Coral mass spawning predicted by rapid seasonal rise in ocean temperature

Abstract

Coral spawning times have been linked to multiple environmental factors; however, to what extent these factors act as generalized cues across multiple species and large spatial scales is unknown. We used a unique dataset of coral spawning from 34 reefs in the Indian and Pacific Oceans to test if month of spawning and peak spawning month in assemblages of Acropora spp. can be predicted by sea surface temperature (SST), photosynthetically available radiation, wind speed, current speed, rainfall or sunset time. Contrary to the classic view that high mean SST initiates coral spawning, we found rapid increases in SST to be the best predictor in both cases (month of spawning: R 2 ¼ 0.73, peak: R 2 ¼ 0.62). Our findings suggest that a rapid increase in SST provides the dominant proximate cue for coral mass spawning over large geographical scales. We hypothesize that coral spawning is ultimately timed to ensure optimal fertilization success.

Spawning of coral reef invertebrates and a second spawning season for scleractinian corals in the central Red Sea

“…data), and have shown to best predict timing of spawning in scleractinian corals (Keith et al. ) The Giovanni online data system offers rapid data exploration and analysis of satellite data from NASA Earth (Acker & Leptoukh ).…”

“…In Indo‐Pacific scleractinian corals, the time of year during which spawning occurs is best predicted by a rapid increase in sea surface temperature (SST) (Keith et al. ). However, although the timing of gamete release is expected to be synchronous among shallow, mid‐depth, and mesophotic populations of a given species, as shown with the Atlantic coral species Orbicella faveolata ( Ellis & Solander 1786) (Holstein et al.…”

Can mesophotic reefs replenish shallow reefs? Reduced coral reproductive performance casts a doubt

“…The phenology of coral reproduction is assumed to be governed on different temporal scales by a mixture of environmental factors, most notably temperature (Keith et al. ), solar insolation (van Woesik et al. ), and lunar and twilight cues (Harrison et al.…”

Coral reproduction at Hall Bank, a high latitude coral assemblage in Western Australia

“…Therefore, peak spawning on high latitude reefs on both the east and west coast of Australia occurs when water temperatures are at the yearly maxima, presumably in order to maximise both fertilization success and larval survivorship . Low wind speeds and high rainfall have also previously been associated with the time of spawning, however, more recent work on spawning cues in the Scleractinia does not support such an association (see discussion in Keith et al 2016). Plesiastrea versipora was sampled on 4 occasions and had immature gametes on each occasion except in May 2009, when all 14 colonies sample were mature.…”

“…Environmental variables hypothesized to serve as proximate cues to synchronise spawning (see Keith et al 2016) ). These data were obtained for the Fremantle station (located approximately 2 km east of Hall Bank) for the period 1890 to 2000 from the Australian Bureau of Meteorology (www.…”