The Big Take-Away
- Coral reef health
- Goliath grouper feeding behavior
- Barrel sponges
- Environmental contamination
Principal researchers: Mark Patterson, Brian Helmuth, and Loretta Fernandez
Graduate students: Amanda Dwyer, Alli Matzelle, Jessica Torossian, and Nick Colvard
Technicians: Francis Choi and Sara Williams
Media and Outreach coordinators: Morgan Helmuth, Amanda Padoan, Angela Herring, Ursula August, and Kara Sassone
The Science Details
Coral Reef Health
Our research will help answer: How do corals respond internally to daily fluctuations in external temperature, light, pH, and dissolved oxygen? The topside team will insert Unisense electrodes into three coral polyps per colony underwater to measure the gastrovascular system (the gut) of the corals. Data collected 24/7 over two weeks, creating the first long-term data set from wild corals. In addition to the data from the electrodes, Liz and I will measure corals' photosynthetic performance with a PAM fluorometer.
We'll record unique predatory behavior of the goliath grouper using a state-of-the-art high-speed Edgertronic camera. The results could validate the unproven theory that Goliath Groupers use the sound of a collapsing cavitation bubble formed in their head as a weapon to stun their prey. It'll help answer: What is happening during a grouper's feeding strike, and does the grouper use sound as a weapon?
Every day we'll collect small samples of zooplankton with nets to quantify their presence on the reef. The data will help scientists answer: How are plankton communities changing with climate change? In addition, the ratio of alive to "zoombie" (recently dead, but not broken down or consumed yet) zooplankton in our samples will give insight into the populations and lifespans of these creatures, which are necessary for coral reefs to be resilient against coral bleaching events.
Sponges are prodigious filter feeders. They filter water equal to their entire body volume in less than a minute and remove more than 99% of the particles they inhale, most of which are bacteria. Part of the reason visibility is so good on a coral reef is becuase of the filtering by sponges. We are looking to answer the following research questions: How do barrel sponges filter material and how can we model their behavior? Does their behavior fluctuate over the course of a day in a predictable pattern (circadian rhythm)? Are neighboring sponges pumping at the same rate or is every sponge different? We'll answer these questions using sensors that measure fluctuations in temperature, salinity, pH, dissolved oxygen, and flow over the seafloor and in the water coming out of the sponges. From these measurements, the Northeastern researchers can study how sponges' metabolism and feeding rate respond to changes in the environment. We'll also collect DNA from 14 different sponges for the Ocean Genome Legacy Project.
We'll deploy and recover sensors that absorb and measure environmental contaminants, including PCBs, PAHs, and potentially dispersants from the BP oil spill. They will help us answer: What environmental contaminants are in the coral reef? Based on the findings, Dr. Loretta Fernandez can model contaminants in the area and refine methods for measuring them.
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