A dog has died after drinking from the Tukituki River.
Marley was a beloved family pet and owner Chelsea Ellmers says it feels like a piece of her family is missing.
The 4-year-old labrador died due to a suspected case of cyanobacterial poisoning.
The death has prompted renewed warnings from Hawke's Bay Regional Council and the Hawke's Bay District Health Board about the risks of toxic algae in summer.
HBRC staff were told the dog was at Tukituki River's Horseshoe Bend off Kahuranaki Rd.
"Marley was as happy as can be on Saturday morning and was so excited to hop in my partner's truck and go for their weekly run and swim at the river," Miss Ellmers said.
She said her partner thought for a change that they would go to Horseshoe Bend because they had heard of a few great swimming spots. They were gone for about three hours.
When they returned, Marley looked exhausted and "just a little off". The family thought little of it and let him rest while they ate dinner.
When they returned Marley had badly deteriorated.
"I contacted the after-hours vet and arranged to meet him in 20 minutes. It took five of us to carry Marley into my car and in the middle of that he went stiff and had a seizure. It broke my heart," Miss Ellmers said.
Marley's breathing had slowed right down and by the time they got to the vet he passed in a "matter of minutes".
Miss Ellmers said Marley was a great family dog, protector and best friend to her two young children.
Stuart Badger of Hawke's Bay Vet Services in Hastings warns that dogs are susceptible to the toxins compared with other stock.
"When you go near a river, take fresh water and a bowl so you can give your dog a good drink of water before they run around, so they are less tempted to drink from the river," he said.
HBRC interim chief executive Liz Lambert said they were saddened to hear of the death of the dog.
She said the death was a sad consequence of the warm summer weather when there is always a high likelihood of algal blooms in Hawke's Bay rivers.
"We want to avoid having any more pets suffer," she said.
She said that in the height of summer, toxic blue-green algae "mats" dry out at the side of rivers as the water flows reduced.
"These should not be touched, and people should avoid swimming where mats are present." Miss Ellmers said she spoke to the council yesterday morning.
"They were very sympathetic and will be doing testing on the water but I am quite frustrated that there was no hazard or warnings in place." She said she wants warnings put in place and regular water testing so we know they are safe for not only pets but children too.
"I would hate for any other family to go through what we are going through.
Marley will be dearly missed, it's not the best start to the new year."