What do I do?

It has been asked, and rightfully so, what it is that I do out here? Why does someone pay me to SCUBA dive? I work for the Coral Reef Ecosystem Division (CRED) of the Pacific Islands Fisheries Science Center. This program has been monitoring the health of coral reefs around all Pacific islands under US jurisdiction every 2 years since 2002. I dive with a team of 8 people and the goal is to evaluate the overall health of the coral reef at each site we visit. We lay out two transect lines (75’ measuring tapes) that we swim along taking measurements. We can use this as a representative sample of the environment in that particular area. I identify what is on the bottom every 6” along the line - coral, algae, sea star, sponge, etc. - so that at the end of the dive I can list the species and calculate the percentage of the bottom that is covered by each of them. I can compare this data to past years to see what, if anything, is changing. This is helpful in spotting invasive species or when things such as corals are dying off. For example, when a ship runs aground on the reef, a lot of contaminants are spilled into the water. This will often cause an algal bloom for many years afterwards, which can overgrow the coral. It is important to know what the environment was like beforehand to be able to tell how much damage was done and how, if possible, to correct it. The rest of the members of my team do similar things with small fish (less than 18”), invertebrates (sea stars, urchins, anemones, hermit crabs, etc) and coral. The coral divers count the total number of coral colonies and measure them. This allows them to see if new corals are coming in to an area or if there has been some sort of die off.

The two other teams on the ship are oceanography and the tow team. The oceanography team deploys instruments to measure a wide variety of parameters such as nutrients, pH, currents, and temperature. This helps to complete the picture of what is happening in the water around these islands. The tow team (Ben’s team) circles the islands in a small boat, towing two divers behind them at 1-2mph and 5-10’ above the bottom. These divers are able to cover a much larger area than someone free swimming, photograph/video the bottom, and count the large fish (greater than 18”). There are not that many large fish living close to the reef, so to get an idea of their population size, it is necessary to cover larger areas. All of this data is generally used to monitor the state of the reefs, not restore them. However other agencies use our data to launch restoration projects and make decisions about how to manage their reefs. For example, after the governor of Samoa learned that the amount of large fish around Samoa, a heavily populated area, was much lower than around other islands in Pacific, he proposed closing the fishery for large fishes. On the other hand, when the governor of the Commonwealth of the Northern Marianas Islands found that large fish generally remained only around the most remote northern islands, he proposed holding a fishing tournament there. So unfortunately we can’t control how our data is used, but some good does come of it. The decisions to create the Northern Hawaiian Islands and the Pacific Remote Island Areas Marine National Monuments were both based largely on data that CRED has collected through the years.

I hope this helps in understanding what it is we do out here.

Take care and goodnight,
Cristi