You still get that in the wasteland biome. Never remembered hearing it in the burnt forest biomes, but might not have been audible over the constant crackling of eternally burning cinders and the unsettling ant-walking-alligator shrieks of the burnt zombies. Kind of makes you wonder if they were living people caught up in the fire resulting from the catastrophe or if they were turned first and wandered mindlessly into the fire, as zombies are wont to do. Could actually be some workable lore there if we ever get a story mode for Navezgane prefab map.