The 3 kittens that I took from their mother were six weeks old and they were all traumatized from the separation from their mother. They meowed loudly for their mother and refused to eat. The mother cat was also under stress at the animal clinic. She was pacing in the crate, charging the crate, and hissing. The feral queen cat was under great stress from the separation of her kittens.
Every spring my husband and I watch for queen cats that may be pregnant. We document them by taking a photograph and we make note of their daily activities.
We will hike into the woods to make note of thicket den or hallow tree where the queen will give birth to the kittens. When a queen cat is noted we immediately set up a feeding station. By doing this we are bonding with the cat.
If there is a problem and the kittens need to be trapped then we will rescue the orphaned kittens. Otherwise we will wait until they are weaned at approximately 7 to 12 weeks old before trapping them for spay, neuter, worming and shots and socialization.