Abstract
Birds, especially raptors, play important roles in ecosystems. We examine the International Union for the Conservation of Nature’s (IUCN) Red List to determine which orders of birds have proportionally more or fewer species listed as threatened or declining compared to the Class-wide average. We further examine whether raptors are more threatened or declining than non-raptors and whether the order Accipitriformes is particularly threatened even when excluding Old World vultures – which are especially imperiled. Our results reveal heterogeneity across bird orders in proportions of threatened and declining species, with some orders having greater or lower proportions than the Class-wide proportion. We also show that the proportions of threatened species in each order are correlated with the proportion of declining species. Raptors have both greater proportions of threatened and declining species than non-raptors and Accipitriformes has greater-than-average proportions of threatened and declining species, even if Old World vultures are removed from the analysis. Our results should serve as a framework for discussion of the relative conservation status of bird orders, especially raptors, which are in need of increased conservation attention.
Highlights
Earth is experiencing a sixth mass extinction – losing species at a rate thousands of times higher than between extinction events (Ceballos et al, 2010, 2015)
Such bird declines lessen ecosystem function (Sekercioglu et al, 2004), because birds play important roles including as pollinators, dispersers, scavengers, and predators (Whelan et al, 2008)
To determine what the distribution of threatened species would be if those species were distributed randomly across orders, we drew the number of threatened species at random from the full list of species and noted which orders the randomly-drawn species were within
Summary
Earth is experiencing a sixth mass extinction – losing species at a rate thousands of times higher than between extinction events (Ceballos et al, 2010, 2015). Since the year 1500, a minimum of 159 species of birds have gone extinct and many populations of extant species have been lost (Ceballos et al, 2017; BirdLife International, 2019). Even common species are experiencing declines (Ceballos et al, 2017), with bird populations declining by an estimated 29% across North America declining since 1970 (Rosenberg et al, 2019). Such bird declines lessen ecosystem function (Sekercioglu et al, 2004), because birds play important roles including as pollinators, dispersers, scavengers, and predators (Whelan et al, 2008). Turkey Vultures (Cathartes aura) provide an estimated $700 million in ecosystem services by consuming roughly 1,000 tons of carrion per year (Grilli et al, 2019)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
