Comment from Schmuck, Lauren

We (Lauren Schmuck and Alex Berryman) conducted an assessment to determine whether the Eskimo Curlew meets the criteria to be listed as extinct on the IUCN Red List, using two IUCN-endorsed approaches: (1) a threats-based analysis and (2) a records-and-surveys analysis. The threats model evaluated the severity, duration, and geographic extent of major threats, including unsustainable hunting, habitat loss, reduced prey availability, and some other more minor threats. It generated a probability of extinction of 0.76–0.97 (best estimate: 0.91). Please note that the results of this model should be considered preliminary until published in the peer-reviewed literature. The records-and-surveys model incorporated 419 historical records and more than five decades of targeted surveys, structured monitoring programs, and citizen-science observations across the species' range. This analysis generated a probability of extinction of 0.546–0.999 (best estimate: 0.932). Please note that the results of this model should be considered preliminary until published in the peer-reviewed literature. The estimates generated by both models exceed the IUCN threshold (greater than or equal to 0.90) for listing a species as Extinct. A Bayesian analysis (Solow & Beet model) of sighting records indicated that extinction most likely occurred around 1969, shortly after the last confirmed record in 1963. Based on these results, our forthcoming publication will recommend listing Numenius borealis as Extinct on the IUCN Red List, and under applicable national legislation and international conventions.