The “inornate” warbler

Early in April last year (2016) I was lucky enough to catch up more than once with a rare Yellow-browed Warbler at my birding “local patch” in north-west London — Brent Reservoir, also known as the Welsh Harp. 

The Yellow-brow can be hard to observe, since it is almost constantly in motion, flitting short distances from branch to branch. Luckily it is not shy, and I had close views of it and also heard its distinctive call, a piercing “tsee-WEET”— strikingly loud for one of the smallest Old World warblers.

The Yellow-browed Warbler (Phylloscopus inornatus) breeds across much of northern Asia and normally winters in tropical south-east Asia. But on leaving the breeding sites some young birds take a wrong turn and head west across Europe instead of south to the usual wintering grounds. In Britain the bird is normally seen only in small numbers in autumn, mainly on the east and south coasts of England or on northern Scottish islands. 

Most of the birds that reach Britain move on, probably to continue west and drown in the Atlantic, but a few — usually only in single figures — attempt to winter here. One of these rare overwintering birds was found at Brent Reservoir on 23 December 2015. It lingered for a few days, allowing some regular local birders and a number of twitchers to see it. (I missed it because I was away over Christmas.) It obligingly stayed until 1 January 2016 so that New Year’s Day birders could include it on their next year list. 

The bird then vanished but, to our surprise, it reappeared (or was it a different bird?) three months later, on 3 April 2016, at another part of the site, where it stayed for a fortnight, showing itself daily. I may be wrong, but so far as I know our spring bird was the first Yellow-brow ever seen in London in April. It was certainly one of only a couple of individuals known to have survived into spring 2016 anywhere in Britain.

According to my bird books, the Yellow-browed Warbler is also known as the Inornate Warbler. Inornate? Have you ever come across this word? I hadn’t, so — as always when confronted by an intriguing word — I turned to the metadictionary website OneLook (www.onelook.com), which searches for words across a range of online dictionaries and encyclopaedias. In this case, OneLook offered just a single reference to “inornate”, in Collins English Dictionary, which gives the definition “simple, or not ornate”.

Now so far as I am concerned, the Yellow-brow does not deserve to be labelled “simple, or not ornate”, since it is a pretty little thing. It has greenish upperparts, whitish underparts and two prominent yellowish-white wing bars. Most strikingly, it has a long yellow supercilium, an eyebrow stripe running from the base of its bill and above its eye and finishing towards the rear of its head. This can be clearly seen in autumn, when the bird is most often encountered in Britain, although by April our bird’s supercilium had become worn and less pronounced.  

The Yellow-brow’s closest relative is the equally rare Hume’s Warbler (P humei), which is similar but generally duller (even more “inornate"?). Better-known near relatives found in Britain are three slightly larger birds — the Common Chiffchaff (P collybita), the Willow Warbler (P trochilus) and the Wood Warbler (P sibilatrix). These three are also eligible to be described as “inornate”, since they have shorter and less obvious eye-stripes and they lack wing bars, although they may have yellower tummies than the Yellow-brow. 

Our Brent Reservoir superstar was last seen on 17 April 2016. I hope it managed to make its way back to its birthplace and find a mate.

An expert birder who has never seen a bird

I learnt recently about a remarkable South American birder who is recognised as one of the continent’s leading bird experts. He can identify hundreds of species, but he has never seen any of them. 

Born in 1986 in Montevideo, Uruguay, Juan Pablo Culasso has been blind since birth. But a gifted sense of hearing has allowed him to memorise more than 3000 different sounds from more than 720 bird species. He is helped by having perfect pitch, which means that he can hear a tone and immediately identify it as F-sharp, B-flat or whatever. Only one in about 10,000 people has this ability. 

Culasso’s interest in birds dates from a young age, when his father read to him from a bird guide that was accompanied by audiocassette recordings of bird calls. The youngster found that he could easily memorise these sounds, and this ability inspired an enduring love of birds. 

In 2003, as a teenager, Culasso was invited to join an ornithologist on a field visit to record  Uruguayan birds such as Tawny-bellied Seedeater (Sporophila hypoxantha) and Rufous-rumped Seedeater (Sporophila hypochroma). This experience led to an obsession with documenting the sounds of nature, and he went on to study bioacoustics in Brazil. 

In 2014 Culasso’s facility for recognising birds through their voices alone won him a prize on a National Geographic television programme. In the final test, he had to identify 15 birds chosen at random from recordings of 250 species, and he recognised every one. He   spent most of his $45,000 winnings on audio equipment.

After a decade in Brazil, Culasso is now back in Montevideo, working — not surprisingly — as a nature sound recordist. His career has even taken him on a two-month trip to Antarctica, where he recorded the wildlife of the Southern Ocean and the sounds of melting icebergs.

Although blindness may seem a major obstacle for birding, Culasso embraces it. He points out that those who rely mainly on sight have a visual field of only 70 degrees ahead of them, while a lack of vision allows one to concentrate on the sounds received from every direction — left and right, front and back, above and below. When he accompanies sighted birders on field trips he regularly identifies birds by sound long before his companions have managed to recognise them by sight. 

Culasso’s success at sightless birding offers a lesson for all birders. It is all too easy to rely mainly on visual identification, but remaining alert to the sounds around you can make a big difference to any birding expedition. 

Rollo’s regrettable legacy

Although it is dispiriting to read about birds that have become extinct in recent times or are heading for oblivion, it is also heartening to learn about species that reappear long after they have been assumed to have died out. 

One example is Beck’s Petrel (Pseudobulweria becki), which was refound a few years ago after being overlooked for 80 years. However, this species still faces a high risk of extinction. Much research is needed if we are to detect, respect and protect its breeding sites, believed to be on small Melanesian islands.

While relishing the re-emergence of this species, I find it irritating that its English name and its scientific binomial both commemorate a man whose activities threatened its survival. Until its rediscovery, Beck’s Petrel was known only from two specimens “collected” during a 1928/29 South Pacific expedition by Rollo Beck (1870–1950), an American ornithologist who seems to have made a living by selling the corpses of vulnerable birds to museums.

Although the petrel that bears his name still survives precariously, Rollo Beck may have contributed to the extinction of at least two other creatures. One of these was the Guadalupe Caracara or Quelili (Caracara lutosa), a bird of prey endemic to Mexico’s Guadalupe Island. Once common on the island, its numbers plummeted towards the end of the 19th century, mainly because of an extermination campaign by goat herders who believed that the bird predated their kids. In 1900, when the caracara had already been almost wiped out, Beck visited the island and found 11 birds. Having no land-based predators (other than goat herders), they were tame and approachable, and Beck shot nine of them to supply to museums as scientific specimens. Since Beck’s fateful trip to the island there have been no confirmed sightings of this species.

In 1906, Beck also “collected” three of the last four known specimens of Pinta Island Tortoise (Geochelone nigra abingdonii) — even though he knew that, like the Guadalupe Caracara, this subspecies of the Galápagos Tortoise had already been almost wiped out. 

After Beck’s testudinal butchery the Pinta Island Tortoise was believed to be lost. But in 1971 a lone male was discovered. Dubbed “Lonesome George”, he was taken to a research station for protection. He died of old age in 2012, after failing to mate successfully with females of a closely related subspecies. 

In view of Rollo Beck’s appalling record, surely it is time to award Beck’s Petrel a less cynical name?