From the Siau scops-owl to the Cuban kite: A global hunt aims to find 10 birds long feared extinct

The top 10 "most wanted" bird species.

(CNN)If you've never heard of the Siau scops-owl, there's a good reason why -- and it's not because your knowledge of birds isn't quite up to scratch. Nobody has seen the elusive owl since 1866, and it's not the only such missing species.

Researchers, conservationists and birdwatchers all over the world are being called upon for a new effort to find the top 10 "most wanted" bird species, which haven't been spotted in over a decade but still haven't been classed as extinct.
A joint effort by conservationist group Re:wild, the American Bird Conservancy and BirdLife International, with data support from the Cornell Lab of Ornithology and its birdwatching platform eBird, the "Search for Lost Birds" hopes to locate these apparently vanished creatures.
    The birds in question were last seen and documented at a number of different times, ranging from the Siau scops-owl last glimpsed in 1866 in Indonesia, to the Cuban kite last observed in 2010 in Cuba.
      They also span five continents, with four hailing from Asia, two from Africa, two from South America, one from North America and one from Oceania. India is the only country with more than one bird on the list, with the Himalayan quail, last sighted in 1877, and the Jerdon's courser, which was witnessed much more recently in 2009.
        "We really want to find these species, which are completely overlooked and ignored, and turn them into species that are a focus for conservation efforts," Barney Long, Re:wild's senior director for conservation strategies, told CNN.
        The Siau scops-owl was last spotted in 1866 in Indonesia.
        "Obviously, for these 10, we really hope they'll all be found," he added. "That might not be the case -- we might be too late for some of them, but we really hope we'll find them all."
          The search will begin with two expeditions in the next year focusing on the Siau scops-owl, which has only ever been documented once, and the Madagascan dusky tetraka, which was last documented in 1999. The organizations' efforts will also be aided by the eBird platform, which has over 700,000 registered users who can submit sightings.
            Although all of the species are classified as critically endangered by the International Union for Conservation of Nature (ICUN), the team is optimistic, especially as the Indonesian black-browed babbler, which had not been documented since 1848, was found again in February this year.
            The "Search for Lost Birds" is an extension of re:wild's "Search for Lost Species" program, which has rediscovered eight of its 25 most wanted species since its launch in 2017.