Gang-gang Hollow Search study already yielding results.

Thanks to Katie, Chris, Matt, Amber and Susan for their identification and monitoring of nests in Campbelltown and Moruya where Gang-gang chicks have already fledged. This is about 4-6 weeks ahead of the nesting occurring in the twenty observed nests in the Canberra area and one in Cooma (thanks Ange). In terms of the Gang-Gangs total range, Campbelltown and Moruya are at the higher latitude and or lower altitude parts of this range. Thus they achieve higher temperatures than most areas in which Gang-gangs occur.

Peter and Judy Smith in their 2018 Gang-gang survey of Hornsby Shire, (https://www.researchgate.net/publication/340599663), failed to record any Gang-gangs in areas where from 1970-2010 they were commonly sighted. They concluded that Gang-gangs in the Hornsby and Ku-ring-gai Local Government Areas are certainly very close to extinction if not already extinct. They noted that a similar decline had occurred within a 20km radius of their study area and at the lower elevations of the Blue Mountains. They proposed that this pattern of decline suggests a climate change effect. They noted that the Gang-gang is adapted to cooler conditions and has always been more common at higher elevations and more southern latitudes. They hypothesized that as the climate warms up, Gang-gang Cockatoos can be expected to decline at lower elevations in the northern parts of their distribution.

A result of our citizen science study suggests that Gangs-gangs in at least part of the northern lower elevation range may be able to avoid the higher summer temperatures by breeding earlier than more elevated or southern birds. This is a hopeful finding, that will need further investigation.

Some of you are also watching nests in Tumbarumba, on the outskirts of Melbourne and in western Victoria – none of which appear yet to have produced fledglings. Fingers crossed you will be able to observe fledglings and you will add to our knowledge of breeding times across the Gang-gangs range. Now that there is a large band of us looking for nests, we can expect that next season we will have the range well covered.

In addition to climate, the Smith’s mentioned other factors that may be contributing to the decline including competition with other species for nest hollows (particularly the over-abundant Sulphur-crested Cockatoos and Rainbow Lorikeets). Our study is also throwing light on this issue – but reporting of these initial results is for the next Journal report.

Posted by michaelmulvaney michaelmulvaney, December 18, 2021 08:20 PM

Comments

Thank you for undertaking the study.

Another factor that may be affecting the availability of appropriate tree hollows for nests would be the feral European bee. They are assessed to be a key threatening process for a number of endangered species in NSW.

European bee swarms take over tree hollows and exclude or kill the native species.

The NSW the Scientific Committee made a final determination that the European honey bees be listed as a key threatening process under endangered species legislation https://www.environment.nsw.gov.au/topics/animals-and-plants/threatened-species/nsw-threatened-species-scientific-committee/determinations/final-determinations/2000-2003/competition-from-feral-honeybees-key-threatening-process-listing

The WA Museum also outlines the problem.http://museum.wa.gov.au/explore/online-exhibitions/cockatoo-care/feral-bees

Posted by katyw about 1 year ago (Flag)

Thanks Katyw - as detailed in my next post you are right, bees are a factor - we found them occupying 3% of the hollows that sometime in the previous three seasons Gang-gangs had either used as a nest hollow or where observed entering/leaving, chewing bark around or looking into.

Posted by michaelmulvaney about 1 year ago (Flag)

Add a Comment

Sign In or Sign Up to add comments