Stray dogs are a constant and dangerous threat to Daphne. They have an extremely long aggro radius, but only attacks where you are near to them. At this time, there are only two variations of stray dogs on the island. Both are rottweiler breeds that simply have different coloration.
There are no hard facts in the lore to this point as to why the Rottweiler is the only breed of stray dog currently on the island. While it could be simply the early development of the game, murals and documents found appear to paint the dogs in a happy, positive light, accompanying their families in their day-to-day activities. The Rottweiler is a herding breed that is well-suited as a guard dog, but there is no evidence supporting the need of herding dogs by the island's original inhabitants, who were fisherman.
One of these animals can be found dead in the sunflower field near the Temple Ruins. It does not appear to have been slain by the Executioner patrolling the area, as it is found with a knife protruding from its side. It is also unlikely that it was killed by soldiers during the events detailed in the Work Report - Incident document, as soldiers would have simply shot the animal. One possibility is that it was killed by one of the other survivors.
The attack patrons of the dogs are very simple, the dogs will try to evade all of Daphne's attacks and sometimes will charge against you.
According to the Breeding Report, these dogs are collected occasionally to replace dogs that were euthanized or killed in evaluation for The Trials. Given the aggressive nature of the strays, it's uncertain how these animals could be introduced to the kenneled animals in The Coastal Tower.