Between last night and this morning the Bath St artwork was tagged with the words "Coyote F*** U".
The graffiti was removed this morning.
Mural artist Tyler Kennedy Stent said he was glad he applied a thick layer of anti-graffiti coating.
"I went down with Roger [Knauf] the Graffiti Doctor and he was able to clean it off within about ten minutes. It came off very easily."
If the graffiti looked good he would have kept it there, he said.
"But it wasn't good."
Because it was such a high-profile mural he knew it would be a target for taggers, he said.
"So I'm pretty happy I put so much varnish on."
The graffiti was similar to that which defaced a Chorus Box in the city last month.
A video posted of the culprits committing the act seemed to show members of Dunedin punk band Coyote.
