Wednesday, July 16, 2008

Last Day

We were able to get the final 15 archival tags out on small bluefin tuna on Saturday morning, and we topped off the live wells so that 15 fish were aboard swimming in circles below deck. At this point we have archival tagged 112 Pacific bluefin in the past week, and collected 30 live fish for the Tuna Research and Conservation Center. We’ve also placed 7 archival tags in albacore (we stopped tagging albies when I realized how many bluefin were around). This total puts our team at a total of about 550 electronic tags on Pacific bluefin. For the first time in years- all our electronic tags aboard the F/V Shogun have been deployed and there are no more tags left to put out- what a spectacular last weekend. Fishing did slow on Sunday- but we did get some super sized albacore on the trolling rods and we were treated to a rare showing of a killer whale pod near the boat- in albacore country. Our Ph.D students, Nishad and Dan requested a few more yellowfin to sample and sure enough Norm found us some nice sized yellowfin as we headed about 10 miles to the south. With the yellowfin sampling completed our trip was 100% scientifically accomplished. Dan Madigan had requested samples for an ecological isotopic study of California Current tunas. He’s examining the nitrogen and carbon isotopes and literally taking the saying you are what you eat to the research bank. He’s able to examine albacore, yellowfin and bluefin and distinguish who eats fish and who eats the crustaceans, krill and “feed Layer” animals just from taking a small liver and muscle sample. We also took some samples for a mercury content study we’re doing on bluefin. So the final totals are 160 bluefin for science- 30 of these live for the TRCC collections, over 50 samples of albacore and yellowfin for science for Stanford Ph.D students. Its been an inspiring time- and a trip that will go down with 1999- when we conventional tagged over 100 large bluefin-and 2002 when we put out over 130 archival tags. Our science will help to generate the knowledge we need to manage bluefin tuna on the west coast of North America and the data will trickle in from this large scale deployment for years. Scientific papers are under the links that say scientific data or publications. Our gratitude is deep to the crew of the Shogun with Captains Norm and Bruce helping us for years with this remarkable legacy of bluefin research aboard the Shogun. Our scientific team has been top notch and once again- our thanks to our technicians, students and researchers from the TRCC and Stanford University.

Tagging Pacific Bluefin

Epic- Remarkable- Inspiring- Those are words to describe today, Friday, July 11th aboard the F/V Shogun. I’ve not experienced a day fishing and tagging Pacific bluefin like this since early August of 2002- same place, same ocean- but a long time has passed since the bluefin were biting like this. It is a day you live for as an angler- and as a tuna scientist- the fun of such great action keeps you enthusiastic about what we’re doing forever. Bluefin decided to feed today, after they had stayed off the bite on Thursday, and with this-along with some spectacular weather, what had been a trickle of tagging for the first half of our trip- turned into wide open fishing-tagging and releasing effort, as fast as our teams could go. We first loaded up our live wells with 7 additional bluefin for transport back to the Tuna Center- and put a surgery station open sign up on our archival implantable tagging station. Captains Norm & Bruce along with mates Tommy, Patrick, Matt and Randy (our chef) were the anglers who specialize on these long range trips- getting the fish in fast- which helps to guarantee survivorship post surgery & release. The fish were coming into the slings at the swim step where the action for Ty Brandt, Luis Rodriguez, and Alex Norton was as fast and furious as it gets. We spent the morning tagging small bluefin that ranged from 12-20 lbs with the occasional 40-55 lb fish in the mix- they were all lifted aboard the Shogun in a sling of water, measured, tagged and released. When the fishing is this good the scientists (~10 of us) from our team have to remain at our stations to keep up with the line up of fish waiting to receive implantable archival tags. Two green conventional tags near the base of the second dorsal fin- provide anglers and commercial fishers with the advance notice that inside the fish is an archival tag that garners a big $$ reward when returned. A long green Teflon sensor stalk protrudes through a small incision out of the fish- collecting valuable data tracking their movements in some cases tracking individual bluefin tuna as they migrate back and forth across the Pacific 20,000 nm. At one point today-the bluefin were hanging in slings, 3 and 4 deep waiting for surgery but with the steady morning action we trained Mr. Jake Noguiera, TRCC technician, and avid fly fishermen and fly tier who along with long time MBA aquarium veteran Mr. Chuck Farwell led a second station which eased the pressure on Robbie Schallert and myself. At one point every 2 to 3 we had a new tuna in the surgery stretcher- it was continuous for the entire day, with Steve, Nishad, and Dane lifting every fish to the station and Stanford University students, Gen Del Ray and Christine O'Neil along with Dan Madigan kept the surgery stations organized. When we were done- 88 Pacific bluefin were tagged, 6 live ones swam in the wells, another half-dozen samples for a Ph.D students project measuring the genomic and protein expression of bluefin had been landed. 100 bluefin caught aboard the Shogun in a single day- Glad we’re able to say that these fish are here- that they’re biting sardines- and look plentiful at the surface with great action- boilers, jumpers and foamers. Whales, albatross, dolphins and bluefin- what a show.

Thursday, July 10, 2008

Unloading at Fisherman's Landing

We came in with our full load of bluefin, but unlike years past where we usually unload at Scripps dock, we came right in to Fisherman's Landing. Here Norm pulled the Shogun in as close as he could, and we unloaded each fish individually from the well in a sling of water. The hard part was that we had to walk, and run the fish- 400 feet up a ramp- across the dock- and down a sidewalk to get to the Tunabago truck, that has been built specifically for transporting fish. The driver of the truck had done a masterful job of pulling it into the crowded Fisherman's Landing parking lot, and Joe Welch and Ryan from the Monterey Bay Aquarium met every fish- and unloaded them into some cold Monterey ocean water within the truck. The fish lit up immediately and were looking super after their relatively short 12h transport from the ocean. These bluefin circled beautifully in the tank, and the entire load was transported aboard a big rig truck, 8h over land, through LA and up the Interstate to Monterey where they were unloaded successfully into the Tuna Research and Conservation Center tank. All 14 fish in the load (about 12-18 lbs each) survived and were reported to look very good in their new home. Two fish from our prior year's collection are in the tank and will help the new fish learn to feed. We hope later in August to implant heart rate tags in the fish and conduct some research studies on bluefin- the olympians of the sea. We headed back out aboard the Shogun and fished for the latter part of the afternoon-Pilot whales, Risso dolphins greeted us. Hopefully tomorrow we'll find some more fish.

Wednesday, July 9, 2008

Pacific Bluefin Tagged!

The Tag-A-Giant team is currently onboard the F/V Shogun for our annual tagging and collecting trip. After two days in U.S. waters, we're now fishing in Mexican waters where a very nice showing of tunas occurred. Small bluefin were feeding at the surface in numerous spots. Some are the smallest fish we've seen in years- measuring 63-68 cm- about 5kg fish. We were able to collect 16, tag about 10, and then collect 3 for sampling by Ph.D students doing projects on physiology and ecology. It's been a team effort - we're after bluefin from the 2nd year class - fish that are new arrivals from the western Pacific. Catching them can be challenging. We were able to switch to lighter tackle, and sure enough we hooked over two dozen on light tackle.

Bluefin Blitz!

We've had an exciting day aboard the Shogun. We've been in an area that has some very spectacular schools of small bluefin- exactly what we're looking for. Today was an Audubon special with whales, albatross, jumping bluefin- and albacore- sometimes all around the boat. The bluefin are two year old bluefin- about 15-18 lb fish- perfect for collecting- and placing in wells flowing with seawater below the deck. The bluefin made some spectacular shows- at the surface- aggressively feeding, jumping and exciting all of us. We have not seen such intense surface action in two years. Sure enough we slid in on the fish, and both crew and scientists hooked up with live sardines. Our first priority was to fill the wells so that we could transport the bluefin back to Monterey for our Tuna Research and Conservation Center program. There the bluefin will be put through a variety of programs including having a new heart rate tag implanted inside the body cavity. Eventually some might make it to the "show," the Monterey Bay Aquarium's Outer Bay Waters tank where today, bluefin as large as 500 lbs collected 8 years ago by the Shogun are swimming gracefully. Once we collected fish and filled the wells- the archival tagging began. We were able to get out about 8 tags, a great start, all programmed to take high resolution data- at 4 second intervals. Imagine this- every 4 seconds we get ambient light, temperature, pressure and internal body temperature. The data allows us to "see" what a bluefin does from the second he or she leaves the boat. We're hoping the tagged fish will remain in the Ocean for years- with the tag capable of over 5 years or more of data logging. To date, our research team has collected over 50,000 days of Pacific bluefin tuna data with our archival tags, and our research will provide scientists and fisheries managers the basic information required to build models of how the bluefin use the California Current waters. It has been a super day- with inspiring shows from juvenile bluefin- and a scattered albacore bite mixed in later in the day. We're headed in to San Diego with the load of fish, and our team could not be happier.

Monday, July 7, 2008

TGF Team Onboard F/V Shogun

Our annual tuna tagging and collecting trip has begun aboard the F/V Shogun with Captains Norm & Bruce. We left San Diego on a hot and sunny Saturday afternoon, loaded up with live bait, electronic tags, and sampling gear to study tunas for the next 9 days. Our objectives are to collect small bluefin to bring back to our lab- and to continue the archival tagging of live fish with implantable tags. Our trip is part of the Tagging of Pacific Pelagics program ( Together the tuna team at TOPP has deployed over 1000 electronic tags in Pacific bluefin, yellowfin and albacore tunas. The team has focused implanting tags in Pacific bluefin, with over 430 thus far. In addition we've put in over 239 tags in albacore tuna. Our first day out we headed toward San Clemente Island where there had been a sighting of bluefin tuna in the past week. The sea surface temperature charts looked interesting to the south of the island, and we worked a frontal area from the 43 bank up toward the island. Water temperatures were in the range one would expect for bluefin. We were greeted by fin whales and blue whales, as well as schools of bonitos. Our Ph.D students, Dan and Nishad, sampled the bonitos to compare their physiology and ecology with tunas as we continued looking for bluefin to collect or tag. Sure enough on the first day late in the afternoon, Mr. Chuck Farwell sighted some jumpers that turned out to be the one show of bluefin all day. The fish went down and sunk out of sight when we approached the school, but our spirits were high having seen the right size for collecting so quickly. Seas were calm, food was terrific and the entire team looked forward to having a bite. Word of bluefin to the south of us was solid- so we're hoping to head in that direction in the coming days.

Thursday, July 3, 2008

TGF @ Atlantic Bluefin Tuna Stock Assessment

The 2008 Atlantic bluefin tuna stock assessment session concludes its business tomorrow in Madrid, Spain. The Tag-A-Giant Foundation was represented at the meeting by Dr. Andre Boustany, a post-doctoral research associate at Duke University. He presented a paper to the scientific body on the preliminary results of TGF's October 2007 tagging campaign in the Gulf of St. Lawrence, Canada. For pop-ups to date, three of the six tags that remained on fish beyond the onset of the breeding season have popped up in the Gulf of Mexico and three in the western North Atlantic. The tagging data support the hypothesis that strong linkages exist between the Gulf of St. Lawrence fish, the North Carolina foraging grounds and the Gulf of Mexico spawning grounds. To date, none of the fish has a geoposition in the eastern Atlantic management unit (east of 45W longitude). Six additional tags are due to pop-up in the near future.

Drs. Nathan Taylor and Murdoch McAllister from the University of British Columbia presented a new stock assessment model developed with the support of TGF that incorporates cross-over rates of the eastern and western stocks estimated from electronic tagging and chemical analyses of bluefin earbones, or otoliths. By better accounting for the significant percentage of fish from the eastern population that are taken in West Atlantic fisheries, the new model should lead to a better estimate of the number of bluefin tuna from both stocks remaining in the Atlantic Ocean.

The 2008 stock assessment results will be finalized and released in September.