In three skeleton key what do the rats do after they immediately get on the island?

In "Three Skeleton Key," after the rats arrive on the island, they swarm the lighthouse and begin to attack the lighthouse keeper and his companions. The rats are described as overwhelming in number and ferocity, creating a terrifying situation for the men. They gnaw at anything in their path, driven by hunger and desperation, ultimately leading to a harrowing struggle for survival. The relentless assault of the rats symbolizes both physical and psychological terror for the protagonists.