For the past two days I have been working on the lionfish team instead of the aquaculture team on field data collection. Yesterday was pretty nasty, windy and rainy to make a windchill of around 65, and I forgot to wear my wetsuit to it turned out to be pretty miserable, but today was sunnier and warmer.
The dives take place on patch reef ecosystems, little islands of coral in a sea of sand and turtle grass. The bay we were in, Rock Sound, had a max depth of 11 feet, so dives were very shallow, but I was able to stay down longer and use less air because of the lessened water pressure. The area surrounding the patch reefs are prairies of sand and turtle grass browsed upon by herds of foot long sea cucumbers, and the reefs themselves vary in size, but almost all are the size of a large room. After having dove at the Cobia cage, which is near a 1,000 foot wall, I can definitely see a difference in fish and coral cover, the patch reefs having more juvenile fishes while the area around the cage has lots of big fish.
We spend about 30 min at each site, with the goal of surveying 6 sites a day. Transect lines are set up crisscrossing the reef, and some of the other interns follow these lines and try to count and identify all the fish species they see in an attempt to quantify the effect lionfish are having on fish biodiversity. My job was to find lionfish hiding in the nooks and crannies in the reef and measure their length while trying to not get stung. Over the 6 dives I counted lionfish, I counted 58 lionfish, but there were more than 100 on these reefs when one factors in dives I did not participate in. Considering their veracity and high place in the food change, the reefs are ravaged of small fish populations, especially gobies and juvenile wrasses which were nonexistent at several of the reefs. Overall the reefs are changing dramatically in their fish biodiversity and biomass as we compare fish population data pre lionfish invasion.