Galapagos giant tortoise (Chelonoidis nigra)

Auckland Zoo has four Galapagos giant tortoise (all hatched at Honolulu Zoo):

0.1 Snapper (1969)
0.1 Chippie (1970)
1.0 Smiley (1971)
1.0 Willie (1971)

The parents of these tortoises were wild caught on the island of Isabela in the 1920’s.

One offspring has been produced to date:

0.1 Pinta (30/12/2017) Smiley x Chippie

Pinta sadly died in May 2018.

Parentage of the Honolulu Zoo giants is rather mixed bunch with Western Santa Cruz Chelonoidis nigrita (porteri) and at least 2 central Isabela species C. vandenburghi and C. vicina in their original breeding group.

The US AZA/SSP considers all the Hawaiian Galapagos tortoise offsprings to be hybrid/unknowns at this point. Either an Isabela mixed species breedings or male breeder of unknown species to a Western Santa Cruz female.

I would be interested to know how Auckland Zoo got their giant tortoises tested since.