According to Brian Clark however, the lack of ice bees is not in the original arcade version:
Not sure why the ice bees don't seem to appear in this version since they are only in the AC version. Not sure if it's an alternate version or a glitch. The FDS version technically has the bees, but replaces their sprite with the bird sprite, though they still don't count as birds in the score tally at the end of the level. The butterfly was replaced by a blue pterodactyl in the FDS version.
"Blue pterodactyl" I assume may be blue condor, but I may be wrong.
With the recent release of Arcade Archives: Clu Clu Land (and earlier, Donkey Kong 3, Sky Skipper, others I can't remember from head) does anyone know if there are other examples?