Finding bottom type transitions

[irishwalleye]

Ok after reading Matt's article about Bull gills, the same question always comes up for me. How can I tell when (1) I am working soft/hard bottom (2) How can I tell when it changes back and forth? I am an electronics freak and this is one area I can never understand on either hard or soft water.

[Corey Bechtold]

http://www.vexilar.com/pages/support/support_tips/article_017.html

Another way would be to use an old fashoned depth-sounder. Simply drop the weight into the bottom to feel what it is. Sticky bottom is soft and harder bottom will be obvious, especially if it's rock.

Good luck,

Corey Bechtold

[fishcast]

I personally find the transition areas with a good 3 color flasher. But the only way to really know roughly what the bottom types are, is by just looking at the signal on the flasher is with practice.

It would probably easiest if you were to drill on top a known rockpile or something and keep drilling away from it. It will become fairly obvious once you have moved off the rocks and hit sand or something else because of the change in the signal. Then you can remember what to look for in different spots.

It is hard to just say exactly what the signals will look like when you are over rock, sand, or really soft bottom because it all depends on the depth of water, the cone angle of your transducer, and brand unit.

Like the Vexilar HSOforum has written you can compare the signals, with a more solid red being harder and mostly just green being softer.

But the most obvious way for me to find if it is sandy or harder like gravel or rock is to look for multiple "echos" (I believe that is a term for it) and remember the things I am writing are just with my fl-20 on the 19 degree beam but other units can use the same concept. The echo is another signal twice or over real hard bottom like rock three times the depth of your actual signal. However, over really soft bottom there will be no echo. This is because the harder the bottom the stronger the signal it returns I think.

I use a fl-20 with a dual beam, and usually use the 19 degree beam for bottom comparisons because that I am used to reading that signal cause I use a 19 degree puck ducer in the summer. With the Vexilar and the 19 degree beam if I see any part of a double echo in relatively deep water I assume it is sand or harder. If I see a strong (with mostly just red) band for the echo it is probably rock or gravel. If there is a triple echo it is definetely rock.

Hopefully, that made some sense