Update on the Ivory-billed Woodpecker (Campephilus principalis) Scandal

Abstract

The Ivory-billed Woodpecker (Campephilus principalis) is an elusive bird that has repeatedly been feared extinct only to be rediscovered during the past hundred years. The most recent rediscovery, which took place in Arkansas, was announced in an article that was featured on the cover of Science in 2005. Despite published reports of sightings in Florida and Louisiana in the years that followed, the issue became controversial when nobody managed to obtain a clear photo and critics attacked relatively weak video evidence that was presented in the original article. The issue began to develop into a science scandal when the critics used specious arguments to delay the publication of the strongest evidence, which consists of three videos that were obtained during encounters with birds that were identified in the field as Ivory-billed Woodpeckers and that show field marks, body proportions, flights, and other behaviors that are consistent with that species but no other species of the region. The scandal culminated in a decision by the U.S. Fish & Wildlife Service to declare the species extinct in 2021, which was made without addressing the strongest evidence. An update is given here on recent developments. The decision to declare the species extinct was based on a five-year review of evidence for persistence. During an interview, it came to light that the person who performed the review was unaware of basic facts about the strongest evidence. Evidence that was obtained at another site in Louisiana [Latta et al., “Multiple lines of evidence suggest the persistence of the Ivory-billed Woodpecker (Campephilus principalis) in Louisiana,” Ecology and Evolution (2023)] is discussed and compared with the strongest evidence. Videos obtained with a drone on a sunny day often show white markings that do not correspond to actual field marks. It is demonstrated that a video that was purported to show an Ivory-billed Woodpecker on the basis of apparent white markings is apparently a Pileated Woodpecker (Dryocopus pileatus). The bird in that video appears to have black trailing edges on the dorsal surfaces of the wings, which are consistent with the Pileated Woodpecker, not the Ivory-billed Woodpecker. The wingbeat frequency and an upward swooping landing also seem to be consistent with the Pileated Woodpecker but are not consistent with historical accounts of the Ivory-billed Woodpecker or flights appearing in videos that contain the strongest evidence.