I was always curious as to why "thumpers" work. Was it the sound? vibration? Were they just curious? Did it startle the shad and incite bites?

This audio finally explains it to me. It is the sound striper make when they are feeding. No wonder it works.
It's only a short audio, and it takes a few seconds to start. Check it out. It's fairly faint, so you might have to turn up audio.

Sounds Summary - Morone saxatilis

http://www.fishbase.org/physiology/FishSoundsSummary.php?autoctr=40





Have fun out there!

Thank you so much! Someone posted this many years ago and I been trying to google it the since last year but no luck. Now I know...to google for "sounds Morone saxatilis" doh! I saved the mp3 file now. Very educational. Thanks again!!!

it works,..

lol
You bet!
I did a bunch of research and combing through forums to find it.
Plano Keith mentioned that several of the RHSA have the mechanical/electric versions to free your hands and everyone loves them.

I've always figured they thought it was a bunch of pelicans and comorrants feeding on shad. Sounds logical to me.

PlanoKeith is fluffing. Thumping don't work!

Thanks for posting this audio. I've been told by divers they had seen and heard this at Texoma.
Everyone asks me why thumping works and this has always been my answer since the divers told me about it.
Do y'all think the shad school up at the thumping because there is safety in numbers? You would think they would scatter and try to get away from it.

Ok, so as a newcomer to thumping, should the cadence be slow like the audio above, or more rapid? Most of what I have seen on YouTube videos has been at about 2-3 beats per second(at least by my estimate). Will those of you with more experience please chime in?

They run for their live scatter, Jeff. Seen in many times on the graph on diff lakes too.

60 beats to 180 beats per minute. Seen them all work. Don't wear yourself out

^^^^This. Some thump faster but it isn't necessary and will tire your arm out sooner if you don't have a mechnical thumper.

I usually look for small bait balls scattered in an area before I stop to thump and fish. I've see more often the shad will school under my boat when I start thumping then rise in the water column under the boat before the fish show up. Then they scatter and regroup under the boat for hours when the fish start feeding. I think I have a video or screen shot where fish busted through a school of shad. Then the shad regrouped almost immediately on the sonar. If you stop thumping the shad and fish usually disappear. I've seen shad visually on the surface frantically going every direction with fish chasing them. That is common in the spring and summer.

Sure glad I have the electric/mechanical thumper I made. Free up my other hand to enjoy the fishing. Comes in very handy.

Cool!
You can also get one here if you're interested. Jeff from PK also makes & sells them.

http://texasfishingforum.com/forums/ubbthreads.php/topics/11389751/Bobo's_Thumper#Post11389751

We normally have an old rock station on the radio, so I wind up thumping with the beat. My wife swears they like van halen, and CCR best. That is not very scientific, but works for us.