Inland Dotterel plumage variation

[Wallaces <>]

Since seeing a group of 14 Inland Dotterel near Quandialla on Tuesday, I have been trying to understand the plumage variation I saw. There is plenty of variation visible but is it just individual plumage variation or due to differences in age, sex or breeding condition. Instead of helping, the descriptions in the usual references are more inconsistent than for any other species I can recall - see table below.

 

The clearest difference shown in the attached picture is that some have a white face and the area around the ‘Y’ while other birds have a tan face and area around the ‘Y’. The colour on the back also varies with some birds having  brown centres to their feathers surrounded by a tan colour with others have black centres to the feathers with a more whitish/grey surrounds. In some the black areas are not as defined as they are on other birds.

 

If anyone has more experience with this species (this is my first encounter) or any other information which could help understand the variation, I would appreciate knowing.  Video of the birds http://www.hbw.com/ibc/1424277.

 

Thanks

 

Steve

 

Source	Male/Female	Breeding/non breeding	Immature/Juvenile
The Australian Bird Guide (2017)	No difference described	NB - Dark lines through eyes and on underparts become duller and fainter, may be completely lost from underparts	J – duller than adult non-breeding, with pale centres to feathers of upperparts
Waders by Hollands and Milton (2012)	Female: similar [to male] but duller	Similar	J - Duller. Black ‘halter’ indistinct or absent.
Bird in the Hand (v2) (information source - HANZAB) (extracted from http://www.absa.asn.au/ 12 Sep 2017)	Female: Black and over crown and strip below eyes mottled by buff. ‘Y’ on breast narrower than male & less clearly defined with broad buff edges to feathers;	No difference described	J – orange-brown to orange buff with no “Y”, to indistinct traces of a “V” (not “Y”) Second immature - mottled untidy looking “Y” with buff edges to feathers
Birdlife Australia website (20 Oct 2017)	No difference described	No difference described	J - duller, paler and less streaked with little or no black markings evident
Handbook of birds of the world (www.hbw.com accessed 20 Oct 2017)	Sexes alike	NB - apparently almost lacks the eye-bar and breast band	J - like non-breeding adult, i.e. showing just traces of dark face and collar.
The Field Guide to the Birds of Australia, Pizzey and Knight (8th edition 2007)	No difference described	No difference described	I – breast marking indistinct or is plain buff-white below, running to chestnut on flanks
Field Guide to Australian Birds, Morcombe (2000)	No difference described	NB – may show some loss of colour but distinctive dark markings … always present	J – probable that all birds in pale plumage are juveniles.

 

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