Intern life in Lockdown

The life of a marine conservation intern is a busy one. With current times our interns are safely back home and helping us from afar. As part of this one of our interns, Sebastian Moesbergen has been researching our coral species here in Costa Rica. Our first one here is Porites lobata.It is one of our 3 types of hard coral that we, at Marine Conservation Costa Rica, are fragmenting in our coral restoration project on the Pacific coast of Costa Rica. We thought you would be interested in a more in depth look at this interesting coral…so here goes for some cool coral facts!

What is Porites lobata?

Porites Lobata Costa Rica

Porites Lobata is a common reef-building coral that can grow into very large colonies, building large coral reefs throughout its range. This species forms large hemispherical or helmet-shaped structures that can reach several meters across. For this reason, Porites lobata is also known as “Lobe Coral”. Though they appear to be very large, only the outer few millimeters represent living tissue, while the rest is a calcium carbonate skeleton. Porites Lobata structures only grow a few centimeters each year and may be hundreds of years old. Each structure is actually a colony of several genetically identical animals living together. In some areas, several colonies grow together to form a nearly continuous stretch of Porites Lobatas that may be tens of meters (or more) long.

Restoration Success with Porites Lobata

Coral restoration in Costa Rica

We were initially uncertain about using Porites lobata in our restoration project, as it is a notoriously slow growing coral. However, after success with 2 other species of hard coral, we decided that Porites was the obvious choice to expand our project. It is one of the dominant massive corals in our region, along with Pavona gigantea. We initially tested fragmenting Porites lobata on a small scale. Only micro fragmenting 40 new fragments that went into 2 nurseries as 2 different locations. Initially, there was little growth in either nursery, but after 2 months we had significant growth. After 3 months most fragments were at least doubled if not tripled in size. In the last 6 months we have expanded our Porites lobata nurseries and look forward to outplanting Porties lobata back onto our reefs in Costa Rica.


Geographic Range of Porites lobata 

Porites lobata has a huge geographic range throughout tropical and subtropical regions. Porites Lobata can be found from East Africa, the Red Sea and the Gulf of Aden. They can be found all the way through Indonesia and Australian waters to the Pacific coasts of California and Central America.


Feeding methods of Porites lobata

Many corals can function as carnivores, using their tentacles to capture small planktonic animals drifting over the reef. Special stinging cells that line the surfaces of the polyps’ tentacles entangle and paralyze their prey. Other corals are suspension feeders. They use hair-like structures called cilia to collect particles of organic matter that drift down from above. The polyps of Porites lobata  are so small that researchers question if they are actually capable of capturing prey.

Luckily, corals also act as primary producers. Single-celled algae called zooxanthellae live within the tissues of reef-building corals in a symbiotic relationship. Using sunlight and nutrients from the water and their coral hosts, zooxanthellae generate energy-rich compounds through photosynthesis. These carbon-rich products may be particularly important in the energy budget of Porites lobata.

Sexual Reproduction of Porites lobata.

Coral restoration project costa rica

Unlike many species of corals, Porites lobata colonies are gonochoristic. This means they are either male or female, not both. They reproduce via broadcast spawning. This is where several individuals release their eggs or sperm into the water column at the same time. This method increases the likelihood that eggs become fertilized and reduces the danger from egg predators near the reef surface. Within a few days after the eggs hatch, larvae settle onto the reef surface and begin to form new colonies.


Specific Living Conditions for Porite lobata some scientific data for you…

Temperature range that the corals like is between 18 °C and 30 °C , for example, if the water temperature is higher than 30°C the coral starts bleaching). The Salinity ideal is between: 34 and 38 % and depth range between 0 and 30 meters. Ideal Ph is between 8,4 -7,7. They have an oxygen demand of 0,21 (μmol L−1 h−1) and a bacterial cell yield of  0,06 – 0,10( cells × 105 mL−1 h−1).


Want to become part of our team?

Want to join our team at Marine Conservation Costa Rica in the future to do a coral internship? Please contact us at info@marineconservationcostarica.org

Written by Sebastian Moesbergen