I'm new to UB and a deep water angler for 50 yrs. I like to promote deep water techniques and will periodically post some ideas and tactics. Feel free to comment, ask questions or PM. All I ask is that you try a technique for yourself before you bash it.
One of the truisms that anglers accept is that you cannot catch bass below the thermocline. The truth is they do live below the thermocline and you CAN catch them. The key to deep water fishing, especially very deep, is locating bait schools at depth. If you locate bait schools below the temp gradient, bass may well be with them. IF THERE IS ENOUGH OXYGEN FOR SHAD AND OTHER BAITFISH, THERE IS ENOUGH OXYGEN TO SUPPORT BASS.
The best way to fish for very deep bass is vertical jigging. The deep bass feed sporadically on the school. If you fish for 20 min. without a bite, move on and come back later. Dale Hollow is an example where smallmouth will bite at depth or come up for a lure. Table Rock. Norfork and Lake of the Ozarks are other lakes where fishing very deep for largemouth is possible. To help you detect strikes I suggest you use braided line. By the way, this is not a tactic for tournament fishing unless you need a kicker bass. It does tend to catch large bass. If you try it, let us know how do.
if you do have a true thermocline the dissolved O2 level is much lower than at the thermocline. this is why you see the majority of the fish population all at one level. if there is any variance to that, it is normally shallower as that water typically still contains better O2 levels than below the thermocline. fish you do see below the thermocline tend to be more at rest than active. this is also due to the lack of O2 to be active. also, the water temp below the thermocline declines very rapidly. fish being cold blooded naturally will be active for a much shorter duration because of dissolved O2 levels, and being in a colder environment. with all that said, YEP you can occassionaly catch a whopper or two below the thermocline. you do have to be persistent and keep checking on them to catch them in that brief active period.
bo
Merc, you're correct that the bass are sluggish but so are the baitfish. The bass that inhabit this depth tend to be large and are there to feed on the bait. Remember, these are basically unpressured bass and the more pressure on a fishery, the better this pattern becomes. When I take my Puma from the slip, the first thing I do is look at the electronics for the current activity level of the lake. Before I hit the no wake buoy, I know the depth I will start fishing. I will only go to the deep patterns when normal tactics aren't working or my electronics tells me the deeper bite is on.
Quote from: merc1997 on August 30, 2013, 02:54:26 PM
if you do have a true thermocline the dissolved O2 level is much lower than at the thermocline.
bo
not necessarily. however in most eutrophic lakes (highly fertile) the O2 levels below the thermocline are usually greatly depleted.
Deeper lakes like Table Rock can see oxygen at sustainable levels (fish perspective)
One other thing that most folks don't talk about, it's possible to have MULTIPLE thermoclines if the lake is deep enough
http://www.greatlakeswrecks.info/articles_pdfs/guide_to_thermoclines.pdf (http://www.greatlakeswrecks.info/articles_pdfs/guide_to_thermoclines.pdf)
Quote from: coldfront on September 03, 2013, 03:05:27 PM
not necessarily. however in most eutrophic lakes (highly fertile) the O2 levels below the thermocline are usually greatly depleted.
Deeper lakes like Table Rock can see oxygen at sustainable levels (fish perspective)
One other thing that most folks don't talk about, it's possible to have MULTIPLE thermoclines if the lake is deep enough
http://www.greatlakeswrecks.info/articles_pdfs/guide_to_thermoclines.pdf (http://www.greatlakeswrecks.info/articles_pdfs/guide_to_thermoclines.pdf)
once in a while we will have two thermoclines on table rock. this usually happens when they have really been pulling a lot of water throught the lake. running lots of water through can also just completely wipe out the thermocline, which is what happened with all the rain and high water we have had. last night in the dama area, i noticed a thermocline starting to form around 20ft. deep.
bo
Thanks for the interest in the topic. I have used this tactic since the mid-1950's starting on Norfork and the Rock. When I made LOZ my home lake I found the pattern works even better because of all the cruiser traffic. I use 8-12 in. hand poured grubs(kalin's style) on 1/2-3/4 oz. long shank ballhead jigs. 6 or 7(0) hooks work best. Look for striper jigs as a guide. The large grubs really attract the larger bass as they fall through the shad school. The bass are looking for a big lazy meal. My best morning at LOZ: first 9 bass caught all over 4 lbs.
Wizard,
I fish deep, clear East Tennessee reservoirs and am researching deep water summer bass.
There are some things I don't yet understand...
Light only penetrates so far down the water column. Where the light does penetrate, there is plankton and zooplankton (food). This, I would think, would limit the depth of baitfish. However, bass and baitfish can be much deeper than this. Can you or anyone provide "light" on this? What are the baitfish feeding on way down there below the thermocline?
east10: it's possible those baitfish are moving 'up/down' to feed as well.
the other issue, there's a 'migration' from the sediments up the water column at night as 'benthic organisms' like chironomid larvae do their 'diurnal' migrations.
Lots of things happening out there that we don't see very well.
Quit thinking of the lake as a fresh water lake. In the ocean, there are predator fish and prey living at 3000 ft. Those fish still use oxygen, reduced as it is, with no ill effects. The forage is eating deceased vegetation and small organisms. Fresh water lakes have the same thing. If the oxygen level drops too far, the fish move upwards. In all instances of a bass being deep, there has to be prey there or close nearby.
Quote from: Wizard on June 19, 2017, 01:49:15 PM
Quit thinking of the lake as a fresh water lake. In the ocean, there are predator fish and prey living at 3000 ft. Those fish still use oxygen, reduced as it is, with no ill effects. The forage is eating deceased vegetation and small organisms. Fresh water lakes have the same thing. If the oxygen level drops too far, the fish move upwards. In all instances of a bass being deep, there has to be prey there or close nearby.
now, the question we've all been waiting to ask: Wizard, do you fish below the thermocline without seeing predator fish on your sonar? (not just prey species)
NO!! Everything changes from lake to lake. I fished a tournament on Lake Mead. Sheer wall bluffs. The bass were only on the walls with shade. I caught bass from 75-113 ft. along the shady walls. That is also the deepest bass I have caught. Make sure you have something to fizz the bass. I use a small hypodermic needle.
Years ago Aaron Martens won a tournament on lake Oriville in N. Cal. He caught all his bass in 90-110 feet of water. It was mid summer and it wasn't uncommon to catch bass as deep as 60-70.
His theory was that these larger bass were hanging out deep waiting on night fall. Not that they would feed at all during the day. However he proved if you got a bait close to them and didn't rush it, the bass wouldn't pass up the easy meal. He also believed that the summer boat traffic killed microscopic life and waves, lake currents, and various factors allowed these dead organisms to fall very deep and. Air would stay deep. So the bass he was catch only moved up to 40-50 ft to feed at night.
He believed, and he was right, that every bass he came across hadn't seen a bait in quit some time and they were easier to catch. He said he might scan for an hour before making a cast but that bass once found was a sure thing.
another thing is that you can take bass seeing your line out of the equation at that depth. if that makes a difference anyway.
bo
Quote from: merc1997 on June 22, 2017, 10:26:06 AM
another thing is that you can take bass seeing your line out of the equation at that depth. if that makes a difference anyway.
bo
Kind of depends on if you believe fish have the ability to see in the UV spectrum. UV light is believed to penetrate much deeper than other types of light.
I am not much of believer in fish being wary of visible line, but it's just what I believe.
me either. i use a fluorescent line day or night.
bo
Here are the water column profiles of 2 different lakes in my area. The first column is depth, the second temperature and the third dissolved oxygen. The measurements were taken near the dam on both lakes.
Can fish live below the thermocline? It all depends on the lake.
My files were to large on the above post....
Compare this chart to the last chart posted. These are two different lakes in the same area (East Tennessee). One lake can support bass below the thermocline, the other cannot.
I tried posting all three charts in the same post, but could not (I'm new to this forum)
East10eC, thank you for an excellent post. I ask that you send your charts to Mike Cork, the owner of UB. He may decide to pin them to this forum.
Wizard
It may be a couple of days, but I will send the info (really busy with work at work and work at home)
I sincerely appreciate the information you provide.