Bar-tailed godwit – Limosa Lapponica
is a relatively short-legged species of godwit. The bill-to-tail length is 37–41 cm (15–16 in), with a wingspan of 70–80 cm (28–31 in). Males average smaller than females but with much overlap; males weigh 190–400 g (6.7–14.1 oz), while females weigh 260–630 g (9.2–22.2 oz); there is also some regional variation in size (see subspecies, below). The adult has blue-grey legs and a very long dark bill with a slight upward curve and pink at the tip. The neck, breast and belly are unbroken brick red in breeding plumage, off white in winter. The back is mottled grey.

It is distinguished from the black-tailed godwit (Limosa limosa) by its barred, rather than wholly black, tail and a lack of white wing bars. The most similar species is the Asiatic dowitcher.

The bar-tailed godwit migrates in flocks to coastal East Asia, Alaska, Australia, Africa, northwestern Europe and New Zealand, where the sub-species Limosa lapponica baueri is called ‘Kūaka’ in Māori.

It was shown in 2007 to undertake the longest non-stop flight of any bird. Birds in New Zealand were tagged and tracked by satellite to the Yellow Sea in China. According to Dr. Clive Minton (Australasian Wader Studies Group): “The distance between these two locations is 9,575 km (5,950 mi), but the actual track flown by the bird was 11,026 km (6,851 mi). This was the longest known non-stop flight of any bird. The flight took approximately nine days. At least three other bar-tailed godwits also appear to have reached the Yellow Sea after non-stop flights from New Zealand.”

One specific female of the flock, nicknamed “E7”, flew onward from China to Alaska and stayed there for the breeding season. Then on 29 August 2007 she departed on a non-stop flight from the Avinof Peninsula in western Alaska to the Piako River near Thames, New Zealand, setting a new known flight record of 11,680 km (7,258 mi).

It sounds like this
Recording by Andrew Spencer from Xeno canto