ShareThis1 June 2010
Yellow Wagtails Motacilla sp. are beautiful birds, amazingly adapted for long-distance migration and with a variety of quite distinct species and races (or ‘subspecies’). All of them breed in the northern hemisphere and most migrate south to winter.
'Eastern' Yellow Wagtail: Motacilla tschuschensis (adult). Photographed in February at Leanyer Sewage Farm by Trevor Collins.
Most of the birds that occur in Australia are of three ‘types’, in terms of what they look like (rather than taxonomy – see below):
- Eastern Yellow Wagtail: Motacilla tschuschensis (Eastern).
- Green-headed Wagtail: M. taivana (previously M. f. taivana).
- ‘Dark-headed’ forms, M. sp. subspecies macronyx or M. flava thunbergi.
Yellow Wagtails can turn up just about anywhere in Australia but always in quite rich open-country habitats with disturbed ground and some water. Sewage farms, dams and grassy margins to lakes are all potential habitat.
'Eastern' Yellow Wagtail: Motacilla tschuschensis. Photographed in February at Leanyer Sewage Farm by Trevor Collins.
The ‘Eastern Yellow Wagtail’ is by far the most commonly occurring. They are annual in northern Australia, sometimes turning up in quite big numbers around Broome and Darwin early in the year. They have been found as far south as the Western Treatment Plant in Melbourne and far southern Western Australia. Eastern Yellow Wagtails are relatively simple to identify. Adults and juveniles have a bold white eye stripe. Juveniles have thick bold wing patterning but lack the slaty grey head of the adult. The base colour ranges from an off-white in juveniles to brilliant yellow in adults.
The dark-headed forms are a continued source of confusion for identification, although they are both considered amongst the 13 races that are “strongly polytypic” (Alstrom and Mild (2003) – in other words, these are truly different birds. It may be that most non-breeding forms of ‘Grey-headed’ or ‘Western’ (thunbergi) and ‘Manchurian’ (macronyx) Wagtails are virtually inseparable. In this article, we refer to them in combination as ‘dark-headed wagtails’, use ‘western’ for thunbergi and ‘Manchurian’ for macronyx.
An armchair tick
Recently elevated to a full species but worthy of mention (as some authorities still consider it a race of yellow wagtail), is the Green-headed Wagtail Motacilla taivana. Birders fortunate-enough to have seen this species already were granted an extra bird on their Aussie list without even having to leave the house!
Green-headed Wagatils occur regularly enough in Australia but are still rare. This is a strikingly patterned species, contrasting deep forest green and bright golden markings in adults. It presents little confusion for identification (images: 1, 2, 3).
Dark-headed Wagtails
Manchurian Yellow Wagtails are undoubtedly the most regular of the two dark-headed wagtails to occur in Australia. They are known to migrate into south-east Asia and they breed in China. Despite their similarity to the Western (thunbergi) race, these may be more closely related to Green-headed Wagtail (taivana), which breed in similar areas. However, authorities such as Alstrom & Mild do not conclude which species they are related to. It suffices to say that we don’t yet know precisely where macronyx sits in the Yellow Wagtail taxonomy.
Western Yellow Wagtails however, breed right across far northern Siberia to northern Europe and are part of the Motacilla flava group. Birds from the far east appear to cross the Himalayas, migrating into southern Central Asia and northeast Africa. European birds head south into similar areas.
These are the current known / suspected records of dark-headed wagtails for Australia in:
- Bakers Lagoon, NSW, Apr-May 1979
- Eyre Bird Observatory, Aug 1984 (unconfirmed)
- Christmas Island, Apr 2004
- Cocos Keeling, May 2005
- Broome, Dec 2007
- Darwin, Feb 2008 (see below)
- Cocos Keeling May 2010 (see below)
There is general agreement, both past and present (e.g. Phil Round, Craig Robson and Pam Rasmussen) that Manchurian Yellow Wagtails are the most likely to occur in Australia. For example, Voous (1950) (In Higgins et al. 2006) identified 0.5% of skins collected in Malaysia and Indonesian Arch as this species. So based on Voous, we might expect only 1 in 200 yellow wagtails reaching Australia to be Manchurian.
Despite their adaptation for long-distance flight, Yellow Wagtails will usually migrate less than 7,000km to wintering grounds. Some individuals do of course go further and the appearance of Yellow Wagtails in southern Australia and also South Africa, is testament to that. Nevertheless, migration over tropical forest is an exception to the rule of migration and the majority will winter north of the equator, because of competition for food in tropical forests.
Vagrancy is a different matter. The ‘Western’ Yellow Wagtail has always been considered a candidate for vagrancy into Australia … any migrant that travels these distances is possible … but its natural breeding range is a long way north. It would have to travel a staggering 12,000km to reach the tip of Australia. To date, this race has not been confirmed for anywhere in south-east Asia but a record by Richard Baxter on Cocos Keeling could potentially be this species (see below).
Identification of dark-headed Wagtails
| Feature | Western thunbergi | Manchurian macronyx |
| Crown | ad m in spring has crown dark grey (often tinged a little bluish in fresh plumage) [1] Mid-grey (ad m) [5] Non-breeding. Head much duller (more concolorous with upperside [5]. | slightly paler, cleaner grey forehead to nape (ad breeding m); non-breeding m head duller (more concolorous with upperside) [5]. Ad f breeding, duller less blue-grey top of head and neck. |
| Ear coverts / lores | ear coverts very dark grey or blackish [1] Rear head sides mid-grey; blackish-grey face to ear coverts distinctive [5] Blackish-grey of lores typically extends onto forehead [5] | darker head sides [3] blackish-grey of lores usually not extending up onto forehead; slightly cleaner grey (less extensively blackish-grey) ear-coverts [5] Contrasting blackish area typically restricted to lores and anterior ear coverts and merging into grey rest of ear coverts. [6] At best have only faint pale arc around eye.[6] Ad f breeding, paler less contrasting ear-coverts. |
| Nape | (bluish) grey, not reaching far back to upper mantle; grey of nape wearing to greyish-black in some very worn summer birds; no sharp demarcation between dark grey nape and paler greenish mantle. [1] Mid-grey [5] Non-breeding. Head much duller (more concolorous with upperside [5] | slightly paler, cleaner grey forehead to nape (ad breeding m); non-breeding m head duller (more concolorous with upperside) [5] |
| Eye / supercilium | Usually no white above eye at all. No dark eye-crescents. Sometimes a tiny patch over or immediately above eye, rarely a little longer white streak but not a full supercilium.[1]. Narrow whitish supercilium in 1st-winter [2],[3] Supercilium absent in adult male [2]. Lacks supercilium, or shows short whitish one behind eye (ad m) [5]. Recorded absence of eye-stripe in only 60% of Swedish thunbergi, and the rest with short white supercilium also regarded as good thunbergi [4]. | No supercilium [3]. Typically lacks any supercilium (ad m) [5]. Female breeding, typically shows narrow whitish supercilium [5], [6]. Ad m breeding, lack prominent white supercilium, though some birds apparently have narrow whitish supercilium.[6] |
| Upperparts | Olive-green [3]. Grey-tinged olive-green upperparts [5]. Female breeding, upperparts dull greyish- to brownish-olive[5]. | Tends to be brighter and greener above [5] |
| Underparts | Yellow underparts (throat whiter); sometimes has necklace of darkish flecks across upper breast [5]. Non-breeding, underparts whiter [5]. Female duller and less extensive yellow below [5] | Yellower lower throat [3]. Slightly cleaner yellow underparts appear to only rarely show dark- spots [5]. Female duller and less extensive yellow below [6]. |
1. Svensson 1992; 2. Grimmett et al. 1999 3. Robson 2000 4. Rendahl 1967 (in Lundwall & Persson 2006); 5. Robson 2000 (2nd ed. Draft text); 6. Higgins et al. 2006.
Possible Australian Records
The Darwin Bird – possible macronyx?Darryel ‘Biggles’ Binns, Simon Mustoe and Trevor Collins (photos from original description, by Trevor Collins). Darwin, Leanyer Sewage Works, 9-11 Feb 2008. The bird was originally seen in relatively poor light on the 9 February just after the start of the north west monsoon and following a torrential downpour. The faint supercilium was not evident and the underparts looked plainly pale yellow. As a consequence of the rain, the bird was wet and there was little observable fringing on the wing feathers, apart from a pale edge to the base of the closed wing. The ⅔ grown outer tail feathers were noted at the time, confirming that the bird photographed on 11 February was the same individual. The bird was present with up to about 20 tschutschensis Yellow Wagtails.
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 Bird resembling 'Manchurian' Yellow Wagtail: Motacilla flava macronyx. Photographed in February 2008 at Leanyer Sewage Farm by Trevor Collins.  Bird resembling 'Manchurian' Yellow Wagtail: Motacilla flava macronyx. Photographed in February 2008 at Leanyer Sewage Farm by Trevor Collins. |
The Cocos-Keeling bird – possible thunbergi?Richard Baxter. Cocos Keeling, May 2010. Bird seen on Cocos Keeling in May 2010. Seen reasonably well but difficult to photograph.
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 Bird resembling 'Western' Yellow Wagtail: Motacilla flava thunbergi (click to enlarge). Photographed May 2010 on Cocos Keeling by Richard Baxter. |
References
Alström, P. & Mild, K. (2003) Pipits and Wagtails Princeton University Press, Princeton, New Jersey.
Christidis, L. and Boles, W.E. (2008) Systematics and taxonomy of Australian birds. CSIRO Publishing.
Svensson, L. (1992) Identification Guide to European Passerines British Trust for Ornithology, Thetford, Norfolk.
Grimmett, R., Inskipp, C. & Inskipp, T. (1999) Birds of the Indian Subcontinent Christopher Helm, London.
Robson, C. (2000) A Filed Guide to the Birds of South-East Asia New Holland, London.
Rendahl, H. (1967) Verbreitung und Zugverhältnisse der schwedischen Schafstelzen. Ark. Zool., 2(20), 381-408.
Higgins, P.J., Peter, J.M. & Cowling, S.J., eds. (2006) Handbook of Australian, New Zealand and Antarctic Birds. Volume 7. Boatbill to Starlings. Part B Dunnock to Starlings Oxford University Press, Melbourne.
