What kind of bitey? Do they latch onto you and wrap around? If so maybe they are hungry, and need to be fed more or larger prey.
Or is it a defensive bite, where they just bite and let go?
If it's the latter i'd say it's because they aren't used to being handled, also the stress of moving to a new location can do that too.
If they are new acquisitions, try letting them settle in for a couple weeks, with no handling.