Australian threatened birds for which the risk of extinction declined between 1990 and 2020.

Reducing extinction risk is a common aim of threatened species management. However, over the period 1990 to 2020, extinction risk was recently assessed as having declined in only 25 out of the 199 Australian bird taxa eligible for assessment. Here we analyse patterns that emerge from these taxa. Some of these improvements may be only temporary; the extinction risk of three taxa increased after it had initially declined. Invasive predator control on islands was the conservation intervention with greatest impact, benefitting 13 taxa (with nine of these from Macquarie Island). For four taxa, intensive management was the primary driver of reduced risk. Another four benefited from habitat protection and one from law enforcement. For seven taxa, conservation actions had no discernible effect; for two albatrosses a shift in fishing patterns may have reduced bycatch, for one, losses on the mainland meant that most birds now persist only in a stable island population and, for four taxa, reasons for changes in population trend are unknown. Never was there only one driver of reduced extinction risk with most taxa benefitting from at least five drivers. Macquarie Island was the only geographic cluster of taxa; there was little overlap among other taxa. Although the number of improvements is small, our results demonstrate that reduced extinction risk can be achieved with the right combination of targeted actions and, in some cases, serendipity. However, due to insufficient data, our ability to predict accurately the drivers of, or changes in, extinction risk for most species remains poor. Reductions in extinction risk are rare but achievable. Up to ten different factors contributed to reduced extinction risk in a taxon; there were rarely fewer than five. Extinction risk reduction had no geographical focus apart from the cluster of taxa on Macquarie Island. There is currently no widely accepted approach to classifying the many ways in which extinction risk can be reduced. Over a quarter of risk reduction examples were not the result of conservation interventions. [ABSTRACT FROM AUTHOR]