Old Blue

Old Blue
If Old Blue had not laid any eggs the black robin would be extinct.
THANK YOU Old Blue - what an amazing bird!
When the cross-fostering programme began in 1980, there were only two females out of the five robins left. Only one female laid fertile eggs and she was called Old Blue. She and her partner, Old Yellow, are the ancestors of every robin alive today.
Old Blue got her name from the blue identification band that Wildlife Services staff had put on her leg.
Old Blue did not start breeding successfully until she was about nine years old – that’s old for a black robin.
In 1983 she could no longer breed successfully. She was moved to South East Island so that her partner, Old Yellow, would pair with another bird. He did but unfortunately it was with his own offspring and not the less closely related female that DoC had hoped he would breed with.
Old Blue lived for over 13 years and produced more eggs than any other robin.

Reference:http://www.kcc.org.nz/birds/blackrobin/oldblue.asp