Lunar Periodicity in Larva Release in the Reef Coral Pocillopora Damicornis at Enewetak and Hawaii

Simultaneous daily measurements of planulation in the reef coral Pocillopora damicornis at Enewetak, Marshall Islands and Kaneohe Bay, Hawaii showed phase differences between and within populations. At Enewetak, the time of maximum larva release occurred consistently between new moon and first quarter. In Hawaii, two morphological variants of this species were studied. The first type showed peak release of larvae near the lunar third quarter. The second consistently showed a peak between first quarter and time of full moon. A positive relationship was found to exist between environmental variability and degree of variation in the pattern of larval release.