Separating Pale-legged & Sakhalin Leaf Warbler on Call

Editor’s note: In the photo above, a Pale-legged Leaf Warbler emits its characteristic “tink” call in Microforest 4, Cape Nanhui, Pudong, 27 Aug. 2017. The tink call of Pale-legged is appreciably higher-pitched than that of Sakhalin Leaf Warbler. Distinguishing the two calls is the subject of this post. — Craig Brelsford

Last September, in “Pale-legged Leaf Warbler & the Shanghai Big 5,” I asserted that “Pale-legged Leaf Warbler is safely separable from Sakhalin Leaf Warbler only by song.” I was wrong. Call as well as song is a reliable separator. In this post, I am going to tell you how I arrived at this insight, and I will show you how you too can achieve clear, indisputable ticks of these tricky species through call alone.

Experts since at least as far back as 1989 have been arguing that Pale-legged Leaf Warbler Phylloscopus tenellipes and Sakhalin Leaf Warbler P. borealoides are separable not only by their distinctive songs but also by their calls. Thailand-based birder and shanghaibirding.com contributor Phil Round is among those making that argument. Round and his co-authors write: “[T]he call of P. tenellipes is markedly higher in frequency than that of P. borealoides” (Round et al., “Addition of Kamchatka Leaf Warbler Phylloscopus examinandus and Sakhalin Leaf Warbler P. borealoides to Thailand’s Avifauna,” downloadable through shanghaibirding.com).

If your ear is good, or even if your ear is just average and you have a sound-recorder, then you too can appreciate the higher frequency of the call of Pale-legged. A sound-recorder is very important, because if you upload your recordings to databases such as eBird and the Macaulay Library, then you will be able to “see” the sound in the audio spectrogram.

Our first exhibit is the spectrogram of a call I sound-recorded of Sakhalin Leaf Warbler on 8 May 2016 in Cape Nanhui’s Microforest 4 (30.953225, 121.959083). The frequency is 4.8 kilohertz, a number that matches closely the frequency of Sakhalin calls on xeno-canto.org.

Audio spectrogram of call of Sakhalin Leaf Warbler.

Here is the sound-recording:

Sakhalin Leaf Warbler, call, Microforest 4 (30.953225, 121.959083), 8 May 2016 (00:15; 1 MB)

Now consider the spectrograms and sound-recordings of Pale-legged Leaf Warbler below. The spectrogram immediately below was recorded by me on 10 June 2016 in my wife Elaine Du’s hometown of Boli, Heilongjiang, part of the breeding range of Pale-legged Leaf Warbler. The call (here a grace note) and song both clock in at about 6 kHz, a frequency a full 25 percent higher than the call of Sakhalin Leaf Warbler and, as with Sakhalin, consistent with the frequencies of Pale-legged calls on xeno-canto.org.

Audio spectrogram of call plus song of Pale-legged Leaf Warbler.

Here is the sound-recording:

Pale-legged Leaf Warbler, call and song, Xidaquan National Forest (45.727751, 130.317316), Boli, Heilongjiang, 10 June 2016 (01:59; 6 MB)

The spectrogram below is of a brief sound-recording I made in Microforest 4 this past Sunday. The song element of this passage migrant is absent (though note that I have heard Pale-legged and Sakhalin singing in Shanghai in spring). The call has a frequency of 5.9 kHz and clearly belongs to Pale-legged Leaf Warbler.

Audio spectrogram of call of Pale-legged Leaf Warbler.

The sound-recording:

Pale-legged Leaf Warbler, call, Microforest 4 (30.953225, 121.959083), 27 Aug. 2017 (00:01; 193 KB)

Why should you care about all this? Because prepared birders have a chance to get solid ticks of “Pale-Saks” that are merely calling and not necessarily singing. If you hear a Pale-Sak calling and trust your ear (or better yet, sound-record the call and later analyze the spectrogram), then you may be able to go beyond the safe, boring record of “Pale-legged/Sakhalin Leaf Warbler” to a more satisfying full tick.

Pale-legged Leaf Warbler Phylloscopus tenellipes pumping its tail vigorously while remaining otherwise motionless and while standing (as is its wont) on a thick branch (top panels); and a second individual making its high-pitched "tink" call (bottom panels). Microforest 4 (30.953225, 121.959083, top panels) and Microforest 1 (30.923889, 121.971635, bottom panels), Cape Nanhui, Pudong, Shanghai, China, 27 Aug. 2017.
Pale-legged Leaf Warbler Phylloscopus tenellipes performing typical behaviors. Top panels: pumping tail vigorously while remaining otherwise motionless on a sturdy branch. Bottom panels: making the high-pitched ‘tink’ call, again on a thick branch. Microforest 4 (30.953225, 121.959083, top panels) and Microforest 1 (30.923889, 121.971635, bottom panels), Cape Nanhui, 27 Aug. 2017. (Craig Brelsford)

Accurate, plentiful records from Shanghai will help researchers such as Round get a clearer picture of the movements and population of these understudied species. As Round et al. write: “Increased sampling of migrants may also resolve the differences in timing of passage between P. examinandus and P. borealis on the one hand, and P. borealoides and P. tenellipes on the other” (“Addition”; hyperlink mine).

My trusty Olympus DM-650 sound recorder. In May, the height of migration season, my sound recorder is like the American Express card: 'Don't Leave Home Without It!'
My Olympus DM-650

What’s more, you do not need to spend much or even know much to record good audio. My Olympus DM-650 costs less than US$250. I have no microphone other than the one built into my pocket recorder, and I possess no parabola. I record in lossless 48kHz .wav. The very scientific-looking spectrograms displayed in this post are generated automatically by eBird and Macaulay.

In Shanghai and throughout China, important facts about common birds such as Pale-legged Leaf Warbler and Sakhalin Leaf Warbler remain unknown. This ornithological semi-wilderness is both difficult and exciting. If we rise to the challenge and become better birders, then we will make new discoveries and blaze a trail of knowledge for future birders to follow.

Asian Dowitcher in Shanghai

On Sat. 5 Aug. 2017, I resumed birding at Pudong’s Cape Nanhui after a two-month hiatus. Battling apparent temperatures of 42 degrees Celsius (108 degrees Fahrenheit), partner Ian Reid (above) and I noted 74 species. The haul was good, but even better was the insight it afforded me. Once again, I learned that when it comes to birding, the most southeasterly point of Earth’s Greatest City delivers month after month, season after season.

Ian and I had 3 juvenile Asian Dowitcher, the most notable among an all-star team of shorebirds that included 8 Black-tailed Godwit, Ruff, 12 Broad-billed Sandpiper, and 3 Curlew Sandpiper still mainly in brick-red breeding plumage. A Red-necked Phalarope was making use of fallow rice paddies, and 6 Grey-tailed Tattler were on the mudflats near Donghai Bridge. We had unusual Nanhui records of Pied Kingfisher and Ruddy Shelduck.

The microforests were quiet, but a very early record of Eastern Crowned Warbler and Yellow-rumped Flycatcher offered a preview of the passerine party coming in September. We had four species of bittern: Eurasian Bittern, Yellow Bittern, Cinnamon Bittern, and Black Bittern.

In my nearly 10 years in Shanghai, I had never birded Cape Nanhui in the first week of August. During Shanghai’s hottest month of the year, I am almost always birding in cooler climes—in Qinghai last year, for example, and in 2015 in my wife Elaine’s hometown in Heilongjiang.

Ian’s and my day both reminded me of the good reasons for vacating Shanghai this time of year and showed me the treasures I have been missing. Through the oppressive heat, which ensured that you would never stop sweating, and the 81-percent humidity, which ensured that the perspiration wouldn’t do much good, the Australian birder and I steadily built up an impressive list.

For all 74 species, see our eBird list. Below, our highlights.

Asian Dowitcher Limnodromus semipalmatus

Asian Dowitcher through the spotting scope and recorded by my iPhone 6. 5 Aug. 2017. (Craig Brelsford)
Asian Dowitcher at South Pond, 5 Aug. 2017. Photo taken with iPhone 6 and PhoneSkope adapter attached to my Swarovski ATX-95 spotting scope. (Craig Brelsford)

Our trio were juveniles, with their dark-brown crowns and buff-fringed, dark-brown upperparts. They were feeding together at South Pond (30.873934, 121.953180). The tide had hit the nearby sea wall and driven in small numbers of shorebirds of various species, among them Sharp-tailed Sandpiper Calidris acuminata, Curlew Sandpiper C. ferruginea, Long-toed Stint C. subminuta, and Broad-billed Sandpiper C. falcinellus.

An East Asian specialty, Asian Dowitcher breeds in a disjointed set of ranges from western Siberia to Heilongjiang. The IUCN lists it as Near Threatened.

Eastern Crowned Warbler Phylloscopus coronatus

We found a single individual in the Cathedral of Birding, the broad, spacious northern end of Microforest 4 (30.953225, 121.959083). This is a very early record of a species that, like so many other passerines on passage through the Shanghai region, does not begin to show up in impressive numbers until September. As with the dowitchers, when I saw this warbler, my initial reaction was, “What else have you been missing over the years for failing to bird Nanhui in early August?”

Nearby we had female Yellow-rumped Flycatcher Ficedula zanthopygia, a less surprising record, as the species breeds in Jiangsu.

Ruddy Shelduck Tadorna ferruginea

Ruddy Shelduck, Cape Nanhui, 5 Aug. 2017. (Craig Brelsford)
Ruddy Shelduck, Cape Nanhui, 5 Aug. 2017. (Craig Brelsford)

Ruddy Shelduck in August is yet another unexpected record. We found a single individual associating with domestic waterfowl near the entrance to the defunct wetland reserve (30.920507, 121.973159). The species is uncommon in Shanghai at any time of year, with most records coming in winter.

Pied Kingfisher Ceryle rudis

Perhaps the most surprising aspect of this record is that it is surprising at all. Pied Kingfisher breeds throughout southern China, yet this record was my first of the species in Shanghai. A pair has been present at Cape Nanhui since at least July.

Eurasian Bittern Botaurus stellaris

Eurasian Bittern, Cape Nanhui, 5 Aug. 2017. (Craig Brelsford)
The boom of Eurasian Bittern is heard in Shanghai in spring. An August record is surprising. (Craig Brelsford)

Our first of the four species of bittern. We found 2.

Yellow Bittern Ixobrychus sinensis

Yellow Bittern, Cape Nanhui, 5 Aug. 2017. (Craig Brelsford)
Yellow Bittern breeds in our area. (Craig Brelsford)

We found 24 of this local breeder along the length of the 30-km coastal road.

Cinnamon Bittern Ixobrychus cinnamomeus

Cinammon Bittern, Cape Nanhui, 5 Aug. 2017. (Craig Brelsford)
Cinnamon Bittern is another species that in Shanghai probably has been under-recorded over the years. (Craig Brelsford)

Found in habitats similar to Yellow Bittern, but in much smaller numbers (4).

Black Bittern Ixobrychus flavicollis

Black Bittern, Cape Nanhui, 5 Aug. 2017. (Craig Brelsford)
Black Bittern, Cape Nanhui, 5 Aug. 2017. (Craig Brelsford)

One was seen flying just north of Eiffel Tower (30.850531, 121.878047). This species has an affinity for swamps in forests and is uncommon in Shanghai. Saturday’s record was only my second in the city.

Common Kestrel Falco tinnunculus

Common Kestrel Falco tinnunculus being mobbed by Black-winged Stilt Himantopus himantopus. © Craig Brelsford (craigbrelsford.com, shanghaibirding.com). 5 Aug. 2017. Cape Nanhui, Pudong, Shanghai, China.
Juvenile Common Kestrel blundered into a confrontation with Black-winged Stilt. The youngster soon realized its error and went looking for littler prey. (Craig Brelsford)

A species common in Shanghai, noted here only because of the circumstances under which Ian and I found it. The first impression of “juvenile falcon” that I received came not from the plumage but from the blunders of the kestrel. The falcon got too close to some juvenile Black-winged Stilt–and found itself being chased off by an adult, a giant in comparison. This was clearly a rookie’s error and betrayed the inexperience of the attacker.

In the photo above, note the lightly streaked ear coverts, the lack of scythe-like wings (as in Eurasian Hobby), black remiges, and long tail with rounded tip. The strong black streaking on the underparts will grow thinner as the kestrel matures.

Peregrine Falcon Falco peregrinus

A welcome addition to any Nanhui list, Falco peregrinus is usually recorded in Shanghai in autumn and winter. Sharp-eyed Ian spotted the falcon roosting in an area that used to contain reed beds but has since been flattened by the backhoes into a savanna-like landscape. I got video on my iPhone through the spotting scope.

Featured image: Australian birder Ian Reid scans the mudflats at Cape Nanhui, Pudong, 5 Aug. 2017. In the background is Donghai Bridge. (Craig Brelsford)

Kamchatka Leaf Warbler in Shanghai

Seen at Pudong’s Cape Nanhui on Sun. 4 June 2017: Kamchatka Leaf Warbler Phylloscopus examinandus. Veteran British birder Michael Grunwell and I found our 4 Kamchatkas in Microforest 4 (30.953225, 121.959083), the largest of the tree plantations on the landward side of the sea wall. The species is an all-time first for the Shanghai eBird list.

Just after sunrise, Michael and I, as is our wont, were doing “drive-by birding”creeping along the edge of the road, listening out for birds. Suddenly, I heard an unfamiliar sound.

My gut said, “Hard, loudTaiga Flycatcher?”

Taiga was not even close, of course. Note, however, what my gut was not saying: “Arctic Warbler,” a bird whose call I know well. This call was decidedly not an Arctic’s, though it soon dawned on us that we were hearing some type of leaf warbler.

To see why my gut did not say Arctic, compare my recordings of the tight “tzit” call of Arctic Warbler with the looser call of Kamchatka Leaf Warbler:

Arctic Warbler Phylloscopus borealis, Yangkou-Rudong, Jiangsu (32.560095, 121.041956), 16 May 2015 (00:09; 1.9 MB)

Kamchatka Leaf Warbler P. examinandus, Microforest 4 (30.953225, 121.959083), Cape Nanhui, 4 June 2017 (00:25; 4.9 MB)

Michael and I skidded to a stop and poked our heads into the green tangle of locust trees. The call was being followed by a song. Only upon hearing the song did I think of Arctic Warbler. But here too, the song, though similar, was distinctive—wavier than the straight trill of Arctic. Look at the spectrograms below.

Spectrogram of Craig Brelsford's recording of Kamchatka Leaf Warbler Phylloscopus examinandus.

The spectrogram above is of my recording 4 June 2017 of Kamchatka Leaf Warbler. Note the pattern: downward sweeps followed by an upward sweep. No one would liken that song to an insect’s. Below, the spectrogram of my 2015 recording of the song of Arctic Warbler. Note the straight, cricket-like trill.

Spectrogram of Craig Brelsford's recording of Arctic Warbler Phylloscopus borealis.

Here are the recordings whose spectrograms are shown above:

Arctic Warbler, Yikesama National Forest, Hulunbeier, Inner Mongolia (52.150833, 121.465639), 16 July 2015 (01:00; 3.2 MB)

Kamchatka Leaf Warbler, Microforest 4, 4 June 2017 (00:48; 9.3 MB)

After hearing several song-call cycles, Michael, my more experienced partner and the man who has taught me more than anyone about birding, first said the words “Kamchatka Leaf Warbler.”

Michael has birded the Indonesian islands of Flores and Komodo, where Kamchatka Leaf Warbler winters. Michael said that, last winter, walking through the forests there, he heard dozens of times the call of P. examinandus.

“I know that call,” Michael said.

I whipped out my Olympus DM-650 voice recorder and recorded the calling and singing warbler. Meanwhile, we caught our first glimpse of the individual. It was clearly an “Arctic-type” leaf warbler.

What is an “Arctic-type” leaf warbler? An Arctic-type leaf warbler is a member of one of four closely related taxa divided among three species: Japanese Leaf Warbler Phylloscopus xanthodryas, Kamchatka Leaf Warbler P. examinandus, and Arctic Warbler P. borealis borealis and P. b. kennicotti.

Per's map of Arctic-type warblers.
Leaf-warbler expert and Shanghai Birding member Per Alström is the person most responsible for our current understanding of Arctic-type leaf warblers. Alström’s PDF, from which this page is taken, is a handy introduction to leaf warblers in China and is downloadable through shanghaibirding.com.

Arctic Warbler is by far the most widespread breeder in the complex. P. b. borealis breeds across northern Eurasia, from Scandinavia to northeast China and the Russian Far East. P. b. kennicotti breeds in western Alaska.

As their names suggest, Japanese Leaf Warbler breeds mainly in Japan (Honshu, Shikoku, Kyushu), Kamchatka Leaf Warbler mainly in the southern Kamchatka Peninsula (as well as on Hokkaido and Sakhalin and in the Kuril Islands).

In 2010 Shanghai Birding member Per Alström et al. proposed the current way of viewing the Arctic-type warblers. Previously, the taxon examinandus was putative, not even reaching the subspecies level; Alström and his team showed that examinandus, with its distinctive song and call, merits recognition not as a subspecies of Arctic Warbler but as a species in its own right.

Of the three Arctic-type species, Japanese Leaf Warbler most stands out, being on average yellower than the two others. Arctic and Kamchatka look much more alike.

There are, however, some slight differences. Kamchatka is said to have a “marginally longer bill, tarsi and tail” than Arctic (del Hoyo & Collar). Sure enough, the Kamchatka I photographed is long-billed. Take a look below.

Arctic Warbler (top) and Kamchatka Leaf Warbler. Both by Craig Brelsford.
Arctic Warbler (top) and Kamchatka Leaf Warbler. Both birds show the classic features of Arctic-type warblers, among them a long supercilium that does not reach bill base, a dark smudge on the lower mandible, and mottled ear coverts. Kamchatka is said to be slightly greener on average than Arctic, a description that these photos do not contradict. The bill of Kamchatka is also marginally longer than Arctic’s, and in these profile shots one notes the longer bill of the Kamchatka and the stouter bill of the Arctic. I would not suggest basing an Arctic-Kamchatka ID on plumage and bare parts. Plumage and bare parts can, however, enhance the quality of a song- or call-based ID. Top: South Lock (30.860073, 121.909997), Cape Nanhui, 13 May 2017. Bottom: Microforest 4 (30.953225, 121.959083), 4 June 2017. (Craig Brelsford)

Michael and I heard our loudest song and calls during that first, early morning encounter. However, we heard Kamchatka calling throughout the day.

Our new Shanghai record, combined with late-May and early-June records from nearby Zhejiang, suggests that in this region, once the wave of Arctics passes through around 15 May, Kamchatka Leaf Warbler may be the Arctic-type to look out for.

BIBLIOGRAPHY

Alström P., T. Saitoh, D. Williams, I. Nishiumi, Y. Shigeta, K. Ueda, M. Irestedt, M. Björklund & U. Olsson (2011). The Arctic Warbler Phylloscopus borealis—three anciently separated cryptic species revealed. Ibis 153:395-410. Available at https://www.shanghaibirding.com/wp-content/uploads/2019/04/Alstrom-et-al-2011-Arctic-Warblers-IBIS.pdf (accessed May 10, 2019).

Brelsford, C. (2017). eBird Checklist: https://ebird.org/ebird/view/checklist/S37369822. eBird: An online database of bird distribution and abundance [web application]. eBird, Ithaca, New York, USA. (Accessed: May 10, 2019)

Join Shanghai Birding for the very latest bird sightings in Shanghai.
Join Shanghai Birding for the very latest bird sightings in Shanghai.

Brelsford, Craig, moderator. Shanghai Birding, a WeChat group. Discussions with various birders, chief among them Hangzhou birder Cheng Qian, who had information about sightings of P. examinandus in Zhejiang. Beijing-based Swedish birder Jan-Erik Nilsén also provided timely advice. To join Shanghai Birding, in WeChat, friend Craig Brelsford (WeChat ID: craigbrelsford). In your friend request, please make it clear that you wish to join Shanghai Birding.

del Hoyo, J. & Collar, N. (2017). Kamchatka Leaf-warbler (Phylloscopus examinandus). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona, Spain (retrieved from https://www.hbw.com/node/1343935 on May 10, 2019).

Jackett, N. (25 Feb. 2016). First Kamchatka Leaf Warbler recorded for Australian Mainland. eBird Australia: https://ebird.org/content/australia/news/first-recorded-kamchatka-leaf-warbler-for-australian-mainland/. eBird, Ithaca, New York, USA. ebird.org (accessed: May 10, 2019).

Featured image: Kamchatka Leaf Warbler Phylloscopus examinandus. On 4 June 2017 at Cape Nanhui, birders Michael Grunwell and Craig Brelsford found the individual pictured here and three others. (Craig Brelsford)

‘One of My All-time Ornithological Highlights’

“I have thought a lot about yesterday and can honestly say, it must be one of my all-time ornithological highlights.”

— Dr. Mike May, message to Craig Brelsford, 14 May 2017

Those are the words not of a new birder, but of a highly experienced visiting birder with thousands of birds on his life list who resides in bird-rich Extremadura, Spain.

Birding Pudong’s Cape Nanhui at the height of the spring migration left Mike May open-mouthed. Should anyone be surprised? The most southeasterly point of Shanghai is a world-class birding site.

Orange-headed Thrush Geokichla citrina, Cape Nanhui, 13 May 2017. (Craig Brelsford)
Orange-headed Thrush Geokichla citrina made a thrilling appearance 13 May 2017 at the Photographers’ Corner at Cape Nanhui’s Magic Parking Lot (30.884898, 121.968229). (Craig Brelsford)

Mike’s 92-species day, Sat. 13 May 2017, with Beijing-based Swedish birder Jan-Erik Nilsén and me included ultra-rarities such as Orange-headed Thrush as well as Pallas’s Grasshopper Warbler and Lanceolated Warbler. A pair of sub-adult Black-faced Spoonbill were getting by on the ever-shrinking pools at the beleaguered site.

The eBird list for Pudong Nanhui Dongtan Wetland.
The eBird list for Pudong Nanhui Dongtan Wetland. Submit your records! It’s fun!

These records brought the all-time list for Cape Nanhui to 288 species, according to eBird—making Cape Nanhui the second-hottest birding hot spot in China.

Let me say that again: Of the thousands of birding spots in this vast, mega-diverse nation, the cape 60 km southeast of People’s Square is second only to Baihualing in Yunnan in species noted.

Sound unbelievable? Let me say something even more unbelievable: Not only is this rich spot completely unprotected, with not even a square meter preserved in any legal way; but it is, to the contrary, being actively destroyed, even as I tap out these words.

The backdrop to the work of Mike, Jan-Erik, and me was fleets of bulldozers and backhoes, busy throughout the weekend. They clattered and clanged, and the pumps transferring water into the newly dug canals whirred and chugged.

Mike May (R) and Zhāng Dōngshēng (张东升) meet. Dōngshēng, a professor at Shanghai Ocean University, is leading an effort to conserve Cape Nanhui.
Mike May (R) and Zhāng Dōngshēng (张东升) meet. Dōngshēng, a professor at Shanghai Ocean University, is leading an effort to conserve Cape Nanhui. (Craig Brelsford)

The pace of transformation is faster than ever now.

“Nanhui is gone,” my partners and I said.

A major ecological area, a place combining ease of access to millions of residents of Earth’s largest city and a favorable position on Earth’s greatest migratory flyway, is being utterly transformed.

While the Cape Nanhui that I have long known falls, huge tracts of adjacent tidal mudflat are being reclaimed, adding dozens of square kilometers to the land area of Cape Nanhui. Birding there in theory could have a future. A Cape Nanhui Nature Reserve could be set up in the new area.

Where Black-faced Spoonbill once foraged, digging machines now crawl, transforming critical reed-bed and marshland habitat into an artificial forest. Looming in the background is the brand-new satellite city, Lingang. Nanhui, Shanghai, 26 March 2015.
Where Black-faced Spoonbill once foraged, digging machines now crawl. Where once one savored the sound of Marsh Grassbird and Reed Parrotbill, now one cringes at the clanging of machines. No place in mainland Shanghai matches Cape Nanhui as a magnet to migrating birds. Cape Nanhui is one of the best birding hot spots in China, and it is not only completely unprotected, but it is also being actively destroyed. (Craig Brelsford)

But even as the Cape Nanhui we know falls, no one, to my knowledge, has hastened to reassure conservationists that areas in the newly reclaimed land will be set aside for birds.

In the city-province of Shanghai, which is the size of the U.S. state of Delaware, a few places have indeed been set aside, among them Chongming Dongtan. But those reserves are small, on remote islands far from mainland Shanghai, and practically unreachable by the millions of middle-class Shanghainese who lack a car.

Cape Nanhui, by contrast, is easily reachable from the city. And it is the one place where masses of bird lovers can conveniently get a taste of the grand spectacle that is spring migration along the east coast of the Eurasian supercontinent.

That opportunity is being taken away, not only from the birders alive today, but also from the birders of the future.

THE THRILL OF NANHUI IN MAY

Lesser Coucal takes off. Cape Nanhui, 14 May 2017. (Craig Brelsford)
Lesser Coucal takes off. Centropus bengalensis breeds in Earth’s greatest city. Recently, shanghaibirding.com examined Lesser Coucal and the other Cuckoos of Shanghai. (Craig Brelsford)

Our agony over the fate of Nanhui was tempered by the joy of birding. Orange-headed Thrush showed up Saturday at the Magic Parking Lot (30.884898, 121.968229). With the two vertical bars on its face, our specimen was either of race melli (breeds Guangdong, etc.) or courtoisi (Anhui).

On Sunday the Magic Parking Lot delivered singing Grey-crowned Warbler Seicercus tephrocephalus, and in Microforest 2 (30.926013, 121.970705) an appearance was made by Alström’s Warbler S. soror. Neither breeds in the region; both are very rare vagrants to Shanghai.

Iron Track (31.003613, 121.907883) gave us singing Yellow-breasted Bunting in full breeding finery and singing Pallas’s Grasshopper Warbler. I captured the latter’s song, rarely heard in Shanghai.

Pallas’s Grasshopper Warbler Helopsaltes certhiola, 13 May 2017, Iron Track (31.003613, 121.907883) (00:13; 2.1 MB)

The Marshy Agricultural Land (30.850707, 121.863662) near Eiffel Tower was highly productive, yielding Lanceolated Warbler, Forest Wagtail, and Striated Heron.

Varities of Eastern Yellow Wagtail. L: 'Green-headed Wagtail' Motacilla tschutschensis taivana. R: 'Alaska Wagtail' Motacilla tschutschensis tschutschensis. Both photographed within a few meters of each other dry rice paddies at Cape Nanhui, 13 May 2017. (Craig Brelsford)
Varieties of Eastern Yellow Wagtail. L: ‘Green-headed Wagtail’ Motacilla tschutschensis taivana. R: ‘Alaska Wagtail’ M. t. tschutschensis. Both photographed on dry rice paddies at Cape Nanhui, 13 May 2017. (Craig Brelsford)

Other highlights from Saturday along the 30-km stretch of coastline:

Yellow Bittern 2
Chinese Egret 14
Pacific Golden Plover 1
Pheasant-tailed Jacana 1
Black-tailed Godwit 17
Grey-tailed Tattler 2
White-winged Tern 260
Lesser Coucal 1
Common Cuckoo 12 singing
Tiger Shrike 4
Sand Martin ca. 300
Collared Finchbill 2
Arctic Warbler 5 singing
Thick-billed Warbler 1
Marsh Grassbird 2 singing
Forest Wagtail 1

Complete checklist here.

Sunday saw Jan-Erik and me note 78 species.

L-R: Jan-Erik Nilsn, Charles Wu, and 12-year-old birder Young Jack Han view Tiger Shrike in Microforest 4, 14 May 2017. (Craig Brelsford)
L-R: Jan-Erik Nilsén, Charles Wu, and 12-year-old birder Jack Han view Tiger Shrike in Microforest 4, 14 May 2017. (Craig Brelsford)

Highlights:

Japanese Sparrowhawk 1
Sharp-tailed Sandpiper 350
Dunlin 350
Oriental Pratincole 3
Little Tern 5
Hair-crested Drongo 8
Dusky Warbler 1
Taiga Flycatcher 1
Pechora Pipit 17 singing

Complete checklist here.

A DISCUSSION ABOUT SEICERCUS

Per's PDF
Some of the more challenging Seicercus warblers. This graphic was created by Shanghai Birding member Per Alström for a presentation he made to the Beijing Birdwatching Society in 2012. The PDF is downloadable through shanghaibirding.com.

Shanghai Birding is the WeChat companion to this Web site. Our members include everyone from persons brand-new to birding to some of the most knowledgeable birders in China. We discuss everything from the most common species to the most arcane.

Here is an edited transcript of a recent conversation on Shanghai Birding about the Seicercus warblers at Cape Nanhui:

Join Shanghai Birding for the very latest bird sightings in Shanghai.
Join Shanghai Birding for the very latest bird sightings in Shanghai.

Paul Holt: Can you post your recording of yesterday’s [14 May 2017] Alström’s Warbler as well please, Craig?

Craig Brelsford: Will post after I get home. Meanwhile, have you assessed the recording I posted yesterday morning? Do you agree it’s Grey-crowned Warbler? Jonathan Martinez, I’d like your view, too!

Craig Brelsford had earlier posted these sound recordings:

Grey-crowned Warbler Seicercus tephrocephalus 1/3, 14 May 2017, Magic Parking Lot (30.884898, 121.968229), Nanhui (00:36; 3 MB)

Grey-crowned Warbler 2/3 (00:49; 3.6 MB)

Grey-crowned Warbler 3/3 (01:08; 4.3 MB)

PH: Yes, Grey-crowned Warbler!

PH: For what it’s worth, while there are probably 30+ records of “golden-spectacled warblers” from coastal Hebei, very, very few have been as well documented as Craig’s and team’s recent Grey-crowned. Many have been photographed but far fewer sound-recorded. Alström’s is so far the only one so far known to breed north of the Qinling Shan (it’s a scarce and very local breeder at two, possibly three, sites in Beijing). Personally I’ve never seen soror in coastal Hebei (nor am I aware of any being sound-recorded there), but I have noted (and sound-recorded) 2 Bianchi’s S. valentini and 1 Martens’s S. omeiensis in coastal Hebei. I understand that the only (?) three coastal Hebei birds that have been captured and had their DNA compared have all been omeiensis. We’re very, very far from ascertaining the true statuses of these Seicercus in our area, but you perhaps should/might see more in Shanghai and coastal Zhejiang. As many of you already know, there are some excellent sound recordings of these on Per’s site.

CB: Great analysis, Paul, and great that you point out the resources on Per’s site. Jan-Erik and I got good sound recordings of the purported soror yesterday, and Charles Wu and I got some good shots, among them images of the outer tail feathers, which definitely had some white in them.

CB: Grey-crowned Warbler appeared in the microforests almost exactly a year ago: https://www.shanghaibirding.com/2016/05/20/great-records/

PH: Excellent, Craig. As you know they’ve all got white in their outer tails. Alström’s (aka Plain-tailed) doesn’t have much …

Alstrom's Warbler with splayed tail feathers. Craig Brelsford
Alström’s Warbler with splayed tail feathers. (Craig Brelsford)

CB: Right, Paul; thanks. The discussion yesterday was one of comparison and degree. How little must the white be in the tail, we were asking ourselves, for a Seicercus to “qualify” as Alström’s/Plain-tailed? Was the white in our photos a little or a lot? We ended up thinking a little, and that and the song we recorded led us to a determination of soror. I’ll post my photos and recordings as soon as I’m home.

PH: Personally, Craig, I find it very difficult to judge the amount and distribution of white on the tails of these Seicercus in the field and think that a good photo with the tail splayed would really be necessary. Even then, the differences are small and subtle. Tricky group!

Jonathan Martinez: Regarding the ID of these Seicercus, I have found that call is by far the easiest way to ID them. They all have a characteristic call. Some of them, like Alström’s or Bianchi’s, are usually quite vocal; others not as much. It requires much more experience or use of sonogram to ID them by song, but a few of them (Alström’s especially) include their call in their song, and some of them (Grey-crowned, Martens’s) include a trill in their song. Others do not (Alström, Bianchi’s). ID-ing them on plumage is, of course, a level up.

Alstrom's Warbler, Microforest 2, 14 May 2017. (Craig Brelsford)
Alström’s Warbler Seicercus soror, Microforest 2, 14 May 2017. (Craig Brelsford)

Here is the voice of the Alström’s Warbler that I recorded with my Olympus DM-650 pocket recorder:

Alström’s Warbler Seicercus soror 1/4, 14 May 2017, Microforest 2 (30.926013, 121.970705), Nanhui (00:50; 3.6 MB)

Alström’s Warbler 2/4 (00:08; 1.9 MB)

Alström’s Warbler 3/4 (01:08; 4.3 MB)

Alström’s Warbler 4/4 (00:41; 3.2 MB)

Featured image: Visiting British birder Mike May uses Craig Brelsford’s spotting scope to scan for birds at Cape Nanhui, Shanghai, 13 May 2017. (Craig Brelsford)

Comparing Richard’s and Blyth’s Pipit

Editor’s note: With more and more birders operating in Shanghai, more and more vagrant birds are bound to be discovered. One possibility is Blyth’s Pipit (photo above, L), a species similar to our familiar Richard’s Pipit (R). In this post, I will teach you how to separate the two.

2016 has been an outstanding birding year in Earth’s largest city. Paddyfield Warbler/Manchurian Reed Warbler, seen at Pudong’s Cape Nanhui on 18 Dec., was the latest in a parade of rare visitors seen in Shanghai in 2016.

The reason for the surge in good records, I am convinced, is more birders with better skills communicating more effectively. I am proud to say that shanghaibirding.com and the Shanghai Birding WeChat group have played a role.

In the Shanghai area, one species that has not yet been reported is Blyth’s Pipit. Anthus godlewskii breeds mainly in Mongolia, occurs on passage in central China, and winters mainly in India, so any records here would be of extralimitals. It is just the sort of vagrant that a bigger and better birding community could discover here in Shanghai.

Comparison of Richard's Pipit Anthus richardi "sinensis" (1) and Blyth's Pipit A. godlewskii (4). The putative taxon sinensis occurs in SE China S of the Yangtze and is the smallest population group within Richard's Pipit. Structurally it is similar to Blyth's Pipit. Note however the blackish centers to the median coverts (2, 3). In Richard's (2), the blackish centers are (a) diamond-shaped and (b) a bit fuzzy at the edges. In Blyth's (3), the blackish centers are squarish and more clearly defined. For years, Shanghai birders have been looking out for extralimital Blyth's Pipit. They are extremely rare or non-existent in the area. 1, 2: Nanhui, Shanghai, China, 15 Dec. 2016. 3, 4: Hulunbeier, Inner Mongolia, China, 22 July 2015. Craig Brelsford.
Comparison of adult-type Richard’s Pipit Anthus richardisinensis‘ (1) and adult Blyth’s Pipit A. godlewskii (4). The population group A. r. ‘sinensis’ occurs in southeast China south of the Yangtze River. Structurally, ‘sinensis‘ is the smallest group in Richard’s, with proportions recalling Blyth’s. Note however the blackish centers to the median coverts (2, 3). In adult-type Richard’s (2), the centers are triangular and tinged rufous at the edges. In adult Blyth’s (3), the centers are squarish, less rufous-tinged, and more clear-cut. 1, 2: Nanhui, December. 3, 4: Hulunbeier, Inner Mongolia, July. (Craig Brelsford)

The key to getting a Blyth’s in Shanghai is paying attention to the many Richard’s Pipit that we see in the area. Anthus richardi is more or less a passage migrant in the Shanghai area and is recorded here regularly in spring and autumn. Some are present in winter; Elaine Du and I had a “sinensis” last week, the ID’ing of which led to this post.

More views of Blyth's Pipit performing flight song. Alström writes that in flight, Blyth's Pipit 'often recalls one of the smaller pipits rather than Richard's' (237). 22 July 2015, Hulunbeier. Craig Brelsford.
More views of Blyth’s Pipit performing flight song, Inner Mongolia, July. In Pipits and Wagtails, Shanghai Birding member Per Alström et al. write that in flight, Blyth’s Pipit ‘often recalls one of the smaller pipits rather than Richard’s’ (237). Note however that Anthus richardi ‘sinensis,’ a population group within Richard’s Pipit often found in Shanghai, is structurally similar to Blyth’s. (Craig Brelsford)

Richard’s “sinensis” is very similar to Blyth’s, being best told by song, which is rarely heard in the Shanghai area. According to Per Alström et al., whose book Pipits and Wagtails is the authority on Palearctic and Nearctic pipits, the song of Blyth’s is “very characteristic and completely different from [that] of Richard’s” (242). During a trip in July 2015 to the Inner Mongolian prefecture of Hulunbeier, one of the few places in China where Blyth’s breeds, I recorded the song.

Blyth’s Pipit, flight song, recorded 22 July 2015 at a point (48.767866, 116.834183) near Hulun Lake, Inner Mongolia (2.1 MB; 00:32)

The calls of the two species also differ, but less markedly. The flight call of Richard’s is a common bird sound in Shanghai during migration season. The call of Blyth’s is similar enough to “cause problems even for some veteran observers” (Alström et al. 244). For Shanghai birders, even those unfamiliar with Blyth’s, a “Richard’s” with a strange flight call is worth your attention. Listen for what Alström et al. describe as a call “less harsh, softer and more nasal” than Richard’s (244). For reference, review the flight call of Richard’s:

Richard’s Pipit, flight call, Dishui Lake, Shanghai, 5 Feb. 2016 (00:01; 852 KB)

Regarding plumage, the most reliable differentiator of Richard’s and Blyth’s is the pattern of the median coverts. In Blyth’s, a typical adult-type median covert will show well-defined, squarish black centers. In Richard’s, the adult-type median coverts are less clear-cut, rufous-tinged, and triangular. Note that the fresher the plumage, the more reliable this differentiator is.

Another less reliable criterion is structure. Shanghai birders will agree that the first impression a non-“sinensis” Richard’s usually gives is “large pipit.” Other pipits, such as Buff-bellied Pipit, Red-throated Pipit, and Olive-backed Pipit, give a “small pipit” impression.

Richard's Pipit, Yangkou, Jiangsu, 5 Sept. 2014. Alström et al. urge birders to use care in ID'ing Blyth's and Richard's. Here, the median coverts of this Richard's appear squarish, like Blyth's (bottom R, inset). But note the date of the photo: 5 Sept., a time of year when most Richard's show worn plumage. The authors write: 'In worn plumage the shape of the dark centres to the secondary coverts is generally less obviously different, and the pale tips can be much the same colour in both species' (237). The ID of this Richard's was derived from its call, a more constant feature, and not from the appearance of its worn median coverts. Craig Brelsford.
Richard’s Pipit, Yangkou, Jiangsu, September. Alström et al. urge care in ID’ing Blyth’s and Richard’s. Here, the median coverts of this Richard’s appear squarish, like Blyth’s (bottom R, inset). But note the date of the photo: September, a time of year when most Richard’s show worn plumage. ‘In worn plumage,’ the authors write, ‘the shape of the dark centres to the secondary coverts is generally less obviously different, and the pale tips can be much the same colour in both species’ (237). The ID of this Richard’s was derived from its call, a more constant characteristic, and not from the appearance of its median coverts, a more variable characteristic. (Craig Brelsford)

Alström et al. say, and I having seen Blyth’s can concur, that a birder viewing Blyth’s will get a “small pipit” impression: “The smaller size, lighter build and shorter tail,” the authors write, “are often most apparent in flight, when [Blyth’s] often recalls one of the smaller pipits rather than Richard’s.” Note also that the smaller size and shorter bill, tail, and hind claw of Blyth’s give that species a “better proportioned” look than the larger and heavier Richard’s (237).

The directions above should be seen as guidelines; individual Richard’s and Blyth’s may defy easy categorization, “sinensis” Richard’s even more so. Alström et al. caution against jumping the gun with your ID: “It is crucial to realise that in both species (especially Richard’s) appearance can vary considerably in one and the same individual depending on mood, weather, etc.,” they write. “Also, some Richard’s are structurally very like Blyth’s; this is especially true of southern Chinese Richard’s (‘sinensis’)” (237).

A record of Blyth’s Pipit in Shanghai would shoot to the top of the “Year’s Best” list. The stakes are high, so look diligently, and use caution. Good luck!

BIBLIOGRAPHY

Alström, Per, Krister Mild & Bill Zetterström. Pipits and Wagtails. Princeton University Press, 2003. This landmark book, co-authored by Shanghai Birding member Per Alström, is my first reference on all things Motacillidae.

Brazil, Mark. Birds of East Asia. Princeton University Press, 2009. Serviceable descriptions of Blyth’s Pipit and Richard’s Pipit. Illustration of “sinensis.”

Svensson, Lars & Killian Mullarney & Dan Zetterström. Collins Bird Guide, 2nd ed. HarperCollins, 1999-2009. Outstanding illustrations of Richard’s Pipit and Blyth’s Pipit by Mullarney.

The Case for Conserving Cape Nanhui

Editor’s note: This tranquil scene is from Iron Track (31.003613, 121.907883), home of Reed Parrotbill and dozens of other species, and part of the large reed beds on the Dazhi River at Cape Nanhui. In the face of manic development, and in spite of being under no protection, Cape Nanhui conserves the best reed beds on the Shanghai Peninsula as well as mudflats critical to tens of thousands of migrating shorebirds. To save these treasures, Shanghai people must act now.

Who will save Cape Nanhui? Not foreigners like me, but the people of Shanghai. We foreigners are numerous in Shanghai and are disproportionately represented among the birders here. We can offer valuable perspectives. But if the people of Shanghai themselves do not wish to ensure a bright natural future for Cape Nanhui, then there is little that anyone can do.

I think that the people of Shanghai are ready for real conservation on the Shanghai mainland. Basic conservationist ideas have broad appeal, and an easily accessible, world-class, “people’s wetland reserve” at Cape Nanhui is a basic conservationist idea.

If I were Chinese and were arguing for a people’s wetland reserve for Cape Nanhui, then I would bring to light the following points.

SHANGHAI IS NOT A CITY IN THE CONVENTIONAL SENSE

The largest component of the city-province of Shanghai is the Shanghai Peninsula, a projection of land between the Yangtze River and Hangzhou Bay. Cape Nanhui is the tip of the peninsula, is a critically important stop for migrating birds, and is completely unprotected. A nature reserve at Cape Nanhui would form a third ‘stepping stone’ for birds crossing the Yangtze Delta, joining the reserves at Chongming Dongtan and Jiuduansha. Photo by NASA, customized by Craig Brelsford.
The largest component of the city-province of Shanghai is the Shanghai Peninsula, a projection of land between the Yangtze River and Hangzhou Bay. Cape Nanhui is the tip of the peninsula, is a critically important stop for migrating birds, and is completely unprotected. A nature reserve at Cape Nanhui would form a third ‘stepping stone’ for birds crossing the mouth of the Yangtze, joining the reserves at Chongming Dongtan and Jiuduansha. (NASA/Craig Brelsford)

Shanghai “市” isn’t really a city or a “municipality,” as 市 is often translated. It is a city-province, accountable to no government but the national government. The city-province is vast, covering an area greater than the U.S. states of Delaware and Rhode Island. Shanghai is twice as big as Luxembourg, half as large as Northern Ireland, and a third the size of Wales.

From a conservationist’s perspective, it is important to view Shanghai as a province and not a city, because cities are not usually thought of as being responsible for maintaining large nature reserves within their borders. Provinces, by contrast, are large enough to accommodate nature reserves.

I propose that, where workable, we stop referring to Shanghai as a city or municipality and start applying to it the more accurate label of city-province.

SHANGHAI OCCUPIES LAND UNUSUALLY IMPORTANT TO CONSERVATION

Reed Parrotbill. Far left: Yangkou, Rudong, Jiangsu, May 2010. Upper middle: Yangkou, October 2010. Bottom middle and far right: Nanhui, Shanghai, May 2016.
Reed Parrotbill is a a symbol of Shanghai and candidate for Shanghai Provincial Bird. Nowhere do the people of Shanghai have a better chance of seeing this Near Threatened species than in the reed beds at Cape Nanhui. Protection of the reed beds at Cape Nanhui would send a message to the world that Shanghai takes conservation seriously. (Craig Brelsford)

Any jurisdiction covering an area the size of a small country would be expected to conserve substantial amounts of its area. In the case of Shanghai, the call to conserve is even louder, because the area it occupies is unusually important for conservation. The Shanghai Peninsula is situated between the mouth of Asia’s greatest river and Hangzhou Bay. It is on the East Asian-Australasian Flyway and attracts tens of thousands of passage migrants representing a few hundred species.

Cape Nanhui is the tip of the Shanghai Peninsula and attracts passage migrants and winter visitors such as the Endangered Black-faced Spoonbill. Its large reed beds are the final stronghold on the Shanghai Peninsula of Near Threatened Reed Parrotbill, a candidate for Shanghai Provincial Bird, as well as Near Threatened Marsh Grassbird.

An abandoned sign about Ruddy Turnstone has been turned into a wall by a fisherman for his shack in the defunct nature reserve at Nanhui. 9 Nov. 2016. Photo by Craig Brelsford.
An abandoned sign about Ruddy Turnstone has been turned into a wall by a fisherman for his shack in the defunct nature reserve at Nanhui. (Craig Brelsford)

Cape Nanhui is completely unprotected; indeed, an attempt at a small wetland reserve has been shut down. The boardwalks and signs of the defunct reserve are crumbling, and the backhoes are standing by, waiting for the green light to smash what remains.

SHANGHAI, AN ENVIRONMENTAL UNDER-PERFORMER

No one is saying that Shanghai, a city-province of 26 million people, needs to create a Yellowstone. Any reasonable person understands the pressures the huge population of Shanghai puts on its natural resources.

Also, it must be pointed out that in the far-flung areas of the city-province, Shanghai has made an attempt at conservation. Chongming Dongtan preserves the eastern nub of Chongming Island, and Jiuduansha covers intertidal shoals near Pudong Airport.

Marsh Grassbird performing song flight at Nanhui, Shanghai, 10 April 2016.
Marsh Grassbird performing song flight at Cape Nanhui, 10 April 2016. The reed bed over which this grassbird was displaying is the largest at Cape Nanhui. It measures 1.4 sq. km and has its center at 30.876060, 121.945305. This reed bed is one of the last places on the Shanghai Peninsula where the song flight of Marsh Grassbird can be seen. (Craig Brelsford)

But Shanghai under-performs overall. Nowhere is the poor conservation performance more evident than in Pudong, the coastal city-within-a-city. Pudong is nearly double the size of Singapore and is half the size of Hong Kong. Yet the district contains zero wetland reserves on its mainland. Both Singapore and Hong Kong manage to hold in reserve significant portions of their territory.

The southeastern tip of Pudong is Cape Nanhui, a place that despite being under no protection still brims with natural treasures. No place on the Shanghai Peninsula has as many reed beds. The projection of land attracts birds making the long journey across Hangzhou Bay and the wide mouth of the Yangtze.

Moreover, Cape Nanhui is easily accessible to common people. It would be the perfect place for a world-class wetland reserve on the model of Sungei Buloh in Singapore and Yeyahu National Wetland Park in Beijing.

MORE INFORMATION

Craig talks to Pudong TV about the opportunities for conservation at Nanhui. Photo by Elaine Du.
On 12 Nov. 2016 I was interviewed by Pudong TV about the opportunities for conservation at Nanhui. (Elaine Du)

On shanghaibirding.com I have addressed the issue of conserving Nanhui:

Save the Nanhui Wetland Reserve! (cri de coeur plus call to action)
Remnants (preparation for probable demise of Cape Nanhui)
Reed Parrotbill, Symbol of Shanghai (naming Reed Parrotbill Provincial Bird of Shanghai will send a message about the importance of the reed beds such as those at Cape Nanhui)
Spoon-billed Sandpiper at Nanhui (proof of yet another endangered species using the defunct wetland reserve at Nanhui)
Will the Spoon Survive? (Nanhui is not the only area under threat. You ought to see the mess at Yangkou, Jiangsu. Conserving Nanhui will offset the losses elsewhere on the Chinese coast and will put a conservationist feather in Shanghai’s cap)
Meet Kai Pflug, Nanhui’s Mr. Clean (tribute to a birder doing his small part)

NEXT STEPS

We foreigners have had much to say about the future of Nanhui. I would like to hear more from Chinese. Is the case for a world-class wetland reserve at Nanhui convincing to you? If so, then what do you propose to do to bring it about?