Sunday, March 14, 2010
Friday, March 12, 2010
John and Viv deploy the TOAD each night and make 3 or 4 passes over the reef to assess coral coverage and other bottom features. They were particularly happy to have found several areas of reef with the coral Euphyllia paraancora. This coral is found in the tropical Western Pacific and the Indian Ocean, but it is not common. It is heavily harvested for the aquarium trade and more susceptible to bleaching than more robust coral species. It is listed as vulnerable and is further threatened by the predicted threats of climate change and ocean acidification. It was put on the IUCN Red List and is protected via CITES, both as of October, 2009.
Above: HARP Diagram
One night we deployed a HARP, a High-Frequency Acoustic Recording Package used to study cetaceans (whales and dolphins). The scientist in charge of this equipment was not onboard but had arranged with the Chief Scientist to put out this equipment near Saipan. This HARP will sit on the seafloor for 2 years collecting sounds. HARPs record ambient ocean noise including low-frequency baleen whale calls, high-frequency dolphin clicks, sounds in between and man-made sounds from ships, sonar, and seismic exploration. When the HARP is retrieved, the sounds can be analyzed and we will learn more about the cetacean populations of the Mariana Islands.
A few days ago, Glen gave me a great tour of the engine room. It is beyond the scope of this blog to describe it here, but I can’t resist including a few pictures. I am always amazed by what it takes to keep a ship like this running. They call it an “unmanned engine room” because an alarm will ring if something needs attention like overheating or low oil pressure. It may be called “unmanned” but it takes a lot of man-hours to keep it that way. The engine room and machine shop are really clean and well organized―I didn’t see a drip of oil or a smudge of grease.
Right: One of 4 diesel engines that provided the electricity for the ship and run the electric motors that drive the propellers.
Tuesday, March 9, 2010
BotCam – Jake Asher provides the story of the BotCams used on this trip.
Meet the Crew – read about the fun lives of the people making this expedition possible.
It would be easy to start every post with a beautiful sunrise or sunset photo. In this one, you can see Anatahan Island in the background. Just before the sunset, 3 large wahoo were caught. Poke and fried fish are the favorite items on recent menus (breakfast, lunch and dinner).
Right: Steve, Frances and Mills show off their catch.
This photo/diagram shows how sonar waves ping the seafloor and also shows the bathymetric map that is made from the data.
We used the multibeam sonar to map shallow banks north of Farallon de Mendinilla and east of Anatahan and Sarigan. The multibeam work continued day and night and produced huge amounts of data that needed to be processed. I can only sit at the computer for short periods, but the map team members work 10 hour shifts and most of that time is spent processing the data and making new maps. There are always 2 or 3 people processing the data.
Left: The TOAD seen with cameras facing forward.
Monday night, we put out the TOAD (Towed Optical Assessment Device). This camera is towed behind the ship and sends video directly to the control room. We were able to see some of the seafloor we had been mapping. The first run of the camera went for 2.25 hours, covered a distance of 3 miles and went to a maximum depth of 400 feet. The second run went for 3.5 hours, over 4.5 miles to a maximum depth of 300 feet. Towing the camera sounds easy, but someone must be on the controls to keep the camera from crashing into the bottom. The camera needs to be close to the bottom for the best video, but without someone on the controls, it can crash. Driving requires constant attention. Most of the seafloor had a sand coverage with some algae. Occasionally, there would be oohs and aahs over something other than sand and sea weed: sea stars, large sea cucumbers, sponges, sea urchins or the infrequent fish. I really enjoy watching real time video of previously unseen seafloor, but I found myself falling asleep on my feet. I finally had to give up and head to the bunk.
Right: Steve & Viv prepare the TOAD for launch.
Today, we are near Saipan planning to do BRUV work during the day and the TOAD tonight. A nap might be a good plan so I can watch the TOAD through the night, but I don’t want to miss the BRUV action either.
Sunday, March 7, 2010
I AM HAPPY!! and everyone on this ship knows it. Fish 250 was removed from the internet for over 24 hours. I tried to keep a good attitude. I spent the better part of 3 weeks working on this blog. I was able to interact with most of my Guam students via the blog during that time. That was great, but, "I wasn't done!" We came back up this morning and I was dancing in the e-lab. I should be glad I was shut down because coming back up has made me so happy.
Friday, March 5, 2010
Thursday, March 4, 2010
Fishing is everyone’s favorite activity, either for the catching or the eating. The best method is trolling using lures when the ship is traveling at about 10 knots. This only happens when the ship is heading from one study area to another. When using the multibeam, the ship travels at about 4.5 knots and the fish are less apt to bite a slowly moving lure.
Left: Kenji making poke from a wahoo he caught.
Above right: Frances with mahi mahi skins she is drying to make a fishing lure. Before drying she had to remove all the meat and later all the scales were removed. The resulting skin is very tough.
Right: Jonathan on the exercise bike pedaling to Rota. There is an exercise room on the ship with a treadmill, rowing machine and weights. Many of the crew members like the bike best because it’s out on the deck with the great view.
Left: A few of the movies available.
Above: Learning new skills is always fun. Here we are splicing lines to hold buoys. There have also been several knot-tying sessions.
Tuesday, March 2, 2010
We lost half of the science team in Saipan. The fun work of surveying fish populations is over so the AUV, BotCam and BRUV teams have headed for home. A tsunami at sea is not felt by ships, but the tsunami warning came while we were still at the dock. We were alert and ready to depart, but fortunately for us and the entire Pacific, the tsunami didn’t materialize.
Right: The BRIDGE of Farallon de Mendinilla (or is it a tunnel? or a cave? )
The island is small (1.6 miles long by 0.25 mile wide) with only grass and shrubs―not even one coconut palm. There are a lot of birds: frigates, boobies, terns, and other species. We’ve seen whales on three occasions. The ones that were close enough to identify were humpback whales.
The BRIDGE of the Oscar Elton Sette is where the officers drive the ship, plot courses, handle navigational concerns and communications. I’ve had two tours of the bridge and am amazed by the electronics and complexity of each system. Rather than a description, I’ll just give you a few pictures.
Right: The steering wheel is considerable smaller than I expected.
Chart table used for plotting the course. GPS is also used, but charts are kept in case the power fails.
Right: The iridium phone works via satellite. The crew can use it for personal calls during non-business hours (East Coast to Hawaii). That doesn't leave much time but it is also available on weekends.
Sunday, February 28, 2010
"Wirelessly communicating with Autonomous Underwater Vehicles (AUVs) is very difficult―the type of wireless communications that we rely on in our day-to-day lives does not work underwater. Most wireless systems, like WiFi or mobile phones, rely upon high frequency electromagnetic waves―millions or billions of cycles per second. Underwater, high frequency signals are attenuated, or blocked, over short distances. That is part of why when you are snorkeling or SCUBA diving everything looks blue―the higher frequency red light has been blocked out. To communicate with SeaBED AUVs, we rely upon sound waves, which use only around 12 thousand cycles per second. Echoes, other noise, and a number of other challenges presented by the ocean result in us having a very slow connection to the robot. Also, like using a walkie talkie, only one person can be talking at a time. If we are sending commands to the robot, it can't be sending us information. Finally, sound travels slowly through the water, so it takes time for the message to even get to the boat (this is called latency). That all means we have to heavily compress images so that they are very small on disk before we transmit them, and we don't get all the pieces in the right order. Putting together the image ends up being like putting together a puzzle―you have to make sure you have all the pieces, and then put them together in the right order. The compression means that the images look pretty rough, but they still give us an idea of what the robot is doing, and an early glimpse at the seafloor. For the rest, you have to wait until it comes back up! SeaBED AUVs can take over a thousand images every hour! "
OK, me again. Chris will continue working on this project. He wants to make it easier and faster. With this new trick, the scientists will know, while the AUV is still below, that all systems are working and the AUV is taking quality photos.
Saturday, February 27, 2010
Monday, February 22, 2010
The AUV work has gone smoothly. Launching occurs each evening about 8:00 with recovery at midnight. The AUV has 2 cameras, one facing downward to photograph the geography and one facing forward for better fish identification (it’s difficult to identify a fish from the top, looking down). At night the AUV takes only still photographs. A strobe illuminates the scene every 5 seconds and the cameras shoot in synchronicity. A 4-hour trip produces more than 2,500 photographs with each camera. Processing that many pictures is a time consuming job. The AUV also has a CTD and records data for future analysis. Chirs (see Meet the Science Team) is working on a program that will allow the AUV to send pictures to the ship in real time. To date, this has only been accomplished when a ship is directly over the AUV. Chris is very close to success―maybe tonight.
OK, every entry in this blog has been mostly science. For me, that’s the greatest fun. For the next entry, I’ll try for some of the non-science fun onboard a ship.
Saturday, February 20, 2010
The preliminary bathymetric map of Galvez Bank is completed and shown below.
There is a new page on the blog. Click on the page titled, “Mutibeam Sonar.” Joyce Miller gives the basic information on how the multibeam works and how they generate these great bathymetric maps.
We have said good-bye to Galvez Banks and, after a bit of multibeam work west of Guam in the middle of the night, we are cruising towards Rota.
Steve swinging in the long-line pit. This is the area that is used for recovery of the BotCams, BRUVs and the AUV. On other expedtions the area is actually used for long-line fishing as a survey method.
Pet guppies getting some sun and enjoying the view on the ship's deck.
Wednesday, February 17, 2010
Sparky cutting bait
The days are settling into a routine. As the sun rises, the multibean sonar is lifted and secured or Eric turns off the echo sounder he uses for locating schools of fish. By 7:30 A.M., the camera teams are ready with the 2 BotCams and 8 BRUVs. The deployment depths have been determined so each rig is set with the appropriate length of line. The camera batteries have been charged over night (10 rigs make for a total of 20 cameras). The bait has been cut and stuffed into the bait bags. Deployment of all 10 sets takes about 1.5 hours. Each set of cameras runs for just over an hour so as soon as the last cameras are deployed, the first are ready to be retrieved. Retrieval is more time consuming. Each camera set is marked by 2 orange buoys. The ship must approach with the buoys on the lee side (sheltered from the wind ). A crew member then throws a line with a big 4-pronged hook to snag the line between the buoys. If the ship is too close, it runs over the buoys―too far away and they have to come around for another try which can take up to 30 minutes. Generally, the morning cameras are back on board in time for lunch. Afternoons are a repeat of the morning and the cameras are back on board just in time for dinner.
Mills with a mahi mahi
We have a couple of fishing enthusiasts on board. They put out troll lines whenever they get the chance, usually at sunrise or sunset when the captain kicks up the speed to about 10 knots to reach the next study location. There has not been much time for fishing but we have eaten a few mahi mahi. This makes everyone happy―the fishermen of course, and the rest of us for the fillets.
Night time operations with the AUV
After dinner, the AUV team prepares the vehicle for deployment. The AUV is the most time consuming project. They spend hours with the electronics and hours more getting it ready to go underwater. When the communications work, the AUV follows a pre-programmed path about 4 hours in duration. When communications cannot be established, they have to bring it back on board and try again the next night. They have been so busy that we have not yet been able to see their pictures. Soon, I hope. It will be interesting to see the differences between daylight and night time activities on the sea floor.
Monday, February 15, 2010
The past two days have been spent working with the Autonomous Underwater Vehicle. On Sunday, the AUV was put in the water but never set free because it was having communications problems. On Wednesday, it was communicating perfectly, but just as it was to be released, the last line holding it to the ship became entangled and The AUV had to be brought back aboard. The afternoon deployment went perfectly. The AUV stayed on track for about two hours. It brought back pictures and video but I haven’t seen them yet.
There are many different kinds of AUVs. The AUV being used on this trip is called the SeaBed from Woods Hole Oceanographic Institute (WHOI). It can be programmed to fly slowly or hover over the seafloor to depths of 6,000 feet. It is used to gather detailed sonar images and pictures of the seafloor.
WHOI's newest vehicle is the Nereus. Nereus is actually a Hybrid Remotely Operated Vehicle (HROV). It can operate autonomously or by remote control. In May of 2009 it explored the depths of the Marina Trench at a depth of almost 7 miles. This was only the third time man has been able to see the deepest spot on Earth.
AUVs are an excellent tool to explore depths not easily accessible to divers. Although they are expensive and sensitive high tech machines, they are not as expensive as Remotely Operated Vehicles (ROVs) and manned submersibles.