School of Earth & Environmental Science
Vickers, Jacob A T, Demographic shifts in Noisy Miner (Manorina melanocephala) populations following removal, BEnviSc Hons, School of Earth & Environmental Science, University of Wollongong, 2017.
The increasing abundance of Noisy Miners (Manorina melanocephala) represents a large threat to avifaunal assemblages throughout eastern Australia. Their hyper-aggressive colonial social structure has a negative effect on many already threatened small birds, including the critically endangered Regent Honeyeater (Anthochaera Phrygia) and the endangered Swift Parrot (Lathamus discolour). Their increased abundance has consequently been listed as a Key Threatening Process under both state and federal legislation. Culling has been used successfully to reduce the impacts of Noisy Miners and has been suggested as a threat abatement action, however, recolonisation has sometimes been observed. This project aimed to investigate the effects of culling on the demographics of recolonists, to determine the source of recolonists, and thereby improve our understanding of the circumstances when culling may be successful. Additionally, I assessed the efficacy of an ageing technique, and developed a reliable method for sexing Noisy Miners non-destructively. I found that; a) the shape of the alula is not a reliable sexing criterion, b) 90% of Noisy Miners can be correctly assigned a sex using morphometric data, and c) the source of recolonists varied according to the season of the cull, based on the availability of individuals within the landscape. Dispersing immatures comprised the majority of recolonists following the breeding season, whilst matures from neighbouring colonies provided the majority of recolonists beforehand. These findings demonstrate that the time of culling has a significant effect on the type of recolonisation and can be used to assist the development of an effective threat abatement plan.