We are continuing our Spotlight on Coral Series of Blog. This week we look at another or our 3 types of hard coral that we are fragmenting in our coral restoration project at Marine Conservation Costa Rica. So here’s an indepth look at Pavona gigantea…..
What is Pavona gigantea?
Pavona gigantea is known as plate coral or leaf coral. It is a common coral that grows in relatively shallow and protected areas. Pavona has a naturally occurring growth rate of between 9 and 12 mm each year and also grows large plate colonies. They have visible coralites with a width of between 3 and 6 mm. The colonies tend to have a furry appearance due to the extension of their tentacles during the day.
Restoration Success with Pavona gigantea
Pavona gigantea can be relatively easy to harvest and fragment, as it often grows in plate formation. The younger growth to the edge of a plate is often thin and can be easily harvested. The older growth is thicker and extremely dense. The Pavona has responded well to micro fragmentation in our restoration project. Pavona gigantea seems to be reasonably resilient to stress and we have had a low mortality rate.
Geographic Range of Pavona gigantea
Pavona gigantea is found in the pacific ocean, growing along the coast of middle america from Mexico to Ecuador and in the Galapagos and Cocos Islands. In the Mid- Western Pacific, it is found in reefs located in the middle of the ocean. This is around the body of water between Japan and Papua New Guinea.
Feeding methods of Pavona Gigantea
Corals consume particulate organic matter and absorb dissolved organic matter. However, their consumption of plankton is limited to zooplankton that is in the 200- 400 μm size range. They use their tentacles to obtain this food. The same as other hard corals, Pavona gigantea depends on receiving most of its energy from it’s symbiotic relationship with the Zooxanthellae. These use photosynthesis to harness energy..
Sexual Reproduction of Pavona Gigantea
Typically Pavona gigantea colonies are gonochoristic, broadcast spawners. This is that there are both male and female colonies releasing eggs into the water column. Spawning takes place at the beginning of the rainy season, normally between May and July. Interestingly, in a few studies of Pavona gigantea, hermaphroditic colonies have also been discovered! This is likely to be an example of sequential cosexuality. It is when corals can begin their reproductive life as males and then become hermaphroditic. It has been suggested that sequential cosexuality is an adaption to guarantee sexual reproduction and increase connectivity among populations.
Specific Living Conditions for Pavona gigantea
Temperature: 18 °C -29 °C
Salinity: 34- 37 parts per thousand
Depth: abundant between:0,5 -20 meters Ph: 8,1
Dissolved oxygen concentration: 4.55 mL/L
Nitrate concentration: 0.831 μmol/L Phosphate concentration: 0.357 μmol/L Silicate concentration: 1.776 μmol/L
We hope you learnt something. Thank you Sebastian for the great info and help with this. If you want to learn more about our project you can contact us here or apply to become a volunteer or intern here in Costa rica.