Dolphins in Tryphena.

In early November 2005, a small pod of about a dozen bottlenose dolphins were observed to spend an entire day cruising back and forth within a hundred metres or so of Gooseberry Flat beach at Tryphena. One of the adult dolphins exhibited behaviour that set it apart from the others. It spent much time very close to the shore, and had some pale object around its dorsal fin. The water was calm and clear over white sand. 

As it appeared to be in trouble, a Gooseberry Flat resident whose place overlooks the bay rang to inform me of it. I grabbed my dive gear and went straight around to the beach where he and his partner were down by the waters edge with the dolphins not more than 50 metres off the southern stony end of the beach. They pointed out the dolphin in trouble. I swam straight out from the beach confident of drawing them to me. I dived down and blew a few bubbles, clapped my hands, cork-screwed, and made a few wheezy-type sounds, and sure enough several came over to see what was going on. They were bottlenose dolphins and there were a couple of young ones with them, - more likely to be young teenagers, in our parlance, than infants.

However, the dolphin with the object around the front of its dorsal fin was closer in and by itself. It stayed predominantly on the surface rather than diving out of sight. I went over towards it, and it seemed to me from its reactions, or lack of them, as if it lacked energy. I persisted in following it, trying to get nearer, as I thought that if there is any chance of getting the object off it, maybe a threat to its life could be removed. As I closed with it, other dolphins came in between the dolphin and myself at times. I kept seeing the pale object that looked something like a partially-filled plastic bladder, seemingly caught on the dorsal fin. Eventually I very briefly got to within about five metres of the dolphin’s left side, and was very surprised to glimpse briefly what looked like a large conger eel, its mouth toward me, draped around the dorsal fin. For the life of me I could not see how such a fish could get caught on the dolphins’s fin. I therefore persisted in trying to get closer. Eventually, after more encounters with others of the pod, several of whom had bits of weed draped across their dorsal fins, others occasionally leaping clear of the water, and having followed the seemingly troubled dolphin back and forth for some minutes, I got to within a couple of metres of it, whereupon the object was seen to be a dead newborn dolphin, and immediately left the adult dolphin alone. The pod was still there up until the light faded at least, and absent the following day.  Dr Ingrid Visser, New Zealand’s Orca guru, having been advised, promptly sent a paper (attached) on several other instances of the same behaviour by bottlenose dolphins, and which also included reference to many other cetacean species exhibiting the same sort of behaviour. Having also talked to one of the group of girls who were tightly surrounded and aggressively corralled by this same species of dolphin off a Northland beach as a large shark threatened them, and had described to me the (anthropocentrically-considered) loutish behaviour of bottlenose dolphins in apparently attempting to harass and seemingly force a small pod of obviously excited pilot whales ashore in Port Fitzroy Harbour, it has only served to increase my regard for their complex range of social behaviours.  

Don Armitage © 2005.