Dr Nial Moores, Nationwide Director, Birds Korea, January twenty fifth 2025.
Shrikes will be among the many best species to determine (grownup males in breeding plumage, for instance), or will be among the many most tough, because of a mix of seasonally totally different plumages and naked elements’ coloration, sexual dimorphism, extremely advanced and different moult methods, taxonomic uncertainties and hybridization. This put up goals to introduce among the options used to determine the Republic of Korea’s first Pink-tailed Shrike Lanius phoenicuroides.
On December 22nd 2024, Ms Lee Yunha, a Center Faculty pupil, seen an odd-looking shrike at a preferred birding spot in Gimpo, Gyeonggi Province. On January 11th 2025 a number of birders visited the positioning, together with Birds Korea member Dr Sung Soyoung (whose photographs are used right here) and Dr Park Jong-Gil, the lead ornithologist with the Korean Nationwide Parks. The shrike was nonetheless current, and confirmed extraordinarily effectively.
I used to be despatched a number of wonderful photos and opinions on this shrike; and in addition noticed different photos posted on-line over the following few days, all taken in sturdy winter sunshine with wonderful cameras, as an increasing number of birders visited the positioning. Due to the kindness of a number of Birds Koreans I used to be then in a position to go to the positioning and see the shrike on January twenty second (precisely a month after the primary commentary), when a mix of dense yellow mud and hazy, flat sunshine supplied fascinating situations for assessing plumage tones.
The “Gimpo shrike” is clearly a member of the closely-related “tremendous species” (Svensson 1992) group comprising Brown Shrike Lanius cristatus (a domestically frequent migrant by means of the ROK and really native breeder, with information usually spanning late April to early October, and no adequately documented mid-winter information on the mainland); Pink-backed Shrike L. collurio (fewer than ten Korean information and none in winter); Isabelline Shrike L. isabelllinus (two earlier Korean information, on August 25th 2022 in Seosan and in December 2023 within the Saemangeum reclamation space); and Pink-tailed Shrike L. phoenicuroides (a species typically referred to as Turkestan Shrike, beforehand unrecorded in Korea, with no information on eBird in jap China, on the Korean Peninsula or in Japan).
Adjustments over latest a long time within the taxonomic therapy of those species reveal the issue of the ID problem. Svensson (1992) didn’t acknowledge the cut up of Pink-tailed from Isabelline whereas Panov et al. (2011) in Pyle et al. (2015) take into account that Pink-backed and Turkestan could also be one organic species, based mostly on their intensive hybridization.
Quick impressions from photos means that the Gimpo shrike superficially seems to be like a Brown Shrike, with pretty darkish brown and in some lights grey-brown upperparts, a barely brighter tail and crown, and a quite contrasting head sample, with an apparent supercilium and darkish ear coverts.
The chook can rapidly be aged too as a First-winter, due to e.g., the small darkish subterminal bars on the retained juvenile larger coverts and the small black markings close to the tip of the tail. Though First-winters are essentially the most difficult age group to determine, vermiculations (wavy bars) proven most prominently by juveniles and First-winters, and once more usually by females in mid-winter, will be useful in narrowing the identification course of considerably (Worfolk 2000).
In January, the Gimpo shrike has apparent vermiculations on the flanks and uppertail coverts and rump. Though moults are extraordinarily difficult in these species, the extent of those markings can be very uncommon in Isabelline (which normally reveals nearly none by mid-winter) and doubtless of Pink-backed, which is likely to be anticipated to point out extra such markings on the upperparts, together with e.g., on the crown.
Based mostly merely on these vermiculations, the three most certainly identifications for the Gimpo chook due to this fact turn out to be Brown Shrike or Pink-tailed Shrike or a hybrid.
Wanting extra intently, the chook’s construction confirms the chook shouldn’t be a “pure” Brown Shrike. In discipline situations particularly, the invoice invariably seems to be lengthy and slender (whereas in some photos, the invoice seemed quite heavier); the pinnacle seems to be fairly small; the legs look fairly lengthy; and the tail is clearly shorter than is likely to be anticipated in Brown, although longer than can be anticipated in a Pink-backed. These are all structural impressions anticipated in Pink-tailed or Isabelline, and assist to provide the chook a really totally different really feel in discipline situations to a Brown Shrike.
As well as, in each photos and within the discipline, the tertials look clearly shorter than in Brown, revealing a medium-length main projection with six or so main ideas seen – rapidly ruling out most “pure” Pink-backed Shrike (which usually present 7 or 8) and the overwhelming majority of Brown Shrike (which regularly proven solely 5, although can not often present 6 and even 7 – maybe because of hybrid affect?).
Seen in photos too, the all-important main formulae (the relative size of every main) proven by the chook in flight can also be an excellent match for Pink-tailed Shrike. This in response to a comparability with Svensson (1992) and skilled evaluation of photos by Dr Park Jong-Gil. As well as, the shortage of white although with some paling on the main bases appears to be good for a feminine Pink-tailed Shrike in her first winter of life.
Due to this fact, even earlier than wanting in any element at plumage tones, the most certainly contender for this shrike is Pink-tailed Shrike.
Worfolk (2000) checklist a number of plumage options that can be utilized to determine First-winter Pink-tailed Shrike, whereas additionally advising that, “It shouldn’t be thought that each chook will be recognized. Whereas many first-winter isabelline shrikes clearly present options of both phoenicuroides or isabellinus, a major share (in all probability greater than 10%) seems to be intermediate. These could certainly be of combined parentage or it could be that one or each taxa are extra variable than their grownup plumage would counsel” (Worfolk 2000).
Options in help of identification of Pink-tailed would come with “earth-brown to pale sandy-grey upperside contrasting with the predominantly whitish underside” and as First-winters resemble females in lots of options, “a barely hotter tone to the crown” and, “a rufous rump contrasting with the extra drab mantle” (Worfolk 2000).
Plumage tones in First-winter shrikes will be remarkably tough to evaluate effectively from photos, because of e.g., variations in gentle situations and even digicam gear (see Pyle et al. 2015). In most photos (e.g. in Figs 1 & 2), the Gimpo shrike seems to be brown above and flippantly buff-washed under, with an clearly hotter crown and rump and contrastingly paler underparts (i.e., as anticipated in Pink-tailed Shrike). In discipline situations and in some photos taken on January twenty second (e.g. Figs 11 & 14) , the chook seemed a lot brighter above, particularly on the crown, and in head-on views with flat gentle, the underparts confirmed buff flanks and off-white underparts – a lot too pale for Isabelline.
The chook due to this fact matches Pink-tailed Shrike effectively.
Can a hybrid origin be sufficiently excluded in order that Pink-tailed Shrike will be added to the nationwide checklist?
Most likely essentially the most detailed evaluation of hybrid shrikes within the literature will be present in Pyle et al (2015). This paper units out in typically painstaking element the method of figuring out a shrike from this similar “super-species” group which was present in Mendocino in California.
The Mendocino shrike was present in March and remained into April, throughout which period moult of key feather tracts progressed quickly, permitting the preliminary suspicions of hybrid origin to be kind of confirmed. Essentially the most affordable identification was Pink-backed x Pink-tailed (referred to as Turkestan within the paper). This meant that the Mendocino shrike holds “the excellence of being the one particular person chook to characterize two species new to North America.” (Pyle et al. 2015). Initially, the obvious anomalies had been a mix of gray wash on the crown and nape (initially that means the chook was recognized as a lucionensis Brown Shrike) however heat brown upperparts; some trace of darkening within the central tail feathers; and a construction that didn’t match in any respect effectively with Brown Shrike.
Some photos of the Gimpo shrike steered a greyish wash on the nape and in addition darker edges to among the tail feathers, as proven in a picture taken on January twenty second.
Subject views eliminated these suspicions. The greyish wash on the nape “rippled” with the angle, typically seeking to cowl the mantle, and at different angles disappearing totally. As well as, the suspected darker edges to among the tail feathers steered in some photos additionally disappeared because the angle modified. For now, any “distinction” within the tail seems to be merely to be the results of a mix of shadow and fewer put on than proven by extra uncovered elements of the identical feather.
In an analogous manner too whereas the tail seems to be fairly uninteresting in most photos, within the discipline, the underside glows orange when catching the sunshine – one other very sturdy function in help of identification as Pink-tailed Shrike. The underparts additionally look actually fairly pale (buff on the flanks and off-white on the stomach), and even the vermiculations look a lot finer and extra delicate grey-brown (spider’s web-like) than steered by photos. All these options match Pink-tailed Shrike effectively.
One other preliminary concern about this chook associated to a number of small darkish markings on the tail, shared by juveniles of all of the shrikes on this “super-species” group. Though largely worn away, in excessive decision photos they present as a slender “V”, set off by a quite broad wedge of white, particularly on t6 on the proper facet of the chook. Usually, Brown has the least intensive black and the least distinction on t6; and Pink-backed essentially the most. Svensson (1992) depicts two variants within the latter species – one broad with a slender level and a wedge of white, and the opposite a lot narrower and extra curved, with a white fringe of even width. The one illustration of Isabelline / Pink-tailed in Svensson (1992) reveals a reasonably broad black band, with a broad tip, and no apparent white wedge. Are these troubling tail markings higher for Pink-backed than for Pink-tailed? And if mixed with different anomalous options, are they sufficient to counsel hybrid affect?
Luckily, Pyle et al. (2015) consists of photos of specimens of all 4 species. Though the pale border in t6 of the Gimpo chook is a bit more intensive than anticipated, maybe matching Pink-backed Shrike extra intently, the darkish markings themselves match a specimen of Pink-tailed Shrike very effectively (Determine 14, web page 23).
The coloration of ear coverts is maybe the one potential anomaly that continues to be to be addressed. In most photos and sometimes within the discipline, the ear coverts seemed very darkish brown, sometimes exhibiting chestnut at sure angles. They due to this fact match Pink-tailed Shrike. In discipline situations, nevertheless, there have been additionally instances when the ear coverts seemed nearly concolorous with the crown, and these impressions had been supported by among the photos taken on the similar time (e.g., Determine 14). Worfolk (2000) states that, “The ear-coverts seem like by no means as rufous as is typical in” Pink-backed Shrike. Relatively than checklist this as an anomalous function, within the absence of any contradictory info, it is likely to be wiser to amend Worfolk’s textual content to one thing nearer to “by no means look constantly, at a number of angles, as rufous as is typical in Pink-backed Shrike” .
There are plans to catch the chook and to take DNA to verify the identification. This could resolve this identification even additional. One other much less worrying manner (each for the chook and for the banders!) would possibly merely be to attend for the chook to moult, in order that different plumage options turn out to be higher; or maybe to pattern droppings.
Both manner, until strongly contradicted by DNA evaluation, there isn’t a longer any compelling purpose to doubt the identification of the Gimpo shrike as a Pink-tailed Shrike, as additionally acknowledged in lit. on January 18th by Grahame Wallbridge and Brian Small after reviewing among the photos.
We are going to due to this fact add Pink-tailed Shrike in our subsequent revision to the Birds Korea Guidelines (which we’re actively enterprise…). And as an eBird reviewer, I’ll approve information of the Gimpo shrike on eBird as Pink-tailed Shrike. I may also attempt to return to see this typically subtly stunning and at different instances dazzling shrike in March or early April!
Within the meantime, I wish to end this put up by congratulating Ms Lee Yunha warmly for turning into the youngest birder ever to discover a nationwide first in Korea! Fantastic!
(Lastly, as all the time, please tell us if there are any errors or misrepresentations on this put up in order that we will right them: thanks).
Acknowledgements
My honest thanks go particularly to Dr Sung Soyoung for permission to make use of his great photos; to Dr Park Jong-gil for his preliminary ID and skilled feedback; to Dr Shim Kyu-Sik for his encouragement and persuasion to journey as much as Gimpo to see this chook; and to Dr Bernhard Seliger and Dr Choi Hyun-Ah for allowing me to hitch their common survey in Gimpo, which included the world with the shrike, and for sharing of photos. Many thanks too to Grahame Wallbridge for his emails, and for relaying his and Brian Small’s skilled opinion on the identification.
Additional Studying:
References
Pyle, P., Keiffer, R. J., Dunn, J. L. & Moores, N. 2015. The Mendocino Shrike: Pink-backed Shrike (Lanius collurio) x Turkestan Shrike (L. phoenicuroides) hybrid. North American Birds. Vol, 69 (2015). Number one, pages 4-35.
Svensson, L. 1992. Identification Information to European Passerines. Fourth Revised and Enlarged version. Stockholm, 2014.
Worfolk, T. 2000. Identification of red-backed, isabelline and brown shrikes. Dutch Birding 22: 323-362, 2000
