Monitoring threats to Australian threatened birds: climate change was the biggest threat in 2020 with minimal progress on its management

Most biodiversity monitoring globally tends to concentrate on trends in species’ populations and ranges rather than on threats and their management. Here we review the estimated impact of threats and the extent to which their management is understood and implemented for all threats to all Australian threatened bird taxa. The assessment reports the situation in 2020 and how this differs from 2010. The most marked finding was that the impact of climate change has increased greatly over the last decade, and now surpasses invasive species as the threat imposing the heaviest threat load. Climate change has driven recent massive population declines from increased temperatures in tropical montane rainforests and from fire. For both direct climate change impacts and fire management, progress in understanding how to relieve the threats has been slow and patchy. Consequently, little effective management has occurred. By comparison, our analysis showed that the single successful campaign to eradicate introduced mammals from Macquarie Island relieved the total threat load on Australian threatened birds by 5%, and more than halved the load on the birds from oceanic islands. Protection or rehabilitation of habitat, particularly on islands, has also delivered measurable benefit as have, in the longer term, controls on longline fishing. Our approach can be used with other taxonomic groups to understand progress in research and management and to allow quantification of potential benefits from proposed actions, such as the national threatened species plan. Climate change is now the biggest threat to Australian threatened birds, but almost no research or management to mitigate this threat has been undertaken.Most successful threatened species management has been on small islands with invasive species eradication, habitat protection and restoration providing substantial benefits.The approach taken can be used to quantify the benefits of both past conservation interventions and potential interventions.Monitoring trends in threat load complements indices assessing trends in population size and extinction risk. Climate change is now the biggest threat to Australian threatened birds, but almost no research or management to mitigate this threat has been undertaken. Most successful threatened species management has been on small islands with invasive species eradication, habitat protection and restoration providing substantial benefits. The approach taken can be used to quantify the benefits of both past conservation interventions and potential interventions. Monitoring trends in threat load complements indices assessing trends in population size and extinction risk.

全球多数生物多样性监测（biodiversity monitoring）往往聚焦于物种种群与分布范围的变化趋势，而非威胁因素及其管理措施。本研究针对澳大利亚所有受胁鸟类类群的各类威胁，综述了其预估影响，以及当前对这些威胁的认知与管理落实程度。本次评估报告了2020年的现状，并对比了其与2010年的差异。

最显著的发现是，过去十年间气候变化的影响大幅加剧，如今已超越入侵物种，成为造成最重威胁负荷（threat load）的因素。气候变化通过热带山地雨林地区的升温以及火灾事件，推动了近期种群的大规模下降。在直接气候变化影响与火灾管理两方面，人们对如何缓解威胁的研究进展均缓慢且不均衡，因此鲜有有效的管理措施落地。

相比之下，我们的分析显示，从麦夸里岛（Macquarie Island）根除入侵哺乳动物的单次成功行动，使澳大利亚受胁鸟类面临的总威胁负荷降低了5%，并使海洋岛屿上鸟类面临的威胁负荷减少了一半以上。栖息地保护与修复（尤其是在岛屿上）也带来了可量化的益处，长期来看，延绳钓捕鱼管控亦起到了类似效果。

本研究方法可应用于其他生物分类类群，以研判其研究与管理进展，并量化诸如国家受胁物种计划等拟议措施所能带来的潜在效益。目前气候变化已是澳大利亚受胁鸟类面临的最大威胁，但几乎未开展任何针对该威胁的减缓研究与管理工作。

大部分成功的受胁物种管理实践均针对小型岛屿，通过入侵物种根除、栖息地保护与修复可带来显著效益。本研究所采用的方法可用于量化过往保护干预措施与潜在干预措施所能带来的效益。监测威胁负荷的变化趋势，可作为评估种群规模与灭绝风险（extinction risk）变化趋势的指标的有益补充。

气候变化目前仍是澳大利亚受胁鸟类面临的最大威胁，但几乎未开展任何针对该威胁的减缓研究与管理工作。多数成功的受胁物种管理实践均聚焦于小型岛屿，通过入侵物种根除、栖息地保护与修复可获得可观效益。本研究采用的方法可量化过往保护干预举措与潜在干预举措所能带来的效益。对威胁负荷变化趋势的监测，可作为评估种群规模与灭绝风险变化趋势的指标的有效补充。