Here's why:
* Hermit crabs are marine crustaceans: They need access to saltwater to survive. They live on beaches, in tidal pools, and in the ocean.
* The Amazon rainforest is a freshwater environment: It is a dense, humid forest with rivers and lakes, but no saltwater.
While hermit crabs may be found in some coastal areas near the Amazon, they are not native to the rainforest itself.