NOAA Teacher at Sea
Aboard NOAA Ship Oregon II
April 5 – April 20, 2017
Mission: Experimental Longline Survey
Geographic Area of Cruise: Gulf of Mexico
Date: April 10, 2017
Winds at 10 KTS
Waves at 2-4 FT
Science and Technology Log
We have continued to move between deep stations setting the baited line and hoping to catch deep water fish and sharks. These deep sets require longer soaking time to allow the hooks to reach the bottom. The downside is that we have been retrieving one set of gear and putting out one set of gear in a 12 hour period of time. Some sets have a few fish and some we get a big goose egg. There is always anticipation though as the 100 hooks are brought up. Everyone stands in their spots waiting to hear either “fish on,” “shark” or everyone’s favorite, “hard hats!” which means there is a big shark and it’s time for the sling. Below you will see the awesome Great Hammerhead (Sphyrna lewini) we caught.
The first few days we have been fishing deep in the Mississippi Canyon. The Mississippi Canyon is a geological formation in the Gulf of Mexico. It is located in an area which is part of the territorial waters of the United States. We put out some deep lines with the deepest at 1900 feet. These lines soaked four hours once fully deployed. They soak longer because they have so far to sink to get to the depth the scientists want to fish at. When we deploy a line the first thing in the water is the High Flyer, which stands like a beacon and bobs in the water marking the start of our fishing line. The next thing over the side of the ship is a weight that helps carry the line to the desired depth. Halfway through, another weight is deployed, and after the 100th hook, the third weight goes in. The last thing over is another High Flyer to mark the end of the line. If it is dark outside, the High Flyers have lights attached on top that flash so that they can be seen.
At our last deep station we caught a Mexican Grenadier, Coryphaenoides mexicanus. This fish is very unusual in color and appearance. If you feel the scales on the fish you find that they are very unique. Each scale has tiny sharp, thin spinules. As you run your hand over the fish you can feel these scale modifications. The eyes are bulged due to the pressure change of coming up from such deep depths. The scientists determined the sex of the Grenadier and then it was frozen for future study.
We also caught two Cutthroat Eels, from the family Synaphobranchidae, that were both females. Synaphobranch means unified gill… the two gill slits join together making it look like a cut throat. They are bottom-dwelling fish, found in deep waters. The eels were weighed, measured, and the scientists determined the sex and maturity of each eel. It is important that they make accurate identification of specimens and collect data. The scientists work together using personal knowledge and books when necessary. There are times on deck when the scientists will stop to examine a species and will take multiple pictures of certain identifying parts so that they can look at them closely later.
One of the great things during a watch is being able to talk with the scientists. I am an avid listener and observer. This is what they do year in and year out and they love what they do. I am a quiet observer a lot of the time. I listen and then ask questions later. It’s not exactly easy to carry around paper and pencil to take notes. But during the transit portions or soak times I ask more questions and gather information to share in my blog posts or for the lesson plan I will be writing when I get home.
The food has been great here on the ship. Our stewards have fresh salads, and menus that include two main course options, a daily soup, dessert and multiple side choices. There are snacks available 24/7 so you are never hungry. Because the meals are so great you see most people trying to fit in a workout during the day. I have been introduced to the Jacob’s ladder for workouts. I never liked hills and now I can say I don’t like climbing ladder rungs either. That machine is evil!! However, I will continue to do cardio on it as the food is excellent and keeping food in your stomach helps prevent sea sickness. I will happily eat more than I usually do if it means I don’t get seasick. An example of a typical lunch would be today when we had choices of salad, reuben, tuna melt, french fries, sweet potato fries, cookies and several other sides.
Today started with us catching two Cutthroat Eels and a Mexican Grenadier. You can see from the pictures I have posted that they look very different from most fish that you see. They really are that color. It was a shock after the sleek sharks and the bright orange Red Snapper I had seen on previous sets. I was busy watching the scientists using their books and personal knowledge to identify each species accurately. After we finished the work up on the fish we caught we headed for the next station. Now we are back to shallower fishing and expect to catch sharks, red snapper, and a variety of other fish.
I can honestly say that the 12 hour shifts start wearing you down, and sleeping is not an issue once you climb under the covers. The waves will wake you up now and then. And some mornings I wake up and can smell them cooking breakfast but sleep overrides the smell of food because I know how long it will be till I get to bed again. Walking out on deck each morning to views like this does lead to a smile on your face, that and the music that is playing loudly on the deck. Yesterday it was Hair Nation…. taking me back to the 80’s.
Did You Know?
The Gulf of Mexico is roughly 995 miles along its longer, east-west axis. It has a surface area of about 600,000 square miles.
A wide variety of physical adaptations allow sharks to thrive in the Gulf of Mexico. They have powerful smell receptors. The sensory organs lining their prominent snouts, called ampullae of Lorenzini, can detect movement of potential prey even if the sharks cannot see it. These sensory organs assist in trailing injured marine animals from great distances. They help sharks locate all sort of other things, too– shrimp boats, other sharks, birds, turtles (tiger sharks a big turtle eaters!), even boats that are dumping trash.
The skin on a shark is smooth if you run your hand head to tail and rough like sandpaper if you run your hand from tail to head. At one time, sharks skin was used as a form of sandpaper. The dermal denticles, or skin teeth, can be different from species to species and can sometimes be used as a character to look at when trying to identify one species from another.