Their natural urges proved deadly for two dogs that went on a mating frenzy in the middle of Kamo's Three Mile Bush Rd.
Oblivious to passing traffic, the dogs were bowled by a car outside Kamo Primary School about 6am yesterday.
People who stopped, including those in the vehicle that hit the dogs, called the SPCA to say one animal was dead and the other injured.
They then delivered the dogs to the SPCA but inspector Gill Loney said both animals had died by the time they arrived.
She said they appeared to be well fed and cared for, and not strays.