A new study that was recently conducted tested how well staghorn coral skeletons withstand the forces of nature and humans. This gives us information about how we need to keep this species of coral safe, and how to transplant coral into the wild. So, what did the team of researchers find out and will this really help coral reef restoration and conservation? Is it possible to out plant staghorn corals successfully?
What Are Staghorn Corals?
Staghorn corals are a species of Acropora stony coral that is made up of cylindrical branches. These branches can grow over two meters in length! They are found in reefs in the Caribbean Islands, the Florida Keys, and the Bahamas.
According to National Geographic, staghorn corals can grow up to two inches a year. For hard corals, this is pretty fast. New colonies of staghorn corals form when branches break off the main coral and fall onto the substrate in the ocean. These branches then attach themselves to the substrate and start growing.
According to the National Oceanic and Atmospheric Administration, staghorn corals are extremely important to the coral reefs in the Caribbean. They are one of the three main corals that have built these reefs and they provide refuge to a lot of marine life because of their structure.
Staghorn corals rely heavily on the zooxanthellae in their tissue for nutrients. Because of this, when bleaching occurs, many staghorn corals do not recover and die. The level of staghorn corals in coral reefs has declined dramatically in recent years. According to the National Oceanic and Atmospheric Administration, a disease event in the early 1980s also caused a great decline in staghorn corals. They are also threatened by ocean acidification which makes it more difficult for them to build their skeleton. Ocean acidification occurs when carbon dioxide is absorbed into the ocean that decreases the pH levels in the water.
According to a research article published in 2020, 90% of the population of staghorn corals have died since the 1970s. This is because of bleaching and disease.
What Is Being Done To Help Staghorn Corals?
Because staghorn corals are such a major part of so many coral reefs and provide shelter and food to a range of marine life, the decline of this coral species is worrying.
Because of this, scientists have been adding staghorn corals that are bred in a nursery, into the coral reefs. But in order to do so, it is helpful to understand what affects staghorn corals and what we need to focus on in order to help them thrive in the ocean.
According to Science Daily, researchers from the University of Central Florida have concentrated their research on the strength of the skeleton of staghorn corals. They wanted to find out how these corals protected themselves from natural stressors and human interaction.
The researchers tested the corals by subjecting them to stressors that were higher than what was exerted by the ocean ways. In the study, they discovered that the staghorn corals skeleton has a special safety feature. The coral’s skeleton has pores that relieve the pressures of an impact, protecting the skeleton which did not crack or break.
This gave the researchers an understanding of what the staghorn corals can withstand and what they can not. This means that when staghorn corals are being put into the ocean, they can be placed in an environment where the structure of their skeleton will survive and hopefully thrive.
There are a few projects that are working on growing and outplanting staghorn corals into coral reefs in order for them to grow and the population to recover. The Coral Restoration Foundation has been working to grow and outplant coral, developing ways to propagate the corals by fragmentation.
Coral fragments are hung off coral trees and placed on the ocean floor. When they have grown to a certain size, they are then placed in coral reefs. Since 2012, the Coral Restoration Foundation has outplanted over 120,000 corals amongst the Florida coral reefs. One of these corals that are included in the project is the staghorn coral.
The National Oceanic and Atmospheric Administration have an in-depth recovery plan for elkhorn and staghorn corals that aims to rebuild the numbers of these corals in the reefs.
Is This Progress Good Enough?
The work that these scientists and conservationists are doing seems pretty great. In learning about the skeleton of the staghorn coral we know what it will and will not withstand. This will help the outplanting of staghorn corals into the reefs. With more knowledge comes more success, and the situation regarding staghorn corals might improve because of the amount of outplanting projects there are.
However, the long term potential of outplanting staghorn corals to the reefs is not fully known and a study that looked into if outplanted corals survive suggested that the rate of survival decreased rapidly.
If the issues in their habitat are still there, and global warming and human interaction are still threatening staghorn corals, putting staghorn corals into the habitat will just create more dead corals. We need to tackle the root causes of why staghorn corals are under threat and bring about big change before it is too late.
Of course, scientific studies of threatened corals are very important. The study of the skeleton of staghorn corals does provide more understanding of the coral and this can only help the cause. In learning about staghorn corals we are able to help them more.
It is also necessary to have these corals in a nursery being bred. Staghorn corals are an endangered species so we need to look after these corals in nurseries or labs in case they go extinct in the ocean.
However, alongside placing these corals back into the reefs we must work on protecting the habitat that they are in. We must tackle global warming and ocean acidification as these are causes of staghorn corals dying. We must manage the stress levels of these corals.
Without tackling the causes of staghorn coral deaths, outplanting them will make no real difference in the long run.