Axolotls and Glow Squids spawn in every biome?

I am not sure if this intended or not but Glow Squids and Alolotl's spawn everywhere. Aren't that supposed to spawn in specific biomes only?

I have built my base in a Forest biome at Y level very low (to prevent Phantoms) and all my water areas (water elevators, etc) are filled up with Glow Squids and Axlolotls now. Disaster!