13 Dec 2019

7 things you might have missed from the 2019 Red List update

Every year, our scientists work around the clock to update the threat status of birds on the IUCN Red List of threatened species. While the amazing recovery of the Guam Rail might have taken centre stage, 2019 heralded plenty more important discoveries. From victims of climate change to exciting new information on unknown birds, here are the latest ups and downs of the avian world that might not have made the headlines.

The Greater Green Leafbird is now Endangered © vil.sandi / Flickr
The Greater Green Leafbird is now Endangered © vil.sandi / Flickr
By Cressida Stevens

1. The Asian songbird crisis deepens


The Asian pet bird trade spells trouble for many species, and if it’s not the birds’ good looks that put them in danger, it’s their beautiful singing voice. Besides their popularity as pets, they are highly sought after as contestants in bird song competitions. In 2012, a Greater Green Leafbird won the highly prestigious President Cup Bird Competition in Indonesia, sparking a huge demand for this species and other leafbirds. In this year’s update, the Greater Green Leafbird Chloropsis sonnerati, Sumatran Leafbird Chloropsis media and Javan Leafbird Chloropsis cochinchinensis have all been uplisted to Endangered.

Trappers are reporting that there are fewer around in the wild, making them harder to find – problematic for birds, but not so much for the trappers since a worrying trend shows that once supply of one dwindles, they move on to target a different species. The statuses of the Javan White-eye Zosterops flavus (Endangered), Pale-bellied Myna Acridotheres cinereus (Vulnerable) and Brown-cheeked Bulbul Alophoixus bres (Near Threatened) have all also deteriorated because of their appeal to pet owners. For a custom that is as culturally ingrained as dog ownership in the West, this cannot be resolved simply, and requires diplomatic discussion and education on the sides of both bird owners and conservationists.


2. New knowledge of under-studied bird species

Scientists are now beginning to understand Markham's Storm-petrel © Jaime Jahncke

How do we conserve and prioritise species that we know almost nothing about? There are 53 bird species listed as Data Deficient on the IUCN Red List, presenting a great challenge to conservation planning. However, our scientists are gradually whittling down this number. Often we lack information on species because they live in remote, unreachable places or because we simply don’t know where to find them. The latter was the case for Markham’s Storm-petrel Hydrobates markhami and the Ringed Storm-petrel Hydrobates hornbyi – after all, who would have guessed that these seabirds travel inland to breed in the driest place on earth, the Atacama Desert in northern Chile? According to the Neotropical Birding magazine, some petrels have been found here at 1,600 metres above sea level and Ringed Storm-petrels have been found as far as 75 kilometres away from the sea. Now that researchers have been able to track them down and assess them more carefully, they have been assigned a category for the first time - both Near Threatened.


3. The Bogotá Sunangel is not a real species

The final piece of the puzzle has fallen into place for the Bogotá Sunangel © HBW

One day, the Bogotá Sunangel Heliangelus zusii is a species in its own right, the next it is struck off the record. This bird is only known from one specimen found in Colombia, but following careful examination, scientists have now agreed that it is in fact a hybrid of two other species. You might call that an identity crisis and feel bad for the bird being shunted out of the species list, but really this is a positive outcome. Lacking observations of the bird meant that if it were indeed a species, it was probably extinct. However, both ‘parent’ species of the specimen – the Long-tailed Sylph Aglaiocercus kingii and either a Heliangelus or Metallura hummingbird – are still surviving, so that is one fewer species lost to us, and one more species off the Data Deficient list – we’ll call that good news.


4. Gurney’s Pitta now Critically Endangered

The habitat of Gurney’s Pitta is in danger of imminent destruction © Boonchuay Promijam

You might remember this colourful bird as one of our Lazarus birds, the one that was lost, then found, then lost again. A gripping, but tragic story - for over 30 years, it was thought extinct, until 1986, when it was spotted in Thailand in five separate locations. But soon after, their numbers fell flat, and with a mere 9 pairs it was deemed to be one of earth’s rarest species. Hope was renewed yet again in 2003 when thousands of breeding pairs were discovered in Myanmar. But unfortunately, the rollercoaster saga continues still. The habitat of the Gurney’s Pitta Hydrornis gurneyi is now in danger of imminent destruction and the bird is now Critically Endangered.


5. Birds' threat statuses rising with climate change

In 2017, Hurricane Maria reduced the Imperial Amazon's population to an estimated 40-60 individuals © HBW

The Imperial Amazon Amazona imperialis, endemic to Dominica, has had a rough time at the hands of humans. First it suffered declines due to habitat destruction and trapping. Although these issues have been addressed in part, the bird finds no respite and the species is now Critically Endangered, partly due to climate change. The species is significantly jeopardized by extreme weather, most dramatically in 2017 when Hurricane Maria (the strongest storm recorded to have hit Dominica to date) is thought to have reduced their population to around 40-60 individuals. Climate change is also a problem for the Black Rail Laterallus jamaicensis, a bird native to the Americas, which can only breed in shallow waters of less than 8cm deep. Within decades, rising sea levels and flooding is likely to exclude them from substantial parts of their range. For this reason, the Black Rail has been uplisted to Endangered.


6. Black-capped Vireo no longer threatened thanks to conservation action

The Black-capped Vireo has been moved to Near Threatened © Isaac Sanchez / Flickr

If only this bird’s distinctive spectacles could help it distinguish between its own young and that of the Brown-headed Cowbird Molothrus ater. The cowbird is notorious for depositing its eggs in other birds’ nests in a cuckoo-like fashion leading unwitting parents to care for cowbird chicks at the expense of their own young. For the Black-capped Vireo Vireo atricapilla, it had suffered this trick to such an extent that it was listed under the US Endangered Species Act in 1987, prompting the introduction of a cowbird control program. This response has been so successful that the vireo’s nest success has been rising and its Red List status falling. Following its downlisting from Endangered to Vulnerable in 2000, this year the species has been downlisted again from Vulnerable to Near Threatened, another inspiring example of conservation measures paying off.


7. More hope for the Cerulean Warbler

Earlier this year, we brought you encouraging news that the dramatic declines of this iconic warbler had slowed. Like the Black-capped Vireo, this bird too, has long suffered from the Brown-headed Cowbird’s troublesome tricks, as well as habitat destruction. Now, their steadying numbers have resulted in this beautiful bird moving from Vulnerable to Near Threatened giving its admirers a more tangible cause for celebration. Yet although the outlook has improved, the global population of the Cerulean Warbler Setophaga cerulea continues to decline, albeit more slowly, so we must keep a watchful eye on this flitting flash of blue.


Read more Red List stories here