Past Research Results

The FIU Medina Aquarius Program make saturation diving a safe and cost–effective tool for scientists from around the United States to conduct experiments beneath the sea. Aquarius missions, 120 in all conducted in Florida between 1993 – 2013, are among the most productive ever conducted using an underwater lab.

Significant discoveries made using Aquarius include the following:

Ultraviolet radiation damages coral reef environments

Corals are sensitive to ultraviolet (UV) radiation. In fact, many produce chemicals that act as a sun block, similar to the sun block people use at the beach. The problem for reefs is that many corals do not produce enough sun block, and when the water is clear and calm, more UV light penetrates deeper into the water where it can damage corals.

Experimental studies conducted from Aquarius document that UV radiation, which is increasing worldwide because of decreases in the ozone layer, is damaging coral reefs, even at present day intensities. Aquarius gives scientists time to set up complicated experiments and obtain results that would have taken 10 times longer to achieve.

Sewage pollution, water quality affect Florida Keys National Sanctuary

One of the greatest threats to the health of coral reefs in Florida and worldwide is the decline in water quality, especially from sewage pollution. Studies conducted from Aquarius measure natural cycles relating to nutrient chemistry and the potential for sewage–contaminated water to affect reef organisms.

Aquarius scientists documented natural variation in water quality caused when water from the Gulf Stream makes its way onto shallow reefs. Using the extended bottom time provided by Aquarius, scientists also installed monitoring wells to determine if sewage–contaminated ground water is making its way to the reefs where it could affect the condition of the reefs.

Chemical warfare on the reefs leads to drugs from the sea

Many coral reef organisms like sponges and corals produce chemicals that have significant pharmacological potential. The chemicals protect the reef organisms from being eaten because they are distasteful or keep them clean as antifouling paint is used to keep the bottom of boats clean. Because many coral reef organisms live attached to the bottom (where they can’t swim to escape or hide), these chemicals provide a defense against predators.

Work conducted from Aquarius investigates this chemical battlefield, and pharmacological companies are using extracts from reef organisms to determine if these chemicals might also make useful drugs. Drugs obtained from nature account for the majority of products available to fight cancer or to treat arthritis and heart disease.

Underwater vision: Now you see it, now you don’t

Basic properties of light underwater are poorly understood, and in coral reef environments where color is so spectacular, scientists are just beginning to understand how animals use light and color to communicate. People don’t usually think about communicating using color, but fish and invertebrates use color to show aggression, attract attention or to escape from predators.

Much of what we know about our own brains and vision comes from studies of more primitive life forms, and work conducted from Aquarius improves our understanding of the chemistry of color vision and the ability to see in the dark using polarized light, which has important applied applications.

Fossil records hold important clues about what is happening on reefs today.

Many things are happening in our oceans that scientists can’t explain. One of the biggest obstacles is that natural cycles which determine how oceans work often occur on time scales that are significantly greater than the careers of investigating scientists.

One way to get around this is to use long–term records captured in the fossil record. Coral reefs are unusually well preserved, and scientists are using Aquarius to obtain information about how things happening today compare to things that have happened over thousands of years. That way, they can determine if current changes are cause for concern or are just part of the natural way things happen in oceans. Corals are feeding monsters in the sea, if you look close enough…

Most people think of corals as pretty rock–like animals, but they are voracious predators. Using tentacles, they capture small creatures which swim by. Some of these animals seem to be aware of the corals and have escape behaviors that allow them to survive contacts with coral tentacles. This all happens at a near–microscopic level and could only be studied using the computer and electronic capabilities and extended bottom time made possible by Aquarius.

The health of corals is directly related to how they feed, and since more and more corals are dying, understanding their feeding biology is the first step to understanding possible causes of death. Pollution changes the quality and quantity of food available to corals. Water movement affects coral feeding because currents bring plankton into contact with the corals. Without Aquarius, the secrets of coral feeding would remain undiscovered.