The Otago Regional Council is encouraging dog owners to be careful of their pets around waterways.

This comes after the death of a young dog, which is being linked to toxic algae poisoning.

It had been playing on the Cardrona River near Wanaka over the weekend.

The council's Dean Olsen says growth of the algae linked to the death is common during period of low river flow.

He says pets should be taken to the vet immediately if they show signs of illness after coming into contact with algal mats.