NOAA Teacher at Sea
Onboard NOAA Ship Oscar Elton Sette
April 19-29, 2009
Mission: Hawaii Bottom fish Survey Geographical Area: South side of Oahu Date: April 21, 2009
Winds: 7-16 knots variable.
3-5 ft swells.
Water temp: 24 C.
Air temp: 70 F.
Science and Technology Log
Oh man, I am so happy that we’re underway! The swells found us today and we’re finally rocking around – it is great! Today, the game-plan is that at 6am the 15ft SAFE boat runs out into the sapphire blue Hawaiian waters to study the slicks (areas of converging down-welling currents- the glassy parts in the ocean) while the 19ft boat tries to find juvenile bottom-fish. Good luck!
I, however, am helping three other scientists with trawling for billfish. We’re working with the Isaacs-Kidd trawl (I/K). This is a 10 meter long net with 5mm mesh that is connected to a detachable cod-end which collects the plankton. The I/K was named after the researchers from Scripps in La Jolla who developed the technology in the 60’s. We dropped the net bearing their names into the water by an A-Frame winch maintaining just below the surface for an hour. At this time the net is retrieved and the cod end is removed for study. It is replaced with a fresh end and the net is thrown back into the water for another hour.
The cod-end is brought into the hydro-lab and the contents are splayed out into a tray and analyzed. The marine organisms are then sorted, organized and labeled for any rare or special fish – my personal favorite is the long, skinny Lizardfish in the middle of the tray. The different fish in this photo are really interesting. The small one in the top left is a Slender Mola which as an adult lives in the open water, the longer Lizardfish lives on the bottom, the Blenny lives near shore in shallow water while the Lantern-fish grows up, lives in mid-water and develops light organs. As adults they grow into different sizes, scatter into different waters in the ocean and adapt accordingly. But as larvae they are all found together—in the slicks.
The target specimens for this trawl are Marlin, Swordfish and other billfish larvae. And you know what? We caught a couple; the one pictured is a baby Swordfish. From this photo it is hard to believe this creature grows up to be the extremely muscular fish in the same sub-Order as the one Hemingway writes about, but it is true. Not much is known about the life histories of these fish, that is why we’re here, but it is believed that it takes many years to reach adult. The specimen were photographed and then placed in a 32oz plastic jar with ethyl alcohol for further analyzing later. We repeated this process 6 times throughout the day.
The I/K collects a lot of very small marine organisms. It looks like gumbo. Luckily, this isn’t our dinner; we’re fed a lot better looking— and definitely tasting— food on this cruise. We collected numerous jellies, shrimp, fish larvae, debris, eggs, nudibranchs and crabs. All of it is relatively transparent so you don’t notice it while in the ocean. The I/K concentrates the gelatinous biota and truly illustrates what is in the water. And considering the warmer waters of the tropics are less productive than colder waters, this isn’t everything that could be there. Just don’t think about this when you open your mouth underwater!
The trawl was fun and definitely a new experience. It is truly incredible the amount of life that is in the water. Until you see you it pulled out, you don’t believe it. This is one of the paradigm-shifting results from being on this ship that I am only now beginning to realize. This entire vessel is designed to study the ocean; every facet of this boat is geared toward understanding the marine world. The researchers and crew on the Sette are actively embracing NOAA’s mission of stewardship.
Question of the Day
Why are the fish we catch the colors they are—orange, yellow, red, etc? This was one of the questions I asked some of the expert marine biologists over dinner the other day and I was told that one of the reasons is that the colors makes the fish invisible. Red absorbs the spectrum of light that gets down around 100 fathoms and makes the fish look grey.
New Term/ Phrase/ Word
New words: Vog –volcanic fog. Here the marine layer is normal condensation coupled with volcanic particulates. Kai – Hawaiian for the sea; Nalu – Hawaiian for waves; Kuliana— Hawaiian for responsibility. This can be responsibility for anything: your job, your family, etc. But as Ensign Norris says, it is also responsibility for the environment and it reminds us to protect what we have.
Animals Seen Today
We saw a Laysan Albatross (Phoebastria immutabilis) today zooming the boat. It is a beautiful bird that I’ve never seen before and its wings were truly massive. We also caught a few billfish and fish larvae so tiny they look like they are just heads!
NOAA Teacher at Sea
Onboard NOAA Ship David Starr Jordan August 21 – September 5, 2008
Mission: Leatherback Sea Turtle Research Geographical area of cruise: California Date: August 31, 2008
August 29 – Longline fishing for swordfish
Today’s major objective was to catch swordfish for tagging using a fishing method called longlining. Longline fishing uses one main line held just below the water’s surface with several buoys. Attached to the main line are several smaller branch lines with hooks and bait. The branch lines extent 42 feet or 7 fathoms into the ocean.
Preparing to launch the longline is quite a sight and it requires a number of individuals, each working in unison. There is a person who baits the hooks on the branch line then hooks it to the main line, another person attaches a glow stick (used to attract the swordfish), and a third person attaches the buoy to the main line. There are also a number of people working behind the scenes sorting lines and working the winch. After all the branch lines are hooked to the main line, the line soaks in the water for several hours – in hopes that a swordfish will take the bait.
Reeling in the line took about two hours because the line was 4 miles long and held over 200 hooks. I thought this was an extremely long line but was told that commercial fishing vessels use between 40 to 60 miles of line with thousands of branch lines. Wow!
Unfortunately, we were unable to tag any swordfish but hope to try again on Labor Day. What an incredible experience today has been.
August 30 and 31 – Rock’n and Roll’n
Whoa, Whoa… is about all you heard me say over the past two days. We’re going through a rough patch today – high winds and swells up to 5 or 7 meters – between 15 and 20 feet. We sure were glad the scientific equipment was secured during the first few days – because everything that wasn’t tied down went flying – including chairs, drinks and the crew. The closest thing I could come to describing this experience would be like riding a non-stop Disney ride. The inclinometer reading (an instrument that is use to detect the degrees a boat rolls) recorded a maximum tilt of about 36 degrees. To put thing into perspective, I am now typing with one hand and holding the table with the other. Unfortunately, many of the science projects were cancelled due to high seas. We hope to be in the calmer waters of Monterey Bay area tomorrow.
NOAA Teacher at Sea
Onboard NOAA Ship David Starr Jordan July 6 – 15, 2006
Mission: Juvenile Shark Abundance Survey Geographical Area: U.S. West Coast Date: July 14, 2006
Science and Technology Log
I had the opportunity to interview Jason Larese who is aboard for this cruise. He works for the Southwest Fisheries Science Center in La Jolla, which is part of NOAA Fisheries Program. For the past 5 years he has been working with marine mammal studies, especially with dolphins. Recently, he has been working on an albacore tuna tagging project. He analyses data from special tags that record light, depth, and temperature variations which help them to track where the tuna migrate and where/what they eat. Since they know at what depths the tuna feed, they can narrow down the possibilities of what they are eating (since things tend to stay in predictable positions relative to the thermocline in the ocean). He has enjoyed working with the Shark Abundance Survey, but he hopes to return to marine mammal research soon.
They did a swordfish set last night around midnight. We hauled in the set around 6am. We caught 4 makos, 14 blues, and 6 pelagic rays. We did our first shark set around 8am. We hauled in the set around noon. We caught 3 makos and 2 blues. During our first shark set today, a small blue shark died on the line. When they did the dissection of his stomach, they found the vertebrae and jaws of a Lizardfish, and several squid beaks. It was very interesting to see what this shark had for breakfast before we caught him. I was able to keep them to share with my class.
We did our second shark set around 2pm. Dr. Heidi Dewar showed me how to take a temperature reading using the Seabird Temperature/Depth Profiler. It is a small processor in the water-tight tube, which lowered over the side of the boat very slowly, to a depth of about 150 meters. Then, it is raised very slowly. The water-tight tube is then opened in the lab and connected to a computer. The information is then downloaded and imported into Excel, where it is translated into a graph. They use this information to locate the thermocline, since many sea animals are restricted to the thermocline and above where there is a mix of warm and cold water (usually as a result of wind and waves). And, there are fewer animals in the colder temperatures below.
We hauled in the set around 6pm. During this haul, we caught 3 blues and 9 makos. One mako was badly tangled in the line, and he was not going to survive. So, the shark (now that he has died) will be taken back to a lab at SCRIPPS Institute of Oceanography where an MRI study will be conducted to examine the shark’s anatomy and physiology. (This is not Russ’ study but one of some scientists at SCRIPPS and UCSD Medical school.)
One interesting thing that happened during the first shark set, as we were setting the line, we saw loads of dolphins in the area. They appeared to be circling up fish and then eating them. Several of them were quite close to the ship. We estimated that there were at least 30 dolphins in the area surrounding our ship. We were concerned that they would try to eat our bait and end up getting hooked, but none of them did. It is extremely rare for dolphins to get hooked since they can detect the hook in the bait and avoid it.
We discovered a large mola floating near the ship, and several people tried to catch him with a fishing rod in order to try to tag it with a satellite tag. They weren’t able to catch him. Everyone is very interested in the molas, and the scientists here are collaborating on a research study to monitor their behavior and movements. I found out that the mola (an ocean sunfish) actually eat jellyfish. They don’t actually eat our bait, so when we catch one, it’s always been because the hook got caught in their fin by accident. They are fascinating creatures, and it’s amazing to see a fish that is that huge!
I helped wrangle a few sharks this afternoon, but the last one that I did was very strong and I had a hard time holding on to him. At one point, he whipped his head to the side and he yanked on my arm so hard I thought he would break free. It was truly awesome to see just how strong these sharks are, without really even trying. I also spent some time with Natalie Spear who was doing data recording during the second set. I’m amazed at how many pieces of data have to be recorded, and how many things the data recorder has to do at once. It is definitely a more difficult job to do, and with all the commotion of the scientists who are processing the animal and are requesting different things all the time, it takes a very level-head to keep everything straight, especially since accuracy in recording all the different tag numbers is essential. I have been very impressed with all my fellow scientists and their ability to keep up with all the demands of that position. And, they manage to still have fun while doing it!
NOAA Teacher at Sea
Onboard NOAA Ship David Starr Jordan July 6 – 15, 2006
Mission: Juvenile Shark Abundance Survey Geographical Area: U.S. West Coast Date: July 6, 2006
Science and Technology Log
After everyone boarded the ship and we were underway, the OOD, Junior Officer Sean Finney held a short welcome aboard meeting. He explained the expectations of the scientific crew and regulations while aboard the ship. Afterwards, the Chief Scientist, Dr. Suzy Kohin, held a meeting to explain our mission and to show us how the longlines would be set.
The mission of our cruise is to complete the second leg of the Juvenile Shark Abundance Survey, which is done annually. The first leg was completed last week. During this leg, we will resample the same blocks, so that the data can be compared. Data will then be analyzed from the last 10 years to see if there have been in changes in the mako and blue shark populations. The primary targets for this survey are the juvenile pelagic sharks, the mako and blue sharks. Any other animal that is caught will be measured and that data will also be recorded. Sharks will be tagged and released. If there happens to be a shark that is no longer alive or who is too unhealthy to be released, they will be dissected and specific parts will be preserved for further research. We are hoping that this will not happen. We will also be taking a DNA sample from each shark that is caught. At the end of each set, temperature and latitude and longitude will be recorded. Primary and Secondary Blocks have been predetermined (as these have been the same for the survey over the past 10 years); however, there are a few days in which we may do sets in areas where the temperature of the water or slope of the ocean floor appear to be optimal for catching sharks to tag.
In addition to the primary survey, we will also be doing a Swordfish Feasibility Study, which is a project being conducted by Dr. Heidi Dewar. She is looking to see if it is possible to catch swordfish in this area using a longline set, similar to the one we are using for the Shark Survey. They are also looking at whether or not it would be possible to control the fish well enough to be able to tag its dorsal fin.
Following our meetings, we practiced putting on our “gumby gear” (survival suit), which is made of neoprene and is intended to be worn only during abandon ship situations. It is called “gumby gear” because it covers a person from head to toe in bright red neoprene. Crew members aboard the ship are expected to keep their abandon ship gear close by in case of an emergency, and we have abandon ship drills and fire drills once a week. Every stateroom is equipped with two survival suits and two life jackets. Man overboard drills are conducted once every month or so.
The first longline, which we set at 4pm, was considered a practice set. Setting the longline is comprised of several jobs. The first job is done by Rand Rasmussen. He begins the process by preparing the bait. For the shark sets, we use frozen mackerel. Rand Rasmussen counts out the frozen mackerel and thaws them in 2 coolers using sea water. The mackerel are not baited completely thawed and are actually easier to bait if they are still a little frozen.
The next step is that the deck crew members prepare the lines by taking part of the line and unrolling it from the main roll. They then string it through a pulley that runs along the side of the ship. After the line is ready, the bridge positions the ship so that we are in line with where we should be setting the line. Then, when everyone is in place, they toss the flag. The flag is a flag that is connected to a long pole. The bottom of the pole has a float on it, so that it stands upright. There is also a bright yellow bag that looks like a windsock (called a sea anchor), which is also thrown into the water. This catches the current, and helps to keep that end of the line straight.
Then, one person will unclip the leaders. These are made up of a gangion clip at one end, about 3 fathoms (18 feet) of steel wire, and a stainless steel hook at the other end. The gangions are kept in cans, with 2 rows on 4 sides to which the gangions are clipped. The hooks are looped inside one end of the gangion to keep our hands safe and out of the way from hands that might reach into the can. There are 2 cans of gangions/hooks, and we set around 200 hooks during each set. Once the gangion is unclipped from the can, the hook is removed from the loop, and both ends are handed off to the baiter. The baiter puts the hook into the mackerel’s mouth, then loops it out the underside of the mouth and is then pushed into the back, making a sort of loop around the spine with the hook. The line is then pulled tight.
The baited line is then passed off to the “clipper”. This person waits for a small crimp to pass by on the line as it comes through the pulley and goes down into the water (towards the flag). There are actually 2 small crimps on the line which serve two purposes. First, they keep the gangions from sliding off the line or moving positions. Second, it makes sure that the spacing is uniform on the line. The spacing for this survey is about 25 feet between each gangion. The clipper grabs the line with one hand, and then clips the gangion into the “slot” with the other. The line moves very quickly because the ship is actually moving forward the whole time at a few knots, so the clipper must be fast and accurate.
After 5 baited lines have been clipped, a buoy is clipped on in what would then be the 6th slot on the line. The buoy goes through 2 stages of preparation. First, the buoy is taken from the port side of the ship, where they are stored while not in use. Then, they are clipped on a line near the setting line. One person takes a leader line of nylon rope (again, about 3 fathoms long) and they attach it to the buoy. Then they pass it off to a buoy person, who counts the gangions as they go by and then passes the buoy off to the clipper at the appropriate time.
While the scientists are working with the line, the deck crew is also working with the line at the winch. There are always at least 2 deck crew members on hand to supervise the set. One person runs the winch, and they can adjust the winch to run the line faster or slower as needed. The other person carefully watches the line, to make sure that everyone is being safe and that the line is moving along safely. They signal the winch operator if the line needs to be stopped or sped up. They also keep in constant contact with the bridge to tell them how the set is going.
The bridge can watch the set process through a camera, which they can maneuver so that they can see the line as it comes off the winch, as it is being baited, and as it is deployed in the water. In addition, they can see the line on a computer screen which shows them the “box” where they are trying to set the line. The box is an area on the navigational chart that the scientists have determined as the area in which they would like to set the line. We aren’t concerned about keeping the entire set within the box once we start, but the start point is selected so that most of the line will be in the box. The bridge is responsible for watching for any other boats/ships that might be in the area which could interfere with our line.
Once all the buoys and lines have been deployed, the deck crew disconnects the lines from the winch and attaches the line at the back of the ship. The bridge then watches the line while it “soaks” to make sure it stays as straight as possible. The standard length of soak time for this survey is 4 hours. While we are soaking, the scientists usually take a nap, play a game, catch up on email or research, relax on deck or in the crew’s lounge, get a temperature profile, prepare tags for the haul, catch up on data entry from previous sets, etc.
When it is time to haul, all of the scientists and 3 deck hands are needed. The set up is a little different when we haul in the line, because there are 2 main areas of activity instead of just one. At the very rear of the ship, there is the tagging/measuring area. This is done on two levels. The top level, which is on the same level as the aft deck, is where the data recorders and the deck hand that is operating the platform/cradle lift are located. They are on opposite sides of the ramp. The bottom level is at the bottom of the ramp and is where the platform and the “cradle” are located. Usually Suzy Kohin, the Chief Scientist, and 2 or 3 other scientists are down on the platform during the haul-in. I will explain more about all these jobs below.
The area of activity nearest to the front (bow) of the ship begins with the deck crew members and the line. Once the line is disconnected from the back of the ship, it is brought forwards so that it is in line with the winch. It is threaded across a sort of pulley, and is reconnected to the winch. Two deck hands make sure the line is wound back on the main roll of line evenly. To do this, one person operates the winch’s speed, and they can stop it if necessary, while the other person keeps pressure on the line by holding it with a special tool. This makes sure the line winds correctly and does not get snagged.
Once the line is connected, the process is ready to begin. The bridge gives permission for us to begin hauling in the line, and the first person, who stands near the pulley, unclips the gangion from the line. That person then passes it off to one of two de-baiters. These people pull the bait off the hook and drop it into the ocean. They then put the hook into the gangion loop and pass the whole thing back to the clipper. The clipper then clips the gangions back into their can (the exact reverse of the process when we set). When buoys come up, the buoy line is handed over to a buoy person, who pulls up the leader line and disconnects the buoy from it. They then coil the leader back into its basket while another person takes the buoy to the other side of the deck and attaches it to a line where it is kept while not in use. If there is an animal on the line, everyone yells, “Shark!”, or whatever the animal is. This alerts those at the rear of the ship that there is an animal coming to them. The line that has the animal on it is unclipped, and then a “rope leader” is attached to it, which makes it possible to tie off the line to the ship if there are too many to be processed right away. Then someone “wrangles” the shark to the rear of the ship by literally walking the animal along the side of the boat until they reach the cradle. It’s a very important job because they have to keep enough tension on the animal that the hook doesn’t slip out of their mouth, but they have to also be careful not to pull the animal up and out of the water, which could cause injury to the animal.
The cradle is a sort of half-tube that can be raised and lowered so that it is either closer or farther away from the water. When an animal is brought around, the cradle is lowered so that it is in the water. One of the scientists takes the leader line and takes off the rope. They then pull the animal into the cradle so that its head is facing the port side of the ship. The other scientist is waiting for the animal and he catches its mouth and eyes with one hand and covers the animal’s face with a wet cloth so that it can’t see and to help calm the animal. He uses his arm and other hand to hold the animal down. The scientist that lead the animal into the cradle also gets down on the platform and uses his arms to keep the animal still.
The first thing that is done is a DNA sample. This is done by the Chief Scientist who uses hemostats to hold a small section of the animal’s fin (in the case of a shark, this is the dorsal fin). Then a small scalpel is used to remove a tiny section of fin. This is held in the grip of the hemostat, which is then passed up to the data recorder on deck. They put the sample into a small glass jar which is then labeled with the animal’s number and species. Most DNA samples collected were from makos because the researchers are trying to determine the population genetics structure of the shortfin mako shark in the North Pacific, though 3 other types of animals were also caught.
Once the DNA sample is done, the Chief Scientist inserts an ID tag, called a spaghetti tag, which is from NMFS (National Marine Fisheries Services) into the animal, just in front of the dorsal fin. This is done by making a very small cut with the scalpel, and then the tag is inserted with a long metal probe, which lodges the tag underneath the skin. The tag information is recorded by the data recorder, who later completes a registration card which will identify the animal by the date caught, length, sex, and species. The registration card is kept on file, so that if the animal is ever caught in the future, they can track where the animal has been.
After the spaghetti tag is done, they do another tag, which is placed directly on the dorsal fin. This is called a Roto tag. To do this, the Chief Scientist punches a hole in the dorsal fin with a punch tool. Then, the tag is lined up with the hole and is riveted together. This tag number is also recorded by the data recorder. On some animals, they also place satellite tags and pop-off archival tags, but I have to learn more about how those work. We didn’t do any of those today. The Roto tag has a special tag on it with instructions for fishermen. If the animal is ever recaught, they can send the tag and some of the animal’s vertebrae in for a one hundred dollar reward. This is only done on animals which receive the OTC injection.
Once the animal has been tagged, they turn it on one side to get the sex. This is also recorded by the data recorder. Then, they inject the animal with OTC (oxytetracycline) which is supposed to stain the animal’s vertebrae, which can later help to determine the age of the animal (like the rings on a tree). It also works as an antibiotic, though that is not its primary purpose. This injection is given just about in the middle of what most people would consider the belly of the animal into the visceral cavity. The dosage is based on the approximate length of the animal and is measured out of a small needle. The Chief Scientist gives the injection and holds the tiny hole where the injection was given for a few seconds to prevent any of the OTC from leaking out.
Then, they flip the animal back onto its stomach so that they can remove the hook. They record where the hook was located (either the jaw or if they swallowed it). They usually have to cut the barbed end of the hook off with bolt cutters. The line and the broken hook are then thrown up to the deck to be recycled and refitted with new hooks for use again.
Once the hook is out, the animal is pushed to the end of the cradle and the tip of its nose is lined up with the very edge of the cradle. The side of the cradle has a measuring stick on it. They hold the tail out straight and measure to the very end of it along the tape. Once they have a measurement, they lower the cradle down into the water, and gently push the animal out the end so that it can swim away. Usually makos dive straight down, but blues tend to swim around a while on the surface before diving out of sight.
Everything happens very quickly, so those who are processing the animal must be quick and efficient. The entire process takes no more than a few minutes, which is intended to limit the amount of stress on the animal, and so that we don’t keep them out of the water any longer than absolutely necessary.
When we pulled out of the harbor, I was standing on the fly bridge (the very top). I could see all the other ships and the other boat yards. One cool thing I saw was the Naval Dolphin Training Station. It just looks like a bunch of square cement rings. I could see the dolphins in them, though I don’t know if the pix came out or not. I also saw a pier that was loaded with sea lions. In front of that, we passed a buoy marker which had become the napping place for 2 sea lions…they were very cute. Once we were at sea, I was able to get in my room (room 01-1) and put my things away. Then, I hit the bed and fell sound asleep. While I was asleep Chico Gomez, Chief Boatswain, and Sean Suk caught some Bonita….very pretty fish! I didn’t get to see them whole. But, the meat was a gorgeous salmony-pink color. They said they will smoke it tomorrow afternoon. They said I can try fishing sometime this week. I will give it a try in a few days.
Because this afternoon was our first set, everyone was very excited to do all of the jobs. I chose to do baiting first, and then I switched to doing the unclipping. Both were fun, and everyone talks and laughs, so it was fun. I was really excited to finally be on board and to get to meet everyone. Hauling in the first set was amazing, and I got to see so many sharks! After the set, I spent the time unpacking and getting things ready for the rest of the cruise.
We caught 11 blues, 3 makos, and 1 pelagic ray. We also caught 1 mola mola, but I didn’t see it. I am looking forward to seeing a mola at some point. I couldn’t believe how different it was to see sharks so close, and not in an aquarium!
Today I learned how to tell the difference between a mako and a blue shark…the makos have more streamlined noses, a more silvery color, and they have a more symmetrical tail. The blues have a definite blue color to them, and their tails are distinctively larger on top than on the bottom. Also, makos have a more “thick” area in front of their tail, kind of like the keel of a boat, whereas the blues are more streamlined. You can also tell the difference by their teeth. Mako sharks have little, almost needle-like teeth, whereas the blue sharks have triangular teeth which are serrated on the sides (that is, if you happen to get close enough to see one with its jaws open!). But, they are all very cute!
The ray was also very amazing to see…they are a kind of steely-grey color, and kind of “spaceship” shaped. Very different than the rays I’ve seen around the waters near Florida. I can’t wait to see more sharks and other sea animals tomorrow!
Lat: 18 41 N
Long: 158 19 W
Sky: Sunshine with scattered cumulus; beautiful day.
Air temp: 27.3 C
Wind: 68 degrees at 8 Knots
Relative humidity: 47.9%
Sea temp: 27.1 C
Depth: 1674m (at 1800 hours, Lat 18 25N, Long 158 27W)
Sea: A few white caps tonight. What might they foretell?
Science and Technology Log
Pretty good day on the line. We tagged a yellowfin tuna (on board) and a broadbill swordfish (in the water). In the latter case, the tag was attached by sort of harpooning it into the animal from deck. We also pulled in a snakefish (head only), a big eye tuna, 2 escolar, a barracuda (of no interest so simply cut off the line) and 3 blue sharks. One was too large to safely bring aboard; it was cut loose. The two others were brought on board. From one we took blood and fin clips after which it was released. One fish was brought in by trolling today.
As you have noticed water temperature here would be quite comfortable for us (but we are not taking afternoon swims). Rich explained to me that here there is mixing of the surface layers such that the surface temps. I have been reporting would apply to a depth of about 100 meters. Then between there and 400 meters we would see about a 10 degree C drop. While some fish stay in the upper layers others hang in the depths or make regular vertical transgressions across these zones.
Fish are generally regarded as having body temperature at or very near ambient. Any heat produced in the muscles by aerobic respiration is picked up by the blood and circulated through the gills where that heat is dumped efficiently to the environment. Some saltwater fish (no freshwater ones) including tunas and some sharks have developed a kind of heat exchange system. Heat from venous blood is passed to arterial flow in order to keep certain muscles and organs above ambient temp. by as much as 20 degrees C in large fish. This allows body tissues and organs to work more efficiently.
Billfish such as swordfish also have a heat exchange system but it is located only around the eye and brain. Here certain eye muscle is reduced to little more than a container for mitochondria which generate lots of heat. The heat exchange system then only serves this region of the body keeping it above water temp. Still busy at Cross Seamount. The fishermen must be having a big time up there. We are setting at Swordfish again tonight. (Lat 18 17N Long 158 22W at finish of set)
Those oily escolar are not being kept for consumption. This morning we took one’s eyes and made a short incision along the belly just to take some muscle tissue In returning the escolar bodies to the sea I have scored their diving entries 1-10 as in competitive events. Most have been dropped straight in, but this morning I thought of trying something with a higher difficulty factor — a one and half back flip with tail entry. But on its first rotation, a bit of the entrails was ejected shipward striking me on the shoulder before falling to the deck. Unfortunately, this was not captured on film for replay tonight on “Funniest Ship Videos”, but for those present, it provided a good bit of humor to start the morning. Hereafter, we might just stay with the less ambitious dives. Spectators were glad it was I and not they.
Later I made my debut as a shark wrestler. As a rookie I was given the tail end. Even though the blues are comparatively tame once on board, the strength in the animal’s body was very evident as it tried to move – – not so sure I care to deal with the other end of these babies!
This question relates to paragraph two of the science log. What is the thermocline within a body of water? How would you expect a temperature profile to change through the seasons in a deep lake in central Pennsylvania?
Lat: 18 39 N
Long: 158 17 W
Sky: A few more cumulus clouds around today (40% cover) but they didn’t seem to get in the way of the sun too often. Some thin stratus and cirrus around too.
Air temp: 26 C
Wind: 120 degrees at 3.5 Knots
Relative humidity: 56 %
Sea temp: 27.1 C
Depth: 959.3 m
The sea was very,very smooth throughout the day.
Science and Technology Log
The line last night was put out at Swordfish Seamount (500 meters deep), about 35 miles south of Cross. It was a bit longer than usual. Longline retrieval began 0800 and was not complete until 1130. Both the length and our better fortune accounted for the longer effort. We brought in 7 on the line today including 4 sharks. Species included the following: 1 snakefish (Gempylus serpens – 104 cm long and about 7 cm wide with a big eye, pointy snout and lined with very sharp teeth– dead), oceanic white tipped shark (Carcharhinus longimanus) alive, 157 cm and nasty; a blue shark (Prionace glauca), alive, 132 cm and 32.5 kg, rather docile onboard, very pretty coloration — grayish belly softly blending to a blue dorsally; a big eye thresher shark (Alopias superciliosus — love that name) a bit of life in him but not much, 136 cm + tailfin, 51 kg, its curved tail fin nearly the length of his body; a silky shark ( ? ) alive; an ono or wahoo, a dolphinfish and an escolar. I took some samples of blue shark and thresher shark teeth. A pretty exciting and busy morning. For most of these fish their fate in our hands was the same as usual. But the real excitement was bringing on the live sharks. As they are drawn near the ship, netting held in place on a 3 foot by 6 foot rectangular metal frame is lower to the water by a winch. The fish is brought onto it and hoisted aboard. There are a few seconds of near terror as this thrashing animal hits the deck wielding danger at both ends of its body. A mattress like cover is thrown over each end and weighted down by human bodies (mine was not one of them today, but I’ll take my turn eventually; how many people do you know who have ridden a shark?).
The oceanic white and the silky were tagged with the pop ups. To do this a hole is drilled through the base of the dorsal fin. Line looped through that hole attaches the pop up to the animal. Fin clips and blood samples (if possible) are taken as are any remoras attached to the sharks. Then another moment of fear — restraints are withdrawn and animal is sent overboard as quickly as possible. Description of the satellite pop up tags: Each is about 12 inches tall. At the base is a light sensor, above that a cylindrical housing about 1 inch diameter, next a swollen area about 1.75 inch diameter (the pressure sensor) above which is an antenna about 6 inches long. Each costs about $4000.00 including about $300 satellite time to upload data. Since a signal cannot be sent through seawater to the satellite, the units acquire and store data until a preset pop up date (8 months is about max given battery power of the unit). Then they are released automatically, pop to the surface, find a satellite and dump info to it. The system allows us to track fishes vertical movements (by pressure changes) and horizontal movements by measuring ambient light levels. The latter tells us daylength which can be used to estimate latitude to perhaps within a degree and time of dusk and dawn, which when compared to Greenwich can indicate longitude.
But what if the animal dies before the 8 months are passed? If the animal is headed to the depths, at 1200 meters pressure causes release of the pop up. If no vertical change is detected over 4 days (animal has died in shallow water), they release. Other things can happen that disable the pop ups. They might get broken or eaten by other animals. Only about i in 3 tagged swordfish and big eye thresher sharks are heard from if tagged. Those animals go surface to 600 meters often and rapidly subjecting tags to quick temperature and pressure changes that might disrupt operation of the device. In spite of the obstacles, data is gathered from about 60% of the pop up tags deployed. An alternative is small archival tags that get implanted right onto the animal. These cost only $800 and have much greater storage capacity than pop ups so can provide much more data. However, these must be recovered — the fish have to be recaught in order to get the info from the tag. That’s a tough order in this big ocean and recovery rate is indeed low. Setting longline again tonight in same area. At 2042 we are at lat 18 16 N and long 158 27 W.
Last night was spectacular. Brilliant stars horizon to horizon — a star show above, including the Southern Cross, that was equaled in beauty and wonder by the light show in the water. Bioluminescent organisms were ablaze off stern. It looked like the Milky Way in the water but with the stars turning on and off and swirling about in a frenzy. Some were mere points of light, sometimes things flashed as a light bulb going quickly on and off, and once in a while a ghostly basketball sized sphere tumbled through the view. It was hard to know whether to look up or down for fear of missing the next dazzling event.
And yes, there was a small crowd at the bow to admire the moonrise at about 2345. The ship as always held its position near the longline set. As such we are sort of at the mercy of the sea, just rocking and rolling as it moves beneath us. It is to me a very pleasant motion, one that just rocks you gently to sleep. I have never been on a cruise ship, but friends who have tell me there is no (or little) sense of motion to the ship. Perhaps this is comforting to some, but I like the total experience (within reasonable limits, of course) and these last two nights have been perfect in all respects. I am handing off my duties as brake and bait man to others this evening so that I might digest and organize some of the info passed to me by Kerstin and others in the last couple days.
Here are a couple relating to ocean currents. Look at a chart that shows ocean currents along the US east coast (southern and mid-Atlantic states) and for the US west coast (Washington to California). What is the general direction of the flow along each coast? Along which coast, especially in summer, would you expect ocean water to be warmer? Why?
I have given you daily temperature readings for the sea water here at about 18 degrees north. The Galapagos Islands straddle the equator far to the east of here off the west coast of South America. You would most likely expect the water there to be warmer on average than around the Hawaiian Islands. Is it? If not, what accounts for the difference?
Lat: 18 12 N
Long: 158 26 W
Sky: beautiful day; blue sky with scattered cumulus
Air temp: 25.9 C
Wind: 70 degrees at 6 knots
Relative humidity: 52%
Sea temp: 27 C
Depth: 3571 m
Scientific and Technical Log
The longline brought in just two escolar (Lepidocybium flavobrunneum), an oily tuna (not ones we keep for eating) that tends to live rather deep. It is a dark colored fish unlike the shallower water tunas and mahi we have brought up which are nicely (sometimes brilliantly) colored. Its eye is very large and reflective like a cat’s eye though silvery. It is quite striking. So anyway, a bit of excitement there, and I got to see a species new to me. I don’t think I gave any description of the longline retrieval yet. The ship maintains a course to keep the line perhaps 30-40 degrees off port side. The line comes up midship over a pulley at the spool and is wound onto the spool. As leaders come up they are unclipped at the pulley and passed to others who remove bait and return hooks, leaders and clips to storage barrel. If a fish comes on, the spool is stopped until it is landed and removed from the retrieval area. It is a challenge for crew on the bridge to maintain the proper course for the ship with respect to the line. Because the ship is moving slowly during the process and the process must be stopped for fish or entanglements, recovery of the line takes much longer than the set. I don’t think we’ve done it in less than 2 hours. Nothing came up by trolling today and no plankton tows were done. Tonight we are south of Cross Seamount (at 2000 we are at 18 08 N, 158 27 W) to set the line. Again we are not at Cross because of another boat’s presence. I’m the starter on the bait box tonight. I hope I can fulfill the duties, after all I’m a rookie and used to coming in only as the closer so far. I guess they’ll try anything to change our luck.
After completing my log last night at about 2030 I went to an upper deck where we have strung a hammock. I was a beautiful starry night — the clearest we have had. A warm gentle wind blew over a sea rolling under us as one foot swells. The bright orange waning gibbous moon rose 20 minutes later a cast its long shimmering light across the water as it rose higher. The Big Dipper was easily apparent pointing toward Polaris only 18 degrees or so above the horizon. As new constellations took their place above the eastern horizon a couple of meteors streaked by. I was reluctant to leave the scene for my cabin. I made the mistake of telling folks about it today; there could be some competition for that hammock tonight!
In preparation for upcoming editions of the log I spent an hour or so with Kerstin discussing her work with vision in these pelagic fishes. Wow! I’ll be sorting that out for awhile — very interesting stuff. I finished a book, The Great Biologists, written in 1932. Obviously many more recent greats are not included, but I enjoyed reading about the men included from a 1932 perspective. It is of interest to me to learn more of the impact of particular work at its time in history and of the personalities of the men themselves. It adds some new dimensions to teaching of biology that might captivate a few students as bits and pieces can be appropriately included. We had a small group of dolphins leaping high as they passed the boat. Flying fish are a common sight; crewmen report that often they are found on deck in the morning. We have a pair of birds, a type of booby I believe, hitching a ride with us. They are leaving their mark all over the bow which is not pleasing the crew and have thus been dubbed “John’s nemesis”. But for those of us who don’t have to swab the deck, it is neat to have them around and to watch them feed. From their perch they seem to spot a fish leap from the water and take off. They follow the fish 10-20 feet over the water as it swims and at an instant make a fast dive for it and quickly take flight again. Many of us had our supper on the deck tonight — my first mid-ocean picnic. A clear horizon at sunset gave me another view of the green flash. Venus (I think) set about 2135 just as set of the longline finished. And as predicted, there is a crowd gathering on the bow for moonrise.
There is no “south pole star” as we think of Polaris as our “north pole star”. How can you use the Southern Cross to point you in the direction of the south pole?
Local Time: 1600
Lat: 19 19 N
Long: 155 57 W
Sky: thin overcast
Air temp: 25.5 C
Wind: 348 degrees at 9 knots
Relative humidity: 59.9
Sea temp: 26.6 C
Depth: 1997 m
Technical and Scientific Log
Longline retrieval began as usual at 800 hours (Can you tell I’m getting more than just my sea legs?). Everyone was feeling optimistic as various (secret) measures were employed through the night to ward off another disappointing haul. We did begin with a bit of bad luck as the line somehow got under the hull. (Obviously we have a few kinks to work out of the rituals.) Rich indicated that we had lost a couple big ones because of that. But we did land 4 fish – 2 dophinfish, alive, and 2 broadbill swordfish (Xiphias gladius) both dead on arrival. The latter were young fish just over 100 cm and each with a bill of about 52 cm which I collected. Hoping to get them home, but airline security might have something to say about that. We also brought on a couple yellowfin and a skipjack tuna while trolling through the afternoon and evening.
Yesterday I gave you an idea as to how Michele will use the blood, liver and tissue samples she is collecting. I am gathering muscle tissue samples for Brittany who is a grad student at Univ. of Hawaii, I believe. Those samples are to be used for stable isotope analysis of these pelagic fishes. I cannot recall enough about this and no one on board can help me give you an explanation of that work, but I will get details eventually. Let it be enough for now to say that the data collected should provide info on the trophic history and possible migration patterns of these fishes.
Some pilot whales and dolphins swam with us briefly today. No day time plankton tows today.
The depth of our longline sets the past couple nights has been about 40 meters. Depth of set depends on what you are trying to catch and the lunar cycle. Rich suggests that perhaps we should have been deeper. On full moon, for example, you would set deeper than at new moon. The fish tend to adjust their depth to maintain a rather constant level of light.
We are not setting the longline tonight. Winds have calmed outside of this area so we are going to head away through the night in search of happier hunting grounds (or should I say “fishing waters?”)
Given “gentle” seas, life on this vessel is very comfortable. Of course, gentle is a relative term and one that I hope in short time comes to be useful to me in situations that currently bring on thoughts like “why did I ever decide to do this?” (That only happened Sunday into early Monday; I’m having a great time since then.) Today I want to tell a bit what it’s like on board.
Most interior space in the ship is air conditioned; only stairwells are not. This contrasts quite favorably to the first research ship I went on. I remember very well the mens’ quarters — hot, hot, hot as it was just forward of the engine room, always smelling of diesel, “bunks” 3 high with about a foot of head room, and only a red lamp for lighting.
Here,I share a room about midship just above the main deck with Rickard, a Swedish graduate student working with Kerstin on the vision studies. Our stateroom is about 10X15 feet. It is carpeted, we have bunk beds, a desk, sink, closet and a window. We share a toilet and shower with one other person, a crew member, in the adjoining room. I think all of the science personnel are on this deck.
Meals/food service are excellent. The galley is always open and we may help ourselves to a variety of treats, snacks and real food at any time of day. For breakfast, cold cereals, bread, fruits, hot drinks and juices are available and the galley staff will prepare eggs, pancakes, meats, hot cereals as to your order.
Lunch and supper always include a salad bar and your choice of 2 entrees and a variety of side dishes. Not that we are on a strictly fish diet, but all of the fish that we have taken for specimens are immediately iced down and saved for the cooks who have many ways of making them a treat for the palate. Tonight featured freshly caught ahi cooked on a grill on deck.
Last night’s sunset was a beauty. I saw for the first time, the “green flash”.
Lets turn to the atmosphere for a few questions. If you are keeping up with answering the questions (or just look above), you have an idea of the latitude of the islands. What is the name, including direction, of the global wind belt the Hawaiian islands lie within?
The ship has been sailing along the west coast of the big island, Hawaii. Is this the windward or the leeward side of the island? The heights of Maui and Hawaii help create the weather observed on different parts of the islands. Look at a map of Hawaii and find the towns, Hilo and Kona. Which of the two would you predict to have the drier climate? Why? Check some other sources for precipitation records to find out if you are correct.
You can try the same for Maui. Hana is on the east side and Lahaina is on the west. Make some predictions as to the relative climates of each town then check other sources of climate data to see if you are correct.
If you have any questions, please send them my way.
This morning we set sail at 10AM. After lunch and drills, the crew set out a longline of about 2 miles of un-baited hooks which were immediately retrieved. This was done as a test of equipment and to help crew get the rhythm of the procedure. I was asked to stand by the spool as line was fed to the stern. My role was to watch for any slackin the line, brake the spool to take up any slack or stop the spool if it tangled (bird nested). All went well on the test.
Scientists and their teams were busy setting up their respective labs and preparing for the work ahead. One team will be doing vision studies using retinas removed from selected animals. Muscle tissue and blood samples will be taken for other studies. Plankton tows will be done at daylight and night to collect specific types present at those different times of the day.
Some fish will be tagged and released. The pop up archival tags record an animal’s depth, latitude and longitudes and other data as it moves through the ocean over a specified period, perhaps 8 months. After that time, the tag automatically is released from the fish, pops to the surface and transmits its data to a satellite.
The longline was set to be deployed at 8PM, but due to rough seas that effort was cancelled. So as you can tell, this was a day of preparation, with the real science soon to come.
I arrived Friday, April 30 after nearly 23 waking hours, 5000 air miles and 10.5 air hours from Harrisburg, PA. It was not difficult to find comfort in my upper berth aboard the SETTE. On Saturday, I was up by 8AM, walked about Honolulu most of the day. I had brief tour of the ship with chief scientist Rich Brill. By Sunday, I felt well rested and comfortable at sea until after supper. By then things were a bit rough and most of supper and perhaps a bit of lunch came back up. But I slept well — horizontal felt best.
Question for Today:
Locaction, location, location:
Determine the change in latitude and longitude from your home to Honolulu. How many time zones are crossed? State the westernmost and easternmost longitudes of the entire Hawaiian Island chain. State the northernmost and southernmost latitudes of the Hawaiian Island chain.