Only five Chatham Island black robins remained before the breeding season of 1981-82: a pair named Old Blue and Old Yellow, a second pair named Green and White, and one surviving chick from the year before, according to the Predator Free NZ Trust. The species was considered the rarest bird species on the planet at the time.

Only five Chatham Island black robins remained before the breeding season of 1981-82: a pair named Old Blue and Old Yellow, a second pair named Green and White, and one surviving…

In 1981-82, the Chatham Island black robin faced dire straits, with just five birds remaining. To combat this decline, wildlife officials implemented cross-fostering, prompting…