School of Biological Sciences, University of Sydney, Sydney, NSW, Australia.
PLoS One. 2013;8(3):e59332. doi: 10.1371/journal.pone.0059332. Epub 2013 Mar 21.
Urbanisation typically results in a reduction of hollow-bearing trees and an increase in the density of particularly species, potentially resulting in an increased level of competition as cavity-nesting species compete for a limited resource. To improve understanding of hollow usage between urban cavity-nesting species in Australia, particularly parrots, we investigated how the hollow-using assemblage, visitation rate, diversity and number of interactions varied between hollows within urban remnant forest and continuous forest. Motion-activated video cameras were installed, via roped access to the canopy, and hollow usage was monitored at 61 hollows over a two-year period. Tree hollows within urban remnants had a significantly different assemblage of visitors to those in continuous forest as well as a higher rate of visitation than hollows within continuous forest, with the rainbow lorikeet making significantly more visitations than any other taxa. Hollows within urban remnants were characterised by significantly higher usage rates and significantly more aggressive interactions than hollows within continuous forest, with parrots responsible for almost all interactions. Within urban remnants, high rates of hollow visitation and both interspecific and intraspecific interactions observed at tree hollows suggest the number of available optimal hollows may be limiting. Understanding the usage of urban remnant hollows by wildlife, as well as the role of parrots as a potential flagship for the conservation of tree-hollows, is vital to prevent a decrease in the diversity of urban fauna, particularly as other less competitive species risk being outcompeted by abundant native species.
城市化通常会导致空心树的减少和特定物种密度的增加，这可能导致腔巢物种为有限的资源而竞争加剧。为了更好地了解澳大利亚城市腔巢物种（特别是鹦鹉）之间的空心使用情况，我们调查了城市残余森林和连续森林中空心的使用组合、访问率、多样性和相互作用的数量如何变化。通过绳索进入树冠，安装了运动激活的摄像机，并在两年内监测了 61 个空心的使用情况。城市残余物中的树洞与连续森林中的树洞相比，访客的组合有明显的不同，访问率也高于连续森林中的树洞，彩虹吸蜜鹦鹉的访问量明显高于任何其他分类群。城市残余物中的树洞的使用率明显更高，与连续森林中的树洞相比，攻击性相互作用也明显更多，而鹦鹉几乎负责所有的相互作用。在城市残余物中，树木空心的空心访问率和种间和种内相互作用都很高，这表明可用的最佳空心数量可能有限。了解野生动物对城市残余空心的使用情况，以及鹦鹉作为保护树洞的潜在旗舰物种的作用，对于防止城市动物多样性的减少至关重要，特别是因为其他竞争力较弱的物种可能会被丰富的本地物种所竞争。
