 In 2017 the Australian ornithologist Joseph M. Forshaw found it hard to accept that all the illustrations that showed the colour as brown were wrong; he found it more likely that the brown would have merely faded in intensity rather than from grey to brown.He stated that by the time the earliest known illustrations of the bird were made, it is unlikely they would already have faded to brown because of exposure to light.He also doubted that poor diet of caged birds would have consistently turned them brown, and instead accepted the "orthodox image" of the bird as brown.