The first leopard seal of the season arrived in Dunedin yesterday, and it had already been put in danger before the day ended.
Department of Conservation biodiversity manager Jim Fyfe said about a dozen dog prints, some as close to 5m, surrounded the seal as it lay on Tomahawk Beach.
The juvenile seal, which he believed was a female, was about 2m long.
Fyfe was "disappointed" the endangered seal had already been harassed.
"It's disappointing and frustrating that it's still happening and dog owners don't appear to know what 20m away really looks like."