By: Aimee and Laura
With coming out to the Cook Islands, we were excited to conduct a new type of research. This excitement was blinded by the difficulties that come along with marine research. After being split into our teams these specific challenges started showing.
Today, the reef team conducted research on the lagoon near the airport and out in front of the Pacific Resort. 10 meter transects were laid out with one person surveying for invertebrates and two others measuring the coral height and species. We faced many challenges today, in the morning there was cloud cover and it was a bit breezy. The team was dressed in wetsuits, but we all were freezing. Though cold, we managed to stay in the water for three hours and finished the transects. Another problem was that the water was very turbid, which made it hard to spot and identify species. The turbidity, along with recently learning the specific species identifications, made our first transect take the most time. By the fourth transect we were well on our way at identifying coral and fish.
The Night Snorkel
Tonight we snorkeled north of where we are staying. The snorkel site is considered to be one of the best on the island. The night was beautiful for snorkeling while the full moon lit the water. Our flashlights led our way into the lagoon where the floor was littered with sea cucumbers and purple starfish. As we swam further into the lagoon we came across coral with their polyps out. We saw some fish that are common during the day like the convict tang hiding in the coral. We also saw cardinal fish that took the place of damsel fish during the night. Another exciting spot was the squirrel fish that was reddish with big eyes. Snorkeling at night was drastically different from during the day. There were more translucent fish out during the night and overall the fish species out at night were different from during the day. The different day time and night time species shared similar niches but were out at opposite times during the day making it possible for both types to survive.
The reef team has the role of surveying coral reefs as one aspect of the entire research project. Surveying coral reefs includes studying fish species, corals, algae, and invertebrates. The protocol is done in four 10 meter transects per site. First the fish expert swims through the transect counting and identifying all the fish in a two meter width along the transect tape. After all the fish are counted, the person identifying and counting invertebrates swims through. This person swims five meters counts and identifies two meters wide then the transect by doing the remaining five meters. Then the person identifying invertebrates within the transect goes next and measures the height of the coral at each meter mark along the transect. The last team member identifies the substrate which includes corals, algae, rocks or other matter that might be on the ocean floor.
Comparing both days of conducting reef research is interesting. The first day posed multiple challenges. There was poor visibility and the tide was going out making the site very shallow. Today the visibility was great and the water was deeper. The only challenge today was the strong current. There was also a much higher biodiversity among invertebrates on the first day most notably the amount of sea cucumbers. There were a lot of sea cucumbers at the site surveyed on the first day and less sea cucumbers on today’s sites. However, there were more Giant Clams, Trochus snails, vermetid snails, and sea stars. The coral was different from the first day. There was less acropora and pocillopora and more porites. Tomorrow we will go back to one of the sites of the first day and another new site. Cannot wait to see what is in store next.