Social Organization, Reproduction and Feeding Behaviour of a Population of Yellow-Bellied Gliders, Petaurus Australis (Marsupialia: Petauridae).

1985 ◽  
Vol 12 (1) ◽  
pp. 1 ◽  
Author(s):  
SA Craig
Keyword(s):  
Feeding Behaviour ◽  
Small Population ◽  
Management Implications ◽  
Open Forest ◽  
Monogamous Relationship ◽  
Home Area ◽  
Stable Family ◽  
Plant Exudates ◽  
Number Of Individuals ◽  
Petaurus Australis

Population dynamics, habitat use and feeding behaviour in a small population of P. australis were studied in 190 ha of Tall Open Forest in the Victorian Central Highlands. Between October 1979 and December 1982, 13 marked individuals were trapped on 71 occasions during 1223 trap-nights. Gliders formed relatively stable family groups, each comprising a single resident pair living in a monogamous relationship with or without dependent offspring. They bred between August and October. Four females were observed with a single pouch young. Each pair occupied substantially separate ranges of between 30 and 55 ha. The maximum number of individuals estimated to be present during any month was eight. Den hollows were located only in living trees and one family group of three individuals used at least eight den trees within their home area. All sap-site trees were located mid-slope and were used mainly during the winter-spring months. Analysis of faeces and direct observation of feeding animals indicated that the bulk of this glider's diet is made up of arthropods, supplemented with insect and plant exudates. Some management implications, based on the life-history requirements of this glider, are discussed.

Evolutionary genetics of small populations

2017 ◽  
Author(s):  
Richard Frankham ◽  
Jonathan D. Ballou ◽  
Katherine Ralls ◽  
Mark D. B. Eldridge ◽  
Michele R. Dudash ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Population Size ◽  
Evolutionary Genetics ◽  
Small Population ◽  
Small Populations ◽  
Effective Population ◽  
Genetic Management ◽  
Evolutionary Genetic ◽  
Loss Of Genetic Diversity ◽  
Number Of Individuals

Genetic management of fragmented populations involves the application of evolutionary genetic theory and knowledge to alleviate problems due to inbreeding and loss of genetic diversity in small population fragments. Populations evolve through the effects of mutation, natural selection, chance (genetic drift) and gene flow (migration). Large outbreeding, sexually reproducing populations typically contain substantial genetic diversity, while small populations typically contain reduced levels. Genetic impacts of small population size on inbreeding, loss of genetic diversity and population differentiation are determined by the genetically effective population size, which is usually much smaller than the number of individuals.

Feeding behaviour of the yellow-bellied glider (Petaurus australis) at the western edge of its range

1999 ◽  
Vol 26 (2) ◽  
pp. 199 ◽  
Author(s):  
Susan M. Carthew ◽  
Ross L. Goldingay ◽  
Darryl L. Funnell
Keyword(s):  
Sap Flow ◽  
Feeding Behaviour ◽  
Food Item ◽  
Food Resource ◽  
Geographic Range ◽  
Important Food ◽  
Ecological Requirements ◽  
South West ◽  
Petaurus Australis ◽  
Important Food Item

This study provides the first assessment of the diet of the yellow-bellied glider (Petaurus australis) in the south-west portion of its range near the Victorian–South Australian border. Examining its diet in this region is viewed as being fundamental to understanding the ecological requirements of the species. Observations were conducted over a five-year period on gliders from five distinct groups. Sap was the most important food item throughout the year and accounted for 83% of 407 feeding observations. Each group of gliders used up to 21 different trees for sap, but during any sample period only 1–8 trees were used. This represents a vastly different pattern of use of sap trees to that described in any earlier study. Some trees were visited more often than others, and these tended to be heavily scarred, indicating use over many years. Other food types were arthropods and honeydew and, to a lesser extent, nectar. This study also revealed that the yellow- bellied glider is not dependent on a diversity of tree species nor on a winter-flowering species. We provide a review of the diet of the yellow-bellied glider throughout its range. This shows that the yellow-bellied glider is reliant on sap as a food resource but particularly so at both ends of its geographic range. The reason for this is unclear, but there is definitely a need for further study of sap-flow patterns in eucalypts.

Loud Calls of the Yellow-Bellied Glider, Petaurus-Australis - Territorial Behavior by an Arboreal Marsupial

1994 ◽  
Vol 42 (3) ◽  
pp. 279 ◽  
Author(s):  
RL Goldingay
Keyword(s):  
Feeding Behaviour ◽  
Home Ranges ◽  
Insufficient Data ◽  
Loud Calls ◽  
The Core ◽  
Calling Behaviour ◽  
Highly Correlated ◽  
Petaurus Australis ◽  
Territorial Function ◽  
Intergroup Spacing

The yellow-bellied glider, Petaurus australis, is possibly the most vocal of all marsupials but little attention has been given to the functional significance of its calling behaviour. This study describes various traits of the calling behaviour and examines their significance. The traits were: (i) calling occurred throughout the night but was more frequent in the first 3 h of activity; (ii) calling frequency was significantly greater near the boundary (9.1 calls per 30 min) rather than the core (2 calls per 30 min) of glider home ranges; (iii) calling and gliding were highly correlated; (iv) calling rate was influenced by a glider's feeding behaviour; and (v) experimental playback of calls (simulating an intruder) resulted in calling rates by gliders that were significantly higher after the playback (6.3 calls per 15 min) than before the playback (2.8 calls per 15 min). Gliders approached the area of playback in 50% of tests; in one instance from a distance of 200 m. Assessment of the calling behaviour of gliders, by reference to seven functions proposed for loud calls of primates, indicates that the most likely function of calls is to mediate intergroup spacing. The traits of the calling behaviour, together with the observation that glider home ranges are virtually exclusive of those of neighbouring groups, suggest that calls serve a territorial function. The use of vocalisations appears to be the most effective method for advertising territories, which commonly exceed 50 ha. A review of the use of loud calls by other species of arboreal marsupial showed that at present there are insufficient data to enable an adequate assessment of the function of loud calls among these species.

scholarly journals Establishment of an Endangered species on a private nature refuge: what can we learn from reintroductions of the bridled nailtail wallaby Onychogalea fraenata?

Oryx ◽  
2012 ◽  
Vol 46 (2) ◽  
pp. 240-248 ◽  
Author(s):  
Lisa Kingsley ◽  
Anne Goldizen ◽  
Diana O. Fisher
Keyword(s):  
Extinction Risk ◽  
Good Condition ◽  
Small Population ◽  
Juvenile Survival ◽  
Mammal Species ◽  
Preferred Habitat ◽  
Introduced Predators ◽  
Number Of Individuals ◽  
Large Groups

AbstractTranslocation and reintroduction are used to reduce extinction risk associated with a small population and range size in threatened mammal species. We evaluated the outcome of a reintroduction of the bridled nailtail wallaby Onychogalea fraenata to Avocet Nature Refuge, a private refuge in central Queensland, Australia. This macropod was also reintroduced to Idalia National Park in western Queensland in 1996 and occurs in one natural population in central Queensland. We estimated population growth, adult and juvenile survival, and distribution changes since the last release of O. fraenata to Avocet in 2005, and evaluated female reproductive success and health. Although animals were in good condition, population size was a tenth of that of the 1996 Idalia reintroduction reported after 3 years and, unlike at Idalia, juvenile survival at Avocet was low. The likely causes are consistent with predictors of translocation and reintroduction failures in mammals. These are predation, the small number of individuals in each release, the likely suboptimal health status of reintroduced individuals, drought, and possibly lack of dispersal from the small area of preferred habitat. The lessons of this reintroduction are that future attempts are likely to have the best chance of success if they occur in non-drought years, at sites with large, non-fragmented areas of brigalow forest, involve the release of large groups of animals together, and are accompanied by intensive, long-term baiting to control introduced predators.

Gliding performance in the yellow-bellied glider in low-canopy forest

2014 ◽  
Vol 36 (2) ◽  
pp. 254 ◽  
Author(s):  
Ross L. Goldingay
Keyword(s):  
Habitat Connectivity ◽  
Horizontal Distance ◽  
Horizontal Branch ◽  
Main Trunk ◽  
Open Forest ◽  
The Mean ◽  
Western Victoria ◽  
Petaurus Australis

Knowledge of the gliding performance of gliding mammals is fundamental to understanding how these species have adapted to their environment and is of increasing relevance to their conservation. I describe aspects of the glide performance of the yellow-bellied glider (Petaurus australis) based on 22 glides of 17 individuals within 20–30-m-high open forest in western Victoria. Gliders launched into a glide from a horizontal branch that was, on average, 2.8 m below the top of a tree, 5.2 m out from the main trunk and 18.5 m above the ground. Gliders landed on the trunks of trees 5.8 m above the ground. The mean horizontal glide distance was 25.2 ± 1.5 m (s.e.) (range = 19–45 m), producing a glide ratio (horizontal distance/height dropped) of 2.0 and a glide angle of 27.3°. These values are similar to those reported for other gliding petaurids in low-canopy forest. This knowledge should be used to guide the management of habitat connectivity for yellow-bellied gliders.

Seed dispersal by black-handed tamarins, Saguinus midas niger (Callitrichinae, Primates): implications for the regeneration of degraded forest habitats in eastern Amazonia

2000 ◽  
Vol 16 (5) ◽  
pp. 709-716 ◽  
Author(s):  
Ana Cristina M. Oliveira ◽  
Stephen F. Ferrari
Keyword(s):  
Feeding Behaviour ◽  
Forest Regeneration ◽  
Secondary Forest ◽  
Fragmented Landscape ◽  
Degraded Forest ◽  
Forest Fragment ◽  
Plant Exudates ◽  
Pass Through ◽  
Free Ranging ◽  
Forest Habitats

The feeding behaviour of free-ranging black-handed tamarins, Saguinus midas niger, was monitored over 6 mo in a forest fragment in eastern Amazonia. The tamarins' diet included arthropods and plant exudates, but was predominantly frugivorous (87.5% of feeding records, 18 plant species) in all months. The seeds of at least six species were ingested whole and defecated intact. Ingested seeds were relatively large, but those with diameter > 1 cm or length > 2 cm were discarded. Seeds took 2–4 h to pass through the digestive tract, and more than half (50.6%) were dispersed to a habitat different from that in which they were ingested. A fifth (19.3%) of all seeds were dispersed from primary to secondary forest, indicating that S. m. niger may play an important rôle in forest regeneration, a rôle that will become increasingly important in the fragmented landscape of eastern Amazonia.

Evolutionary genetics of small populations

2019 ◽  
pp. 15-30
Author(s):  
Richard Frankham ◽  
Jonathan D. Ballou ◽  
Katherine Ralls ◽  
Mark D. B. Eldridge ◽  
Michele R. Dudash ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Population Size ◽  
Evolutionary Genetics ◽  
Small Population ◽  
Small Populations ◽  
Effective Population ◽  
Genetic Management ◽  
Loss Of Genetic Diversity ◽  
Number Of Individuals

Genetic management of fragmented populations involves the application of evolutionary genetic theory and knowledge to alleviate problems due to inbreeding and loss of genetic diversity in small population fragments. Populations evolve through the effects of mutation, natural selection, chance (genetic drift), and gene flow. Large outbreeding sexually reproducing populations typically contain substantial genetic diversity, while small populations typically contain reduced levels. Genetic impacts of small population size on inbreeding, loss of genetic diversity and population differentiation are determined by the genetically effective population size, which is usually much smaller than the number of individuals.

Perceptual Learning of Vocoded Speech With and Without Contralateral Hearing: Implications for Cochlear Implant Rehabilitation

2020 ◽  
pp. 1-10
Author(s):  
Martin Chavant ◽  
Alexis Hervais-Adelman ◽  
Olivier Macherey
Keyword(s):  
Cochlear Implant ◽  
Perceptual Learning ◽  
Speech Signal ◽  
Training Phase ◽  
Monosyllabic Words ◽  
Low Pass ◽  
Contralateral Ear ◽  
Number Of Individuals ◽  
Insight Into ◽  
Vocoded Speech

Purpose An increasing number of individuals with residual or even normal contralateral hearing are being considered for cochlear implantation. It remains unknown whether the presence of contralateral hearing is beneficial or detrimental to their perceptual learning of cochlear implant (CI)–processed speech. The aim of this experiment was to provide a first insight into this question using acoustic simulations of CI processing. Method Sixty normal-hearing listeners took part in an auditory perceptual learning experiment. Each subject was randomly assigned to one of three groups of 20 referred to as NORMAL, LOWPASS, and NOTHING. The experiment consisted of two test phases separated by a training phase. In the test phases, all subjects were tested on recognition of monosyllabic words passed through a six-channel “PSHC” vocoder presented to a single ear. In the training phase, which consisted of listening to a 25-min audio book, all subjects were also presented with the same vocoded speech in one ear but the signal they received in their other ear differed across groups. The NORMAL group was presented with the unprocessed speech signal, the LOWPASS group with a low-pass filtered version of the speech signal, and the NOTHING group with no sound at all. Results The improvement in speech scores following training was significantly smaller for the NORMAL than for the LOWPASS and NOTHING groups. Conclusions This study suggests that the presentation of normal speech in the contralateral ear reduces or slows down perceptual learning of vocoded speech but that an unintelligible low-pass filtered contralateral signal does not have this effect. Potential implications for the rehabilitation of CI patients with partial or full contralateral hearing are discussed.

Optimal Experimental Design With Nesting of Persons in Organizations

2013 ◽  
Vol 221 (3) ◽  
pp. 145-159 ◽  
Author(s):  
Gerard J. P. van Breukelen
Keyword(s):  
Repeated Measures ◽  
Optimal Number ◽  
Health Centers ◽  
Randomized Experiments ◽  
Optimal Sample ◽  
Treatment Conditions ◽  
Sampling Cost ◽  
Nested Designs ◽  
Simple Equations ◽  
Number Of Individuals

This paper introduces optimal design of randomized experiments where individuals are nested within organizations, such as schools, health centers, or companies. The focus is on nested designs with two levels (organization, individual) and two treatment conditions (treated, control), with treatment assignment to organizations, or to individuals within organizations. For each type of assignment, a multilevel model is first presented for the analysis of a quantitative dependent variable or outcome. Simple equations are then given for the optimal sample size per level (number of organizations, number of individuals) as a function of the sampling cost and outcome variance at each level, with realistic examples. Next, it is explained how the equations can be applied if the dependent variable is dichotomous, or if there are covariates in the model, or if the effects of two treatment factors are studied in a factorial nested design, or if the dependent variable is repeatedly measured. Designs with three levels of nesting and the optimal number of repeated measures are briefly discussed, and the paper ends with a short discussion of robust design.

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