Dog owners in New Zealand are being warned to keep their pets away from the berries of the karaka tree, as they are toxic to dogs. The berries are eaten by native pigeons but contain an alkaloid called karakin, which can cause respiratory failure, neurological issues, and even death in dogs. Symptoms of poisoning can take up to 48 hours to appear and include vomiting, diarrhea, and convulsions. Owners are advised to seek early treatment from a vet if they suspect their dog has ingested the berries. Karaka berries were historically used as a food source by Māori but required a preparation process to remove the toxin.