Despite All Odds, Coral Reefs Are Thriving in the USVI
Coral reefs are thriving at depths of 100 – 300 feet right here in the U.S. Virgin Islands.
Recent discoveries by scientists at the University of the Virgin Islands have shown that there are a great number of magnificent deep coral reefs in the area, particularly at the south side of St. Thomas on the Grammanik Bank and reaching out toward Culebra. It is estimated these reefs cover between 100 – 230 square kilometers and are home to over two hundred million corals! Early research shows that the corals found at these depths may be closely related to shallow water species and potentially may even be the same species. Interestingly, even those corals suspected to be the same as those found in shallow water look significantly different at depth. Studies are being conducted in order to determine a genetic relationship with their shallow-water cousins or if they are new species entirely.
Deepwater corals tend to be plate-like in order to absorb more light. These delicate branching forms can grow as fast as shallow water corals in some cases, but are often fragile and vulnerable to disturbance from anchors.
research at extreme depths
Viktor Brandtneris, is the technical mixed-gas rebreather diver for UVI with over 1500 dives in his logbook spread across 12 nations—including the Galapagos Islands, Easter Island, Israel, and the US Virgin Islands. Viktor received a bachelors degree in Marine Sciences and Biology from the University of Miami Rosenstiel School, and a masters degree from the University of the Virgin Islands in Coral Reef Ecology. He also has five authorships on peer reviewed journal articles.
Viktor is deeply engaged in the mesophotic (deep water) research taking place at the University where his technical diving experience is essential. To dive and conduct research at depths up to 230’, a rebreather is required. Rebreathers do just that: they recycle the air you breathe. When you exhale, carbon dioxide is removed through a process called scrubbing and the unused oxygen that was exhaled is recirculated. A mixture of air, oxygen, and helium (TRIMIX) is used in rebreathers. Because oxygen becomes toxic below 20’, potentially resulting in seizures, researchers must use gas mixtures with low oxygen. Helium, as an inert gas, is used in place of some of the nitrogen to lessen narcosis, also known as the “rapture of the deep”. When a diver experiences narcosis, the sensation is quite similar to being intoxicated. Divers may experience a feeling of tranquility, euphoria and loss of focus. As lovely as that may sound, diving while “drunk” can be quite dangerous because focus and judgment are impaired, accompanied by a loss of coordination.
Very few universities with marine science programs have rebreathers. UVI is has four. In this photo Dr. Tyler Smith installs water temperature probes at 165 feet off Wolf Island, Galapagos, Ecuador.
As a deep diver, nitrogen narcosis is something you learn to anticipate and manage. Because of the limitations of bottom time, dives necessarily become very goal-focused. It takes approximately 70 minutes to ascend from a 19 minute bottom time dive to 220 feet. Viktor has learned to manage anxiety and narcosis by using mantras to get and stay centered and focused. Concentrating on his breathing and being fully focused on the dive’s mission is a proven strategy for him.
The mesophotic reef system here in the Territory is one of the best studied and mapped in the world as a direct result of the work of Viktor and Dr. Tyler Smith, Associate Research Professor of Marine Science at UVI. This is due in part to the high level of marine research taking place at UVI, and the fact that the U.S. is one of the few countries that invest heavily in sciences, with great benefits to the economy and society. Indeed, funding from NSF EPSCoR has been instrumental in making this work possible at the University.
That investment is showing results
Seafloor mapping of the ocean floor south of St. Thomas is on par with the best in the world. The resulting bathymetrc maps suggest a huge area of mesophotic reefs in the USVI. Very few other mesophotic areas in the Caribbean have been studied at all. Work at UVI suggests an impressive potential for healthy and flourishing mesophotic reefs throughout the whole of the Caribbean.
Smashed plate corals on the Grammanik Bank at 220 feet depth. Increasing awareness of these habitats will help to protect these ancient coral reefs from irreversible damage. Notice the rope cutting across the coral.
It is of vital importance that mesophotic reefs are preserved. There is so little known about the deep water reefs, and indeed most people don’t even know they exist. Tragically, a vibrant lettuce coral reef at 220’ in front of the Grammanik Bank that was discovered in 2011 and incorporated in the USVI Territorial Coral Reef Monitoring Program, has already been significantly damaged, with the cover of coral reduced by 50%. The reef exists at the unprotected border of the Grammanik Bank fish spawning closure, and the apparent cause of reef decline has been breakage of delicate corals by anchoring with steel reef claws. An abandoned reef claw and large amounts of rope debris appeared at the site in 2012. A lack of knowledge of the treasures that exist at the deepest regions of our islands has been devastating.
Viktor Brandtneris dives with hammerhead sharks in the Galapagos Islands, Ecuador
And yet, there is hope
Viktor’s personal mission is to chart mesophotic reefs throughout the Caribbean and educate communities and governments about their significance. He has found there is great misconception about the conditions of coral reefs and that often this misconception can lead to apathy. As a marine scientist he is commonly asked “How can you stand to do what you do, when everything you love is dying?” The simple answer is that it’s not.
The truth is, with all the news of dead and dying coral reefs, you’re only hearing a part of the story. Over the past 15 years much work has been done on the potential for coral and fish refuges—places where heavily threatened coral reef species might cling to life in the face of climate change, pollution, overfishing, and other human threats. Coral reefs in Israel, Panama, Curaçao, and St. Thomas have all been identified as potential refuges for coral and fishes amongst so much reef loss. Corals deeper than 100 feet have fared far better against rising ocean temperatures than their shallow counterparts — in the past two decades the USVI has lost over 70% of corals in water less than 100 feet deep, but in waters deeper than 100 feet the losses have been much less and reefs are still healthy and robust.
This summer on the TEDx Saint Thomas stage Viktor will speak to the community about the work being done at UVI on deep coral reef refugia. He will share on the efforts made in the past decade to better understand and protect deep reefs both in the territory, and across the world. He will share information about novel methods developed to conduct this research, and discuss the importance of never giving in to the constantly negative news stream. Viktor will also use this platform to share his mesmerizing photos and videos taken at extreme depths. We will link to his TEDx talk here once it becomes available.