Dog owners in Wellington are being urged to keep pets away from rivers under red alert for toxic algae, including the Hutt, Waipoua, Ruamāhanga, and Waikanae Rivers.
Warm summer conditions have caused an algae surge, which produces a neurotoxin harmful to humans and lethal to dogs if ingested.
The algae forms dark green or black mats that can detach and accumulate along riverbanks, making them particularly enticing to dogs.
Ingesting even a small amount can kill a dog, and owners should seek immediate veterinary care if symptoms like lethargy or convulsions occur.
Greater Wellington Regional Council is monitoring affected rivers weekly and advises checking the Land, Air, Water Aotearoa website for updates.