"I weep for you," the Walrus said:
"I deeply sympathize."
With sobs and tears he sorted out
Those of the largest size,
Holding his pocket-handkerchief
Before his streaming eyes.
"O Oysters," said the Carpenter,
"You've had a pleasant run!
Shall we be trotting home again?'
But answer came there none--
And this was scarcely odd, because
They'd eaten every one."
Alice in Wonderland "the Walrus and the carpenter"
The Oysters I get usually have been frozen and thawed, so I think they are dead.... but the ones plucked out of the sea and cracked open while fresh are alive....until they are devoured by Inger.
https://www.youtube.com/watch?v=GYYfhL8PKak, They go catatonic and seem dead after opening, but you can use lemon juice to test if they are still alive.