Coral Spawning in the Maldives 2023 Q3-Q4 Updates

Please also see our main Coral Spawning reports page, from 2013 onwards, including our pioneering lab work in Oct-Nov 2021.

July 2023 Observations – Gametogenesis

Tracking Gametogenesis

At Landaa during July, we surveyed both wild and frame colonies of mature Acropora latistella in preparation for the upcoming full moon on 1 August. White and pale gametes were observed.

Our observations at Kuda Huraa this month included:

  • White eggs were found in six Acropora species across the Starfish, Blue Hole, and Water Villas sites
  • White, pale, and pigmented eggs were found in Acropora latistella colonies located in the Starfish and Blue Hole sites
Reefscapers coral gametogenesis Acropora plantagenea

Coral gametogenesis – white eggs in Acropora

August Observations – Coral Spawning (presumed)

Our observations at Kuda Huraa this month included:

  • During August, white coral gametes were observed in 41 coral colonies across eight different Acropora species
  • In July, several colonies of A.latistella had been identified with white and pigmented eggs. In August, when these colonies were revisited, most had since lost their eggs after a presumed spawning event.

At Landaa, with spawning season approaching, we were checking colonies of various Acropora species for the development of gametes. Colonies of A.latistella have shown varying degrees of pigmentation since July; in mid-August, two colonies were observed with pale-pigmented gametes, while most others remained white/pale. In total, white eggs were recorded in nine different Acropora species, including one specific colony of A.secale that had spawned in April 2023.

Presumed Coral Spawning Event

  • 1 August full moon – spawning checks were carried out over the period, but we did not observe any spawning, or loss of gametes.
  • 16 August new moon – no spawning events or loss of gametes.
  • 31 August full moon – from our periodic surveys, we noted that four wild colonies of A.latistella had already lost their gametes, but we did not observe the actual spawning event.

September Observations

  • 31 August (full moon) – we held nightly snorkels around this period, August into September, but no spawning was observed, and no eggs were collected.

With spawning season approaching, we are checking mature coral colonies (mainly on our frames) for the development of gametes. White immature eggs have been now been recorded in 12 different species of Acropora over August to September.

  • Pale pigmented gametes observed in species of Acropora and Sarcophytia
  • White gametes observed in several Acropora species
Reefscapers coral gametes Maldives

White and pale eggs in various Acropora species were observed and documented at Kuda Huraa in September

Reefscapers white coral eggs (Acropora sp)

Top: A.humulis / A.secale
Bottom: A.vermiculata / A.rosaria

October Observations

At Kuda Huraa this month, we conducted 13 hours of spawning monitoring, over six nights across two locations. We recorded mature pigmented gametes in various Acropora species, indicating which colonies would be more likely to spawn in the coming weeks.

At Landaa, we have been checking colonies of a variety of Acropora species for the development of gametes. Across several sites around the island, gradual pigmentation has been observed in various colonies of Acropora species, with colours ranging from white eggs to deeply pigmented eggs. We anticipate spawning will be split between the October full moon and the November full moon.

October Coral Spawning

Reefscapers coral spawning Maldives
Reefscapers coral bundling & spawning Maldives
  • 27 October – coral spawning nets were placed over mature colonies of secale. Following the nights when these colonies did not spawn, the nets were removed at 08:00 to reduce coral stress, and reattached the same evening at 16:00. Our intern, Damaris, has been designing variations on our gamete collection devices and experimenting with fishing weights and drawstrings.
  • 29 October (full moon) – we performed nightly snorkels around this period, looking for signs of spawning. Our checks start before sunset for some species (A.tenuis, A.valida, A.vermiculata) and continue for more than one hour after sunset for all other species.
  • 31 October – 13 colonies were observed to spawn, including: secale, A.humilis, A.plantaginea.

November Observations

Coming soon!

November Coral Spawning

Coming soon!