NOAA Teacher at Sea
Tara Treichel
Onboard NOAA Ship Nancy Foster April 15-27, 2008
Mission: Lionfish Survey Geographical Area: Atlantic Ocean, off the coast of North Carolina Date: April 27, 2008
Weather data from the bridge
Visibility: 10 n.m.
Wind: 11 knots
Waves: 1-2 feet
Ocean swells: 3-4 feet
Sea temperature: 23.0
Air temperature: 23.0
At 120 feet, the water has absorbed red, yellow and green wavelengths of light, muting the brilliant colors of these Lionfish and other reef organisms (the Lionfish in the foreground is partially illuminated by the video camera)
Science and Technology Log
I wanted to explain a little more about the purpose of the Lionfish study. The technical name of the study is Assessment of Lionfish Ecosystem and Fisheries Impacts. The Principal Investigator/Chief Scientist is Paula Whitfield, who works out of the NOAA Lab in Beaufort, North Carolina. Several years ago, Paula had heard reports of Lionfish seen off the coast of North Carolina. A recreational diver, Paula visited these sites to see for herself; what began as a casual observation turned into the guiding question for a complex Lionfish ecosystem study that is now in its seventh year. As I understand, the guiding questions framing the study are:
Initially the scientists needed to understand, to what extent Lionfish have invaded the coastal waters of the eastern US. Under this broad question fall many sub-questions: Are they successfully reproducing? How large is their population? Are they expanding their geographic range, and is their population growing? Finally, what biological and physical factors may limit their survival (i.e. what environmental conditions do they need to survive)?
After the initial research results revealed a widespread and well-established presence of Lionfish, researchers refined their objectives to better understand the fisheries and ecosystem impact of Lionfish. This is a very broad question and includes many sub-questions such as: What species are they eating? Is the number of “conspicuous fish” species (large and easy to see and count) decreasing in areas where Lionfish are present? Are the number of “cryptic fish” species (small typically prey species that hide within the habitat) decreasing in areas where Lionfish are present?
The scientists also seek to better understand how Lionfish impacts may be further complicated by other variables such as overfishing and climate change. Examining this question requires looking at many other aspects of the marine ecosystem as indicators of ecological health. Sub-questions are: How are the physical and chemical ocean parameters changing over time (e.g. sea temperature, ocean currents, chemical composition)? How are algal populations changing over time? How are invertebrate and soft-bottom communities changing over time?
Initial results of the study were eye-opening. Everywhere the research team went, they found Lionfish. From 20042007, the data across the sampling sites showed an increase in population of well over 300%. Considering that these fish have no known predators, and females release 30,000 eggs at a time, it is not hard to imagine the severe impact that these fish could potentially have on the marine food web and ecosystem. In addition, Lionfish are tropical reef fish, which require warm water to survive and reproduce. As climate change occurs, it is conceivable that Lionfish could expand their range in response to rising sea temperatures or a shift in Gulf Stream currents.
Paula Whitfield (right), Chief Scientist of the study, and I enjoy the sunshine.
NOAA Teacher at Sea
Tara Treichel
Onboard NOAA Ship Nancy Foster April 15-27, 2008
Mission: Lionfish Survey Geographical Area: Atlantic Ocean, off the coast of North Carolina Date: April 26, 2008
One of the Survey Technicians operates the Multi-Beaming mapping system.
Weather Data from the Bridge
Visibility: 10 n.m.
Wind: 11 knots
Waves: 1-2 feet
Ocean swells: 2-4 feet
Sea temperature: 23.5
Air temperature: 22.0
Science and Technology Log
In addition to the Lionfish survey, the other research that is being conducted while aboard the NANCY FOSTER is benthic habitat mapping of the ocean floor. This is accomplished using highly sophisticated, computerized multi-beam SONAR technology. Two survey technicians aboard the ship are responsible for running and monitoring the system, which is run all through the night. The operators make sure that the system is recording data properly and that the ship stays on course (within about 5 meters), and process the data as it is recorded. The course is set and followed, lawnmower style, back and forth along long narrow parallel lines, producing a beautiful rainbow colored map coded for “depth by color,” where red is high and blue is low. After five nights of mapping, the white digital nautical chart contains five tiny rainbow swatches, each one representing about 10 square miles of mapped space. Each year the research team adds to the swatches, until one day perhaps the entire bay floor will be mapped. Scientists later use the maps to support their research; in this case, Paula used them to determine where to dive. With countless miles of ocean floor (much of which is sand, or poor fish habitat) and limited time and research budgets, the maps are a critical part of the research effort.
Tara holds up a specimen that some of the scientists said was the biggest Spiny Lobster they had ever seen!
There are a lot of variables such as temperature and salinity that can influence the transmission of the sound waves produced by the multi-beam sonar to measure seafloor depth. In order for the data to be as accurate as possible the survey technicians need to measure these variables throughout the water column using a CTD (conductivity (salinity), temperature and depth). They conduct three CTD ‘casts’ a night by first lowing and raising the CTD on a long cable that is controlled by a winch.
Personal log
Today, the Chief Engineer caught a Wahoo off the stern of the boat. Wahoo! Can you think of a fish with a cooler name? It’s a cool fish, too, sleek and streamlined, with large jaws and a loud stripy pattern on blue gray skin. It was perfect timing, since a barbeque was planned for our last afternoon at sea. The fish is nearly all muscle, and yielded 25 steaks, almost enough for each one of our full ship of 35 people aboard. How was it, you ask? Delicious! The scientists also caught several large Spiny Lobsters, a Scamp (a Grouper), Hogfish, Sea Bass, and of course, many Lionfish. In addition, they saw a Mola Mola (Sunfish) and several Loggerhead Turtles.
NOAA Teacher at Sea
Tara Treichel
Onboard NOAA Ship Nancy Foster April 15-27, 2008
Mission: Lionfish Survey Geographical Area: Atlantic Ocean, off the coast of North Carolina Date: April 25, 2008
The diver support boat NF-4 waits for the dive team to surface.
Weather Data from the Bridge
Visibility: 10 n.m.
Wind: 2 knots
Waves: 1 foot
Ocean swells: 2-3 feet
Sea surface temperature: 23.4
Air temperature: 21.5
Science and Technology Log
Today the morning dive at Lobster Rocks went to 125 feet. The report was that it was an excellent dive, and the video showed this to be true. The visibility was excellent and the habitat looked rich. Among the Amberjacks, Grouper, Blue Angelfish, and Hogfish, were tons of Lionfish! They were everywhere, lurking around every ledge and rock. They look like princes of their domain, regal in their showy capes of red and white, brandishing lances to keep out intruders. Neither aggressive nor fearful, as they have few if any predators, they hover in place, guarding their territory from other lionfish.
NOAA Teacher at Sea, Tara Treichel, has just taken length and fin ray measurements from this large lionfish, and has removed gonads and a gill sample for lab analysis.
The morning divers brought a small collection of creatures back for further study, including a sample of bryozoans (a form of attached invertebrates that looks a lot like algae), a large spiny lobster (carapace at least 5 inches in diameter), a handful of fish for the cryptic fish survey, and about a dozen Lionfish. I helped Wilson take basic measurements from the Lionfish, and dissected them to remove gonads and gill samples for DNA analysis. The fish ranged in size from 150 to 380 mm, from mouth to end of tail. Next, dorsal and anal fin rays are counted, to help determine species classification (lionfish are of Indo-Pacific origin, and are classed in two subspecies based on number of fin rays). On the fish sampled, dorsal fin rays varied between 10 and 11.5, but anal fin rays consistently numbered 7.5. After I had removed the gill section and gonads, I gave the fish to Brian, who opened up their stomachs to take a cursory look at what the fish had been eating. In one, he found a small spiral shell about the size of a shirt button. In another, the stomach was bulging full, and contained four small fish, whole but partially digested and terribly stinky. All in a day’s work of a scientist! After this initial information was collected, the fish were labeled in zip-lock bags and frozen for later study.
The stomach of this small Lionfish contained four partially digested whole fish.
Personal log
Today I had the fortune—and the misfortune—of getting out in one of the small boats. I say fortune because the conditions were ideal: calm seas and sunny blue skies. It was a great day to be out on the water, and I expressed an interest in going for a swim. We were responsible for shuttling the safety diver to assist the dive team, and transporting the dive team back to the NANCY FOSTER. The misfortune occurred toward the end of the dive, as the safety diver was trying to reboard the boat. To make it easier for him to enter the boat, the skipper removed the side door of the craft, a routine task. Under normal circumstances, the bilge pumps purge any water that splashes into the boat, but on this day, for reasons unknown the bilge was already full of water, and the water that surged into the open door space quickly filled the stern of the boat. We tried to replace the door, but the water was spilling in too quickly, and the boat slowly overturned. So, I got my wish to swim faster than I’d expected! Fortunately, as I mentioned, it was a fine day for a swim. Minutes later, two rescue boats were deployed from the NANCY FOSTER, and shortly after we picked up the dive team and were safely onboard the mother ship again. The ship had quite a challenge getting the overturned boat back onboard and into its cradle, but with skilled use of the crane, the boat was recovered in little over an hour. It was the sort of adventure I had least expected when going out to sea. I was happy that no one got hurt, and impressed with the response of the NANCY FOSTER crew.
NOAA Teacher at Sea
Tara Treichel
Onboard NOAA Ship Nancy Foster April 15-27, 2008
Mission: Lionfish Survey Geographical Area: Atlantic Ocean, off the coast of North Carolina Date: April 24, 2008
Weather Data from the Bridge
Visibility: 10 n.m.
Wind: 7 knots
Waves: 2-3 feet
Ocean swells: 3-5 feet
Sea surface temperature: 24.5
Air temperature: 23
NOAA Divers at the rail of the ship just before a dive
Science and Technology Log
Today the NANCY FOSTER deployed four dive teams, two each at two survey sites. This is a tricky maneuver, requiring the coordination of many people. Preparations included an hour-long briefing of the plan and review of safety information, in which divers were reminded, among other things, to stay close to their buddies since an “out of air” emergency could spell the end of future diving opportunities with NOAA. On the deck, the chaos was well managed. With extensive use of hand-held 2-way radios, communication was maintained between the bridge (control station of the NANCY FOSTER), the two small boats, and the deck support: the two small boats were launched with the aid of the crane, and the mother ship was jockeyed into position alongside the dive site target buoys that had been dropped earlier. When the position was just right, the call was made, “Divers to the rail,” and the four divers, weighed down by double layers of wetsuit, twin tanks, dive computers, and mesh bags holding notepads and pencils, were lead to the edge of the boat. One by one, they stepped off the boat and disappeared beneath the surface, leaving a trail of bubbles to mark their descent.
The divers will visit sites that were selected years ago when the lionfish study first began. The sites were chosen using benthic maps of the ocean floor to help identify favorable fish habitat. Today’s dives were at “WOO6” and “Big Fish”, in 130 and 150 feet respectively. These depths are beyond my PADI Open Water limit of 90 feet, and require mixed Nitrox gas in order to extend the underwater dive time. Use of mixed gas at these depths qualifies this as “technical diving” and involves an increased risk to the divers, so the NOAA lab has contracted with NURF (National Underwater Research Foundation) to provide technical dive support. Divers have strict bottom time limits and must make several safety stops on their ascent; in addition, a Hyperlite recompression tank stands at ready for any nitrogen sickness emergencies (“the bends”). During the dives, the researchers do a variety of tasks. All of the researchers take general habitat notes, and record the presence of marine debris. Paula and Brian are surveying the large, “conspicuous” fish, including lionfish, by estimating the population size of each species along a given transect length. Paula also will collect a temperature logger that she placed at the site 1 year ago, which has recorded temperature data every half hour. Roldan and Christine are surveying “cryptic” fish communities (prey species that are very small or that hide within the habitat). Roldan lays out a one-meter square PVC quadrate and chemically stuns and collects the fish, which he then captures in a Ziploc bag for later study. Wilson is studying the algal community, but finds that there is very little to collect this early in the season. He also spears a number of lionfish for later study, which he bags carefully to avoid being stung by the venomous spines. Finally, Thor and Doug alternate between video camera duties, documenting the underwater habitat.
NOAA Ship NANCY FOSTER as seen from the divers’ support boat
Personal log
First impressions, and notes on the boat: The ship is due into port at 1700, and it is right on time. After the events of the past week, this is a pleasant surprise. I am struck by the size of the ship. It is massive and bulky, with a flared steel bow that towers over me as I watch from the pier. Quite unlike the nautical parallel parking that I learned as a teenager growing up on a northern Wisconsin lake, this ship is equipped with side thrusters that allow it to maneuver its bulk with some amount of precision. Immediately, I can see that understanding momentum is a key factor in handling this boat: the ship is anything but “quick on its feet” when a change in direction is needed, and lack of planning for this fact could be disastrous. But today is not the day for a demonstration of this lesson. After 20 minutes of adjustments, the two-inch deck lines are thrown out from the ship, and it is securely tied to rest for the night.
A flurry of activity ensues. There is excitement in the air, like the charge before an electrical storm. The outgoing crew is anxious to be on home turf again, after weeks away at sea and in foreign ports, and the new team of scientists is equally anxious to get underway and begin their mission. The wind adds to the fervor, whipping my hair across my face and sending the Stars-n-Stripes cracking over the stern of the ship. The gang plank is lowered into position by the lower deck crane and a cargo net is secured below. For the next 10 minutes, there is a steady flow of bodies and boxes, as mail is shipped onboard and supplies from the previous mission are offloaded. A deck crane is used to hoist crates of heavy equipment on board, including dozens of SCUBA tanks.
Loading the scientists’ equipment onto the FOSTER using the ship’s deck crane
The NANCY FOSTER is an oceanographic research vessel of the NOAA fleet. One hundred eighty feet on deck and built of steel, she is made for ocean navigation and equipped for scientific research. She was built in 1986 by the Navy as a torpedo tester, and is considered very seaworthy. Throughout the year, she is used for a variety of scientific research missions, each research team outfitting the boat with its own specific technical equipment. Two onboard labs are designated for this purpose: a dry lab, housing numerous computer stations and data processing equipment kept dry (and frigid) with continuous air conditioning. All told, including mine, there are 16 computers in this room. One wall holds 7 flat-screen monitors, one of which displays a live video stream of the stern decks of the ship, where at the present moment a hopeful engineer is dragging a fishing line through the rolling blue waves. Adjacent to the dry lab is the wet lab, mostly an empty room that quickly fills with scientists’ tools of the trade: bins, underwater cameras, measuring devices, dissecting equipment and specimen preservation chemicals, and bags upon bags of SCUBA gear. In the wet lab, I get my first glimpse of our quarry, and the purpose of the mission: numerous copies of fish identification books adorn the tables, and the walls are full of color posters depicting creatures of the deep—echinoderms, manatees, Caribbean reef fishes.
Looking around the ship, one can’t help but notice the references to danger. All around are reminders of things that could go wrong (and undoubtedly have). Most noticeable is the large red motorized rescue craft hanging from the mid deck crane. Next to it is a green painted stamp indicating an emergency meeting or “muster” area. To the left of this is a coiled canvas fire hose, with the stamp “No Smoking” printed above (elsewhere, crew are instructed to smoke aft of the rear crane, preferably “away from the gasoline cans” and where the SCUBA oxygen bottles are being filled). Across the deck from the fire hose is a closet holding 10 Immersion Suits, 5 medium and 5 large, as well as 15 life jackets. Around the corner are three oversized barrels containing full immersion survival gear, including 25 person life rafts. Down the railing from the barrels and placed all throughout the ship in various conspicuous places are the timeless classic orange life-rings printed with the ship’s name in black blocky script. Inside the boat, there are more reminders: emergency procedures, the ship’s interior plan depicting the location of every rescue device and exit onboard, and numerous posters outlining CPR in simple steps and photographs. I would not want to have an emergency on board this ship, but if the unthinkable happened, I am confident that this ship and crew are well prepared.
I am led through watertight doors and down a narrow flight of stairs into the belly of the beast, on the first floor of the ship. My berth is in Stateroom 17, which sleeps four, in bunks containing mattresses that give a whole new definition to the size “single”. I choose a top bunk, which gives me a little more head room amidst the crisscross of pipes overhead. I am instructed to unload everything into the closets and cabinets that line the walls, since everything that’s not strapped down or contained in a box will be subject to repositioning by the motion of the ship. And motion there is! As soon as we get out of the harbor and away from shore, the 4-5 foot waves set the boat into an irregular pattern of constant swaying from side to side as well as front to back, like a rocking horse on a swivel. I won’t elaborate on the effects of this motion on my body and mental state, since seasickness has been well described elsewhere. Suffice to say that the benefit of the tiny pink pills can’t be overstated, and I am now feeling fine. A few more notes on ship travel: Why was I surprised to see the stream of water from the faucet sway back and forth? (okay, if you want to be technical, this is a matter of perspective: in actuality, the water stayed straight and it was the sink/boat that moved relative to the vertical line of water, but the effect was still startling). Another amusing note: the dry lab was full of wheeled cushy office chairs, on a painted steel floor. Remedy? Each chair’s legs were bungeed to the nearest bench support. Depending on the bungee, this left a range of motion of each weighted chair of a foot or two. Picture it: a room full of scientists at work on their computers, all sliding in unison into their neighbor’s workspace for a moment, only to be yanked back to center, and then rolling away to the other side…
