How I spent my summer vacation...

Just got back from a summer filled with traveling- for work of course! I spent almost 3 weeks in Panama at the Smithsonian Tropical Research Station in Bocas del Toro where I took a Sponge Taxonomy and Ecology course. Dr. Cristina Diaz and Dr. Bob Thacker, two experts in the sponge field, taught the course to a group of 12 students from all over the world. It was an intense course, however the long days in the water and the lab were all worth it! I learned some very valuable tools that will help me to complete my PhD project. Which brings me to my next travel destination- Jamaica!

Sponge spicules through a microscope. Each sponge species has a unique set of spicules, defined by different shapes and sizes. By looking at the spicules (what gives the sponge its structure) under a microscope you can identify the sponge species.

For the last 2 years I have been traveling to Jamaica every six months to study the effects of sediment on the coral reef ecosystem. The northern coast of Jamaica, unlike the southern and western coasts, is naturally very rocky. Tourism in Jamaica is expanding, and to accommodate the increased demand, large mega-resorts are being built. Resorts with over 10,000 rooms are a common sight along the north coast of Jamaica! And what do tourists want on their tropical vacations? Sand and sun. The problem is that these hotels must create artificial beaches since the coast is rocky and very few natural beaches occur there. So hotels and resorts buy sand and fill in the coastline surrounding their properties, creating beaches. However, since the northern part of Jamaica is the windward side of the island, the waves are constantly eroding the ‘beaches.’ This creates a sediment problem for the adjacent reef, as some of the fine-grained sand and silt gets washed out onto the reef organisms.

Reef organisms often have a difficult time dealing with sediment since many of them rely on filtering large amount of water to eat and if there is lots of sediment mixed in with the water it can clog their filtering mechanisms. Sponges in particular filter large amounts of water to obtain enough food to live. When there is a large amount of sediment in the water some sponges respond by shutting down filtering or slowing down and reducing the amount of water they process. This means that they are getting less nutritionally, and may suffer in the long term. My project involves looking at the cost of the sediment stress on sponges. I am looking at several aspects of sponge ecology- growth, recruitment, diversity and abundance, to help gauge what effects the sediment may be having on sponges in Jamaica.

For my project I visit the Discovery Bay Marine Lab in Jamaica every August and January. I have an ongoing settlement plate experiment to look at what organisms (including but not limited to sponges) are settling and growing into juveniles. Each plate is out on the reef for 6 months. I have plates at 3 different sites, and each site is divided into two depths. Each site represents a different level of sedimentation: low, intermediate and high.

One of my plates after being in the water for 6 months.

This last trip I was removing the old plates (which I put out in January), photographing them, and replacing them with new plates that will be collected in Jan 2011. For each plate I photograph both the top and the bottom and then bring them back to the lab and take samples of organisms that I cannot easily identify. In addition to replacing the tiles, we wrapped up the diversity and abundance surveys. In total we completed 60 surveys where we measured and identified every sponge we saw. A total of 65 species were positively identified and 4067 individual sponges were measured!

Overall, it was a very successful trip!