They all sounded like an eminently practical and well-thought-out approach to dealing with the uncooperative nature of a natural phenomenon, i.e. bees.
For comparison: Bee-keeping ordinances from Ontario (not that I have any particular brief for Canadian law, these were just the first to come back from the Great Gazoogle):
Right of owner to pursue and recover swarm
- (1) Subject to subsections (2), (3) and (4), where a swarm of bees leaves a hive, the owner of the swarm may enter upon the premises of any person and recover the swarm. R.S.O. 1990, c. B.6, s. 3 (1).
Where owner declines to pursue swarm
(2) Where the owner of a swarm of bees that leaves its hive declines to pursue it and another person takes up the pursuit, such other person is subrogated to all the rights of the owner in respect of the swarm. R.S.O. 1990, c. B.6, s. 3 (2).
Owner of premises to be notified
(3) Where the right to recover a swarm of bees is claimed under subsection (1) or (2), the person claiming the swarm shall notify the owner of the premises on which the swarm has settled before entering the premises and shall compensate the owner for any damage to the premises caused by the entry. R.S.O. 1990, c. B.6, s. 3 (3).
When right of property in swarm lost
(4) Where a swarm of bees leaves a hive and settles in an occupied hive owned by a person other than the owner of the swarm, the owner of the swarm loses all right of property in the swarm. R.S.O. 1990, c. B.6, s. 3 (4).
So to sum up, German laws are no weirder than Canadian ones.