Kaikoura is known for it's famous Whale Watching. And it's also home to a seal colony.
If your not so keen to go on a boat and see whales you can go either dolphin swimming or watching.
But if you don't want to catch a boat at all you can stay on the shore and hang out with the seals. =)
Activity -
Whale Watching
Dolphin swimming
seeing seals
Please see below a link that will tell you about Kaikoura's history and more on what to do there.