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Day 6: 4.25.06
Stable Isotope Collections
fish for stable isotope analysis,
by A. Poray)
Stable isotope analysis is a tool used to examine the trophic (feeding) linkages between plants and animals in an ecosystem through examination of carbon and nitrogen levels across the food web. Piscivorous (fish-eating), herbivorous (plant-eating), and planktivorous (plankton-eating) fish as well as various species of invertebrates and algae are being collected on this research cruise as representatives of Navassa’s complex food web. Isotope analysis will provide us with a better understanding of the movement of energy from the primary producers (such as photosynthetic plants and plankton) to the top consumers (such as fish) for the communities associated with Navassa Island.
For samples to be analyzed using stable isotopes, the science crew collects fish, coral, and algae specimens based on a predetermined species list. This kind of collection at Navassa Island National Wildlife Refuge is allowed by the permit from the US Fish and Wildlife Service. Species collection is cautiously balanced between the abundance and availability of each desired species and the sample priority list.
- Fish collections may be by trawl, hook and line, or by spearfishing. (
- For coral sample collection, divers carefully take only a small sample of tissue, about the size of a quarter, off the edge of a colony with a chisel and hammer.
- Clumps of macroalgae are hand-collected by divers.
All specimens collected are preserved in a deep freezer aboard the Nancy Foster for future analysis back at the lab. There, muscle tissue is removed from fish, dried, and ground for analysis in a mass spectrometer.
Habitat and Fish Surveys
Fair seas during the last two days have allowed us to dive on the east side of the island. This windward side of the island can often be inaccessible because of the trade winds and potentially large waves. Both of today’s habitat and fish survey dives were in approximately 100 feet of water on a pavement-like hardbottom. Although this area does not have the large rock features of some of our previous sites, it still provides valuable habitat to a variety of fishes and invertebrates. We have observed fish species such as large French angelfish, bicolor coneys, and soapfish.
 Large
flower cup coral (Eusmilia fastigiata) surrounded by sponges. Photo
by S. Moneysmith |
 Brown
boobies interested in the radio antenna on a small boat. Photo
by A. Uhrin |
Scientists in the spotlight
The dive team self-titled "The Chorbitas" are just one example of the extensive interagency cooperation evident in the scientific party. Photo: Divers J. VanderPluym (front) and C. Addison enjoying their safety stop at the end of their dive, by S. Moneysmith
Shelby Moneysmith is the team habitat photographer. Shelby is a Biological Science Technician and the Dive Safety Officer (DSO) for Biscayne National Park, in Homestead, FL, where she is a valuable contributor to a variety of ongoing natural and cultural resource management projects. We are fortunate to have Shelby’s positive attitude and superior dive skills on this, her first offshore research cruise. Photographer extraordinaire, S. Moneysmith, making a rare appearance in front of the camera, by C. Addison
Jenny VanderPluym, research technician, departed on the Navassa cruise just one week after starting at CCFHR. Jenny’s main duties on the cruise are counting fish as a scientific diver and writing website copy. In March, Jenny completed her master’s degree in marine science at North Carolina State University. Photo by S. Moneysmith
Christine Addison, biological technician at CCFHR, is a fish counter and Principal Investigator for the conch survey. Christine has enjoyed the exploration of such a remote, tropical location with its rich marine and terrestrial wildlife and has been an avid bird watcher between dive operations. Christine will be pursuing a master of marine science degree at the University of California, Santa Barbara this fall. Photo of Shelby Moneysmith (L) and Christine Addison (R) by J. VanderPluym.
Spotlight on Crew members
Tom Cleary, Third Engineer
“I’m from Cape Cod originally,” says Tom with an accent to make any Massachusetts native proud. He began working on the water as a mate while a teenager and continued as a ferry boat captain (100 ton license) even after graduating with a double major in History and Political Science from Elon University, in Burlington, NC. After applying to NOAA, he was offered a job in the engineering department and jumped at the chance to work from one of his favorite ports of call, Charleston, S.C. Tom has worked with NOAA for five years and has been on the Nancy Foster for one year. Although he misses his wife and two children, he loves the engineering work and enjoys the Foster crew.
Tom's daily duties include:
- engine room watch
- continuous engine maintenance
- small vessel maintenance
- large machinery repair
- maintaining the many electrical and plumbing systems of the Nancy Foster
Photo by J. VanderPluym
Will Wells, NOAA Corps Navigational Officer
Will entered the NOAA Corps directly after graduating from the University of North Carolina, Asheville with a major in atmospheric science. The 25 year old North Carolina native will complete his entire at-sea assignment on the Nancy Foster and couldn’t be happier about it: “I can honestly say I work with one of the best crews in the fleet.” He enjoys the diversity of projects this ship takes part in: coral habitat classification, multi-beam operations, whale watching, and water quality sampling after Hurricane’s Rita and Katrina. After completing his at-sea assignment, he will move to the National Data Buoy Center in the Stennis Space Center in Mississippi.
Will's daily duties include:
- updating navigational charts
- correcting coast pilots (NOAA publications that detail points of interest in the area)
- maintaining navigational publications
- maintaining navigational instruments
- standing watch and driving the Nancy Foster
- operating small vessels.
Photo by J. VanderPluym
Brad Delinski, Acting Boatswain Group Leader
Brad has worked at sea for the last 10 years, making port in 27 different countries. Perhaps this was because of spending his first 10 years in the landlocked desert of Arizona. Brad, 30, initially gained valuable ship experience during eight years as an Army Quartermaster on a 130 foot ocean tug. In the three years that Brad has been with NOAA, he has worked on three NOAA ships: the Rude, the Ronald H. Brown, and the Nancy Foster, where he's been since July 2005. Brad has been promoted from Ordinary Seaman to Group Leader, which requires him to be a master at multi-tasking.
Brad's responsibilities include:
- launching and recovering small boats
- standing bridge watch
- maintaining boats and deck equipment
- operating all deck machinery
- directly assisting the Chief Boatswain
- being a diver, dive medic and medical person in charge (MPIC)
Brad’s future plan is to get his Mate’s license and work on the bridge. He makes this comment about his demanding job: “people pay to go on vacation, where we are paid to go to work›the view from my office window is never the same twice.” Photo by J. VanderPluym