I'm unsure. They seem to be coming from the ferry, but it doesn't seem to have the capacity for how many we're seeing.

[He kicks one that managed to avoid the ice. He's not a fan of vermin, but if they weren't threatening to eat all their food he might have ignored them. But a swarm that was endangering their survival would have to be dealt with.]

I don't know where they're going either. We don't have trash or storehouses to attract rats.