Alaotra grebe
The Alaotra grebe, also known as Delacour's little grebe or rusty grebe, is a recently extinct grebe that was endemic to Lake Alaotra and its surrounding lakes in Madagascar. Experts say that the grebe became extinct after carnivorous fish were introduced into its native habitat. The last sighting of the Alaotra grebe was in 1983 or 1985 and it was officially declared extinct in 2010.
Description
The grebe was about long. Its ability to fly long distances was restricted because of its small wings. It exhibited no marked sexual dimorphism, although males were slightly larger than females.Diet
The Alaotra grebe fed mostly on fish, although insects were found in the stomachs of a few specimens. Its hefty bill was considered typical of a piscivorous grebe.Breeding
The breeding behavior of the Alaotra grebe was largely undocumented. Because little and Alaotra grebes were able to successfully pair off, it is suspected that courtship and pair formation took place in December, while most breeding activity took place between January and March. However, based on some observations of older juveniles with their mothers in late May and early June 1929, it is suspected that some egg laying must have occurred in April to June. Otherwise, the behavior of this grebe is undescribed, although it is suspected to have behaved similarly to the closely related little grebe.Extinction
The species declined in the course of the 20th century, mainly because of habitat destruction, entanglement with monofilament gillnets and predation by the introduced blotched snakehead. Also, the few remaining birds increasingly hybridized with little grebes; as the species differed in several key aspects, the hybrid birds may have suffered from decreased fitness, to the detriment of the rufolavatus gene pool.The Madagascar pochard, which also lived on Lake Alaotra, was thought to be extinct but was rediscovered in 2006. Unlike this species, however, the grebe had poor powers of dispersal and was never found elsewhere.
The last sighting was in 1985 and the species was declared extinct in 2010. Only one photograph of the species is known to exist. Although some species have been classified as extinct and later have been found to still exist, Leon Bennun, the director of the conservation organization BirdLife International has stated that "no hope remains for this species" and blames the "unforeseen consequences" of human action.
This extinction brought the number of confirmed bird extinctions since 1600 AD to 162. The previous declaration of a bird species as extinct was that of the Liverpool pigeon in 2008. However, that was more a problem of taxonomic recognition as that species was last recorded alive in the late 18th or early 19th century.