However , where the European honey bee has been imported , Vespa velutina finds them easier prey than Apis cerana because Apis mellifera have not been subjected to selection for countering concentrated hawking by hornets .
The guard bees also ball hornets to death .
Where the European honey bee has been imported , Vespa velutina finds them easier prey than Apis cerana because Apis mellifera have not been subjected to selection for countering concentrated hawking by hornets .
The guard bees also ball hornets to death .