Jorg Mazur contacted the Otago Daily Times after a whale washed up near Taieri Mouth earlier this month, making headlines around the world.
The Department of Conservation (Doc) reported the discovery of a 5m-long specimen believed to be a male spade-toothed whale — an all but unknown species of beaked whale.
"Almost nothing is known about the species, including how many of the whales exist, what they eat and how they behave," The New York Times reported.
Mr Mazur wrote to the ODT from Germany this week after hearing the news on the radio.
"Despite half the planet between us, I hope you can help me," Mr Mazur said.
He was seeking photographs or video of the whale.
Fourteen years ago, he released a print showing 21 illustrations of all the different species of beaked whales that were known at the time.
The spade-toothed whale, Mesoplodon traversii, was the only one he could not fully illustrate.
The poster includes the species, but it is represented only as a skeleton.At the time, it had only been described after three skulls and a few bones had been found after they washed ashore over the past 135 years.
Mr Mazur said he was hopeful photographs and video of the discovery at Taieri Mouth could help him complete the series.
He also bought a house on the Portuguese island of Faial, known as one of the best places in the world for whale watching.
Doc has said it would work in partnership with Te Rūnanga ō Ōtākou on determining the next steps after the discovery.
At this stage Doc could only supply the photograph it had released when news of the discovery broke.
The photo has accompanied headlines around the world.
Doc has also supplied Mr Mazur with a video taken by Mr Cassidy, which Mr Mazur said was an "absolutely fantastic" start.
