sheep, cattle and goats in inland Australia

The trophic ecology of the large macropods (kangaroos and euros) is summarized. Introduction of livestock has generally favoured the build up of numbers of kangaroos in the arid zone. The reasons are discussed. This paper also reviews work in the arid and semi-arid regions of Australia on diet selectivity of sheep, cattle and goats. Comparisons between the diets selected by domestic livestock and the large marsupials (red kangaroo, Megaleia rufa and euro Macropus robustus) are considered in detail. The degree of competitive interaction and the implications are discussed. Considerable overlap occurs in the diet of goats and cattle, and between sheep and cattle. Sheep, cattle and kangaroos eat similar foods, where there is a wide choice, but the degree of competition tends to be minimized by spatial and temporal separation. Under conditions of severe feed shortage kangaroos and livestock both concentrate on areas supporting the most nutritious forage and competition is intensified.

Population Fluctuations and Range Community Preference of Red Kangaroos in Central Australia

(1) The distribution of red kangaroos, Megaleia rufa, was determined from aerial surveys at approximately 3-weekly intervals over a 41 year period, during which climatic conditions varied from drought to the wettest on record. The study area in the arid rangelands of central Australia was approximately 158 km2 and contained a complex diversity of grassland, Mulga shrubland and woodland communities. (2) Numbers of kangaroos on the paddock ranged up to 564, seven times the long-term mean of 81, during the drought period, and fluctuated between 9 and 204 at other times. These smaller changes in numbers occurred frequently between surveys as kangaroos moved into and out of the paddock in response to changes in forage conditions due to sporadic rains or fire. (3) The Mulga-annual grass community received the greatest average use by kangaroos, followed by Mulga-perennial grass and Open woodland. Less use was made of Flood plains, Gilgaied plains, Foothill fans, and several minor communities. The Treeless Plains communities and Open woodland were used by kangaroos as a refuge during drought and were little used during good forage conditions, while Mulga-perennial grass community showed an opposite trend in relative use. The Mulga-annual grass community, however, did not show any consistent trend with changes in forage conditions. (4) Results indicate that kangaroos are nomadic in response to changing forage conditions and their home range greatly exceeds the area of the study site.

The energetic cost of bipedal hopping in small mammals

Recent studies of locomotion in red kangaroos (Megaleia rufa, 18–28 kg)1 and Australian hopping mice (Notomys cervinus, 36.6 g)2 have indicated that over a certain range of speeds the energetic cost of bipedal hopping locomotion may become independent of speed. As much as 70% of the decrement in kinetic energy which takes place when the kangaroo lands may be stored in elastic elements and used to propel the kangaroo upwards and forwards as it takes off (leaving only 30% to be added by the muscles)3,4. Presumably, this same phenomenon could be exploited by all bipedal hopping mammals and it seems possible that at high speeds this specialized mode of locomotion could result in large energetic savings when compared with the costs incurred by a similarly sized quadruped running at the same speed. This hypothetical lower cost of locomotion has been invoked as an explanation for the rather common occurrence of bipedal hoppers among desert and plains dwelling mammals, as it might substantially reduce the energetic cost of foraging, or travelling, for animals utilizing widely dispersed resources5–7. The purpose of the present study was to extend the assessment of the metabolic expense of bipedal hopping to a broader range of body sizes and mammalian taxa. Using indirect calorimetry we measured the cost of locomotion for three bipedal hopping eutherians (0.03–3.0 kg) and one bipedal hopping marsupial (1.1 kg). When properly trained for sustained running, none of the three species deviated from the expected quadrupedal pattern relating cost of locomotion to running speed, even while running fully bipedally. Bipedality must therefore be associated with benefits other than those related to the energetic costs of locomotion.

A Helicopter Quadrat Census for Mule Deer on Uncompahgre Plateau, Colorado

Mule deer (Odocoileus hemionus) were censused by 2 observers in a helicopter during 3 consecutive winters on 193 0.6475-km2 quadrats distributed, in a stratified random sampling design, throughout 1,688 km2 of pinyon-juniper (Pinus edulis-Juniperus osteosperma) winter range on the Uncompahgre Plateau, in southwestern Colorado. Quadrats were plotted on maps and aerial photos, and the 4 corners were permanently marked on the ground. Estimates of total deer population and 90% confidence limits for the 3 years were 11,401 + 2,205, 17,884 + 4,042, and 17,085 ? 2,951, respectively. During the 2nd and 3rd years the sample was sufficient to permit estimation of the population within 22.6 and 17.3% of the mean number of deer per 2.59 km2, respectively, with 90% confidence. Stratified random sampling reduced variance of the mean number of deer seen per 2.59 km2 by 42, 21, and 37%, respectively, relative to simple random sampling during the 3 years of the census. Procedures for conducting a census of this type and methods for minimizing observer error are detailed. J. WILDL. MANAGE. 44(3):632-639 This study was initiated as a result of widespread concern among wildlife managers and the public that Colorado mule deer populations had suffered recent declines. These declines could not be documented, however, due to lack of deer census systems that had been implemented and tested on a large scale (Gill 1976, Wallmo et al. 1976). The need for such a census sytem was, therefore, clearly recognized. Mountainous terrain and relative inaccessibility of many areas in the West compound problems of censusing deer. A technique employing a helicopter to survey randomly located quadrats was selected for assessment of feasibility because it appeared to offer a reasonable solution to those problems. Numerous studies have evaluated aerial census systems for large ungulates. Many of these have involved counting African animals along transects (Goddard 1967, Bell et al. 1973, Norton-Griffiths 1973). Bergerud (1963) used the transect method to count caribou (Rangifer tarand s) in Newfoundland and Labrador, and Caughley et al. (1976) used it in Australia to count kangaroos (Megaleia rufa, Macropus giganteus and fuliginosus) and domestic sheep. The transect system is suited only to use in relatively flat terrain, however, because counting errors occur in mountainous terrain due to variations in altitude and banking the aircraft, which affect definition of the transect strip (Pennycuick 1969). Big game animals on quadrats can be censused using a helicopter in the steepest mountain

The predictability of rain and the foraging patterns of the red kangaroo (Megaleia rufa) in central Australia

Despite the dramatic impact of rain in the central Australian desert, the occurrence of rain is very unpredictable, and there is strong evidence that it does not influence either density or dispersion of feeding red kangaroos. In this study, both community type and season significantly influenced density (P

Acid and alkaline forms of the higher oxidation state of kangaroo, horse, and sperm whale myoglobin

Myoglobin(IV), the derivative of myoglobin at the formal oxidation state IV, prepared from kangaroo (Megaleia rufa), horse, or sperm whale myoglobin, when cooled to liquid nitrogen temperature, assumes acid and alkaline forms with different optical spectra. The essential features of the optical spectra of the acid forms are the same as those of leghemoglobin(IV) and are very similar to those of optical spectra of the red higher oxidation states of catalases and peroxidases. This shows that the configuration of the heme iron is the same throughout these compounds. That configuration is believed to be Fe(IV) in a porphyrin environment. The optical spectra of alkaline mammalian myoglobin(IV), like that of alkaline leghemoglobin(IV), resemble those of the alkaline low spin ferric proteins. Kangaroo myoglobin(IV) may be prepared by reaction of ferrous myoglobin with hydrogen peroxide. The acid forms of myoglobin(IV) are conveniently prepared by cooling solutions in borate buffers, initially pH 8.3, to liquid nitrogen temperature. At this temperature borate buffers become acidic.

The ontogeny of the pancreas in macropodid marsupials

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.

Observations on the vasculature of the reproductive tract in some australian marsupials.

AbstractThe origin, distribution and structure of the blood vessels of the female reproductive tract and the testis of the brush possum (Trichosurus vulpecula) were studied using latex and silicone rubber casting and histological techniques. Latex casts of the vessels of the female tract were also studied in five macropod species – Macropus giganteus, M. eugenii, M. agilis, Megaleia rufa and Thylogale billardierii, and in the common wombat (Vombatus ursinus).The female reproductive tract in the brush possum was supplied and drained by four major sets of paired vessels – ovarian, cranial urogenital, caudal urogenital, and internal pudendal arteries and veins. These vessels formed substantial anastomoses with one another on each side of the midline, and also across‐the‐midline anastomoses. The proximal part of the ovarian artery ran in close apposition to the ovarian vein, which received one or more large uterine branches. In its distal protion the ovarian artery gave rise to a leash of small, tortuous ovarian branches, which wound around and between the plexiform ovarian veins.The testicular arteries and veins in this species also ran in close apposition to one another. Both arteries and veins branched into many smaller, mildly tortuous, parallel vessels in the spermatic cord, which reunited before entering the testis.The blood vessels of the reproductive tract in all of the macropod species studied, and in the common wombat, were basically similar to those of the brush possum.The intimate structural relationships between ovarian arteries and veins, and their ovarian branches, in these marsupials are suggestive of specializations for counter‐current exchange between venous and arterial blood. However, in contrast to those of the testicular vessels where heat exchange is a demonstrated function, their physiological significance remains unknown.

Harvesting Kangaroos in New South Wales

In New South Wales the red kangaroo, Megaleia rufa (Desmarest), and the two species of grey kangaroo, Macropus giganteus Shaw and M. fuliginosus (Desmarest), are harvested commercially. In 1975 the National Parks and Wildlife Service issued permits for 239,764 kangaroos to be shot, but only 48,200 red and 70,200 grey kangaroos were taken. Over western New South Wales the numbers shot represented only 2.3% of the reds and 3.8% of the greys. Most of the harvesting was in areas where kangaroos were abundant. Where densities were low few animals were shot but they accounted for a high proportion of the standing crop-in some areas over 15%. Possible reasons for this under the present management system are discussed, together with the implications for future management.

The Diet of the Dingo in Western Australia.

Between 1971 and 1976, 160 stomachs of dingo [Canis dingo] were collected from rangeland of Western Australia, with conditions ranging from those of arid Nullarbor to tropical Kimberley. There were 14 empty stomachs. In the other stomachs, mammals were the main food by percentage of number and volume. The main mammal foods were macropods, mainly red kangaroo (Megaleia rufa) and euro (Macropus robustus), which together were over 70% by volume of food and occurred in over 65% of stomachs. There were small amounts of domestic sheep, cattle or goats and some food had been eaten as carrion, probably including one sheep that had been shot. Birds provided small volume but were found in 15% of stomachs; the main bird was emu (Dromaius novaehollandiae). Small mammals, reptiles and insects were found and grasshoppers or locusts may be an important food during plagues of those insects. Where rabbits occurred they were a large part of the diet and dingo population may fluctuate in response to changes in rabbit population. Dingos seemed to be opportunistic feeders and to prefer wild animals to domestic stock even though those were usually equally available.

Seasonal variations in the body temperatures of unrestrained kangaroos (Macropodidae: Marsupialia)

1. 1. Nychthemeral and seasonal variations in the body temperatures of 3 species of kangaroos, Megaleia rufa, Macropus robustus and Macropus giganteus, held in outdoor yards, were studied by means of radio-telemetry. 2. 2. Mean daily rectal temperatures of all species were between 35.1 and 36.9°C and no consistent differences between species or seasons were found. 3. 3. Nychthemeral variations in rectal temperatures of red kangaroos were small (<1.5°C) in the winter months but increased in the warmer months (1.0–2.5°C). 4. 4. Seasonal variations in subcutaneous temperatures, which were higher in the warmest month, possibly reflect some degree of seasonal acclimatization.

Numbers, Distribution and Harvesting Rate of Kangaroos on the Inland Plains of New South Wlaes

The number of kangaroos on the plains of New South Wales (496000 km2) was estimated as 2 073 000 &amp; 98 000 red kangaroos, Megaleia rufa, and 1 578 000 i- 84 000 grey kangaroos, Macropus giganteus and M. fuliginosus. The overall densities were 4.18 reds and 3.18 greys per square kilometre. Sheep outnumbered kangaroos by five to one. Red kangaroos were most numerous in the north-west of the state, greys in the north-central region. The legal harvest on the survey area in 1975 was 48 100 reds and 60 300 greys, representing 2.3% of the population of reds and 3.8% of the greys. Density is mapped for both red and grey kangaroos, and a design is offered for monitoring subsequent changes in density by aerial survey.

Seasonal Changes in Diet Preferences of Free-Ranging Red Kangaroos, Euros and Sheep in Western New South Wales.

Stomach contents of free-ranging animals were analysed botanically for low Atriplex shrubland in western New South Wales, Australia, during 1972-74 in good seasons producing abundant growth and diversity of vegetation. Red kangaroo (Megaleia rufa), euro (Macropus robustus) and sheep (Ovis aries) selected grass and forbs when those were readily available. In poorer pasture sheep selected mainly flat-leaved chenopods (saltbush) and kangaroos selected mainly grass with different amounts of flat- or round-leaved chenopods. Euros were the most selective, eating grass even when there was little grass present. Potential overlaps in diet between kangaroos and sheep were greatest in good pasture and least in the poorest conditions. The other groups of plants considered were non-chenopod shrubs and browse. Extent of overlap was not clear, because animals may have eaten different species within the groups of plants. The study period did not include any severe drought, in which overlap in diet and competition between animal species would have been most significant.

The effects of a severe drought on the morphology of the adrenal glands and other indices of health in the red kangaroo Megaleia rufa (Desmarest) in north‐western New South Wales*

AbstractDrought adversely affects health and reproduction in red kangaroos (Megaleia rufa) (Desmarest). There is a significant drop in body weight in adult kangaroos, and growth rates of pouch young are depressed. In adult males both lobes of the pituitary gland decrease in size. All zones in the adrenal glands become smaller and lipid stores increase. In adult females the posterior lobe of the pituitary increases in size and, although all zones in the adrenal glands shrink the evidence suggests continued stimulation of the Zonae fasciculata and glomerulosa. The decrease in size of the adrenal glands is accompanied by cortical folding and nodulation and other structural changes.Growth curves of pouch young are shown to fit the Johnson‐Schumacher curve Y = A * exp [‐b/(x + k)].The data substantiate the findings of earlier workers but suggest that anoestrous female red kangaroos suckling small young may be better adapted to withstand drought than males.

Experiments in Aerial Survey

By use of balanced experiments amenable to analysis of variance we explored the effects of several factors on the accuracy of aerial survey estimates of animal density. Speed, height above ground, transect width, and observers had significant effects, whereas time of day, fatigue of observers, and length of survey were less important. We tested the hypothesis that a regression of observed density on speed, height, and transect width could be extrapolated backward to estimate true density at zero values of these survey variables. The results were generally consistent with this expectation. The uses of this technique are outlined, with examples, in the context of correcting an observed density to an estimate of true density, of calibrating one observer against another, and of comparing the results from aerial surveys flown at different speeds and heights, and with different widths of transect. The field experiments utilized red kangaroos (Megaleia rufa) at unknown densities and domestic sheep at known densities. Laboratory experiments were performed on dots of known density projected onto a screen. Before the model is accepted as generally applicable it must be tested against several other species in a variety of habitats. J. WILDL. MANAGE. 40(2):290-300 During the early stages of World War II, Royal Air Force crews experienced great difficulty in hunting German submarines in the Bay of Biscay. Their flight path seldom passed near a surfaced submarine and even when it did they often failed to see it. This and related problems forced the birth of an infant branch of applied mathematics called operations research. It swiftly reduced the problem of hunting submarines to its theoretical essentials (Morse and Kimball 1960). A similar problem, amenable to similar treatment, is posed by the difficulty of estimating animal populations from the air. Over the last decade evidence has accumulated steadily to show that aerial surveys provide underestimates, often gross underestimates, of animal density. These data from a broad range of species and habitats were summarized by Caughley (1974). While that paper was in press, further evidence appeared (LeResche and Rausch 1974) showing that the accuracy of counting moose (Alces alces) from the air was influenced significantly by a number of factors. Experienced observers counted only 68 percent of moose on a quadrat; inexperienced observers counted 43 percent. This degree of error is completely unacceptable when the aim is to calculate population size as a prelude to estimating a sustained yield, but there are strong grounds for suspecting that the error cannot be eliminated by refining techniques, by elaborating the survey design, or by hoping that a technological solution such as greatly improved infrared sensing is just around the corner. The alternative is to accept that the best of observers, in the most favorable conditions of observation, will fail to observe many of the animals at which he is staring. This was the starting point of an approach introduced previously (Caughley 1974) in which partial regression analysis was suggested as a means of estimating true density. Since sightability declines with increasing speed, height above ground, and transect width, a regression of observed density on these variables should estimate true density as the y-intercept constant a. 1Study supported by the Australian Research Grants Committee. 290 J. Wildl. Manage. 40 (2) :1976 This content downloaded from 157.55.39.255 on Mon, 01 Aug 2016 06:11:50 UTC All use subject to http://about.jstor.org/terms EXPERIMENTS IN AERIAL SURVEY * Caughley et al. 291 Table 1. Experimental design for the field surveys. Area Transect Sampling surveyed Height Speed width unit Expt. (km2) (m) (km/h) (m) (0.5 km2) Species Observer 1 50 46 129 50 858 red kangaroos G.C., R.S. 91 161 100 858 183 193 200 858 2 70 46 161 100 864 red and grey G.C., D.S. 91 193 200 864 (Macropus giganteus) 183 193 200 864 kangaroos 3 16 46 161 100 576 sheep G.C., D.S. 91 193 200 576 183 193 200 576 The purpose of the present paper is to explore this hypothesis in greater depth by determining the relationship between observed density and the survey variables, and the extent to which these relationships change as viewing conditions change. Finally, we will show that factors can be calculated by partial regression to correct standard aerial survey estimates for visibility bias. This paper reports the results from four experiments in aerial survey. Since the design of each, and the need for the experiment itself, was dictated by the results of the previous experiment, these will be reported in chronological order. We are grateful to T. Mathews who piloted for the experiments; to G. Wilson for survey piloting; to R. Goldsby, E. McLaughlin, and N. Crisp for providing us with the facilities of their stations and for their hospitality; and to G. Courtice for assisting in the simulation experiment.

Gravity as the sole navigational aid to the newborn quokka.

ALTHOUGH there is general agreement on the sequence of events at birth for several marsupial species1, it is still not known how the newborn joey navigates on its journey from the mother's cloaca to her pouch. Frith and Calaby2 have postulated that, at birth, the red kangaroo (Megaleia rufa) “… has large nostrils and presumably a well developed sense of smell which probably plays a major part in its location of the pouch”. On the other hand, Hartman3 has suggested that the newborn opossum (Didelphis virginiand) was “negatively geotropic” though he has now modified this view considerably4, as histological studies have revealed that the vestibular apparatus of the newborn animal is undirTerentiated and therefore nonfunctional5,6. To investigate whether one of these mechanisms2,4 could account for the behaviour of the newborn quokka (Setonix brachyurus) we have observed parturition in this macropodid marsupial.