Hi All,
I recently saw a hedgehog scurrying down the wall of our property towards the boundary at dusk. I went to check it out and it stayed still for long enough for me to identify that it had a patch of maybe two dozen blood sucking ticks on it’s back. 
I checked online and sources suggested this was probably an okay amount if the hog didn’t look unwell. I didn’t want to interfere with it for fear of causing it harm or removing them incorrectly (I have never dealt with a tick before).
I hadn’t seen it again since and so thought it was a one off.
Today, during lunch I went into the garden and was hearing hissing noises coming from nearby. I investigated and lifted the guinea pig hutch to find a green grass nest underneath with what I believe to be a hedgehog in the middle. There was also an area to the side with several hig looking stools. I took a photo and then retreated.

I’m concerned about the ticks and the guinea pigs so I have purchased some DE to ‘spray’ around the guinea pig cage and the surrounding grass area so try and kill the ticks as they drop off. I am informed that it is harmless to the hog, the pigs and my pet cats.
I am also concerned about the cats getting to the nest as it is accessible to them.
Are there any suggestions on how to proceed here?