A few things,
1) What is that in your Avitar, a Monster 'gill or a hybrid?
2) Are you using a good scent?
3) Once you've seen a Big shadow, are you backing off and maybe throwing a Big jig after 5 minutes or more?
These fish are either hot and want to eat something, but something isn't perfect with the presentation or they're a little more active than neutral and your presentation is good enough to grab there interest. Either way they'll probably eat a jig with a trailer and plenty of good scent like SmellyJelly's Bass Feast or Crawdaddy if it's dropped on their door step without the delivery man around, now that you know there address.
Tight lines,
Wade