Oppp's! Photo taken with my iPhone LOL x

Ants won't stay in a damp environment, so, unless you've actually seen them, they're unlikely to be the culprits. More likely to be squirrels or birds.

Usually, if ants have made their nest in a pot, you see little black specks of fine soil under and around the pot, so to check, pick the pot up to see what's going on. Ants will readily make a nest in a pot if the pot is in contact with the ground, which yours appears to be, and while they don't deliberately kill the plant, nor poison it in some way, what they do do is chew through fibrous roots if they're in the way.

Watering might help, but may not destroy the nest completely, so if you're worried, lift the plant out of the pot to see. You'll know immediately if there's a nest, and if there is, leave the plant depotted in the open, but preferably not in the sun, and walk away for a while, till the frantic ant activity stops. Then soak the rootball in a large container filled with water and without a drainage hole for at least two hours, then check the rootball for any signs of any activity or eggs, then repot, this time standing the pot on pot feet or bricks or anything that creates a space beneath it and the ground. Dust the area beneath periodically with ant powder.

I lifted a large stone & there were ant eggs, I could tell by the soil it was ants, Ha! Ha! To heavy to lift out the pot to repot, I will keep giving it lots of water & hope for the best, I wondered if I put ant killer down on top it would help?
Bamboo. I will put some ant killer in the tray as you suggested :o)) x