Add custom mobs to vanilla biomes

[sixbullets]

This is probably incredibly simple but I'm not sure how I can modify the "spawners" list for vanilla biomes. I currently have custom mobs successfully spawning in my custom biomes.

Can this be done in the main mod file?

[sixbullets]

I figured it out. For anybody interested, I added a listener in my main mod file for the BiomeLoadingEvent. When the biome name equals the biome(s) I'm interested in, I add my custom mob to the spawner data.