Saunders D.A.,CSIRO |
Wintle B.A.,University of Melbourne |
Mawson P.R.,0 Labouchere Road |
Dawson R.,Locked Bag 104
Biological Conservation | Year: 2013
Birds use a number of environmental cues to time their breeding season to maximise their chances of raising young when food is most abundant. Such cues include photoperiod, temperature and rainfall. In very arid regions, birds may start egg-laying with the onset of rain to allow fledging to coincide with the availability of grass seeds. However the influence of rainfall on timing of egg-laying in areas with variable, but more reliable, rainfall has not been as clear. Carnaby's Cockatoo, an endemic species of southwestern Australia, a region with a Mediterranean climate, is known colloquially as " the rainbird" as its movements to the breeding areas appear to coincide with the start of the wetter part of the year. Here we use a long-term data set on the breeding of this species (24. years of data from 1969 to 2011) to quantify the link between the timing of autumn rains and the commencement of egg-laying in this endangered cockatoo. We found a tight synchrony which indicates a strong reliance of the species on early autumn rains as a cue for breeding. We describe the conservation implications of increased variability in timing and quantity of rainfall for the long-term viability of Carnaby's Cockatoo. © 2013 Elsevier Ltd.
Le Souef A.T.,Murdoch University |
Stojanovic D.,Bird Life Western Australia |
Stojanovic D.,Australian National University |
Vitali S.D.,0 Labouchere Road |
And 2 more authors.
Pacific Conservation Biology | Year: 2013
Despite the widespread use of telemetry to track the movements of many different avian species, there are few published studies describing tracking methods for large psittacine birds. Due to their powerful bills and inquisitive demeanours, large parrots may damage valuable transmitters and confound telemetry studies. We undertook a captive trial of three attachment methods (collar, harness and tail-mount) and a novel weak-link harness design for black cockatoos (Calyptorhynchus latirostris, C. baudinii and C. banksii naso). Mean retention times for the transmitter packages ranged from 44 to 384 days. There was no skin or feather damage to the birds associated with transmitter attachments. The results showed sufficient transmitter retention times to allow for the collection of valuable movement and survival data, with no obvious ill effects on animal welfare, and are a first step towards using transmitters on wild cockatoos.
White N.E.,Curtin University Australia |
White N.E.,Murdoch University |
Bunce M.,Curtin University Australia |
Bunce M.,Murdoch University |
And 5 more authors.
Diversity and Distributions | Year: 2014
Aim: We examined how the threatened and endemic white-tailed black cockatoos of Western Australia have responded genetically to recent and comprehensive habitat loss with the ultimate aim of identifying units for conservation. We assessed the population structure, connectivity and genetic diversity at spatial and temporal scales for Calyptorhynchus baudinii and C. latirostris, which have undergone dramatic population declines. Genetic comparisons of pre- and post-population decline were carried out by including historical samples dating back to 1920. We examined samples collected from across 700 km of their distribution and sampled approximately 1% of the current population census size to produce significant insights into the population genetics of white-tailed black cockatoos and generate genetic information crucial for conservation management. Location: Southwest corner of Western Australia. Methods: Six hundred and eighty-four cockatoo samples were collected from 1920 to 2010 and profiled with 19 microsatellites to identify spatial population structure and loss of genetic diversity. Results: The temporal and spatial microsatellite data illustrated that the geographically defined genetic structuring in white-tailed black cockatoos is likely to represent a recent phenomenon. We identified: (1) spatial population substructure east and west of extensively cleared habitat (>95,800 km2), but the historical samples clustered with the current western population, regardless of origin, (2) a regional loss of allelic diversity over 3-4 generations for the current eastern population, (3) a lack of a genetic signal of the recent population decline, but perhaps a mid-Holocene population collapse and lastly, (4) limited genetic differentiation between the two currently recognized white-tailed black-cockatoo species suggests a review of taxonomy and/or management units should be undertaken. Main conclusion: Based on extensive spatio-temporal sampling, we have demonstrated that recent anthropogenic habitat modifications have affected the genetic structure of a long-lived and highly mobile species. Our results have identified areas of high conservation value and the importance of maintaining native vegetation migration corridors. © 2014 John Wiley & Sons Ltd.
Mayberry C.,University of Western Australia |
Mawson P.,University of Western Australia |
Mawson P.,0 Labouchere Road |
Maloney S.K.,University of Western Australia
Journal of Pharmacological and Toxicological Methods | Year: 2015
Introduction: Plasma cholinesterase activity levels of various species may be of interest to toxicologists or pathologists working with chemicals that interfere with the activity of plasma cholinesterase. Methods: We used a pH titration method to measure the plasma cholinesterase activity of six mammalian species. Results: Plasma cholinesterase activity varied up to 50-fold between species: sheep (88. ±. 45. nM acetylcholine degraded per ml of test plasma per minute), cattle (94. ±. 35), western grey kangaroos (126. ±. 92), alpaca (364. ±. 70), rats (390. ±. 118) and horses (4539. ±. 721). Discussion: We present a simple, effective technique for the assay of plasma cholinesterase activity levels from a range of species. Although labour-intensive, it requires only basic laboratory equipment. © 2015 Elsevier Inc.
Tapley B.,Zoological Society of London |
Bradfield K.S.,0 Labouchere Road |
Michaels C.,Zoological Society of London |
Bungard M.,Paignton Zoo
Biodiversity and Conservation | Year: 2015
Amphibians are facing an extinction crisis, and conservation breeding programmes are a tool used to prevent imminent species extinctions. Compared to mammals and birds, amphibians are considered ideal candidates for these programmes due to their small body size and low space requirements, high fecundity, applicability of reproductive technologies, short generation time, lack of parental care, hard wired behaviour, low maintenance requirements, relative cost effectiveness of such programmes, the success of several amphibian conservation breeding programmes and because captive husbandry capacity exists. Superficially, these reasons appear sound and conservation breeding has improved the conservation status of several amphibian species, however it is impossible to make generalisations about the biology or geo-political context of an entire class. Many threatened amphibian species fail to meet criteria that are commonly cited as reasons why amphibians are suitable for conservation breeding programmes. There are also limitations associated with maintaining populations of amphibians in the zoo and private sectors, and these could potentially undermine the success of conservation breeding programmes and reintroductions. We recommend that species that have been assessed as high priorities for ex situ conservation action are subsequently individually reassessed to determine their suitability for inclusion in conservation breeding programmes. The limitations and risks of maintaining ex situ populations of amphibians need to be considered from the outset and, where possible, mitigated. This should improve programme success rates and ensure that the limited funds dedicated to ex situ amphibian conservation are allocated to projects which have the greatest chance of success. © 2015, Springer Science+Business Media Dordrecht.