I wouldn't use slug pellets...For a few years we had a song thrush - we would see it picking the snails out of bushes and cracking them open ...and find the broken snail shells...I had a visiting hedgehog.... and a toad living under a paving stone...
Then one of my neighbours put blue pellets down (lots and lots of them..everywhere - his gravel had a blue tinge....)...no more song thrush, toad disappeared and so did hedgehog visits (whether they were poisoned or just there was no food left for them I don't know - although local hedgehog rescue man said you shouldn't use slug pellets!)
If neighbour is still using them now he must be more restrained ...blue tinge has gone...
I deliberately kept an area of my garden overgrown and now I have hedgehogs again! (I've seen 3 foraging together - I think a mother and almost mature hoglets)... but the Song thrush hasn't come back ...nor has toad...