Stephen Kade: What is Long Line Fishing? August 19, 2018

NOAA Teacher at Sea

Stephen Kade

Aboard NOAA Ship Oregon II

July 23 – August 10, 2018

 

Mission: Long Line Shark/ Red Snapper survey Leg 1

Geographic Area: 30 35’ 34’’ N, 80 56’ 48’’ W, 20 miles off the coast of Jessup, Georgia

Date: August 2, 2018

Weather Data from Bridge: Wind speed 14 knots, Air Temp: 27c, Visibility 10 nautical miles, Wave height 2 ft.

Science and Technology Log

Longline fishing is a technique that consists of one main fishing line with many baited hooks that come of that line on shorter lines, (like branches off a tree) attached at various distances. Long lines are used in both coastal areas and the open ocean and are often placed to target specific species. If the long line is suspended in the top or mid depth water, it is called pelagic longline fishing. If it is on or near the ocean floor by weighting it down to the sea floor, it is called bottom longline fishing. A high-flyer buoy is placed at either end to mark the position of the line in the water so boats can see it while submerged, and so it can be found when it needs to be retrieved. Weights are placed on each end and the middle of the line to hold the line down to a specified depth.

Longline_KadeTAS2018
Computer created infographic of long line fishing process by NOAA TAS 2018 Stephen Kade

On board NOAA Ship Oregon II, the mission is a red snapper/shark longline fishing survey in the Gulf of Mexico and the Western North Atlantic coast. I was on the first of four legs of the survey that left Pascagoula, Mississippi, rounded the bottom of Florida and stopped for 44 stations between West Palm Beach FL, up to Cape Hatteras, NC, and back down to Port Canaveral, FL. NOAA’s mission is to research current shark and snapper populations in specific areas as determined by NOAA shark scientists and related state Fishery Departments.

The Oregon II has a large spool of 3mm monofilament fishing line on deck. For our survey, we used a line that was one mile long, and had 100 baited hooks approximately 50 feet apart. The hooks are attached to the line by gangions. Gangions are 12 foot long monofilament lines with a hook on one end and a manual fastener at the other end that can be taken on and off each time the line is deployed. All 100 hooks on the gangions are baited with Atlantic mackerel.

numbering gangions
The team attaches the gangion numbers and hands over for deployment

To deploy the line into the water, it takes a team of 6 people. The first person strings the line from the spool and through various pulleys along the length of the ship moving toward the back of the boat before tying it to the high flyer buoy and returning to the spool control to deploy the mile long line into the water. A team of two works to attach a specific number tag onto each gangion, and then to retrieve the 12 foot long gangion from a barrel. The numbered, baited, gangions are handed one by one to the next team member who attaches the gangion of the main long line every 60 feet as the line descends into the water. This crewman also places three weights on the line to hold it onto the ocean floor, one at each end, and one in the middle. When all hooks are deployed, the line is cut from the spool and the high-flyer buoy is attached to mark the end of the line in the water.

deploying high-flyer
Deploying the high-flyer buoy after all 100 gangions and weights are attached.

The last member of the science team is at a computer station on deck and they are in charge of inputting data into the computer. Each time a buoy, weight, or gangion goes into the water, a specific button is pushed to mark the items place in the water. This is done so when a shark comes up on a numbered hook, NOAA scientists know exactly the latitude, longitude and depth of where that specific shark was caught. Scientists upload this important data immediately to NOAA servers for later use so they can assess average populations in specific areas, among many other data points.

Input
Each time a gangion, weight, or high-flyer buoy is deployed, its location is input in the computer.

The bait stays down on the ocean floor for about an hour before the boat returns to retrieve it. The retrieval process is similar to deploying the line except that it takes longer to bring it in, as there are now some fish and sharks attached to the hooks. If the hooks are empty, the number is taken off the line, and the gangion is placed back in the barrel until the next station. If there is a shark or fish on the line, it is pulled onto the deck and data is collected before the shark is safely placed back into the water. The first step is unhooking the fish, before it is measured. The shark is measured from the tip of the nose to various parts of the body to determine the size in those areas. The gender of the shark is also determined, as well as the maturity. Finally, the shark is weighed on a scale and most are tagged before being photographed and released. The process only takes about two minutes to safely ensure the shark survives. The data is recorded on a data log, and after the retrieval, the data is input into a database.

Removing Gangions
Gangions are taken off the long line, de-baited, de-numbered and put back in barrel.

 

Personal Log

Before coming on the Oregon II, I knew only about the fishing process on a larger scale from what I’d read about, or seen on television. I was slightly intimidated that without experience, I’d likely be slowing down the experienced team of professionals from their difficult job. As we headed out to sea, I found out it would take a few days before we reached our first station and that gave me time to get to know the crew, which was very valuable. There are two crews, each work 12 hours a day, so fishing was happening around the clock. I was able to listen to their advice and explanation of the techniques used in the long line process, and also some fantastic stories about their lives and families. Their patience with me and the other volunteers during those first few stations gave us time to get up to their speed, and from then out it was like clockwork. It was certainly hard to work outside all day, but the passion, skill, and humor of the crew made it quite fun work each day and night. It was impressive and amazing to see how this efficient process is used to help NOAA scientists and fishermen collect data from vast areas of the ocean for two weeks. I am proud to say I helped a great team to get information that can help us understand how to help populations of sharks and fish for long into the future.

Stephen removes shark
TAS 2018 Stephen Kade taking shark off gangion, ready to measure, weigh, and put back in ocean

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