{"title":"The impact of a mega-fire on tree hollow loss and nest box occupancy by secondary cavity-nesting cockatoos","authors":"Karleah Kyrene Berris, Michael Barth, Torran Welz","doi":"10.1111/aec.13565","DOIUrl":null,"url":null,"abstract":"<p>Tree hollows are important structural habitat features for secondary cavity-nesting birds, however, there has been limited research on how fire severity and frequency affect hollow abundance. Following a mega-fire on Kangaroo Island during the 2019–2020 Australian bushfire season, we conducted an opportunistic post-fire assessment of the fate of 144 monitored hollows in <i>Eucalyptus cladocalyx</i> and <i>Eucalyptus leucoxylon</i> trees used by endangered glossy black-cockatoos (<i>Calyptorhynchus lathami halmaturinus</i>) and yellow-tailed black-cockatoos (<i>Zanda funerea</i>). We investigated the relationship between burn severity, inter-fire interval, tree species and landscape position on the likelihood of tree hollow loss. We also compared the occupancy of nest boxes by both cockatoo species in fire-affected catchments pre-fire (2015–2017; 59 nest boxes) and post-fire (2020–2022; 52 nest boxes). Surveys revealed that 64.4% of monitored tree hollows within the burnt area were destroyed, as were the trees that contained them. Most monitored tree hollows (76.9%) were in areas that had not experienced fire in >50 years prior to the 2019–2020 fires. Tree hollow loss in 2020 was 29 times greater than the mean annual loss of 1.6% recorded in the 22 years prior. Burn severity, inter-fire interval, landscape matrix and tree species were poor predictors of hollow loss. However, increasing distance from forest edge slightly increased the probability of hollow loss. Post-fire, the proportion of nest boxes used for nesting by glossy black-cockatoos per annum increased to 0.70 ± 0.09, compared to 0.50 ± 0.03 pre-fire. However, the proportion of nest boxes used for nesting by yellow-tailed black-cockatoos per annum remained similar (post-fire 0.32 ± 0.12; pre-fire 0.28 ± 0.05). The mega-fires on Kangaroo Island in 2019–2020 resulted in tree hollow loss on a much larger scale than recorded in the 22 years prior, and subsequently, nest boxes have become an important resource for the endangered glossy black-cockatoo.</p>","PeriodicalId":8663,"journal":{"name":"Austral Ecology","volume":"49 7","pages":""},"PeriodicalIF":1.6000,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Austral Ecology","FirstCategoryId":"93","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1111/aec.13565","RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ECOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Tree hollows are important structural habitat features for secondary cavity-nesting birds, however, there has been limited research on how fire severity and frequency affect hollow abundance. Following a mega-fire on Kangaroo Island during the 2019–2020 Australian bushfire season, we conducted an opportunistic post-fire assessment of the fate of 144 monitored hollows in Eucalyptus cladocalyx and Eucalyptus leucoxylon trees used by endangered glossy black-cockatoos (Calyptorhynchus lathami halmaturinus) and yellow-tailed black-cockatoos (Zanda funerea). We investigated the relationship between burn severity, inter-fire interval, tree species and landscape position on the likelihood of tree hollow loss. We also compared the occupancy of nest boxes by both cockatoo species in fire-affected catchments pre-fire (2015–2017; 59 nest boxes) and post-fire (2020–2022; 52 nest boxes). Surveys revealed that 64.4% of monitored tree hollows within the burnt area were destroyed, as were the trees that contained them. Most monitored tree hollows (76.9%) were in areas that had not experienced fire in >50 years prior to the 2019–2020 fires. Tree hollow loss in 2020 was 29 times greater than the mean annual loss of 1.6% recorded in the 22 years prior. Burn severity, inter-fire interval, landscape matrix and tree species were poor predictors of hollow loss. However, increasing distance from forest edge slightly increased the probability of hollow loss. Post-fire, the proportion of nest boxes used for nesting by glossy black-cockatoos per annum increased to 0.70 ± 0.09, compared to 0.50 ± 0.03 pre-fire. However, the proportion of nest boxes used for nesting by yellow-tailed black-cockatoos per annum remained similar (post-fire 0.32 ± 0.12; pre-fire 0.28 ± 0.05). The mega-fires on Kangaroo Island in 2019–2020 resulted in tree hollow loss on a much larger scale than recorded in the 22 years prior, and subsequently, nest boxes have become an important resource for the endangered glossy black-cockatoo.
期刊介绍:
Austral Ecology is the premier journal for basic and applied ecology in the Southern Hemisphere. As the official Journal of The Ecological Society of Australia (ESA), Austral Ecology addresses the commonality between ecosystems in Australia and many parts of southern Africa, South America, New Zealand and Oceania. For example many species in the unique biotas of these regions share common Gondwana ancestors. ESA''s aim is to publish innovative research to encourage the sharing of information and experiences that enrich the understanding of the ecology of the Southern Hemisphere.
Austral Ecology involves an editorial board with representatives from Australia, South Africa, New Zealand, Brazil and Argentina. These representatives provide expert opinions, access to qualified reviewers and act as a focus for attracting a wide range of contributions from countries across the region.
Austral Ecology publishes original papers describing experimental, observational or theoretical studies on terrestrial, marine or freshwater systems, which are considered without taxonomic bias. Special thematic issues are published regularly, including symposia on the ecology of estuaries and soft sediment habitats, freshwater systems and coral reef fish.