Have you ever watched a lion stalk its prey? It doesn't look like a lion. It looks like grass. That's why the prey usually doesn't figure it out until it's too late. They hear a rustle… they look over… "phew" it's just the wind. They continue doing whatever it was they were doing…
Now another one looks up. It notices the eyes in the grass. It can see the tail on the prowl…
The lion knows it's been noticed. So, what does it do? It doesn't run away. It doesn't say "oh darn, you got me… now I'll leave". No.