Lost and found: Asia
Across the planet, species shrouded in mystery may never have existed, could be rediscovered or already have been. In the first in a new series, Alex Berryman looks at some of these enigmatic birds.
Across the planet, species shrouded in mystery may be known from just one specimen or sighting. Some may never have existed; others have been rediscovered and some could still survive unseen. In the first in a new series, starting in Asia, Alex Berryman takes a look at some of these enigmatic birds.
Few achievements are more celebrated in ornithology than discovering a species new to science, or rediscovering one thought extinct or ‘lost’ for decades. Despite this, few birders seem keen to take up the gauntlet, preferring instead to visit well-established sites to see a predictable suite of species. In this first part of a new series looking at ‘lost’ and recently ‘found’ species, I turn to Asia.
Lost or not?
In some cases, species may drop off the ornithological radar because of their inaccessibility. Damar Flycatcher, a little-known Ficedula flycatcher endemic to the small and remote island of Damar, Indonesia, was last seen by ornithologists in 1898 before its ‘rediscovery’ more than 100 years later. In reality, no further ornithological investigation of the island had been made until the species was seen again, in 2001, when it was found to be locally common.
Occasionally, the quest for a species might be halted if new evidence arises that casts doubt on its validity. Specimens of ‘Cream-bellied Munia’, collected on Borneo and later acquired in a bird market in Jakarta, Java, were originally described as a distinct species in 1996. Just two years later, van Balen (1998) convincingly argued that the variation in the specimens, and the fact that no wild observations had ever been made, led to the more probable conclusion that the specimens are hybrids, most likely of Scaly-breasted and White-bellied Munia parentage.
More recently, the enigmatic Vaurie’s Nightjar, known from a single specimen procured in 1929 on the southern edge of the Taklamakan Desert, Xinjiang, in the extreme north-west China, suffered a similar fate when molecular data (Schweizer et al 2020) indicated that the specimen is probably a fledgling Eurasian Nightjar, its age explaining the otherwise puzzlingly small size.
In other instances, the rediscovery of a ‘lost’ species in the region has been the result of extraordinary effort and initiative – and a bit of luck.
While birding in Shetland in October 2020, I was sent a photograph I never thought I would see: almost 12,000 km away, Black-browed Babbler – Asia’s longest-‘missing’ bird – had been rediscovered (Akbar et al 2020). The mystery that surrounded this species was twofold. First, known from a single specimen procured somewhere in southeast Borneo from 1843-48, nothing of its location, habitat or elevation was known. Second, after so long without a sighting, was it extinct?
Many assumed the answer to the latter question was ‘yes’; an understandable conclusion given the near-complete destruction of forests where Schwaner (the original collector) is known to have prospected. However, few had adequately searched, and it was with great excitement that news of this species’ rediscovery was met. Details (including the locality, habitat and so on) are currently being formalised for publication later this year, thus are not for disclosure here, but that this species was re-found after a 170-year absence surely gives hope that other ‘lost’ species are awaiting rediscovery.
The drab appearance of Sillem’s Mountain Finch – a high-elevation finch which is, in fact, a dull rosefinch
– is far exceeded by the extraordinary tale of its (re)discovery. In 1929, while exploring high altitudes in west Tibet, J A Sillem collected specimens attributed to Brandt’s Mountain Finch, although in his diary, Sillem himself acknowledged that one of the specimens belonged
to “another species”. It was not until 1991 that C S Roselaar was rummaging through the Zoological Museum of Amsterdam’s collection of snowfinches when he chanced on the specimens and noticed that two of Sillem’s differed from known species in several salient plumage characters – he went on to describe them as a separate species.
Fast forward to 2012: Yann Muzika, while on an arduous trek in Yeniugou Valley in west Qinghai, China, took photographs of an unidentified finch which he uploaded to Oriental Bird Images. The website’s editor, Krys Kazmierczak, quickly sounded the alarm that the images – among them photographs of the hitherto unknown female – looked like the long-lost finch. Some 83 years after Sillem’s expedition, and more than 1,500 km away from its location, Sillem’s Mountain Finch was found!
Despite the investment of much effort, a number of species in Asia continue to evade the birders and ornithologists seeking them. Among the high-profile ‘missing’ species are Crested Shelduck (last seen 1964), Pink-headed Duck (1935), Himalayan Quail (1876),
Siau Scops Owl (1866), Rück’s Blue Flycatcher (1918) and Sulu Bleedingheart (1891).
Perhaps Asia’s most famous ‘missing’ species, though, is White-eyed River Martin. In January 1968, while conducting a ringing expedition at Bueng Boraphet, a reservoir and marsh in central Thailand, a team of scientists encountered something remarkable: a hirundine with a bold white eyering and two wire-like plumes.
It was described as a new species, White-eyed River Martin, and over the next three years 12 specimens were collected, with rumours of more than 100 being caught and sold elsewhere. A single field observation, at the same locality, in 1978, followed by two unconfirmed reports – the most recent of which was in 1986 – are the last signs of this bird, which remains one of Asia’s greatest avian enigmas.
The extraordinarily late discovery of this species, in a country as well explored as Thailand, is equalled in mystery only by its near-immediate disappearance. Almost nothing is known. All specimens were taken in Bueng Boraphet from December to February, so was it a resident or a migrant. Where did it breed? What did it feed on?
Although its resemblance to African River Martin led many to assume that its ecology must ostensibly be similar, Tobias (2000) pointed out that Whiteeyed River Martin was never tangibly associated with rivers – in fact, as specimens were brought to the scientists by local villagers, the exact habitat from which the birds were collected is entirely unknown. He also raised the interesting possibility that White-eyed River Martin might be nocturnal or crepuscular, principally on account of its proportionally massive eyes.
In any case, habitat degradation throughout all likely breeding and wintering grounds, exacerbated by trapping at roost sites and the absence of recent observations, make rediscovery of this species doubtful. However, this should not dissuade the ambitious: such a rediscovery would reward the finder with rightful admiration, and one of Asia’s greatest ornithological mysteries would be solved!
Unseen for more than 80 years, the chance of Javan Lapwing being
rediscovered seems equally bleak. Known with certainty from only Java, it inhabited agricultural land, wet cattle pasture and abandoned paddyfields. Extensive surveys and interviews with local people in the early 2000s, covering dozens of localities, failed to rediscover it. The species is now surely extinct on an island that has seen extraordinary human population growth: from 5 million people in 1815 to more than
150 million presently.
Historically, it was reportedly impossible to overlook and there are reports of it being easy to find as late as the 1950s and 1960s. Although agricultural intensification is often cited as a reason for its demise, Iqbal et al (2013) concluded that “the combination of the species’ handsome, distinctive appearance, its habit of persistently circling human intruders on its territory, together with the long tradition of waterbird hunting in Java are major factors in the demise of the Javanese Lapwing, rather than loss of habitat”. In May 1953, two doves were shot on Mount Kanlaon on the Philippine island of Negros. One failed to reach the ground, but the other, a female, was collected and described as a new species: Negros Fruit Dove. The bird was vivid dark green with a broad yellow eyering and a bright yellow wing-bar and undertail coverts. It has not been seen since.
The deforestation of the Philippines has left it with one of the most imperilled avifaunas in the world. Nowhere is this truer than on Negros, where as long ago as August 1877, anticipating extensive remnant forest in southernmost Negros, A H Everett encountered instead “one vast field of maize, sugar-cane, and hemp, perfectly cleared, even far up the steep-sides of the mountains”. Today, 3-4% of forest cover remains, none of it below 800 m. Although it may seem unlikely, there is indication that this colourful columbid is not extinct and may, one day, reward the persistent with its rediscovery. The specimen was collected at 1,100 m, above the elevation of some remaining dipterocarp forest. A small green dove with a yellow eyering was reportedly shot by a local hunter on Mount Kanlaon in “about February 2008”, while other large pigeons have survived in likely areas despite intense hunting pressure (Collar and Lambert 2013). A search of neighbouring Panay, with which Negros shares near-total avian affinity, perhaps offers the best chance.
The ‘golden era’ of species discovery may be long gone, but recent decades have continued to reward ambitious birders with novel species. Since 2000, 32 new bird species have been described from Asia – the majority of them from the Indonesian Archipelago (44%)
and the Philippines (16%). Just last year, Frank Rheindt and his colleagues described a phenomenal 10 taxa new to science (five species and five subspecies) from Indonesia (Rheindt et al 2020). While the chances of new discoveries diminish with every one that is made, new birds continue to be found. In
2016, Eaton et al (2016) discovered a white-eye and blue-flycatcher in southeast Borneo, both of which are awaiting formal description.
The following year, Eaton struck again. Exploring the island of Selayar, off south-west Sulawesi – at the time unvisited by ornithologists for decades – he found a single leaf warbler in an area of remnant secondary forest, which he observed for only a few minutes before having to depart. In January 2020, my own visit to the island resulted in the first sound recordings of the bird and affirmed it as an undescribed species (Berryman and Eaton 2020), although it too awaits a formal description.
Finding ‘lost’ species matters. When Cebu Flowerpecker was rediscovered in 1992, after 86 years without a sighting, it called attention to a troubling phenomenon whereby species are prematurely labelled extinct and then nothing is done to conserve their habitats, such that they may then genuinely become extinct, known as the ‘Romeo Error’.
Forty years prior to its rediscovery, Cebu Flowerpecker had been presumed extinct on the incorrect assumption that all forest on its Philippine island home had been cleared. Consequently, the island was ‘written off the biological map’ by 1960, until the efforts of visiting birders in the 1990s found it in a narrow strip of habitat (Collar 1998). In the intervening decades, remaining forests had been felled, and by the time of the flowerpecker’s rediscovery, almost all of Cebu’s forest had been cleared and the time required to implement robust conservation action had been irretrievably lost. Although the flowerpecker clung on at the site of its rediscovery, it has not been seen unequivocally for more than a decade. If it does persist, it can only do so in tiny numbers and other taxa have undoubtedly been lost due to our failure to protect Cebu’s forests.
Birders should not underestimate their ability to contribute to the discovery of new species and the rediscovery of lost ones. Binoculars, a camera, and – perhaps most crucially – a willingness to abandon the beaten track to explore more remote regions are all that are needed. While some species are almost certainly gone forever, others are plausibly extant – if Black-browed Babbler can be found after 170 years of absence, anything is possible! The tale of Cebu Flowerpecker should be a warning to us all. ■