Crab Feces is one of those resources in Subnautica 2 that players dismiss as a joke until they realize it feeds directly into fuel production. Once your base starts demanding more power, you will want a reliable supply of this biological material well before that point arrives. The good news is that once you know where Coral Crabs hang out, farming becomes straightforward.
What is Crab Feces and what is it used for?
Crab Feces is a "coprolyte-like deposit of excreta" with extreme energy density, making it suitable as a bioreactor fuel. That description is doing a lot of heavy lifting, but the practical upshot is simple: this material is a biological crafting resource classified under the Materials category.
The only confirmed crafting recipe tied to Crab Feces right now requires processing 2 units at the Processor to produce a Biofuel Block. Biofuel Blocks are a key power source for base energy systems, so building a stockpile early prevents headaches later when your habitat starts drawing more power.
Because Subnautica 2 is currently in Early Access, future updates may add additional recipes that use Crab Feces. Grab more than you think you need now to avoid grinding later.
Biofuel Block crafting recipe
Where do Coral Crabs spawn?
Coral Crabs are the only confirmed source of Crab Feces in the game. These enormous crustaceans live among Coral Dome structures and use those formations for camouflage. At first glance a Coral Crab looks identical to a stationary Coral Dome sitting on the seabed, which is exactly why players walk past them constantly during early exploration.
The two best biomes for finding Coral Crabs are the North Raceway and the Leadzone. The North Raceway is the easier starting point because it sits within a manageable distance of the Lifepod.
How do you actually collect Crab Feces?
Here is the part most guides skip. You cannot just walk up to a Coral Crab and loot it. The creature drops Crab Feces only when it stands up on its legs. Until that happens, it sits motionless and looks like an ordinary piece of coral.
When a Coral Crab rises, it randomly deposits feces onto the sand nearby. The material looks similar to brown rocks, which makes it easy to miss if you are not scanning the ground carefully. One crab can drop one or two pieces per stand-up cycle, and the same individual can produce multiple drops in a single session.
Patience is the main skill required here. Work the farming route below to visit several crabs in sequence rather than waiting on a single one.
Crab Feces blends into the sandy seabed and looks nearly identical to small brown rocks. Scan the ground in a wide radius around each Coral Crab after it stands up, not just directly underneath it.
Coral Crab standing to drop feces
Best farming route: North Raceway
The North Raceway route gives you access to 8 Coral Crabs in a single loop. Starting from your Lifepod, follow these steps:
- Head 110 degrees east-southeast for roughly 179 meters. The Blackbox Chap signal works as a useful reference point for this heading.
- The first Coral Crab sits between two rock towers.
- Turn 30 degrees north-northeast past the platform built against a rock formation. The second crab is ahead.
- Head 45 degrees northeast and round the bend of the rock formation on your right. The third crab sits in a dusty open grass field.
- The fourth crab is a few meters northeast in the same grass field, just past a Coral Dome.
- Turn east from the fourth crab. A fifth is a short distance away near another Coral Dome.
- Head 105 degrees east from the fifth crab to find the sixth in an open area.
- Turn directly south from the sixth crab. The seventh and eighth crabs are past a small gap in the rock formation on the other side.
Each Coral Crab drops only 1 to 2 Crab Feces per stand-up cycle. Running the full 8-crab loop is far more efficient than camping a single creature and waiting.
Does Crab Feces respawn?
Community testing documented on resource tracking tools suggests that Crab Feces does respawn naturally near active Coral Crab territories after players leave the area and return later. Exact respawn timers are still being confirmed because the game is in Early Access and the underlying systems may change with patches.
For consistent supply, running the North Raceway loop, leaving the biome to handle other tasks, and returning later is the most reliable approach available right now.
Tadpole improves farming runs
Tips for efficient collection
- Bring extra oxygen support before heading into Coral Crab territory. Some nesting zones sit deeper than the starting area.
- The Seaglide or Wakemaker speeds up movement between crab positions significantly.
- Once you have the Tadpole vehicle, oxygen management during longer farming runs becomes much less stressful. For the materials needed to get there, check out guides on finding copper and sourcing lead since both are part of the Tadpole build chain.
- Scan the ground in a wide radius after each stand-up event. The feces can land several meters away from where the crab is standing.
For players working through survival games like this one, biological resources often feel like an afterthought until the mid-game hits and power demands spike. Crab Feces is a good example of a material worth stockpiling before you need it rather than scrambling for it later. The full collection of Subnautica 2 resource guides covers everything from quartz to creature enamel if you want to build out your materials supply in one session.