A Hokio Beach motorcyclist was lucky that after hitting a deer at midnight he sustained few injuries, though his new bike was a write-off. The wild deer that jumped out in front of him wasn’t as lucky.
The article below mentions that wild deer can be found on roads and even beaches (my emphasis):
Wild fallow deer were more likely to be seen on New Zealand roads in autumn months like April and May. It is mating season. They are most active from sunset to midnight, and around sunrise.
They can come down from the Tararua Ranges and have been seen along the region’s beaches. Though quite small, they can weigh up to 90kg and are nice eating.
Warnings exist for motorists travelling at night to take extra care during autumn, especially motorcyclists, as deer have minimal road sense and freeze because a motorcycle headlight on high beam can blind them.
The advice is generally to sound a horn. If there is no avoiding a collision, then it is always better to hit the deer than try and run off the road and hit something like a tree, or swerve into oncoming traffic and have a head-on collision.