How are things?
BUSY!!!! I think that might be the best way to sum things up so far. I left Corvallis on June 13th, traveled all night and the next day to get out here to Lee Stocking Island home of the Perry Institute for Marine Science (perryinstitute.org) and we started work first thing the next morning. This place has a lot of awesome history as a field station particularly for our team. Dr. Hixon started coming here in 1990, only a couple years after it opened. Since that time all of his PhD students have completed the field components of their research in the water around the area. There are a lot of different study sites throughout the island chain that we have been visiting sporadically. In the early 90s Hixon built a big grid of artificial reefs (4 foot x 3 foot x 3 foot blocks of cinderblocks) and transplanted reefs(made of real live coral heads) to make a big experimental setup within this big seagrass bed. This is where most of the work for the project I am working on has taken place. They are really amazing now after nearly 20 years of growth. The artificial reefs are coated in corals and big sponges and have all kinds of encrusting organisms on them. Aside from the network of holes running through them it can be easy to forget they are cinderblock. The transplanted reffs have grown into tiny communities with recruit fish(babies), grazers, and big predators. Some have experienced bleaching events along with the corals in the area and are very much a part of the system.
We started the first day with baseline censuses of every type of fish and a few key invertebrate species that were living on every reef. It was quite the learning curve to splash down onto a trans-reef the first time with a slate and be expected to be able to name, count, and size all the fish swarming in front of me. There are about 20-25 species we see consistently across all the sites and then others that appear just when their name has slipped out of your head. After the first few days I was feeling pretty confident and even helped the interns who dive with us pick up a few of the common species. It's a little funny because most people know fish by common name, but they are on our slates by scientific name. And to complicate matters further... we use a code abbreviation of each species (first two letters of the genus and first two letters of the species). An Example: Stegastes partitus- the dusky damselfish (a cocky little fish that will bite at your fingers or mask when you get too close to its home of a hole in the rock) is known as STPA. Most of the fish have divergent color patterns as juveniles and adults so that throws a bit of a wrench into things. STPA is bright yellow with a blue dorsal fin and stripe along its margin with a black dot as a juvenile. It is blue/brown/black/browish as an adult with no easily identifiable dots or lines. It's been lots of fun and certainly kept my mind busy with staring at fish all day then staring at a fish ID book all evening.
After all the initial censuses were completed we created our experimental design with all the treatments- with lionfish, without lionfish, with two lionfish, with one native predator, with two native predators, or with one native predator and one lionfish. The work began shuffling fish around the reefs until we had them just right. Undoubtedly, upon returning the next day fish would be missing and we would have to catch, measure, weigh, and place new fish on. After a week or so of shuffling the experimental design changed, simplified in some aspects and expanded in others, and we started over again with a new plan. Five blocks of reefs have now been set up and had an initial census (a three day process) of the recruits present there. Tomorrow I am headed out again to be sure all fish are where they are supposed to be. Cross your fingers they have all stuck on their reefs! Plenty of work for the rest of the week if they have shuffled.
We have been working about 15-17 hour days, seven days a week since arriving here. The reall cool thing is that I am getting to be in the water diving for nearly 8 hours everyday. The transreefs where our experimental set-up lives is very shallow so a lot of my diving has been under 10-15 feet. The current can scream through at some of them when you're lined up just right with the channels in between islands. The water off the Great Bahamian Bank rushes off through our site and out into Exuma Sound every day with the tides. That's a big part of what makes this such a unique area. On one side of the island is Exuma Sound- an large oval body of water thousands of feet deep surrounded by little keys. On the other side, is the Bahamian Bank which might be 20 feet deep or less for hundreds of miles. There is huge nutrient flow and tidal flow (not in height- but the fact all this water sitting on top of the big flat shallow sandbar flows on and off everyday) between these bodies of water and their interaction creates some really nice habitat in the area.
In the picture you can see the dark deep water to the right of the island and the shallow sand bars off to the left. I'll try to find one less zoomed in so you can get the bigger picture.
What am I doing?
The Indo-Pacific lionfish got introduced to the Bahamas in the 1990s with a little debate about the number of introduction events and exactly who did it. It's known that Hurricane Andrew destroyed a small aquarium with 6 in it in South Florida and a few months later the first sightings were recorded in the same area. Seems pretty straight forward to me. Since that time they have spread all throughout the Caribbean eating fish like crazy all along the way. Sightings have spread as far north as Rhode Island and as far south as the French Antilles. Here at LSI the first sighting was by our team in 2005- 1 lionfish. 2006- 2 lionfish, 2007- 107 lionfish, this summer we have found 157 so far in the first three weeks. It is by far the closest thing to exponential growth I have ever seen. This is the really pretty red and white or black and white fish with the big pectoral fins and the venomous dorsal spines. They are totally gorgeous, just really badly invasive in this area.
The study from last summer found that a single lionfish on one of the trans-reefs could reduce recruitment (survival of baby fish) by 79% in 5 weeks. This is major bad news bears for the endemic reef fish! This summer I am assisting Mark Albins in looking at the relative effects of lionfish versus other natural predators in the area. We want to see if lionfish are having a much more profound effect than the fish normally found preying on little fish in the area.I will also be doing my own research project down here, thanks to winning a grant from Howard Hewes Medical Institute, which is pretty sweet! I am working on pulling together an experiemental design right now but it looks like I will be working on the feeding preference of lionfish (which baby fish are most tasty) and also working with some native predators, particularly large Nassau grouper, to see if they will prey on lionfish as a potential means of population control. Conversely I think I will also see if lionfish are preying on young Nassau since this is a very important fishery and conservation species in the region. It's all very exciting to get to do my own work on the topic and I am sure I will be posting lots more when I know more.
As we did the census of reefs we removed all the lionfish when we found them back to aquaria on the island. Naturally we had to give them names, and with a little help from Tim decided on superheroes as the theme for this year. Last year they started out as reggae artists, which swiftly became naming them gangsta rappers. Hard to beat a theme like that, but superheroes is a good effort. I gladly welcome suggestions since realizing I was never really a kid who followed super heroes too closely. Some of our heroes have been delivered back to the reefs they came from to serve as treatments in the experiment and I hope they are out there happily munching away on recruits as I type.
I'll continue to play catch up on the events of the last couple weeks as I can, although I'm getting a little bleary eyed from the blogging right now. I hope you all are having a fantastic Tuesday and smiling lots!
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