Sounders and Fish

[Mindi]

Do sounders scare fish....if I drift over fish in shallow water particularly I try to remember to hit the off button...but dont really know whether it matters. I am sure everyone has an opinion but has anyone seen any convincing data..? There are lots of articles on Naval Sonar which is much higher wattage than the 600/1000 we are typically using so I doubt that the Naval Sonar vs Whales vs Dolphins debate is relevant...

Here are a couple of interesting links..

http://www.danblanton.com/viewmessage.php?id=110474

second last posting interesting on the above..?

http://www.walleyecentral.com/forums.../t-135201.html

[nigelr]

Yeah Mindi, I sure turn mine off, whether drifying or at anchor.
However, I'm talking 20-30 metres, for 70m plus I might leave it on just to be sure my drift was accurate.
Cheers.

[Local_Guy]

sounders don't scare fish.. there are plenty more things in the sea for the fish to be scared of.

[castlemaine]

The frequencies most often used by Lowrance in our sonar are 192 - 200 kHz (kilohertz); we also make some units that use 50 kHz. Although these frequencies are in the sound spectrum, they’re inaudible to both humans and fish. (You don’t have to worry about the sonar unit spooking the fish - they can’t hear it.)

see ...

http://www.lowrance.com/en/Support/T...onar-Tutorial/

Cheers

[tunaticer]

Underwater is an incredibly noisy environment at least to our ears. I have noticed how fish tend to congregate in extra noisy locations like bridges, wharves reef areas etc. Even the flow of the tide creates volumes of noises much in excess of the wind on windy days.

I think fish are more alert and susceptible to movements in the water near them and heavy thudding sounds like dropping things in the bottom of the boat etc.

Generally the quieter areas we try and catch fish are more difficult to catch a feed from and I suspect it is because every little sound we make stands out a lot more.

Turn off the sounder in quiet locations and do not worry about it in noisy locations.

Jack.

[Mindi]

The frequencies most often used by Lowrance in our sonar are 192 - 200 kHz (kilohertz); we also make some units that use 50 kHz. Although these frequencies are in the sound spectrum, they’re inaudible to both humans and fish. (You don’t have to worry about the sonar unit spooking the fish - they can’t hear it.)

see ...

http://www.lowrance.com/en/Support/T...onar-Tutorial/

Cheers

With all due respect..."they would say that wouldnt they" as the saying goes.... I wouldnt expect the Lowrance tutorial to say anything else.

[2manylures]

With all due respect..."they would say that wouldnt they" as the saying goes.... I wouldnt expect the Lowrance tutorial to say anything else.

That makes a hell of a lot more sense than spending good money to find fish & structure etc only to turn it off when you actually have fish pictured.

[castlemaine]

With all due respect..."they would say that wouldnt they" as the saying goes.... I wouldnt expect the Lowrance tutorial to say anything else.

Car salesman : "this car was only ever driven by a nun to church and back to the convent" ... yep ... I can see where you're coming from Mindi.
I would have thought as one of the leaders in the technology, Lowrance would have more to lose by saying apparently clear untruths that could be picked off by better people than me.
I fish with my sounder on in shallow reefs and have heaps of Bream sitting under my boat in my burley trail, dolphins performing all around me without any apparent concern.
I'll continue to keep my sounder on.
No offence taken and non meant.
Cheers

[davez104]

So, just out of interest, whats the clicking noise that can be heard from many transducers if they don't produce any audible sounds? Surely that noise, whether its part of the sonar or not, would be clearly audible to fish in shallow water?

Dave.

[castlemaine]

So, just out of interest, whats the clicking noise that can be heard from many transducers if they don't produce any audible sounds? Surely that noise, whether its part of the sonar or not, would be clearly audible to fish in shallow water?

Dave.

As opposed to what I quoted Lowrance has said, I am too confused as I too can hear the the 'ticking' but is it in the audible range of fish???

[foxx510]

The ticking is probably just the sound the transducer makes as the high frequency signal is switched on and off repeatedly.

[2manylures]

If any of you have ever viewed fish behaviour on a portable camera that can be attached to downrigger bombs or merely dropped over the side then you would know sounders & even electric motors when compared to petrol motors have no obvious impact on fish.

Too many old wives tails.

Manufacturers would not make something to find fish so they could then be scared off with the same technology.

A recipe for business disaster.

[Mindi]

As opposed to what I quoted Lowrance has said, I am too confused as I too can hear the the 'ticking' but is it in the audible range of fish???

Thats the question...the clicking is the actual sonar pulse being generated by the transducer.....which sounds different underwater...but who knows what it sounds like to fish (or is even audible) or whether it has any effect on their behaviour.

[2manylures]

Thats the question...the clicking is the actual sonar pulse being generated by the transducer.....which sounds different underwater...but who knows what it sounds like to fish (or is even audible) or whether it has any effect on their behaviour.

If you left the sounder switched on you would find out.

You would even be able to see fish taking your bait which would suggest that this old wives tail is just that.

[foxx510]

Maybe over time fish will evolve and come to know instinctively that sounder tick=swim away!