After searching for close to a century for the elusive bird, researchers have finally discovered what is to some considered the birding holy grail. First described from a single female specimen in the 1920s, the moustached kingfisher of the Solomon Islands wasn’t again seen until another two females were collected in the 1950s. But a few weeks ago, ornithologist Chris Filardi, who had himself been searching for the bird for the past two decades, caught and took the first ever photographs of the moustached kingfisher. Many were in awe at this incredible find, until they found out that he killed it.

While on location, Filardi wrote in a blog about the moment he caught the elusive bird, in which his excitement is palpable: “When I came upon the netted bird in the cool shadowy light of the forest I gasped aloud, “Oh my god, the kingfisher.” One of the most poorly known birds in the world was there, in front of me, like a creature of myth come to life.” After almost a century of hiding in the shadowy forest, the beautiful orange and blue plumage of this bird had finally been brought into the light.

These are the 1st-ever photos of a male moustached kingfisher! More on this "ghost" species: http://t.co/1bLrW7HpZZ pic.twitter.com/P879oQ4WaA

— AMNH (@AMNH) September 23, 2015

But what happened next has elicited quite a bit of controversy. Filardi then “collected” (read: killed) the bird. This has been the practice of biologists the world over for hundreds and hundreds of years, particularly during the Victorian era when tens of millions of rare and exotic animals were killed and stuffed for museums. These specimens have undoubtedly been invaluable for scientific research, and yet in more recent times – especially with the advent of photography and DNA analysis – this custom of killing the animal in question has fallen out of practice.

“This was neither an easy decision nor one made in the spur of the moment,” wrote Filardi in a riposte to the mounting criticism. “This was not a 'trophy hunt.'” He argues that there are certain data that are simply unobtainable from just blood and DNA samples alone, including “a comprehensive set of material for molecular, morphological, toxicological, and plumage studies.” The real question really comes down to whether such a rare and elusive species, which managed to evade capture for at least half a century and which the IUCN consider endangered (though this could be due to lack of data), can take the killing of the individual male.

Filardi goes on to cover this point, claiming that “though sightings and information about the bird are rare in the ornithological community, the bird itself is not.” From the surveys conducted in the forest during the expedition in which the bird was discovered, Filardi estimates that there are as many as 4,000 of them surviving in the rainforest. “On this trip, the real discovery was not finding an individual Moustached Kingfisher, but discovering that the world this species inhabits is still thriving in a rich and timeless way.”

However, this hasn’t stopped one particularly vocal critic. Marc Bekoff, professor of ecology and evolutionary biology at Colorado University, wrote in the Huffington Post that collecting specimens is “still the name of the game for some researchers: find a beautiful, unique, or rare animal and then kill it in the name of something or another to justify the unnecessary slaying.” Whether an essential part to biological research, or a throwback to an outdated practice, it seems those working in these circles are going to need to have a serious debate about which direction they take.