Image Credit: Center for Environmental Visualizations at the University of Washington, Dr. Michael Wetz, Texas A&M University-Corpus Christi, Deep Sea Systems International, Schmidt Ocean Institute
Research Accomplished aboard the R/V Falkor
This morning the Fisheries Lab Team completed longline sampling and processing fish until noon. After all was complete the team headed to the dry lab on board to begin our summary of the cruise for the evening. The scientists ran statistics for the success of this cruise. Below is a summary.
At 6pm, crew and science teams gathered on the deck for the last BBQ at sea and for a presentation by Dr. Matt Ajemian. Afterward videos and pictures were shown on the projector and we enjoyed our last social aboard the R/V Falkor in the Gulf of Mexico. Tomorrow we will back in Corpus Christi!
With only two days left on this cruise the day's plan included the last CTD casts at site MU-828, and an ROV dive at Great Reef followed by longline sampling at A-7. The Coastal and Ecosystem Lab completed their collection from the last artificial reef site and started preparing to pack up. By early afternoon the seas were calm enough to deploy the ROV at Great Reef. However the visibility was poor due to the nepheloid layer which is the layer just above the seafloor containing lots of sediments. In the Gulf of Mexico this layer is generally significant and is created from a mixture of clay and a silty bottom . The ROV was retrieved after about an hour due to an incoming front. The weather quickly changed and white caps began to appear so the Fisheries Team prepared to ready the gear for fishing. The team deployed longlines at site A-7 in sets and fish were collected including red snapper, lane snapper, and almaco jacks. The weather is expected to be the same tomorrow so the fisheries team will have one last chance to collect fish.
Today began with 4 ft seas and 20 knot winds making it difficult to launch some of the equipment so we began preparing for a micro ROV dive. The plan was to dive two of the ships at MI-616. This time the fisheries team used the bow of the boat to launch the micro ROV and weighted the tether to the seafloor (100 ft). Each dive took about 45 minutes and we gathered great footage of the fish found at these sunken Liberty Ships. This micro ROV has been used at seven different artificial reef sites in the last year by the fisheries team and video will be analyzed to determine the fish abundance that inhabit these reefs and also a count of the total number of species seen. On the last dive we even came across a southern stingray. In the afternoon the fisheries team processed fish samples from the previous day as the CTD team collected samples around MU-A-16. Dr. Wetz and crew are looking to see if these artificial structures impact ocean currents and how that influences the base of the food web.
Megan and Stacey retrieve the ROV
Micro ROV
The team guides Megan
Dave and Judd tie the ROV cable to the ship
Dr. Ajemian and Megan operate the ROV and use a blanket to help shield the light
The first task for the day was a CTD cast at our deepest site on the cruise. As the CTD descended to 1100 meters (3600 feet), Dr. Wetz and crew collected water for plankton samples and to obtain "pure" water for in-lab filtering. Deploying the equipment and gathering the samples took about an hour just to get down to the bottom of the seafloor. Our next plan was to perform an ROV dive at BA-A-132 and longline sampling at the same location.
Lionfish at site BA-A-132
Ironically this morning an article appeared in a Scientific American blog on how busy we have been on this expedition counting fish. The article referenced the use of longlines, searching for lionfish, and exploring the liberty ships. As the ROV explored BA-A-132 we spotted numerous fish species previously seen, but we also observed a few new species including a soapfish and a blue tang. Visibility at this site was the best yet and the ROV was able to survey the entire structure all the way to the seabed with perfect water clarity. Toward the end of the dive the sub rounded the edge of the underwater rig near a pipe hole, and inside was another lionfish similar to the fisheries group's previous sighting (see below). The fish's back was turned facing into the structure when first spotted. These fish are an invasive species introduced into Florida waters and we first documented at the Flower Garden Banks in August 2011. Gradually lionfish are spreading further along the Texas Coast and with few predators and a voracious appetite, they can pose a threat to our natural ecosystems. Drs. Stunz and Ajemian will continue to monitor the abundance and distribution of lionfish as they monitor the artificial reefs off the Texas coast.
Below is a video taken by Dr. Ajemian and Megan Robillard from their latest survey using their micro ROV in September 2012 at Site MU-A-16 (toppled rig) 40 miles southeast of Port Aransas.
Goliath on the Reef aboard the R/V Falkor Artificial reef sites surveyed today in the Gulf of Mexico were abundant with life. Co-chief scientist, Matthew Ajemian sat in the control room with the ROV (remotely operated vehicle) operators, Toshi and Jamie, to direct the dive. As the ROV descended on our first site approximately 30 meters deep, Matt helped guide Jamie to the first designated transect. Before arriving at the reef the first glimpse of life appeared. A school of fish called lookdowns swam in front of the cameras. From the science control room, Megan Robillard and PhD student Judd Curtis began to identify the species and log the times the fish were spotted by viewing the video live on several large monitors from this room. They saw horse-eye jack, large schools of gray and red snapper, creole fish, hogfish, blue and rainbow runners, amberjack, butterfly fish, blue angelfish, barracuda, scamp (type of grouper), and spadefish.
At the end of the first dive the ROV came across a stairwell on the underwater rig and hiding behind it was a very large animal that was immediately identified by Judd. The science control room lit up as the goliath grouper slowly decided to show us a glimpse of his size. Using the built in lasers Dr. Matt Ajemian was able to estimate the size of this fish which was at least 4 feet! After visiting two other sites the fisheries team was able to capture the best video footage they have seen of these artificial reefs and the video will be analyzed further to get a good population count from all sites.
Tonight the crew and scientists gathered outside on the second deck to hear from PhD student, David Tupaj as he spoke about the socio-economics of the Rigs to Reefs Program along the Gulf Coast. After viewing the rigs today the topic of the economics of these structures fit well and after the talk we played video from the dive for the crew to see the massive grouper and all the life on the reef.
Our goals on this scientific research cruise have included mapping artificial reef sites off the Texas coast, surveying fish populations on the artificial reefs using the ROV and vertical longline gear, and examining phytoplankton by sampling the water column using the CTD along multiple transects. Using the map as reference here is what the team has accomplished this week.
CTD
Mapping -
On this leg the team has successfully processed and mapped the following sites:
BA-A-28, MI-616, BA-A-132, MI-A-7, MI-A-85 GR, MI-712, MU-802, MU-A-16, MU-828, MU-776, MU-770, MU-775, PN-A-58, PN-A-72, and PN-967.
CTD -
The Coastal and Ecosystem Lab has successfully gathered samples from the following sites: Transect 1 (4 sites), Transect 2 (3 sites), Transect 3 (3 sites), Transect 4 (4 sites) and Transect 5 (3 sites). ROV-
Micro ROV
The Fisheries and Ocean Health Lab has utilized the on board ROV at site BA-A-28 and gathered HD and 3D video from this site. At site MU-802 the micro ROV was tested off this vessel and captured HD video. Although there was limited visibility, the team gathered the best video from this site to date.
Longline sampling
Longline Sampling -
The Fisheries and Ocean Health Lab used a vertical longline sampling method to gather data from the following artificial reef sites:
BA-A-28, MI-616, and MI-712 and processed the fish collected to gather more information about the fish populations on these artificial reefs sites.
Today, we focused on getting two CTD transects complete. We visited seven sites today and deployed the CTD to gather the water samples and filtered them back in the wet lab for each site. This kept Dr. Wetz and his students, Lynn and Kelsey busy throughout the day and have only two transects left to complete. These data gathered will be instrumental for finding out more information on red tide and its harmful effects each season in the waters off the Texas coast.
Overnight the ship mapped one of the liberty ships at site MU-802. Megan Robillard and Dave Tupaj worked to process the map this morning with marine tech, Nathan. The shot on the left is of the Dwight L. Moody ship used in WWII. In the 1970s, twelve liberty ships used to carry supplies and oil in the war were sunk in the Gulf of Mexico at five different sites to be used as artificial reefs by Texas Parks and Wildlife's Artificial Reef Program. These reefs provide habitat for numerous fish species including reef fish and sport fish and we wanted to take an even closer look.
Late in the afternoon we gathered the equipment to launch the micro ROV (Video Ray Pro4). The challenge of doing this in particular was getting the sub over the side of the ship and into the water because of the rough seas and such a small ROV. Several precautions were taken and the ROV was successfully launched! The crew gathered to watch the feed on the laptop (pictured to the right). A GoPro was mounted on the ROV to capture better video quality. The ROV made it into the water and began recording. Dr. Ajemian maneuvered the ROV around the submerged ship and gathered good video for about twenty minutes. The visibility was not great, but the team was still very happy with the data gathered. The video was downloaded after the dive and the team will be able to determine fish species and abundance, as well as fish size using the lasers mounted on the front of the ROV.
Shortly after a few more CTD casts and ROV clean-up, the SOI team hosted a BBQ on the second deck and everyone got the opportunity to take a break and enjoy the company of all on board. This is an impressive ship but the crew are amazing and without their help in facilitating this research it would not be possible.
The benefit of scheduling = both quantitative and qualitative accomplishments! The day started early with preparing the muster (area on boat designated for our longline fishing) for processing fish samples. As the fisheries team began this task, the CTD team began to prepare to cast the equipment to begin day four's transect. Dr. Wetz's team of students were prepared and given the opportunity to handle the lines for the CTD equipment and even helped to guide it back to the deck. Watch the video (to be loaded soon!) here to show just how impressive this feat was.
Raising the CTD from the last cast
In the afternoon, we decided to have our science at sea seminar early in order to accomplish more fishing at the next artificial reef. Immediately after the talk the CTD crew headed out to enjoy a lecture given by Dr. Matthew Ajemian on artificial reefs. The crew was interested to hear about this research and asked several engaging questions.
At 4:00pm the fisheries team was given approval by the Captain to begin fishing at artificial reef site MI-712. After 4 drops at various locations the operation was done. We quickly paused for a quick bite and afterwards met back to resume the clean up process. Once all was clean we meet in the library to review the day and plan for the next.
With clear skies at 4am the day began with a CTD cast at the start of the first transect. Throughout the morning the ship headed landward and at 3 additional sites the CTD was deployed and successfully gathered data to be analyzed in the lab. Lynn also got the opportunity to handle the lines on deck with direction from the crew. By 11:30 over fifteen samples were successfully drawn and the operation completed.
ROV
Shortly after 2pm the team was ready to start the ROV dives. As the crew was ready to send the ROV into the water a rainstorm brought gusty winds and deployment was delayed. After waiting on the rain to cease and some technical difficulties with communication between the ROV and the ship the dive was cancelled. The other option to make the best of the inclement weather was to gather data from our longline surveys. The team was not scared to fish in the storm (no lightning!) and they got on their rain gear, gathered the equipment, and headed to the muster area to begin sampling. Eighteen fish were caught including a very large gray snapper, a gray trigger fish, and several sizes of red snappers. With the exception of two fish that were tagged and released the others will be processed tomorrow morning.
Dr. Michael Wetz
In the evening we began our science at sea talks for crew and scientists. At 7:30pm immediately following dinner we meet in the library for the first talk of the series presented by Megan Robillard, who spoke about many of the other research projects going on in the Fisheries and Ocean Health Lab. The crew however had a surprise in store for one of our scientists and much to his surprise after everyone gathered, the cake was lit in the hallway and brought into the library as the Happy Birthday chorus resonated. This is the first birthday Dr. Wetz has had at sea and as he thanked the crew he noted how this would be a very memorable one for him, so happy birthday Dr. Michael Wetz!
Today we started with an ambitious schedule making it to BA-A-28 by 7:30am. Our marine techs, Nathan and Jimbo mapped MI-616 and BA-A-28 creating images for ROV operations. During the map processing Dr. Wetz and crew performed a CTD test run in the morning.
Shortly after lunch we began our first long-line sampling, where scientists drop a line with 10 hooks to the bottom to sample fishes using the artificial reef structures. On the second drop we began catching fish. We pulled up a sharpnose shark, almaco jack, and several red snappers. Each fish was measured and weighed and later further processed by taking their gonads, otoliths ("ear bones" to estimate age), fin clips for genetic analyses, and muscle plugs for stable isotope analyses by the fisheries team while the ROV was deployed.
As the ROV made its way to the first reef on BA-A-28 the science control room burst with excitement from both crew and scientists. The video captured was not only in high definition but also in 3D and this vertical rig was abundant in both sport and reef fish. Megan Robillard quickly began identifying and logging the best footage they now have for this project. After surveying the first reef the ROV headed over to the second structure which was a rig laying horizontal on the sea floor. Although visibility was good fewer fish were reported at this structure than the first one. Jimbo, the marine tech, was still very excited though. He even said when he returned home to the UK he would buy a 3D television so he could relive the experience!
After a late lunch and break the team geared up again to resume fishing. After six more casts at BA-A-28 we caught 15 more red snapper and one rock hind. Several of the larger snapper experienced barotrauma as shown in the picture. When you release these fish it is important to vent them (release the pressure in the fish's swim bladder) to increase their survival after release. The fisheries team is also studying the best ways to do this. The fishing ended at 7:00 and after dinner we returned to process the fish samples and clean up. It was a long but successful day and after discussing plans for tomorrow the CTD team will be ready by 4am to begin work on their first transect sampling water at 5 locations going from offshore to inshore.
The voyage began at 10:30 am today as we left the Port of Corpus Christi and headed to Port Aransas, Texas to begin fueling. For this 272 foot research vessel it is no small task to dock this size vessel however our captain Heiko Voltz is one impressive navigator making this difficult task look easy. Before our voyage however, this morning started with a safety training class followed by a fire drill. Our safety training was taught by one of our bridge officers, Thiago Da Silva and student Chas Downey volunteered to wear the immersion suit for demonstration. What a sport! Following the meeting, alarms sounded and quickly life vests were distributed along with the immersion suits for protection.
By 7:14pm (congrats Judd- who estimated this time within seconds this morning) we headed out past the jetties off Port Aransas, Texas on the way toward the farthest artificial reef sites (MI-616 and BA-A-28). The hard work starts tomorrow and everyone is eager to get dirty. Check out more pictures on our Facebook page.
