The entire world population was one gravid [pregnant] female in 1930.
Restricted to remote Laysan Island about 800 miles northwest of Honolulu. A 914-acre island with a central lagoon is home to the small teal which was not described until 1892.
Guano harvesters occupied the island between 1891 and 1904 and preyed heavily on the teal reducing the bird to less than a hundred by 1904. Japanese albatross plume hunters arrived in 1909 and further decimated the remnant population.
However, the paramount reason for their near extinction was the introduction of rabbits in 1902 by the guano company's manager. The rabbits did their thing and virtually denuded the small island of all vegetation depriving the teal of food and cover for nesting.
A mere 6-7 Laysan Teal remained in 1911 but this appallingly low figure was huge when compared with the single gravid female that remained in 1930.
An experienced biologist spent 16 days on the denuded island in 1930 and could only find one pair with a nest that had been recently destroyed by a Bristle-Thighed Curlew. The drake subsequently disappeared but sufficient semen was retained in the female's oviduct to produce another fertile clutch.
The entire world population, today, came from this one lone duck.
The rabbits were finally eradicated in 1923. The teal population rebound was remarkable to as many as 700 but stabilizing at about 500 ducks. Then low water levels, scarcity of brine flies and an outbreak of parasites reduced their numbers again. A survey in 1995 indicated that 160 birds were present on the island.
Since the first captive breeding of Laysan Teal in 1959 they are fairly common in waterfowl collections. A single pair acquired by the Waterfowl Trust in 1958 was responsible for over 400 descendants.
Laysan Teal exhibit a great deal
of individual variation with respect to the white on the head.
Young birds just a little around the eye, older birds may have
a mostly white head.