However, the decline in 2-ha 20-min surveys from 1999–2019 (8,987 individuals 267,885 surveys) was only 15% (BirdLife Australia 2020). 2002), including a decline of 44% in New South Wales (Barrett et al. This follows a significant decline of 22% between 1977–19–2001 (Barrett et al. Reporting rates from 500-m radius area searches (20,094 individuals 328,201 surveys), arguably the most reliable of the available survey methods for the species, declined by 69% from 1999–2019. Apart from fire impacts, trend data are not entirely consistent. It is estimated that the 2019–2020 fire season reduced the carrying capacity of 40% of grid cells by half and resulted in 10% mortality (Cameron et al. Combining these measures and uncertainty creates a likely population estimate of between 17,600 and 35,200 mature individuals, with a most likely figure (the midpoint) of 25,300. The density applied assumes an average density of 3.1 birds/km 2, that the 2019–2020 fire season reduced the carrying capacity of 40% of grid cells by half and resulted in 10% mortality (Cameron et al. (2021), the smallest being the number of 2x2 km squares for which there are records since 1990, the latter being an arbitrary value of nearly double this to account for incomplete survey effort of potentially suitable habitat. Population justification The estimate used here is the product of three predicted AOO measures (spanning 22,700-40,000 km 2) from Cameron et al. For these reasons the species is assessed as Vulnerable. Geobot.Justification of Red List category Despite this species having a large range, reporting rates and the impacts of recent fires indicate rapid population declines in the last three generations, and this decline is likely to continue with climate change projections. 2005] Ecomorphological diversificatio.Amur Falcon Falco amurensis Massacre i. 2012] the World's Rarest Whale | Spade.2012] Food preference of Malagasy fru.Sunda Stink-badger, Mydaus javanensis.CITES CoP16 | 16th Meeting of the Conference of th. When the molecular evidence is analysed in concert with morphology, it is clear that many of the cockatoo species’ diagnostic phenotypic traits such as plumage colour, body size, wing shape and bill morphology have evolved in parallel or convergently across lineages. A detailed multi-locus molecular phylogeny enabled us to resolve the phylogenetic placements of the Palm Cockatoo ( Probosciger aterrimus), Galah ( Eolophus roseicapillus), Gang-gang Cockatoo ( Callocephalon fimbriatum) and Cockatiel ( Nymphicus hollandicus), which have historically been difficult to place within Cacatuidae. We hypothesize that this environmental transformation was a driving force behind the diversification of cockatoos. The early to middle Miocene (20–10 Ma) was a significant period in the evolution of modern Australian environments and vegetation, in which a transformation from mainly mesic to xeric habitats (e.g., fire-adapted sclerophyll vegetation and grasslands) occurred. Our data shows Cacatuidae began to diversify approximately 27.9 Ma (95% CI 38.1–18.3 Ma) during the Oligocene. In addition, five novel mitochondrial genomes were used to estimate time of divergence and our estimates indicate Cacatuidae diverged from Psittacidae approximately 40.7 million years ago (95% CI 51.6–30.3 Ma) during the Eocene. We investigated the phylogeny of cockatoos based on three mitochondrial and three nuclear DNA genes obtained from 16 of 21 species of Cacatuidae. However, the evolutionary history of cockatoos is not well understood. Cockatoos are the distinctive family Cacatuidae, a major lineage of the order of parrots (Psittaciformes) and distributed throughout the Australasian region of the world.
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