A bronze sculpture of an eel curling on its base was stolen overnight from Auckland Botanic Gardens in Manurewa.
Garden staff found this morning the sculpture, which is called "Tuna" or eel in Maori, had been sawn off from its base at its site about 50 metres from the SouthernMotorway boundary fence.
Gardens manager Jack Hobbs said thieves appeared to have targeted the work overnight.
"The bolts were sawn clean-through, leaving the mounting plate and the spiral carved base," he said.
A work by Canterbury artist Bing Dawe, the spiralling long-fin tuna was a symbol of the species "downward spiral to extinction" because of draining of swamps for agriculture.
It was such a popular item in the last Sculpture in the Gardens event if November 2013-February 2014 that it was bought for $30,000 by the Friends of Auckland Botanic Gardens for permanent exhibition.
"This is sickening," said Friends president Bill Burrill. "This stunning piece belongs in the gardens and to the people of Auckland.
"It is expertly crafted and had a perfect home in the Threatened Native Plants Garden."