Dolphins hitting boats?

[West Coast]

On route north from Brittany a couple of weeks ago, we were on passage from Brest to the Scillies heading for the Chenal du Four. We were sailing, and had just turned North round the Pointe de St Mathieu when we were met by a large number of dolphins - some fairly large approx 6 '- 7' long. They were swimming and jumping around the boat as you might expect.

However we began to notice that some of them were deliberately bumping the boat below the waterline, you could feel and hear the bumps. Initially I thought this must have been a coincidence, perhaps the hull coming up against something else, but the bumping became more persistent as the dolphin numbers grew. This got to the point where there were 5 significant bumps over a period of a few seconds. I dont know where they were bumping the hull or keel, but it did not seem to be the rudder. After around 40 mins or so, the dolphins began to disappear.

I am aware of the Orca attacks etc happening further south, but while I was becoming concerned, I did not sense this was an attack. as such.

Has anyone else experienced anything like this?

 

[AngusMcDoon]

Yes, coming out of Padstow. I reported it to the British Association of Dolphin Botherers (may have remembered their name incorrectly there) and they said that it was rare but not unknown. After 20 minutes they got bored, or headaches, and went off for some paracetamol and mither some porpoises instead.

 

[[70521]]

Yes. Just off Plymouth breakwater we were heading straight towards it in order to pick up the 10 m contour when there was a loud bang and a dolphin at the transom. We concluded that it was warning us of the danger.

 

[luke collins]

Are any of you guys running a fish finder or Ultrasonic antifoul? Perhaps they are learning from the Orca?

 

[West Coast]

Are any of you guys running a fish finder or Ultrasonic antifoul? Perhaps they are learning from the Orca?

No, nothing like that, just ordinary (SIMRAD) depth sounder, nothing else. Engine off

 

[AngusMcDoon]

Are any of you guys running a fish finder or Ultrasonic antifoul? Perhaps they are learning from the Orca?

No, but I did have Big Hel on board who resembled a whale, so maybe it was her who set them off.

 

[[70521]]

Are any of you guys running a fish finder or Ultrasonic antifoul? Perhaps they are learning from the Orca?

My experience was a about 10 years ago so well before the current orca incidents. Just an ordinary depth sounder.

 

[neil_s]

Sailing a 13 foot dinghy along the coast some way offshore, I encountered a pod of dolphins. They wanted to play. Three would swim off ahead and come back three abreast and the middle one had to scrape past the centre board. They did this several times - no animosity intended. I don't know if I was expected to give way sometimes!

 

[oldharry]

ordinary echo sounders run at 150 - 200khz, so as these guys seem to communicate in ultrasound, could it be that our sounders are like a car alarm or worse to them. I too was 'bumped' by one off Cardigan Island in the 1970's

 

[UK-WOOZY]

got me thinking is a depth sounder needed in open ocean

 

[blush2]

Dolphins seemed to like Blush, they would abandon other boats they were following when we came along. They used to play chicken by swimming along one side from astern then diving under the bows, coming up the other side, swimming round the stern and starting over again. Occasionally there was a bump when they misjudged when to dive but it was never deliberate.

 

[colind3782]

I had that sailing around the Gib Straits. They would follow and play but a few would headbutt the bow regularly. No attempt at the rudder fortunately. Someone suggested that they were clearing the barnacles from their snout but no idea how true that is.

 

[[3889]]

Are any of you guys running a fish finder or Ultrasonic antifoul? Perhaps they are learning from the Orca?

Orca predate on common dolphin, they don't educate them outside of Disney.

 

[West Coast]

got me thinking is a depth sounder needed in open ocean

Probably not, but we were navigating a relatively shallow channel, depth around 12M or so

 

[Mister E]

I was told that Dolphins bump and rub against boats to get rid of parasites and other stuff.
I don't know if it is trus or not.

 

[Iliade]

Best keep our hulls clear of barnacles then...

 

[Dipper]

Some 25 years ago a small pod of dolphins took up residence in Portland Harbour and seemed to like following my boat. One of them enjoyed swimming upside down whilst bashing my rudder with its body which became a little alarming. A few years later the welds on my rudder tangs failed which may have been a coincidence.