Cabbage eating Pest

Can anyone identify what is eating these cabbage leaves. Very rapid nibbling it is too! The ground has been Nemaslugged to diminish slugs. Thought it might be the cabbage white butterfly problem but there are no eggs on the leaves and no caterpillars for identification. Thanks.

 

Pigeon(s). The leaves have been torn rather than nibbled by small catterpillar mouths. A rabbit would have eaten bigger chunks/whole leaves.

 

Does look like caterpillars, but I think you need to go out after dark with a torch, could be snails.

 

I'm handicapped so I can't get into the garden at night, but there are no slime trails anywhere. However, there are several wood pigeons around. I'll keep an eye out to see if our feathered friemds are abusing their garden privileges. Thanks a lot for the advice.