Timing of planulation by pocilloporid corals in the northwestern Philippines

Abstract

We determined the lunar, seasonal, and diel timing of larval release in several species in the scleractinian family Pocilloporidae at Bolinao in the northwestern Philippines. All of the species exhibited remarkable lunar periodicity in planula release, with distinct timing in the lunar calendar. Despite confinement of peak larval release between the first quarter and full moons in 4 species (Pocillopora damicornis, P. verrucosa, Stylophora pistillata, and Seriatopora guttatus), only the 2 Pocillopora species experienced significant overlap in release times. Disparate lunar timing, on the other hand, was exhibited by the 3 Seriatopora species (new moon for S. caliendrum, last quarter moon for S. hystrix, and full moon for S. guttatus) during warm-dry months, although during seasons with low planulation rates the timing for the former 2 species seemed to overlap. Generally, lunar reproductive patterns in each species were seasonally consistent despite strong variations in larval output. The highest rates of planulation were recorded during the warm-dry months (March to May) and the lowest during the warm-wet months (June to October), except for P. damicornis, in which the lowest rate occurred during the cool-dry months (November to February). The timing of release in P. damicornis is mainly during the dark period of the diel cycle, with a peak at ca. 02:30 h. This report highlights the variation in timing of planulation among closely related coral species and compares temporal planulation data in the Philippines, which lies within the Indo-West Pacific center of coral diversity, to available data on brooding pocilloporid corals from other biogeographic regions.KEY WORDS: Pocillopora · Seriatopora · Stylophora · Reproduction · Planulae · Lunar periodicity · Seasonality · Bolinao · BrooderResale or republication not permitted without written consent of the publisher

Plasticity in lunar timing of larval release of two brooding pocilloporid corals in an internal tide‑induced upwelling reef

“…The use of an aquarium system to study larval release allowed for a more detailed examination than would be possible in situ, particularly in recording the day and time of larval release throughout the year. The timing of larval release from corals in aquaria and in situ is similar as long as the physical conditions in the aquaria adequately match those in the field (Richmond & Jokiel 1984, Fan et al 2002, Villanueva et al 2008). …”

“…They conduct internal fertilization and release buoyant planktonic larvae which may disperse widely or settle quickly (Harrison & Wallace 1990, Richmond & Hunter 1990, Fan et al 2002, Villanueva et al 2008. Larval release in these species is synchronized to the lunar phase and occurs throughout the year at low latitudes and seasonally at high latitudes (Harriott 1983, Richmond & Jokiel 1984, Tanner 1996, Fan et al 2002, Villanueva et al 2008.…”

“…They conduct internal fertilization and release buoyant planktonic larvae which may disperse widely or settle quickly (Harrison & Wallace 1990, Richmond & Hunter 1990, Fan et al 2002, Villanueva et al 2008. Larval release in these species is synchronized to the lunar phase and occurs throughout the year at low latitudes and seasonally at high latitudes (Harriott 1983, Richmond & Jokiel 1984, Tanner 1996, Fan et al 2002, Villanueva et al 2008. Typically, the lunar timing of larval release of brooding coral species at a single location is highly consistent with a specific moon or tidal phase, al though this timing varies among biogeographic regi ons (Richmond & Hunter 1990, Villanueva et al 2008, Baird et al 2009, Harrison 2011.…”

“…The correlation between lunar timing of larval release and tidal phase suggests that ecological significance lies in either maximizing larval dispersal during spring tide or larval retention and local recruit ment during neap tide (Tanner 1996, Fan et al 2002, Villanueva et al 2008, Harrison 2011. The lunar cycle of tidal and moon phases may be the major proximate environmental factor controlling the lunar periodicity of larval release.…”

Enduring physiological and reproductive benefits of enhanced flow for a stony coral

“…For example, many species brood planulae, but in some, the larval development occurs in the water column (Harrison and Wallace 1990). P. verrucosa shows contrasting modes of larval development in different locations: It is a brooder at Enewetak Atoll (Stimson 1978) and Bolinao (Villanueva et al 2008), while it seasonally broadcast spawns in the Red Sea (Fadlallah 1985;Shlesinger and Loya 1985) and in the Republic of Maldives (Sier and Olive 1994).…”