In 2022 an ornithologist high in the Sierra Nevada de Santa Marta mountains of northern Colombia spotted the shimmering emerald green and cobalt blue feathers of the Santa Marta sabrewing.

A large hummingbird it had only been documented twice since 1879. As the bird sat on a branch the ornithologist Yurgen Vega captured images.

Once lost to science it now was found. The bird was on the American Bird Conservancy’s 10 most wanted list which sits atop a longer register of lost birds which are formally defined as not having been documented by photographic audio or genetic evidence in at least a decade.

A major goal of the list is to persuade bird watchers and others to look for these birds as they go out into the field and to bring back evidence the birds have not gone extinct.

People have searched for lost birds for decades. But the process was formalized in 2020 by the conservancy in partnership with two other groups Re:wild and BirdLife International as the Search for Lost Birds project.

Researchers from the groups published a paper in June with a definitive list of birds that need finding.

They scoured tens of millions of photos videos and audio recordings in birding databases such as iNaturalist and xeno canto.

The study concluded that there are 144 species of bird lost to the scientific world but that may still exist.

Through more exposure in global ornithological and birding networks there’s great potential to learn more about birds that are poorly known and highly threatened said Cameron Rutt the lead author of the paper who coordinated the project for the American Bird Conservancy until recently.

Once the birds are documented experts analyze how they can be protected and studied. Since the rediscovery of Santa Marta sabrewings for instance researchers have been studying the bird’s habitat needs and biology and recently published a paper on their findings.

They have identified five small populations of the birds about 50 individuals in a small forested valley on one fork of the Guatapurí River in Colombia.

The sabrewing population is a case of micro endemism experts say a species restricted to one very small specific place.

It’s considered critically endangered. Finding a species prompts a new list of challenges. What is the best way to protect it whether from storms a changing climate or crowds? Esteban Botero Delgadillo director of conservation science for SELVA a Colombian conservation organization said he and others worried if this news came out there would be a lot of bird watchers and people.

For that reason he added they were very vague about where it was for more than a year. The bird is on Indigenous land which makes management more complicated.

Violence can be a danger in the habitats of some lost birds. The rediscovery in 1999 of a small cluster of yellow eared parrots striking green birds with yellow markings in western Colombia led to the creation of a reserve.

The population grew to thousands. In 2021 the environmentalist who nursed the population to healthy numbers Gonzalo Cardona was shot and killed by an unknown criminal gang his body buried in a shallow grave.

Dr. Botero Delgadillo said his team too must be wary in the field. Another recently found bird on the top 10 list is the black naped pheasant pigeon.

The chicken size bird was found in a remote region of Papua New Guinea in 2022 after not having been documented in 126 years.

Though the existence of a bird may not have been documented by science for a long time that doesn’t mean it is lost to local people.

To find the pheasant pigeon the most endangered terrestrial bird in Papua New Guinea researchers traveled to villages where the bird had last been seen.

Among those was John C. Mittermeier founder of the Search for Lost Birds Project. People who live there are largely subsistence farmers fisherman and hunters and so they know the land and the wildlife really really well Dr.

Mittermeier said. We asked them whether they had seen this species whose local name is auwo. One day one of the birds strutted in front of a camera trap that had been set up.

Seeing those first photos of the pheasant pigeon felt like finding a unicorn Dr. Mittermeier said.

It’s the kind of moment you dream about your entire life as a conservationist and bird watcher. Three species in North America are considered lost.

Best known is the ivory billed woodpecker. Its last universally accepted sighting in the United States was in Louisiana in 1944.It was spotted again in Cuba in 1987. There has not been a confirmed sighting since. Because of grainy videos of what could be the bird the U.S. Fish and Wildlife Service has not declared the bird extinct. The other two birds in North America are the Eskimo curlew and the Bachman’s warbler.