Tell-tale testicles: observations of morphological abnormalities in small, spatially restricted mainland quokka (Setonix brachyurus) populations

2019 ◽  
Vol 41 (1) ◽  
pp. 150
Author(s):  
Shannon J. Dundas

The quokka (Setonix brachyurus) exists in spatially restricted populations in the northern jarrah forest in south-west Western Australia. Observations were made of adult male quokkas exhibiting morphological anomalies (cryptorchidism and micropthalmia) that may be indicative of inbreeding within these populations. Despite the presence of males with abnormalities that could potentially affect their fertility, most females captured were carrying a pouch young or feeding a joey at foot. Field researchers and managers should routinely report abnormalities seen in wild captured animals. Reduced genetic diversity of quokka populations in the northern jarrah forest may not be the key threatening process and preservation of habitat may be more important to ensure persistence of populations. Future management of this species in the northern jarrah forest should include up-to-date occurrence mapping across their range using targeted camera trap surveys and management of habitat to improve connectivity between populations.

2002 ◽  
Vol 50 (6) ◽  
pp. 769 ◽  

The fungicide phosphite was shown to affect pollen fertility in a range of perennial species from the south-west of Western Australia. Phosphite was applied to perennial species of the jarrah (Eucalyptus marginata) forest by spraying to run-off with 2.5, 5 and 10 g L–1 phosphite in either autumn or spring. Pollen fertility of Dryandra sessilis was reduced by phosphite for up to 35 and 60 weeks after spraying in spring or autumn, respectively. Trymalium ledifolium pollen fertility was reduced by phosphite 38 and 61 weeks after spraying in spring or autumn, respectively. Lasiopetalum floribundum was less affected with a reduction in pollen fertility being observed for up to 3 weeks after spraying in spring. Other perennial understorey species of the jarrah forest, Adenanthos barbiger, Boronia cymosa, Hovea elliptica and Phyllanthus calycinus were also shown to have reduced pollen fertility after treatment in autumn or spring, as did Comesperma calymega, Eremaea astrocarpa and Hibbertia hypericoides, species of the northern sandplains when sprayed in summer.


2014 ◽  
Vol 41 (2) ◽  
pp. 117 ◽  
Author(s):  
Shannon J. Dundas ◽  
Peter J. Adams ◽  
Patricia A. Fleming

Context In Western Australia, baits containing 1080 poison are widely used to control the red fox (Vulpes vulpes) for fauna conservation. Despite long-term (15–17 years) baiting programs, bait uptake by target and non-target species is largely unknown, but affects baiting efficacy. Aims We examined bait uptake of 1080-poisoned fox baits laid according to current practice at seven riparian sites in the northern jarrah forest (of south-west Western Australia). There, intensive baiting regimes have been implemented for the protection of quokka (Setonix brachyurus) populations. Methods Over 9 months, 299 Probait® baits were monitored regularly to determine their persistence, and, at 142 of these, Reconyx HC500 remote cameras were used to identify the species taking baits. To compare bait uptake with species presence at these sites, we calculated an activity index for each species from the number of passes of animals in front of the cameras. Key results The species taking baits was identified for 100 of the baits monitored with cameras, and, because of multiple species taking baits, 130 bait take incidents were recorded in total. The fate of 40 of the baits was not discernible and two baits were not removed. In all, 99% of baits monitored by cameras were taken by non-target species and quokkas took 48% of them. The majority of baits (62% of the total 299 monitored) were taken before or on the first night of deployment, and 95% of baits had been taken within 7 days. With the exception of feral pigs, which took more baits than predicted from their activity index at these sites, baits were taken in proportion to the activity index of species. Foxes were present at four of the seven sites, but only one fox was observed taking a bait. Conclusions The high level of uptake of baits by non-target animals reflects their diversity and abundance at these sites, but also significantly reduces the availability of baits to control foxes. Implications Strategies to reduce non-target bait uptake and increase bait availability for foxes are required.


2001 ◽  
Vol 7 (2) ◽  
pp. 101 ◽  
Author(s):  
Ian Abbott ◽  
Allan Wills

A theory proposed in 1996 by Recher, Majer and Ganesh linking biodiversity of forest canopy arthropods to site productivity is analysed. Available evidence from Jarrah Eucalyptus marginata forest is inconsistent with this model. We instead propose that increased habitat variety and temperature and rainfall clines are the major environmental factors that determine canopy arthropod species richness. Biodiversity gradients for mammal, landbird and reptile species across south-west Western Australia appear to provide an appropriate model for forest insect faunas. These gradients predict that the most diverse canopy fauna should occur in the eastern Jarrah and Wandoo forests. Precautionary forest management policies and procedures currently in place to conserve the poorly collected and inadequately known arthropod fauna of tree crowns in Jarrah forest are summarized and discussed. In essence, these maximize habitat diversity at landscape scales. Major conservation threats are considered to be factors that reduce leaf area at large spatial (Phytophthora infection) and temporal scales (summer wildfire and defoliating insect outbreaks). Logging is not considered significant because it is constrained to small spatial scales (10 ha for the most extreme treatment) and long return times (2-3 decades).


2007 ◽  
Vol 47 (7) ◽  
pp. 883 ◽  
Author(s):  
Rob Manning ◽  
Kate Lancaster ◽  
April Rutkay ◽  
Linda Eaton

The parasite, Nosema apis, was found to be widespread among feral populations of honey bees (Apis mellifera) in the south-west of Western Australia. The location, month of collection and whether the feral colony was enclosed in an object or exposed to the environment, all affected the presence and severity of infection. There was no significant difference in the probability of infection between managed and feral bees. However, when infected by N. apis, managed bees appeared to have a greater severity of the infection.


2020 ◽  
Vol 37 (1) ◽  
pp. 38-45
Author(s):  
O.A. Okukenu ◽  
A.A. Olajide ◽  
P.A. Dele ◽  
M. Wheto ◽  
B.T. Akinyemi ◽  
...  

This study was carried out to characterise Pennisetum purpureum harvested from some selected locations in S outh-W estern Nigeria using microsatellite markers. Leaf parts of growing young elephant grass (Pennisetum purpureum) were harvested and immediately preserved in ethanol solution before DNA extraction. Two (2) SSR primers (CTM59 and Xtxp278) were used to assess genetic diversity in Pennisetum purpureum. The result shows that 72% of the molecular variations in the elephant grass exists within the population with 28% among the population; there were no unique characteristics among the Nine (9) populations. Nei genetic index ranged from 0.067 (lowest) observed between Isokan and Odeda populations to 0.158 (highest), between Ifedore and Ikoyi Populations. Morphological characterization showed moderate diversity with two major clusters and one minor cluster. Keyword: Elephant grass; cultivars; locations; markers


Author(s):  
David Worth

Over the past 30 years in Western Australia (WA), there has been heated debate about the future use of the remaining karri and jarrah forests in the south-west of the State. This debate revolves around policy proposals from two social movements: one wants to preserve as much of the remaining old-growth forests as possible, and an opposing movement supports a continued


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