Wader Wednesday ID CHALLENGE 18 November 2020: P Plate by Jannette Manins & Janine Duffy
Who is this elegant bird? Seen and photographed by Peter & Jannette Manins on the Cairns, QLD foreshore.
Size: medium.
Solution:
Non-breeding Common Greenshank Tringa nebularia
A long-legged, medium-sized wader with a straight bill could only be a greenshank, marsh sandpiper, or dowitcher. Redshanks are ruled out by the yellow legs, and godwits are too large, have longer bills and have dark legs. Asian Dowitcher has a much longer bill than this bird, and also has dark legs.
So its either a Common Greenshank or a Marsh Sandpiper, both of which are reasonably common in Cairns and most Australian coastlines.
How to tell these two apart? They have much in common and just a few defining features. The first is size, but that’s really hard to judge when you only see one.
Greenshanks are larger, chunkier, with a deeper stronger bill. They have streaky plumage on their crown, neck and shoulders. They have a white forehead, but not much of a supercilium. It seems to me that the depth of the bill at mid-point is similar to the diameter of the eye.
Marsh Sandpipers are smaller, slimmer with a very fine needle-like bill. Their plumage is “smoother” (ie not streaky), and more solid grey on the crown and neck. The white supercilium (eyebrow) is usually more noticeable on this species (though this is sometimes a bit hidden in strong light). The depth of the bill at mid-point is smaller than the diameter of the eye.
There’s also those barred edges to the covert and secondary/tertiary (upperpart) feathers. On a good view, or a great picture like this one, its really noticeable. Marsh Sandpiper don’t have that.
In flight the underwing of the Greenshank is dark streaky, while the Marshie is a smoother vignette of light grey to white. The upperwing of the Greenshank is dark-streaked overall, and the Marshie is a smooth mid- grey to black tips
Maybe think “Green-streaky” and “Marsh Smoothie”
eBird: https://ebird.org/species/comgre
Great pics and story here: https://wingthreads.com/meettheshorebirds/common-greenshank/
Learn more/conservation status: https://www.birdlife.org.au/bird-profile/common-greenshank
http://www.nzbirdsonline.org.nz/species/common-greenshank
Women Birders Australia 