This is a common situation familiar to every stalker and I suspect that we all have the same response to it, which is to freeze.
A deer will stand and stare and perhaps stamp its foot or bark when it thinks it has seen something funny.
If you then stand absolutely still until the deer’s nerves have settled again, you may resume your stalk with even more caution than before.
This illustrates the value of carrying a stick so that you have an extra ‘leg’ and therefore always have at least two in contact with the ground.
Just try freezing on only one leg when you don’t have a stick!
Time seems to pass very slowly because the deer will spot the slightest movement and curiosity will then change instantly to flight.
It also reminds me of my old maxim that in woodland stalking, if you are moving at all you are probably going too fast.
You can fool a deer’s eyes sometimes and its ears occasionally but you can never fool its nose; one little eddy of breeze and all you will hear is the thunder of departing hooves and perhaps a lot of barking in a very different tone.
Deer also have their little tricks and if it is not sure after gazing at you for a while, it may put its head down and pretend to graze.
But it is still very much on the alert and if you move too soon, it will be gone.