Crackling hull?

[machurley22]

Re: Puzzle for Brendan

Yes it was coming through the water and was heard most clearly inside the hull. It could also be heard faintly (if there was no wind or wave noise) when standing on a nearby pontoon with metal box floats.

Dave

 

[BrendanS]

Re: Puzzle for Brendan

You don't mean dolphin sonar do you? It can be quite repetitive like a cricket, though I wouldn't call the sound particularly cricket like.

 

[machurley22]

Re: Puzzle for Brendan

No, but the mistake you're making is the opposite of the one you describe above "... and not to dismiss aquatic life as the source of background noise". The "regular" in my question was supposed to be half a clue.

Are you fed up with this yet?

Dave

 

[Rob_Webb]

Re: That\'s it!

Other suggestions that I had were:

1. Plankton hitting the hull at high speed (er... why?)
2. Small fish hitting the hull after being chased
3. Gas bubbles escaping from the seabed
4. The anti-fouling just 'doing it's job'
5. Prawns nibbling growth off the hull

But it sounds like the snapping shrimp is the culprit. So if I lay a net out I'd be having shrimp omlettes for breakfast then?

 

[BrendanS]

Re: Puzzle for Brendan

So it's not aquatic life, but a 'mechanical' sound?

Go on, tell me, I'm not going to get it

 

[BrendanS]

Re: That\'s it!

Yep! get the shrimp net out! <g>

 

[machurley22]

Re: Puzzle for Brendan

It's a seal scarer on a fish farm. Most of them seem to have one up this way. To be honest the seals don't seem to be very scared, though perhaps it's only effective at close range.

Dave

 

[BrendanS]

Re: Puzzle for Brendan

Def wouldn't have got that one. I've never heard about those before

 

[Ships_Cat]

Re: That\'s it!

Hi Rob

I am not sure if the shrimps are the only culprits or not. It is particularly noisy in Port Nelson with the sound being a continual crackle. Looking over the side of the boat there I also see small fish (like around 1 inch) sucking at the hull and have wondered if they also contribute to the symphony.

We have a metal hull of course so only a few mm between us and the fishies, but some years ago I was on a new 55 footer being fitted out in the water in Nelson and which was diagonal kauri/glass composite, so probably similar to your AC but thicker, and the noise was loud on that too.

Regards

John