How many spawners are there on the birch island?

[sola haze]

I just want to conquer this island, but the cave spiders are the bane of my existence, as are the zombies. Does anyone know how many spawners there are? I've collected one zombie and one spider.

 

[Xavi | Goofy]

These are the statistics of the birch island:

Birch Forest
8 Coal Generators
2 Lapis Generators
14 Iron Generators
L18 | Zombie Spawner
L10, 12, 16 | Cave Spider Spawner

More statistics can be found here: https://www.cubecraft.net/threads/islands-boosters-crops-and-more.273711/