The 3m seal, believed to have weighed more than 200kg, was lifted from Waikouaiti Beach by eight people last November and transported to the Otago Museum in Dunedin, where it was preserved in a freezer.
The seal, which usually lived near the Antarctic before venturing into warmer Otago waters, has since been painstakingly preserved by a Christchurch taxidermist, funded by a $12,000 grant from the Dr Marjorie Barclay Trust.
The sea creature will soon take pride of place in "Otago's Ocean", an exhibition being developed at the museum's Nature Galleries.
A close encounter between the seal and a short-tail stingray might well have contributed to its death.
Short-tailed stingrays are one of the world's largest stingray species, weighing up to 350kg, with a body width across the wings of up to 2m, and overall length up to about 4m.
Museum natural science research and interpretation co-ordinator Lucy Rowe said she had been surprised to learn from the taxidermist that the seal had been injured by a stingray.
During taxidermy, an 8cm-long barb from the stingray's tail was removed from the seal's head, having penetrated near the left eye and entered its mouth.
Pneumonia was the likely main cause of death, but the extremely painful barb may also have contributed, she said.
Stingray venom can cause internal organs to necrotise.
Australian "crocodile hunter' and environmentalist Steve Irwin died from a barb through the heart from a short-tail stingray in September, 2006.
A 36-year-old Canadian tourist needed surgery to his thigh in January this year after standing on a stingray near Waitara, Taranaki.
University of Otago zoologist associate prof Liz Slooten said stingrays lash out if threatened. One or two New Zealanders were injured by them annually.
