diff --git a/code/__DEFINES/mobs.dm b/code/__DEFINES/mobs.dm
index 59093a4eb95..0db55b8d376 100644
--- a/code/__DEFINES/mobs.dm
+++ b/code/__DEFINES/mobs.dm
@@ -880,3 +880,8 @@ GLOBAL_LIST_INIT(layers_to_offset, list(
 #define HEALING_TOUCH_ANYONE "healing_touch_anyone"
 #define HEALING_TOUCH_NOT_SELF "healing_touch_not_self"
 #define HEALING_TOUCH_SELF_ONLY "healing_touch_self_only"
+
+/// Default minimum body temperature mobs can exist in before taking damage
+#define NPC_DEFAULT_MIN_TEMP 250
+/// Default maximum body temperature mobs can exist in before taking damage
+#define NPC_DEFAULT_MAX_TEMP 350
diff --git a/code/controllers/subsystem/minor_mapping.dm b/code/controllers/subsystem/minor_mapping.dm
index 662bdd57528..5b2c17cf802 100644
--- a/code/controllers/subsystem/minor_mapping.dm
+++ b/code/controllers/subsystem/minor_mapping.dm
@@ -15,27 +15,25 @@ SUBSYSTEM_DEF(minor_mapping)
 
 /datum/controller/subsystem/minor_mapping/proc/trigger_migration(num_mice=10)
 	var/list/exposed_wires = find_exposed_wires()
-
-	var/mob/living/basic/mouse/mouse
 	var/turf/open/proposed_turf
-
-
 	while((num_mice > 0) && exposed_wires.len)
 		proposed_turf = pick_n_take(exposed_wires)
-
-		if(!istype(proposed_turf))
+		if (!valid_mouse_turf(proposed_turf))
 			continue
 
-		if(prob(PROB_MOUSE_SPAWN))
-			if(!mouse)
-				mouse = new(proposed_turf)
-			else
-				mouse.forceMove(proposed_turf)
+		num_mice--
+		if (prob(PROB_MOUSE_SPAWN))
+			new /mob/living/basic/mouse(proposed_turf)
 		else
-			mouse = new /mob/living/simple_animal/hostile/regalrat/controlled(proposed_turf)
-		if(proposed_turf.air.has_gas(/datum/gas/oxygen, 5))
-			num_mice -= 1
-			mouse = null
+			new /mob/living/simple_animal/hostile/regalrat/controlled(proposed_turf)
+
+/// Returns true if a mouse won't die if spawned on this turf
+/datum/controller/subsystem/minor_mapping/proc/valid_mouse_turf(turf/open/proposed_turf)
+	if(!istype(proposed_turf))
+		return FALSE
+	var/datum/gas_mixture/turf/turf_gasmix = proposed_turf.air
+	var/turf_temperature = proposed_turf.temperature
+	return turf_gasmix.has_gas(/datum/gas/oxygen, 5) && turf_temperature < NPC_DEFAULT_MAX_TEMP && turf_temperature > NPC_DEFAULT_MIN_TEMP
 
 /datum/controller/subsystem/minor_mapping/proc/place_satchels(amount=10)
 	var/list/turfs = find_satchel_suitable_turfs()
diff --git a/code/modules/mob/living/basic/basic.dm b/code/modules/mob/living/basic/basic.dm
index f7a386e9ba9..0473c09973c 100644
--- a/code/modules/mob/living/basic/basic.dm
+++ b/code/modules/mob/living/basic/basic.dm
@@ -89,9 +89,9 @@
 	var/unsuitable_atmos_damage = 1
 
 	///Minimal body temperature without receiving damage
-	var/minimum_survivable_temperature = 250
+	var/minimum_survivable_temperature = NPC_DEFAULT_MIN_TEMP
 	///Maximal body temperature without receiving damage
-	var/maximum_survivable_temperature = 350
+	var/maximum_survivable_temperature = NPC_DEFAULT_MAX_TEMP
 	///This damage is taken when the body temp is too cold. Set both this and unsuitable_heat_damage to 0 to avoid adding the basic_body_temp_sensitive element.
 	var/unsuitable_cold_damage = 1
 	///This damage is taken when the body temp is too hot. Set both this and unsuitable_cold_damage to 0 to avoid adding the basic_body_temp_sensitive element.
diff --git a/code/modules/mob/living/basic/vermin/cockroach.dm b/code/modules/mob/living/basic/vermin/cockroach.dm
index 2abca82218c..c4ce8833743 100644
--- a/code/modules/mob/living/basic/vermin/cockroach.dm
+++ b/code/modules/mob/living/basic/vermin/cockroach.dm
@@ -38,7 +38,6 @@
 	var/static/list/roach_drops = list(/obj/effect/decal/cleanable/insectguts)
 	AddElement(/datum/element/death_drops, roach_drops)
 	AddElement(/datum/element/swabable, cockroach_cell_line, CELL_VIRUS_TABLE_GENERIC_MOB, 1, 7)
-	AddElement(/datum/element/basic_body_temp_sensitive, 270, INFINITY)
 	AddComponent(/datum/component/squashable, squash_chance = 50, squash_damage = 1)
 	ADD_TRAIT(src, TRAIT_VENTCRAWLER_ALWAYS, INNATE_TRAIT)
 
diff --git a/code/modules/mob/living/simple_animal/hostile/regalrat.dm b/code/modules/mob/living/simple_animal/hostile/regalrat.dm
index 7f4f4637813..bd94d7508ba 100644
--- a/code/modules/mob/living/simple_animal/hostile/regalrat.dm
+++ b/code/modules/mob/living/simple_animal/hostile/regalrat.dm
@@ -1,4 +1,3 @@
-
 /mob/living/simple_animal/hostile/regalrat
 	name = "feral regal rat"
 	desc = "An evolved rat, created through some strange science. They lead nearby rats with deadly efficiency to protect their kingdom. Not technically a king."
diff --git a/code/modules/mob/living/simple_animal/simple_animal.dm b/code/modules/mob/living/simple_animal/simple_animal.dm
index 5eed9bbbce7..54688eba617 100644
--- a/code/modules/mob/living/simple_animal/simple_animal.dm
+++ b/code/modules/mob/living/simple_animal/simple_animal.dm
@@ -59,9 +59,9 @@
 	var/stamina_recovery = 5
 
 	///Minimal body temperature without receiving damage
-	var/minbodytemp = 250
+	var/minbodytemp = NPC_DEFAULT_MIN_TEMP
 	///Maximal body temperature without receiving damage
-	var/maxbodytemp = 350
+	var/maxbodytemp = NPC_DEFAULT_MAX_TEMP
 	///This damage is taken when the body temp is too cold.
 	var/unsuitable_cold_damage
 	///This damage is taken when the body temp is too hot.