The sexes were alike; downy young were black all over, with conspicuously long dark legs and a yellow bill, and immature birds had the entire underside colored pale brown.

[3] It was endemic to Laysan (although an introduced population was present on Midway Atoll for some decades early in the 20th century); some authors have noted that there were tales of flightless rails on other Hawaiian islands, but they refer to local forms extinct before Western contact.

The Laysan rail was an opportunist that fed mainly on invertebrates such as moths, Neoscatella sexnotata (brine flies), blowflies, and their larvae; plant leaves, seeds, and eggs and carcasses of seabirds were eaten when they were available.

It was an aggressive bird that would fight off other species, particularly the Laysan finch: the latter is very adept at breaking open seabird's eggs to consume the contents, while the rail was much less so.

They were nimble and restless, retreating to the tussocks to avoid predators, but chiefly to escape the mid-day heat; if they felt threatened, they often hid in the burrows of petrels.

In courtship or territorial defense (reports are not clear, but probably the latter) two birds would stand opposing each other, fluffing up their plumage, and give rattling, scolding calls not unlike a mechanical alarm clock.

[6] Soon after dusk, the entire population could be heard to engage in a brief bout of vocalization, which Frohawk (1892) described as sounding like "[...]a handful or two of marbles being thrown on a glass roof and then descending in a succession of bounds.

bryanii, kāwelu (Eragrostis variabilis) and introduced Bermuda grass (Cynodon dactylon) around the lagoon, while on Midway, it nested in any shelter that seemed convenient, such as naupaka kahakai (Scaevola taccada ) thickets and pōhuehue (Ipomoea pes-caprae subsp.

The nests were placed on the ground or inside the base of a tussock; in the latter case the birds would rearrange the dried dead leaves to form a roofed cavity reached through a small tunnel some 15 centimetres (5.9 in) long.

In the 1900s, when destruction of the vegetation by the rabbits had only just started, the rail's population was around 2000 mature birds and at carrying capacity; it remained so until at least the early 1910s, but declined thereafter.

[5] The species is believed to have become extinct on Laysan during 1923, probably mainly because no habitat for nesting was left in sufficient quantity to maintain the population and also due to rats being introduced to the area in 1944.