NOAA Teacher at Sea
Methea Sapp-Cassanego
Onboard NOAA Ship Delaware II July 19 – August 8, 2007
Deployment of the Tucker Trawl enables researchers to sample zooplankton at various depths.
Mission: Marine Mammal Survey Geographical Area: New England Date: July 23, 2007
Weather Data from Bridge
Visibility: less then 0.5 nm
Wind Direction: West – Southwest
Wind Speed: 5-10 mph
Swell height: 3-5 feet
Science and Technology Log
Although the weather is not especially nice today, at least we have a new project to work on. Today is Tucker Trawl Day! The trawl consists of a trio of long finely meshed nets which are mounted one above the other on a heavy metal frame. The frame is then tethered to a wire cable which runs up to a crane. Also mounted on the frame is a flow meter, which is used to measure the amount of water that has passed through the net, and a Seabird mini-logger sensor which records time, depth and temperature. Deployment of any piece of equipment requires careful coordination between numerous members of the ships crew and scientists, as the boats position, and speed must be carefully controlled. Meanwhile the crane operator and those physically preparing the nets will oversee proper operation of the nets and its sensors along with the depth and speed of its ascent and descent.
The cod ends of each of the three nets have been tied with white rope and are visible in the right-hand photo graph.
Back in the dry lab several other hands are at work preparing the sampling jars, labels and documentation for the incoming specimens.It does not take long before everyone is in place and the net is lowered. The trawl will be lowered to the seafloor at which point a devise called a messenger will be snapped on to the wire cable. The messenger is a heavy brass cylinder (about the size of a small fist), which runs down the cable and hits a special releasing lever near the trawl’s metal frame. Release of this lever closes the bottom net and opens the middle net. Deployment of a second messenger then closes the middle net and opens the top net. Control of the opening and closing of the three individual nets allows researchers to take samples at specific depths. After several minutes the Tucker Trawl begins its ascent. It should be noted that the Tucker is not used to sample fish; therefore, we are not expecting to capture any vertebrates. The speed of the trawl is fairly slow so that fish have plenty of time to get out of the net’s way. What we are hoping to capture are Copepods. These tiny lipid-filled zooplankton are the primary food source for the endangered right whale. (For more information regarding copepods and right whales please read my log from July 21st 2007). Once the trawl is on deck we use a low-pressure saltwater hose to rinse the nets. We work our way from the mouth of the net downward so that every organism is rinsed into the narrow end of the net which is called the cod end.
Kate Swails, Biologist, rinses the Tucker Trawl contents from a sieve into formalin filled jars.
Then the cod end is carefully untied and its contents rinsed into a fine mesh sieve. The gauge of the mesh sieve is large enough to flush phytoplankton out of the sample while retaining zooplankton.The sieves are then shuttled to the dry lab where the contents are raised with seawater and formalin. Later these same jars will be shipped to a lab in Poland where the samples contents will be sorted, identified and counted. All copepods in the sample will also be tallied in accordance to one of six life stages. Aside from physically enabling us to put masses of copepods in jars the results of the Tucker Trawl are also compared to the results from the conductivity/temperature/depth sensor (CTD) and video plankton recorder (VPR). (Please see my log dated July 21st for further explanation and photos). Furthermore Tucker Trawls are also used to help indicate the likelihood that whales are in the area; empty trawls mean no whale food and few if any whales. Naturally, packed trawls signify ripe feeding grounds which may be worth staying on to survey.
The samples will eventually be shipped to Poland for full analysis.This soft-ball sized deep sea sponge was unintentionally caught in the Tucker Trawl.
NOAA Teacher at Sea
Methea Sapp-Cassanego
Onboard NOAA Ship Delaware II July 19 – August 8, 2007
Mission: Marine Mammal Survey Geographical Area: New England Date: July 21, 2007
Weather Data from Bridge
Visibility: 7nm
Wind Direction: West-northwest
Wind Speed: 5-10 mph
Swell height: 6 to 8 feet
Peter Duley stands with the vertical profiling package, which is the property of Dr. Mark Baumgartner, Woods Hole Oceanographic Institution.
Science and Technology Log
Yesterday and today were spent traveling down 3 transect lines. Each transect line is a total of 18 miles long and sits 5 miles apart from its neighboring transect. The 3 transects are further divided into stations so that each transect contains 6 stations which are evenly spaced by three miles. The boats captain and crew ensure that the boat is correctly positioned according to the transects and stations. Upon arrival at a given station the bridge radios the dry lab and preparations begin in order to launch an instrument called a vertical profiling package. The vertical profiling system on board the DELAWARE II is the property of Dr. Mark Baumgartner of the Woods Hole Oceanographic Institution and is operated by Melissa Patrician, Oceanographic Technician at Woods Hole Oceanographic Institution.
This trio of instruments is bolted to the inner rim of a round aluminum cage that helps protect the sensitive instruments and allows multiple instruments to be lowered in one convenient package. Three instruments are on this particular cage: One is a conductivity, temperature, depth (CTD) sensor which also happens to measure phytoplankton concentrations via a fluorometer. The second implement is an optical plankton counter (OPC). This instrument functions by projecting a beam of light against a sensor plate. When particles (marine snow, copepods, krill, or other types of plankton) pass in front of the sensor plate they block the beam of light and are thus recorded by a remote computer. The computer software then enables the scientist to sort these light-interrupting events by particle size. The third instrument is a video plankton recorder (VPR), which may take as many as 30,000 photo frames per sample. The resulting images help to give researchers a visual confirmation as to the various life forms inhabiting the water column.
After each instrument has been checked and is in sync with its perspective computer the vertical profiling package is lowered from the deck via a motorized cable. The instruments are lowered to within a meter of the seafloor and then are immediately lifted back to the surface. During the down-and-back journey all points of data collected by the 3 instruments are loaded onto three computers for later analysis.
Researchers hope that by sampling the water column they can gain a better understanding of the biotic and abiotic factors that affect copepods and their distributions. Copepods are of particular interest as they are a primary food source for a multitude of marine animals from fish fry to whales.
NOAA Teacher at Sea
Methea Sapp-Cassanego
Onboard NOAA Ship Delaware II July 19 – August 8, 2007
Mission: Marine Mammal Survey Geographical Area: New England Date: July 19, 2007
NOAA Ship Delaware II
Delaware II: Ship Specifications
Length: 155ft
Breadth: 30ft
Draft 16.6 ft
Hull: Welded steel
Displacement: 891 tons
Cruising Speed: 10 knots
Range: 5,300 nm
Endurance: 24 days
Commissioned Officers: 4
Licensed Engineers: 3
Crew: 10 Scientists: 14 (Max)
Launched: December 1967
Commissioned: March 12th 1975
Builder: South Portland
Engineering, S. Portland Maine
I arrived in Woods Hole Massachusetts at 10:30 pm and rolled my luggage up and down the main street trying to find the DELAWARE II. Following a not so encouraging conversation with a bus station security officer who said to me “The DELAWARE II never docks here”, I managed to indeed find the ship that would be home for the next 3 weeks.
A large tiger shark awaits examination and tagging
Over the course of a calendar year, the DELAWARE II will be at sea for ~200 days during which a crew of 17 will attend to her maintenance and operation. Most of its crew members are hired via the National Oceanic and Atmospheric Administration NOAA; 6 of which work on deck, 4 others serve as engineers, 2 work in the galley, 1 serves as an electronic technician, and 4 more are NOAA Corp officers. These officers are in charge of ship operations and manage all other operations which are carried out on board. The DELAWARE II conducts a variety of fishery and marine resource research in support of NOAA. The ship has also been utilized to carry out research conducted by private entities, such as the Woods Hole Oceanographic Institution, and the US Geological Survey in addition to other government agencies and universities. Typically DELAWARE specializes in 5 different survey projects which are as follows:
DELAWARE II: Surveys
The Northeast Ecosystems Monitoring Survey monitors the Northeast continental shelf by assessing both its physical and biological aspects. For example, one of the methodologies employed during this survey uses a set of Bongo tows which are designed to catch plankton, small fish fry, larvae, and other small invertebrates. These minuscule creatures are the foundations for most of the ocean’s food webs and therefore their populations are used to indicate and predict the overall health of the ecosystem. The Northwest survey is conducted on a repetitive basis so that these populations may be monitored over time, thus enabling researchers to monitor changes over time.
A smaller tiger shark will receive a tag before being released as part of the ongoing Apex predator survey
Apex Predator Survey is conducted every three years and is designed to assess the relative abundance, distribution, population structure, species composition, and to tag sharks so that migration patterns may be studied. Sharks are captured via longlining and then released after tagging and biological samples have been gathered.
Atlantic Herring Hydroacoustic Survey combines a variety of advanced technologies including multi-frequency echo integration, omni-directional sonar, and underwater video to assess hearing populations. The stability of herring populations is central to the sustainability of many commercial fisheries as well as the ecosystem as a whole.
Ocean Quahog and Surf Clam Survey conducts dredges through the silty and/or sandy portions of the ocean floor where these filter feeding bivalves dwell. Such dredges enable researchers to calculate relative abundances and thus derive sustainability yields. Since both the ocean quahog and surf clam are edible bivalves, they are of commercial value and contribute to the economic stability of the Atlantic fisheries. The surf clam is especially coveted in the restaurant and other food industries for making clam strips and chowders. The ocean quahog has a stronger flavor and is used in recipes where the clam is used in conjunction with other strong flavored ingredients like pasta dishes. (who knew you would get a cooking lesson here) Also of significance is the reproductive biology of the quahog: This bivalve is extremely slow growing and long lived, it does not reach maturity for 20 years and will live up to 200 years. Those that are eaten are typically between 40-100 years old.
Marine Mammal, Large Whale Biology aims to examine the relative abundance and distribution of the Atlantic’s large whales. A variety of data gathering methodology is used, ranging from visual and photographic recording to biopsy sampling for genetic studies. Studies which focus on the whales’ food abundance are also included in this survey.
Commanding Officer (CDR) Richard Wingrove
So who’s in charge of all this nautical navigation and science? As one can imagine there is allot going on aboard the DELAWARE II at any given time. Of course, numerous highly trained personnel insure that the engines work, that everyone gets three meals a day, that the toilets flush, that scientific protocols are being met, and that we are on course. But one individual is ultimately responsible for the coordination of these individual efforts. During my tenure aboard the DELAWARE II that role was fulfilled by the Commanding Officer (CDR) Richard Wingrove. CDR Wingrove has spent a lifetime working in, and studying marine environments. After earning a degree in Marine Science from the University of Miami, the Commander joined the Peace Corp and was stationed on the Caribbean island of Antigua. As a fisheries officer for the Peace Corp, his job was to monitor fishing practices while helping fishermen develop and implement techniques that would improve their catches. Following his service in the Peace Corp, CDR Wingrove went to work as a Satellite Oceanographer for the private sector; it was during this job that he happened to attend a conference and met a NOAA officer: Soon after, it was on to officer training school in Fort Eustis, Virginia where after 5 months of training, officers emerge with the foundational knowledge to navigate the seas and drive a ship.
Following completion of officer training, CDR Wingrove was appointed to the NOAA Ship MILLER FREEMAN which is stationed in Alaska. After enjoying the northern latitudes for two years, NOAA then sent him back to his home state of Florida where he worked in the Looe Key National Marine Sanctuary. Following two years in the sanctuary he returned to the Western Seaboard and set to work on the NOAA Ship JOHN N. COBB which is stationed out of Seattle. Again, after two years of surveying salmon, killer whales and other marine mammals CDR Wingrove was headed back to the Eastern Seaboard. This time he would spend three years based in Miami where his job was to oversee oil spill responses for South Carolina, the Gulf of Mexico, and the Caribbean. As he explained to me, working to clean up such an event is a rather delicate job since each of the involved entities including the company who spilt the oil, state agencies, federal agencies, and community leaders are each represented by their own biologists, ecologists, scientists, and researchers which then assess the spill, evaluate its impacts, and determine how the clean up should be executed. CDR Wingrove’s job was to take all the data and information presented to him by each of the involved parties, and then coordinate their findings in order to determine a course of action for clean-up, as well as monitor the clean-up process.
After three years of cleaning up other peoples’ messes CDR Wingrove was appointed as Executive Officer aboard the NOAA Ship DELAWARE II. He worked aboard the DELAWARE for two years before being sent to the Great Lakes area where he spent another three years coordinating the clean-up oil spills. Then once again he was headed back to the DELAWARE II this time as the ships Commanding Officer. CDR Wingrove will finish his service aboard the DELAWARE II in May yet he does not know where NOAA will send him next. Regardless of the locale I have little doubt that CDR Wingrove will continue his legacy of service to the natural world and to all whom benefit from healthy seas.
