scholarly journals Ectoparasites are unlikely to be a primary cause of population declines of bent-winged bats in south-eastern Australia

Author(s):  
Peter H. Holz ◽  
Linda F. Lumsden ◽  
Jasmin Hufschmid
2015 ◽  
Vol 21 (4) ◽  
pp. 271 ◽  
Author(s):  
Gregory R. Johnston ◽  
Maxwell H. Waterman ◽  
Clare E. Manning

Globally, pelican populations have decreased, with three species being of conservation concern. Australian pelicans (Pelecanus conspicillatus) are not regarded as endangered, but have declined across south-eastern Australia. Information on their movements and causes of mortality are required to interpret the importance of these regional declines to the species’ global population. We explored patterns of movement and causes of mortality by analysing recoveries from 14 615 Australian pelicans banded over 37 years between 1969 and 2006. Data from 243 leg band recoveries showed that Australian pelicans move distances of up to 3206 km, and travel across the species’ entire geographic range, within a year of fledging. We found little evidence for the popular notion that these birds move en masse from the coast to inland areas in response to flooding rains. Maximum recorded age of a banded Australian pelican was 15 years. The banding data suggest that the regional pelican declines could reflect long-distance movements rather than an overall population response. However, a concentration of band returns from south-eastern Australia where the declines have been recorded, and the high incidence of human-induced deaths (16.4%) suggest otherwise. Accurate assessment of population trends in long-lived, long-distance nomads such as Australian pelicans requires assessment at a continental scale. Our results emphasise the importance of knowledge about fundamental aspects of a species’ biology for accurate interpretation of regional population declines.


2003 ◽  
Vol 51 (6) ◽  
pp. 611 ◽  
Author(s):  
C. A. Belcher

The tiger quoll is a large marsupial carnivore that occurs in forested habitat in south-eastern Australia. Three tiger quoll populations were trapped for up to six years and data on population parameters, including size, structure, sex ratio, adult : subadult ratio, weight, breeding characteristics, age and longevity were recorded for each population. Sex ratios (♂ : ♀) varied from 5 : 1 to 0 : 1. Population size and age structure reflected previous mortality events and social organisation traits, with all populations showing signs of instability due to disturbance events. Males did not reach full adult weight until three years of age and females until two years. Mean adult male weight was 2.81 kg ± 0.50 (s.d.) (range 2.0–4.2 kg) and mean adult female weight was 1.73 kg ± 0.22 (s.d.) (range 1.2–2.1 kg). Most females did not breed before two years of age and were recorded breeding up to four years of age. A proportion of females did not appear to breed in consecutive years. Matings were estimated to have occurred between late June and early August and births between mid-July and late August. Pouch litter size varied from 4 to 6 with a mean of 5.38 ± 0.65 (s.d.). The adult to juvenile ratio suggests that the mean number of young weaned per female is probably as low as one or two. Monitoring of four females found that the average number of young weaned was three with a range of 2–4. The maximum age recorded was five years. Population declines were found to correlate with 1080 poison baiting programmes, but not with selective logging.


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