make critters immune to miasma damage

[Frank_Stein]

I dunno I kind of like that cats chase mice.

Weird idea but what if station conditions determined critter spawns?

Lots of food left out: Mice, Raccoons
Lots of bodies rotting: Roaches
A lot of Bees: Wasps

You could even have players choose a spawn critter from list of available critters based on station conditions, with respawn rates adjusted to the conditions.

Lots of dead bodies, fast respawn time for roaches