Lateral lines

[Louise Jenkins]

Lateral lines pick up vibrations in water.  Lateral lines cannot pick up acoustic signals.  So.……..does anybody know what the cut-off frequency for the lateral line actually is?  The barramundi in Aus has a cut-off upper response frequency of 10 hz (that's 10 cycles or second or equivalent to 10 x 60 cycles per minute = 600 rpm).

 

Electric trolling motors spin the prop at anything from 100 - 600 rpm depending on current.  So stealth mode on a electric trolling motor isn't stealth mode at all.  Its stealth accompanied by a brass band (electric propeller spinning at up to 600 rpm sending out signals for lateral line in all directions).

 

Was wondering if bass had similar lateral line characteristics?  Or can anybody point me towards somebody who might know, please?

[Bluebasser86]

I'm not sure what the cutoff is, but I know that they can detect in some form, the vibrations from trolling motor, as well as the pinging of depth finders. It doesn't always turn them off or scare them away, but they certainly can sense them. That's why most big bass specialist will go without electronics and some will even anchor instead of running a trolling motor, or make long cast at the very least. 

[Louise Jenkins]

Thanks for that.  The figure of 10 hz (600 rpm) is what scientists tell us about barramundi (lates calcarifer) lateral line operation in this part of the world.  I believe that while they can't hear the frequencies in use by the sounders (50, 83, 200, 800 khz etc), they can hear the ping of the sounder when the transducer crystal gets hit by the sounder burst of energy.  I guess that's what you're referring to.

 

The frequency of the ping rate depends on the pulse repetition freq, I guess.  Mostly that's preset automatically.

 

There may be something in what the pros say about their electronics.

 

Lateral line fishing is not a well known feature here.

 

Be interested to know about US bass though.  I reckon there's been some scientific study on it there somewhere.

[CrankFate]

Nobody knows exactly what lateral lines do or how they work in different types of fish. They are known to pick up sound, vibration, smell, taste, electricity, temperature—everything except sight. They definitely pick up electricity in all fish. But some fish are better metal detectors than others (like sharks which have additional sensors).

 

If you have large fish in a tank, and try to touch them from an angle they can’t see, they can feel it and get away before you can touch them. If you use a wooden chopstick, it’s much easier to poke them. But if you use a metal knife or fork, they feel it more than wood, but not as good as a live finger and usually get away. 

 

I am skeptical of what scientists say. I would listen to a pro fisherman’s advice on fish before a scientist.

[Team9nine]

1-80 cycles is the most frequently tossed around range for LMB lateral lines I’ve seen (peak 20-50), but some studies suggest their could be overlap between hearing and feeling in the 100-200 cycle range.

[WRB]

The lateral liners made up with pore scales with each scale having hole with a nerve ending to feel water pressure waves at very low frequency measured in CPS or Hz cycles per second.

Bass also have ears that pick up higher frequencies at closer distances.

When considering what range of frequency bass can react to consider both lateral line and hearing ability.

Look up what frequencies Hydrowave operates at, someone studied Black bass and baitfish to determine what frequency works to attract them.

I know from observation bass can react to sonar operating between 50-200 KHz.

Tom

[813basstard]

Our usual cut off is when the 10 year old starts dancing to his own beat he’s making on the side of the boat. 1/2 oz jig pitched at his leg normally gets him back on track.

[Louise Jenkins]

Can relate to cut-off point with the 10 year old.

[BassNJake]

On 5/26/2019 at 5:17 AM, Louise Jenkins said:

Be interested to know about US bass though.  I reckon there's been some scientific study on it there somewhere.

I always thought I reckon was a southern saying, just didn't know it came from that far down south!!

[Louise Jenkins]

We all learn something new every day, eh?

After all, it is northern Aus where we speak proper.

Cheers.

[Louise Jenkins]

Been thinking about lateral lines a bit more and came up with 2 further issues to explore.

 

Found some research that confirms very low frequencies (sub-audible) are the go for fish lateral lines. 

 

That threw up issue No 1 which is the range at which vibrations due to movement in the water are transmitted.  Because of the low frequency involved, range in relation to lateral lines is going to be greater than range in relation to audible sounds of higher freqs.  How much greater is the question.  Are we talking body lengths or inches?  I suspect body lengths.  Thoughts?

 

 

Issue 2 is that one of these sensors must give homing ability for the fish to find the source of the disturbance.  Somewhere along the line the fish needs to be able to find those potential food sources or to avoid a predator.

 

Because the lateral line system has 2 lines (one surface and one in canals under the scales), it must be able to sense direction.  The directional indication wouldn't need to be highly sophisticated but sufficient to put the fish "in the ballpark" to the stage where other sensors can take over for the strike (eg eyes/colour). 

 

I suspect that the existence of the 2 lateral lines means that the fish can process the differences in signals between the 2 and from that determine simple left/right direction indicators on which to "home-in".

 

I guess that I'm really working backwards in trying to understand what tools a fish has and how it uses them to get a feed and then working out a way to use the characteristics of those tools to advantage.

 

 

[RAMBLER]

Is this overthinking?  To me it's simple.  If you make ANY

 noise in the water or boat the fish hear it.  Now, whether they are accustomed to that noise and find it frightening or not is up to the fish in the specific environment it lives in.  I do know that I have found a school of crappie by fishing structure and then turned the depth finder on and the crappie left or just quit biting.

[Team9nine]

Issue 1, in regards to feeding, is about 1 body length or less. It is more for directional final adjustments, not long range/initial detection.

 

Which takes us to Issue 2: Sight and sound can both be used to initially get a basses attention and begin searching for an item, sight being the more dominant sense. Sight allows for initial analysis and setting the proper attack angles. Once an attack commences, the lateral line stimuli are utilized for final adjustments in regards to how the bass overcomes it’s prey. Bass tend to be more “ram feeders,” using their lateral line senses to decelerate and brake immediately preceding the suction feeding we often associate with bass. However, the slower the attack, the less the lateral line comes into play.

 

Of course, it is much more complicated than just this overall simple explanation.

[Choporoz]

On 5/26/2019 at 12:19 AM, Louise Jenkins said:

Electric trolling motors spin the prop at anything from 100 - 600 rpm depending on current.  So stealth mode on a electric trolling motor isn't stealth mode at all.  Its stealth accompanied by a brass band (electric propeller spinning at up to 600 rpm sending out signals for lateral line in all directions).

I've been somewhat fascinated by how trolling motors (as well as sonar and other man-made sounds) affect bass.  I never really got too far down the road, though.  Because the prop spinning at 600 rpm is only a portion of the sound/pressure the trolling motor puts out.  From cavitation to mount/boat vibration to bearing/housing noises, etc.  Hopefully, any studies would be able to narrow the variables.  How close does a jet ski have to pass in order to block those noises/pressures?  What about secondary echoes off sea walls and the bottom?   Does a 7 year old bass have same sensory range as a three year old?  I guess I usually just default to considering the subject like a few of those above: it's more important to me to have a sense what the general reaction to sound is...than to try to define the fish's sensory 'capabilities'.

     One of my more memorable learning examples:  As I was troll-transiting through a bay one morning (~4 FOW), I saw a nice LMB, maybe 3 pounds, cruising along several feet away -- she didn't have a care in the world and was paralleling my course and speed for maybe 20 yards.  As I neared the spot I was headed, I eased back on the throttle just slightly.  That fish bolted away like I hit her with a cattle prod.  Steady sound, vibration, movement...didn't bother it in the least -- almost imperceptible change and that fish was out of sight in a half second.

[WRB]

We think of the lateral line as the pore scales from behind the gill cover to the base of the tail as the only hearing sense a bass has, not true.

The latera line serves to detect water pressure waves or what we call sound that travel 5 times faster in water then air. How far away from the bass the pressure wave source is depends on a lot of factors, current being very significant. The lateral is first sense to detect pressure waves, followed by several sensors all around it's head. When anything comes within a few feet all the hearing senses are deadly accurate, the bass knows exactly where the sound is coming from and uses it's keen sense of sight to determine if  it's prey.

It's always been my belief when bass are located in what they feel is a safe zone sound doesn't alarm them to the point they bolt away. When bass are located outside their safe zone they become more wary and sound or shadows can cause them to bolt away to a safe zone.

A bass can be located under a mat in 18" of water and not move with a boat within a few feet. The bass could be away from it's safe zone in several feet of water and bolt if you approach from over 100 feet away, if it detects your presence.

We can study the anatomy of a bass to understand how it's hearing works and apply it to our fishing presentations knowing they have a keen sense of hearing and very good vision underwater.

Tom

[Deleted account]

1 hour ago, WRB said:

How far away from the bass the pressure wave source is depends on a lot of factors...

You must have watched that "The US is only 1/2 the size they tell us" YouTube video...  

[Louise Jenkins]

Thanks for those responses fellas.  Food for thought in there and I'll look further at it.

 

In northern Aus we have an iconic fish called a barramundi (lates calcarifer) and I'm a barra fishing tragic.  There seems to be a lot of misinformation around barramundi fishing so I decided to look for myself and its been quite a learning experience.  Unless you go back to basics to understand what senses that fish possess and how they use them, you have no idea on what credibility to put on what bits of information that abound.  

 

In finding out for myself, I've come across a lot of stuff that has historically been taken as gospel and that simply doesn't stack up.  Its usually presented in such a way that the claims seem to be confidently wrong rather than hesitantly correct.   Presented in such a convincing way, its difficult for people to question it without appearing to be dumb.

 

Some of the senses are common to fish world wide and some are more specialised. Lateral lines, hearing and vision are topics that I started on.  Barramundi to Aussies are what bass are to US fishers.  That's why I've ended up on the forum looking for info on how you guys work your bass out.

 

I have an engineering background and look for technical reasons for things being the way they are rather than simply the result of "black art" knowledge.

 

There'll be lots of similarities with bass/barramundi fishing along with some differences.  The senses used will be mainly common with maybe slight variations in application eg frequency response characteristics of lateral lines maybe.  I don't know 'cos I've never been bass fishing.

 

I've put together a couple of thoughts about the issues on pdf and wouldn't mind putting them up to see what you guys make of them.  Remember that we're dealing with basics about barramundi but some will line up with bass.

 

I'm happy to take on board any suggestions or observations.

 

 

 

 

[soflabasser]

A barramundi is much more similar to a snook than a bass so I will compare barramundi to snook. Both snook and barramundi are apex predators with similar ways they hunt prey. Both are fish that can live in fresh, brackish, or saltwater. Both have a highly developed lateral line so sensitive that they can locate and bite a lure on the darkest of nights. We can talk more about the science of the lateral line but what matters most is knowing that both snook and barramundi can track down a lure at night, in murky water, and other low visibility conditions. Both fish are master ambush predators so you need to know how to read structure and how these fish relate to it. 

[Louise Jenkins]

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Posted June 1

A barramundi is much more similar to a snook than a bass

 

Never seen a snook but I've heard others make that comment.  I'm looking at lateral lines as part of a "know thy enemy" project.  If I know what tools the fish has, how they work and how they're used, then my knowledge base is a bit further advanced.  The subject of lateral lines is but one of the tools.  The reason I'm doing it this way (step by step) is because there's so much mis-information out there in "barra land" (and I'm sure a similar thing exists in "bass land") that trying to work out what is what is like watching an octopus trying to make love to a set of bagpipes.

 

Instead of accepting "folklore" I'm starting from a knowledge base based solely on my experiences.  Some of those experiences don't correspond with folklore.  I guess its a case of which "expert" do I take notice of 'cos there are heaps of them out there.

 

I'm a fair way down the track with my research.  I came to this website to learn as I know you guys are big into bass and that a wealth of knowledge and experience exists here on subjects universal to fishing and not simply species related.

 

Along the way, I've picked up "the missing link" (in this part of the world) in what happens to colour underwater.  Jeez, that's caused a lot of misunderstanding here for a long, long time.

 

I'm happy to put some up on here as an attachment if anybody would like it.  Some of it relates to barramundi as THAT is the species I chase (lateral line operation, eyes, hearing, environment) but some is universal (water turbidity, colour penetration of water - " the missing link area".

 

Are you guys happy for me to put a bit of stuff on here?

[soflabasser]

It is well known that snook, nile perch, and barramundi all share a common ancestor that is one of the reasons so many people compare snook to barramundi. I like to keep things simple and effective and not worry so much about the intricacies of the lateral line. What matters most is that bass, snook, and barramundi all use the lateral line to locate prey in muddy water, low light conditions, etc. It would be better to understand how a fish moves throughout the seasons, where do they spawn, what is the best time to catch them, what are the most productive baits to use, etc. What is the biggest barramundi you caught and how many of them where over 100 centimeters in length? From my research a 100 centimeter or bigger barramundi is considered a trophy catch for many, similar to how a 40 inch or bigger snook is a trophy catch for South Florida fishermen. 

[Louise Jenkins]

I didn't know about the common ancestor.  Nile perch are a close relative but have smaller scales and they grow bigger.

 

I guess that I have an enquiring mind.  THAT'S what started me wondering why the accepted folklore had traction with many others when it didn't seem to add up for me.  Lateral lines are accepted as the prime tool in our mostly turbid waters for finding food but the lure manufacturers don't seem to pay a lot of attention to lure action. 

 

For example, I've never seen a lure that has the vibration rate stamped on it anywhere.  They have lots of colour and some are real works of art.  Rembrandt couldn't do better.  Lure colours in water are a different issue and seem to justify the oft quoted remark " lures catch more fishermen than fish".

 

I've caught a few barramundi with 95% as tag and release so keep pretty good records.

 

Last count was 3364 since 2002 with 23 over 1 metre and the biggest at 135 cm.  If laid end to end, the distance is 1787.2 metres ( 65.8 metres to make the nautical mile).

 

That's the experience that I lean on when trying to work out why a lot of the guru information doesn't add up.  That colour missing link was the clincher for me.  

 

What is the ancestor that you mentioned?

 

 

[Sam]

On ‎5‎/‎30‎/‎2019 at 2:26 PM, WRB said:

We think of the lateral line as the pore scales from behind the gill cover to the base of the tail as the only hearing sense a bass has, not true.

The latera line serves to detect water pressure waves or what we call sound that travel 5 times faster in water then air. How far away from the bass the pressure wave source is depends on a lot of factors, current being very significant. The lateral is first sense to detect pressure waves, followed by several sensors all around it's head. When anything comes within a few feet all the hearing senses are deadly accurate, the bass knows exactly where the sound is coming from and uses it's keen sense of sight to determine if  it's prey.

It's always been my belief when bass are located in what they feel is a safe zone sound doesn't alarm them to the point they bolt away. When bass are located outside their safe zone they become more wary and sound or shadows can cause them to bolt away to a safe zone.

A bass can be located under a mat in 18" of water and not move with a boat within a few feet. The bass could be away from it's safe zone in several feet of water and bolt if you approach from over 100 feet away, if it detects your presence.

We can study the anatomy of a bass to understand how it's hearing works and apply it to our fishing presentations knowing they have a keen sense of hearing and very good vision underwater.

Tom

In one of Uncle Homer's and Glen Rau's videos, Uncle Homer stated that the larger bass withdrew into their safety areas when they heard a trolling motor or motor prop.

 

Seems the larger ladies got used to knowing that they could be hooked and dragged out of the water when they heard and felt the props turning.

 

So what Tom penned above is true based on years and years of study of the largemouth bass.

 

I suggest everyone get the Bigmouth series by Uncle Homer Circle and watch them. Fascinating footage of the largemouth and its behavior that is still true today.

 

https://www.bassmaster.com/news/homer-circle-dies-97

[WRB]

Back in 1985 (34 years ago) I wrote a In-Fisherman article "A Rare Chance for a World Record Bass".  The article was about lake Isabela in central California where 7 to 8 year old FLMB were achieving phenomial 18 lb weights. My forecast didn't happen do in part to the dam being condemned and the water levels drawn down 75%, with cold snow melt spring run off lowering the pool water temps too low for FLMB to survive.

My point is I mention turning off sonar units before fishing known big bass locations and approach those areas very quietly to reduce spooking giant bass. It was common knowledge way back in the early years of using flashers bass sometimes spooked when the units were switch on.

Since The OP is from Australia I was surprised to hear from Australian bass anglers who read the In-Fisherman article inquiring mostly about custom painted big lures. I learned there was a fresh water native bass called Australian Bass a relative of American Black bass that looks similar to a Smallmouth bass and about the same size. At that time there was a program to introduce Florida strain LMB in Australia and apparently anglers were reading about the FLMB.

Off topic but ro remind US anglers that bass fishing is international with varying view points.

Tom

[soflabasser]

11 hours ago, Louise Jenkins said:

I've caught a few barramundi with 95% as tag and release so keep pretty good records.

 

Last count was 3364 since 2002 with 23 over 1 metre and the biggest at 135 cm. 

 

The current all tackle record barramundi was 135 centimeters in length and weighed 44.64 kilograms. It was caught on a swimbait that was similar to some of the swimbaits I use to catch big snook in inlets and other places with running water. How much did your 135 centimeter barramundi weighed? Would like to see a picture or video of this fish if you have it. 

11 hours ago, Louise Jenkins said:

I didn't know about the common ancestor.  Nile perch are a close relative but have smaller scales and they grow bigger.

 

Most Ichthyologist agree that snook, nile perch, and barramundi all had a common prehistoric ancestor. These fish are in the same family called Centropomidae which is why they are so similar to each other in appearance and behavior. 

[Louise Jenkins]

We don't weigh fish here just measure them. 

 

That 44.64 kg barra was caught in a freshwater lake to the south of where I live.  Fred Haigh Dam aka Lake Monduran.  Think the guy was using a kayak and got towed around a bit.  There's a big difference between lake/impoundment barramundi and wild barramundi in both weight and eating quality for fish of similar length.

 

Impoundment/lake barra have to be stocked as they need salt water to breed.  They grow fat & lazy with ample food supply and weigh heavy.  A similar sized wild barra wouldn't weigh as much as they expend more energy finding food.

 

My fish was about 30 kg or so.  No photo.  Brother released it at side of boat accidently as I was getting camera ready.

 

I've got a photo of a friend's 154cm wild barra caught in our river system (Fitzroy River Qld) that would have gone about 35-40kg.  Caught on live herring while fishing for smaller type of fish.

 

A couple of photos.  A 34kg dam barramundi which was 129cm and a wild caught 131cm on a measure mat (most measure mats only go to 120cm).  Note how fat the 34kg fish is compared with the others.  The one from Monduran Dam was a fat fish also. 

 

Barra between 85cm and 100cm are the hardest to handle.  Up to 85cm they've got agility but little bulk.  Over 100cm they've got bulk but little agility (just tow you around).  But between 85 - 100cm they have both agility and bulk and can be a real handful if there's a bit of run in the water.

 

The snook comes from a different family to barra/nile perch.  Snook family is Centropomidae while barra/NP come from the Latidae family.  Different genus and species.

 

Both barramundi and snook are hermaphrodite fish (change sex) with both having a slightly turned up lower jaw but that's where the similarity ends.   Snook with long thin bodies look like a local species called whiting.

 

We get Florida based fishermen come here to the Fitzroy to chase barra, saratoga, threadfin and permit on fly.

 

Aus's most common natural bass are cold weather fish and they also need salt water to breed but they're pretty small.  I live right on the Tropic of Capricorn (much warmer) and too far north for bass.  A 54cm one would be classed as a trophy fish here.  Mostly they're released but taste ok for a freshwater fish.