Precision Trolling Depths

[Big Water]

After season and season of seeing fish streak up AND down 20 to 40' to look at lures, I wonder what is the true benefit of knowing the exact depth your lures are running. I think that with very negative fish there may be some benefit of hitting them in the nose with your lure, but I'm not convinced being 10-15' away with your presentation makes a great deal of difference. Thoughts?

Edited January 2, 2016 by Big Water

[Gill-T]

Count me in for one who wants to know how deep my gear is running for reproducibility.  There are sometimes "hot zones" that fish are biting in that I want to match.  For example, If I pop a fish on a rigger down 20'.......I will make sure I have a dipsy and/or a leadcore out to cover the same depth away from the boat.

[Sk8man]

Big Water brings up a good point for exploration.  My first thought however is why are the fish coming to look and not hitting? It may be that something is wrong with my setup as well as the fact that they aren't "hungry". They are at least "curious" so I would be messing with the rigger (up and down, change in speed, turns etc.) or bring up or down another rigger  to see if they would hit that with a different setup on it or change in movement. I think an analogy from ice fishing is appropriate. fish will come and thoroughly examine a certain jig that has been presented repeatedly without hitting and then you immediately put down another line with a different jig and whamo. Another thing is we often assume that fish can't "see" something that is presented below them but we forget that despite their eyes being located topside they perceive movement primariiy with their lateral line structure but much of the time they may be looking skyward and seeing moving shapes or outlines and are attracted by that and then may discover some element of the presentation that is off, moving too rapidly for their liking and they are spooked by it or become disinterested. I always assume a curious fish to be positive rather than negative (such as one staying on the bottom without moving or suspended and not responding) and it is up to me to challenge them to hit   The exact depths lures are running are often more important in our own minds much of the time other than when there is a distinctly formed thermocline with fish sitting within a relatively narrow band. Take for example the fact that most folks set in terms of rounded of numbers (20 30 40 etc.) with no real rationale for that repeatability is really the most important factor as Gill T already noted. Just thinking out loud here

Edited January 2, 2016 by Sk8man

[Xxx]

I think that different fish species react to baits differently. I have yet to see a walleye streak 20ft let alone 40ft. Up or brown. Most all the guys that try to educate people, whether it's a tv show or a charter, they want those lures 5ft above the fish, that 5ft is sometimes 10ft above to 5 below this is just my experience. Nothing is 100% but it does get you in the ball park.

[justtracytrolling]

Precision depth control is crucial for some types of fishing, as in working structure or fish that don't budge let alone streak. That being said I'm the type that needs to know where all my gear is...

[Sk8man]

You know I was thinking salmon and trout totally when I made my comments and as we know walleyes are a much more "elusive" and seemingly "picky" species and I don't think anyone here or elsewhere in their right mind for that matter would argue against your trolling methods Justin- pure and simple you've got it down and it works.

[Big Water]

Thanks for the replies guys. Sk8man, I don't know what you're seeing, but I have a lot of fish streaking to look at lures and even following for extended periods. I don't think this is uncommon and if I knew the trick to force them to hit, I'd certainly use it. Changing lures, speed and direction sometimes works. If I had to wager a guess, I'd think that 15-30 fish probably follow for each one that "commits". Underwater GoPro clips probably confirm this. I guess my point is that active fish will travel from quite a distance to investigate.

Edit: I am referring to salmon and trout. With walleye and structure relating fish, I believe that proximity is critical.

Edited January 3, 2016 by Big Water

[Sk8man]

I hear ya Big Water. Anyone who thinks they have these fish totally figured out is sadly mistaken .  My gut hunch though is that in the cases of the curiosity streaks that trout and salmon come to investigate and either the terminal lure isn't what they want or were hoping for or that something in the setup  may be "off" for them (e.g. they see the line, the vibrations from the rigger wire or the attached weight spooks them, the proximity or distance of the weight/lure or the action of the lure itself looks phony or strange to them). It is also possible that they may not be hungry and are just curious about the vibrations in the water in and of itself (which I strongly suspect is a factor in the use of my coppers and leadcore). Nobody actually knows the accurate answer to this dilemma but speculation can lead  to some successful results sometimes which is why I made the above suggestions. Regardless of the reason it is as frustrating for me as it is to you

Edited January 3, 2016 by Sk8man

[Tyee II]

This is a great topic for discussion! People can come up with so many different conclusions, but the truth is you really don't know the answer because you can't really see what is happening underwater. This is exactly why I started using a camera on my rigger when conditions are right for it.

I have been filming with a Gopro on one of my riggers for 3 seasons now, and it is hard to believe how many fish follow a bait, but don't commit. I have one clip where a Laker swims up to the bait, swipes at it, falls back, then comes back and does the same thing like 13 more times. I also have clips that show fish looking at my higher outdown bait, then shooting 15 feet deeper to investigate the bait in front of the camera. The statement that fish won't, don't, or can't feed downward is a complete falacy. They can see and feel things below them and if they are interested in your bait below them, it is nothing for them to kick their tail a couple times and get beneath it to gain an advantage and get a closer look.

I used to get frustrated when I would review my footage and see so many fish looking but not striking, but I have come to the conclusion that it is when I am NOT seeing fish that I am doing something wrong. I feel that if I am drawing them close enough to film them, or see them on the graph, it's just a matter of time before I get some takers.

[Big Water]

Good responses Sk8man and Tyee II. That GoPro story is why I've never bothered with putting one down. I figured it would just frustrate me, but you make a good point that if you're at least drawing them in, you're doing something right.

[Tyee II]

Using the GoPro has been nothing but a positive experience. It has both confirmed some of the previous theories I have had, as well as creating new ones for me. Although it is tedious to review the footage, it's pretty exciting to see what was really going on down there the day before!

[Sk8man]

I just got a Hero4 Silver GoPro for Xmas and will be taking it to Yellowstone in late June to try out and I'm not sure whether the volcanic activity out there is any more dangerous than trusting my downrigger wire  for underwater shots....maybe when it isn't so new   Tyee I think you may be more of a risk taker at this point than me 

Edited January 3, 2016 by Sk8man

[Tyee II]

Ha, I'm really pretty conservative actually. I figured it wasn't much more risky than sending a $700 probe down there;)

That Hero 4 should bag you some awesome footage out at Yellowstone, that's for sure!

[fathobbit0074]

What kind of setup are you using tyee I'm interested in getting a setup

[Tyee II]

First year, I bolted the camera right to the tail of a Gander Mountain 12# weight. I just ground the eyelet on the tail(the one you would clip a release to) flat and the same thickness as the plastic mount on the camera housing. I got some great footage that way, but the footage was shakey, so I made a housing similar to the Troll Pro housing out of PVC fittings and pipe, and some SS hardware. Now I just mount the camera inside that torpedo housing (inside the waterproof GoPro housing, of course).

[pvelyk]

I have been watching this Kickstarter campaign for a downrigger camera for a real good price compared to what I paid for my GoPro.  Having been burnt by a Indiegogo project I am willing to wait for it to go to retail and grab it then if reviews are decent. For a $130 and it being built around fishing and it is nice and streamlined to prevent blowback, it looks pretty darn interesting for what you are talking about.  Plus I rather lose $130 to Lake O than $300 or $400.

 

 

 

 

 

http://gofishcam.com/productspecs/

[Tyee II]

Looks interesting. Have you seen the Waterwolf camera? I have seen some cool footage from the Waterwolf running behind a dipsey.

[pvelyk]

Interesting, gonna give it a good look.  First appearance is the Water Wolf is more setup to be on the fishing rod line which scares the heck out of me.  Probably better footage but risk is a lot higher that way.

[Gill-T]

From footage I have seen, big Kings in particular will follow and swipe at a rigger bait and turn and drift downward about 10'.  I want to know where my rigs are because I want a second chance at those fish by having at least one dipsy below my deepest rigger if possible.

[Tyee II]

From footage I have seen, big Kings in particular will follow and swipe at a rigger bait and turn and drift downward about 10'.  I want to know where my rigs are because I want a second chance at those fish by having at least one dipsy below my deepest rigger if possible.

I like the idea of having something down and behind...what do you typically run on that dipsey?

[Big Water]

I like the idea of having something down and behind...what do you typically run on that dipsey?

A MUPS rig with a fixed slider 10-15' above your main rigger line works well.  Have a 6' fixed slider and back your main line 15-25' off of the ball.

[Gill-T]

I like the idea of having something down and behind...what do you typically run on that dipsey?

 

Almost always a flasher and fly

[Tyee II]

Interesting... I wonder how a spoon would perform at the task? I used to catch a lot of fish on a Deep Six diver right down the chute, mostly with spoons though. You're making me wonder if this might be related to those fish that strike, then drop away like that.

[Smart Troll]

After season and season of seeing fish streak up AND down 20 to 40' to look at lures, I wonder what is the true benefit of knowing the exact depth your lures are running. I think that with very negative fish there may be some benefit of hitting them in the nose with your lure, but I'm not convinced being 10-15' away with your presentation makes a great deal of difference. Thoughts?

 

 

Big Water,

 

I have no doubt that fish will sometimes notice a presentation and swim up to look at it...but they might not always come from as far away as it looks on a fish finder because of how the cone area works. Please consider the attached illustration. If that fish stays at one depth and you drive the cone of the fish finder directly over the top of the fish it will look deeper when it first enters the cone than it looks at the center of the cone. That is why fish appear as arcs...they enter the edge of the cone farther from the transducer and thus look deeper. as they approach the center of the cone they look shallower and shallower. As the fish passes towards the opposite side of the cone getting farther from the transducer...it looks deeper and deeper again.

 

If the center of the transducer's cone gets directly over the fish and it starts to swim along you would not see the trailing side of the arc because the fish is swimming along with the boat and staying in the same relative position under the transducer's cone...and the fish would have appeared to streak up even though in this example the actual depth of the fish did not change. If the fish is swimming along with the boat near the edge of the cone and then speeds up so it is directly under the center of the cone it will appear to have streaked up even if its depth doesn't change because it is farther from the transducer when at the edge of the cone area and closer to the transducer when directly under the transducer.

 

The arc is most pronounced if the fish travels directly under the transducer but less pronounced if the fish is in the cone but off to the side...never directly under the transducer. The only time the fish is at the depth indicated on the fish finder is when it is directly under the transducer. All other times the fish will appear to be deeper than it actually is. The fish finder tells you the distance between the fish and the transducer.

 

 

The animation and explanation below was copied from here...The right side of the animation is showing the arc forming as the transducer passes over a fish that remains at one depth.

 

http://support.lowrance.com/system/selfservice.controller?CONFIGURATION=1001&PARTITION_ID=1&secureFlag=false&CMD=VIEW_ARTICLE&ARTICLE_ID=2967

 

Why Fish Arch

The reason fish show as an arch is because of the relationship between the fish and the cone angle of the transducer as the boat passes over the fish. As the leading edge of the cone strikes the fish, a display pixel is turned on. As the boat passes over the fish, the distance to the fish decreases. This turns each pixel on at a shallower depth on the display. When the center of the cone is directly over the fish, the first half of the arch is formed. This is also the shortest distance to the fish. Since the fish is closer to the boat, the signal is stronger and the arch is thicker. As the boat moves away from the fish, the distance increases and the pixels appear at progressively deeper depths until the cone passes the fish.

If the fish doesn't pass directly through the center of the cone, the arch won't be as well defined. Since the fish isn't in the cone very long, there aren't as many echoes to display, and the ones that do show are weaker. This is one of the reasons it's difficult to show fish arches in shallow water. The cone angle is too narrow for the signal to arch.

[Big Water]

Smart Troll thanks for the detailed explanation which will likely be beneficial to some newer guys. I'm well aware of the mechanics of fish finders and why the "arch" occurs. The situation I'm referring to is fish moving up/down 20 to 40'.