After a lot of difficulty (almost every tour every day seemed booked up), we got spaces for swimming with the dusky dolphins at 'Dolphin Encounters' in Kaikoura. The other alternative was at Akaroa with the hector dolphins. The traffic on the route to Kaikoura was pretty bad, and we reached Kaikoura just in time. After all the difficulty we had in securing a booking, we chickened out seeing the sea conditions and gave up the swimming spot(NZ$115/pp) to take a watching one (NZ$60/pp) instead.
For the swimmers, the company provided wetsuits, hoods, flippers, and snorkelling masks before briefing everyone. We were driven the short distance to the boat bay and were away in search of dolphins. Once out in the ocean, the swimmers were asked to gear up and sit on the platform at the back of the boat. When the dolphins were sighted, the captain signalled to the swimmers, and they all slipped off the platform (no fancy diving here). There were probably 15-20 swimmers in each of the two boats. The viewers then went to the front of the boat to see the dolphins.
I'm sure the swimmers had an amazing time in the short 10-15 seconds they were in the water each time (about five times in all), but the viewers had a magnificent view of the amazing dolphins. The dolphins were leaping and somersaulting in the air every second. There was no point in photographing them--unless we were incredibly lucky, all we would capture were splashes in the water. Looking down from the viewing deck when the boat was moving was great--we could see dolphins quickly swimming alongside the boat. Apparently dolphins love swimming in the pressure wave created by the boat--their kind of surfing! When two dolphins swam next to each other, apparently attached at one side, the guide told us that they were probably mating. Apparently a female dolphin that a researcher had observed mated five times, with three different males--all in the space of 2.5 minutes!
The swimmers were told to make noises through the snorkel and dive to attract the dolphins. Whether the dolphins took notice of them or not, I do not know, but it provided great amusement to the people watching from the boat. Some of the swimmers were raving about having the dolphins swim so close to them, and one of them was squeaking in excitement after seeing a huge dolphin right underneath her through the snorkel! I am glad that I opted out of swimming, because the rough, open sea and the winds would have freaked me out and spoilt the experience.
Hot chocolate and cookies made us all feel better when the swimmers came back on board and did some watching themselves for photos. But I must say it was best watching dolphins when the boat was cruising and the dolphins were out-swimming the boat, racing underneath and yet finding time to do their flips and somersaults!