The alaotra grebe, which is also known as a Delacour's little grebe or a rusty grebe, was declared extinct in 2010, although it might have been extinct years earlier. Scientists were hesitant to write the small bird off too soon because it lived in Lake Alaotra, which is located in a remote part of Madagascar. Thorough surveys of the area in 1989, 2004 and 2009 failed to find any evidence of the species, and the last confirmed sighting of the bird was in 1982.
The alaotra grebe population began to decline in the 20th century because of habitat destruction and because the few remaining birds started mating with little grebes, creating a hybrid species. Considering the bird's restricted range and lack of mobility, scientists declared it extinct, and today, only one photograph exists of an alotra grebe in the wild.
Editor's note: This slideshow has been updated since it was originally published in January 2011.