The lemmings cycle: how to stop those f*ckers from constantly killing themselves?

First of all, great game! Best strategy game of this genre I've played.

I have a problem though. I built my town pretty close to a raider camp, thinking I would just wall them out. Guess again. One guy passed the place, got himself killed, then... see picture. They constantly try to bury the ones that die there, only to get killed themselves. Thus, the cycle repeats itself into oblivion.

I can only think of one solution, and that's to build a box around them. But that's a pretty f*cking huge area to cover and I'd rather find a better solution.

Any advice to a desperate man trying to find the will to keep those dumb lemmings alive?

https://preview.redd.it/l1ku3xgjrb3c1.png?width=857&format=png&auto=webp&s=f056160ab278bb1390d9476a29dd63584c53f539