▁There ▁is ▁a ▁black ▁spot ▁at ▁the ▁top ▁of ▁the ▁head ▁and ▁another ▁larger ▁spot ▁of ▁black ▁at ▁the ▁base ▁of ▁the ▁tail . ▁This ▁latter ▁dark ▁patch ▁may ▁serve ▁to ▁dist ract ▁pred ators ▁by ▁encourag ing ▁them ▁to ▁attack ▁the ▁tail ▁rather ▁than ▁the ▁head ▁end . ▁ ▁Distribution ▁The ▁bl uest ri pe ▁but ter fly fish ▁is ▁en demic ▁to ▁the ▁Hawai ian ▁Islands ▁where ▁it ▁is ▁described ▁as ▁being ▁abund ant ▁on ▁cor al ▁and ▁rock y ▁re ef s ▁down ▁to ▁depth s ▁of ▁about ▁. ▁ ▁E col ogy ▁Some ▁but ter fly fish ▁are ▁cor all iv ores , ▁feed ing ▁almost ▁exclus ively ▁on ▁cor als . ▁These ▁usually ▁have ▁m ating ▁systems ▁involving ▁a ▁pair ▁bond , ▁but ▁the ▁bl uest ri pe ▁but ter fly fish ▁is ▁an ▁om n iv ore , ▁which ▁means ▁it ▁lives ▁in ▁a ▁more ▁resource - rich ▁environment , ▁where ▁it ▁is ▁easier ▁to ▁find ▁sufficient ▁food . ▁As ▁a ▁result , ▁males ▁of ▁this ▁species ▁operate ▁a ▁ha rem ▁system , ▁def ending ▁a ▁territory ▁which ▁includes ▁up ▁to ▁four ▁smaller ▁female ▁territ ories . ▁ ▁Having ▁a ▁general ised ▁di et , ▁the ▁bl uest ri pe ▁but ter fly fish ▁is ▁sometimes ▁kept ▁in ▁re ef ▁aqu aria ▁where ▁it ▁is ▁easier ▁to ▁maintain ▁than ▁cor all iv orous ▁types . ▁Spec im ens ▁are ▁har v ested ▁from ▁the ▁wild ▁and ▁it ▁is ▁sometimes ▁difficult ▁to ▁get ▁the ▁fish ▁to ▁eat ▁in