Fish Farm Seal Scarers (ADD's)

ctva

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Recently we were anchored by Tanera Mor in the Summer Isles and the 9 fish farm cages in the bay were constantly putting out a very audible clicking (like a cricket) noise which was quite loud down below deck. This was the first time that we have been consciously aware of this noise pollution.

Then on Sunday night, BBC Countryfile had a very good item on the proliferating use of these Acoustic Deterrent Devices (ADD) which scare off all marine mammals who use sonar to communicate and hunt. The fish farm representative could not answer the direct questions and kept saying "we need further evidence" despite its own expert consultants confirming the deleterious effects on seals, porpoises, dolphins and whales (he forgot to mention us :rolleyes:).

If it is annoying for us in the boat, think what it is like for the marine animals.:(
 

john_morris_uk

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Fish Farming is big business in Scotland. (It's one of the big earners alongside oil, whisky and tourism)

Seal predation of the fish is a real problem and I was talking to one of the salmon farmers about it when I was examining him for his boat driving ticket. He was one of the few who have a licence to shoot seals who are predating on the salmon in the nets. If a seal gets into a net, it's very messy with thousands of pounds being lost. However, he admitted he didn't shoot many as there are several thousand seals in his area and as he said, shooting a few dozen doesn't make much difference and just upsets the tourists.

My guess is that the clicking is a device that's being trialled and that's why the local guy you spoke to wasn't able to comment too much? Presumably it has a limited range and the idea is that it just keeps the seals away.
 

cpedw

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My guess is that the clicking is a device that's being trialled and that's why the local guy you spoke to wasn't able to comment too much? Presumably it has a limited range and the idea is that it just keeps the seals away.
They are used quite widely and have been in use for several (10+ ) years. I thought they were being discontinued but I could be wrong.

As for SEPA: a fish farm manager was quoted "I called my dog Sepa, beacause it does what I tell it."
 

dunedin

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As cepdw says, these are not new or experimental but an increasingly common source of loud underwater noise pollution.
The noise travels quite a distance when heard by humans through the hull of a yacht, so must be extremely damaging to underwater mammals that communicate and/or navigate by sound.

They are pure pollution and should, like plastic waste in water, be banned. As the industry rep admitted, there are other solutions such as double netting - but noise pollution is cheaper.
 

ctva

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...My guess is that the clicking is a device that's being trialled and that's why the local guy you spoke to wasn't able to comment too much? Presumably it has a limited range and the idea is that it just keeps the seals away.
I would suggest you look at the BBC Countryfile program which had a good report on the subject. I didn’t speak to anyone. :rolleyes:
 

ctva

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As cepdw says, these are not new or experimental but an increasingly common source of loud underwater noise pollution.
The noise travels quite a distance when heard by humans through the hull of a yacht, so must be extremely damaging to underwater mammals that communicate and/or navigate by sound.

They are pure pollution and should, like plastic waste in water, be banned. As the industry rep admitted, there are other solutions such as double netting - but noise pollution is cheaper.

well said.
 

Kelpie

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Just to offer a counter point (and yes, I work on a fish farm):
They are not new, and they are pretty much universal. It's possible that they have become more powerful in recent years (I've only been in the industry a bit over a year).
My understanding is that shooting a seal is a very cumbersome and bureaucratic process. You have to demonstrate that you have tried every other practical method to reduce their impacts- nets correctly tensioned, any dead fish removed daily without fail, and acoustic systems fully functional. Then you have to show evidence of sustained losses directly attributable to seal attacks. Meet all these criteria and you might be allowed to shoot one seal. Some site managers don't bother with shooting as it makes little difference.

Predator netting outside of the cages sounds like a good idea, but nothing in life is ever that simple. I've heard of these nets entangling seals and machinery. They very quickly before fouled with weed growth, diminishing the water quality inside the pens. And it's very difficult to seal up the bottom edge where the net meets the seabed. You have to account for tidal range and the wear and tear from contact with the ground.

As to the effects of the ADDs, I have only anecdotal evidence but the only dolphin superpod I have ever seen had two fish farms within five miles.

Personally I think the way forward is better tensioned nets, and a more active/responsive acoustic deterrent.
 

john_morris_uk

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I would suggest you look at the BBC Countryfile program which had a good report on the subject. I didn’t speak to anyone. :rolleyes:

I haven’t seen the program but it appears the company I was employed by didn’t use them. I worked for them over several years either training or examining their support boat crews and skippers and visited several sites in various parts of Scotland. (Near Oban and Mull, Shetland and Orkney) I often talked about the problems they faced in their work, including predation by seals and the various diseases they were trying to manage within the farmed salmon. I never heard the device or heard of them using it or discussing it so my apologies for my ignorance and the assumptions I’d made about it being new.

The anti fish farm lobby is very strong and loud and vociferous in some areas (and also sometimes very misinformed) but if these devices really are bad for the environment, then no doubt the authorities will be lobbied appropriately.
 

KAM

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Just come into Lamlash for the first time in ages. I can hear two seperate seal scarers. It's so loud verging on painful coming through the hull I don't think I'll be able to stay the night. The farms at least 2 miles away. It's supposed to be a marine protected area. I've phoned the fish farm operator to complain. It will be interesting to see if they respond.
 

JumbleDuck

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Just come into Lamlash for the first time in ages. I can hear two seperate seal scarers. It's so loud verging on painful coming through the hull I don't think I'll be able to stay the night. The farms at least 2 miles away. It's supposed to be a marine protected area. I've phoned the fish farm operator to complain. It will be interesting to see if they respond.
I posted about the noise off the Holy Island slipway earlier in the summer. Others confirmed it. At the time I thought it must me acoustic antifouling for the jetty because I could not believe that the fish farms would use such a volume.

Another reason to detest the damn things.
 

KAM

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I think it sounds like a fish farm I've heard it in many other locations but this is so loud it's painfull. Going to have to move on.
 

Daydream believer

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I used to watch the Berwick salmon fishers shoot seal with a shotgun off the shad by Berwick pier when the seals followed the large shoals of salmon into the mouth of the river & shoal up under the bridges waiting for the tide to travel up stream.
The seals used to take a single bite out of the middle & the rest of the salmon was wasted, because there were so many fish for the seals to just grab at will
No one complained then.
My mother tells me that "Puffy Duntas" were a problem as well, but no one can recall that far back to tell me what a "puffy dunta " was.
Does any one from "up north" recall the term?
 

MM5AHO

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I encountered about 4-5 of these during August sailing on west coast Scotland.
In Lamlash I anchored about 0.5mile off where I knew from last year that there was one. Someone anchored between me and it and later I discovered the reason they moved. They'd not known what it was, searched through their boat and then just moved elsewhere.
In upper Loch Ailort, I anchored the opposite side of the bay from a fish farm, and sure enough there was another, audible enough to keep some people awake at night, and 0.5M distant.
In the Corran Narrows one year, we anchored and suffered this noise all night. Too tired to bother shifting, we should have as a disturbed sleep isn't much rest.
They are of varying volume, and varying sound. Some sound like a 1980s dialup modem, other sound a bit like the noise crustaceans make, scratching, but with added whistles and squeaks.
I see them as a menace. To make that much noise in air, you'd probably need a permit. But to hear a submarine noise you need a boat!
 

FlyingGoose

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Just come into Lamlash for the first time in ages. I can hear two seperate seal scarers. It's so loud verging on painful coming through the hull I don't think I'll be able to stay the night. The farms at least 2 miles away. It's supposed to be a marine protected area. I've phoned the fish farm operator to complain. It will be interesting to see if they respond.
Only the northern part off lamlash bay is protected
As kelpie says the shooting of seals is the last the resort and a fish farm needs to demonstrate they have tried other measures
Acoustic sound ? With all respect to boaters here (including myself) , we all emit acoustic sound via our engines , depth sounders , fish finders etc, pointing the fingers at fish farms and trying to be holy, do not wash.
Fish farms are a huge business in Scotland and a balance needs to be made between economy and wildlife, it is a hard battle and is constantly adapting
Seal populations in Scotland are pretty stable so no real detrimental effects on their population due to fish farms
SEPA yup a government environment agency that no one really knows anything about but we like to slacg them off for not dong their Jobs , like al governmental depts. under funded , to many managers and red tape. I know I know know , but my Wife worked for SEPA during her PHD who funded it and she had access for 4 years to the dark side.
I moor at Ardrossan so Lamlash Bay is my backyard and have to say I have never encountered any hull vibrations or acoustic sounds the many times there, but i can sleep through a gale
 
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