Bluefin finally cooperated today. With a tremendous effort by all involved we loaded up the wells to maximum capacity - it took all day and diligence at every stop. This size class we're collecting are extremely picky eaters. The Shogun crew led by Norm, Gunny, Cha-Chi, Matt, Pat and Randy along with our team had to have extreme patience and perserverance. These fish are very tough to collect. But today on every stop we were able to get 2-4 to bite- we often lost a few due to the reliance on light tackle. A larger class the third year juvenile bluefin were also present- and a half dozen fish were released with tags once they were deemed too large for the wells. All the fish are measured- and the smallest was 26.7 inches (about 10 lbs) and the largest 36 inches - a robust 38-40 lb fish. All the bluefin are in great condition and tonight with a sliver of the moon we're able to watch about 17 swim below decks here on the Shogun. Tomorrow is another day- and we hope to put some archival tags in small bluefin. Tagging for a living and saving the PBFT!
Friday, July 24, 2009
Stealth bluefin fishing
Today we used stealth techniques on bluefin, and sure enough a few consistently bit the sardines. The crew loves to fish for bluefin on this trip- and everyone was on the decks as Norm consistently put us in the large bluefin tuna schools. We opened archival tagging station 1 led by Robbie Schallert and Dr. Barb Block. We were able to deploy 5 archival tags into small bluefin ranging in size from 20-35 lbs. Anglers from the Shogun and TRCC used a variety of newly tied gear which included smaller circle hooks, 25 # test, and stealthly tied knots. The bluefin than proceeded to bite some of this gear along with the typical heavy tackle we used to get fish in quick. However, we also got bit on 40 and 50 lb test raising the point that maybe some of these fish would have bitten anything we put out! But most did not bite at all. They just go down when we go over them- a bit skiddish. We were rewarded today with 5 really nice bluefin for tagging and 3 for collecting. About five more got away either at the swim step- on the first bite or after a long fight. Currently the cut off for tagging is about a 20 lb bluefin- above this size we tag them as they get a bit too large for the wells for collection of live specimens. There are scattered bluefin in the region. Some larger schools of small jumpers, boilers. Our camera crew got some awesome shots with their super fast digital arrays. Weather could not be finer and armed with a tremendous dose of enthusiasm- I hope tomorrow will be the day we get our wells filled.
Thursday, July 23, 2009
July 22nd
The Shogun crew and research scientists spent a day looking hard for small bluefin tuna. We saw remarkable schools of collectable size bluefin tuna in the 10 to 15 lb. range, but we were unable to get a single fish to bite. We had a fantastic film day for our Ocean Futures colleagues filming a bluefin movie on the Shogun for the Cousteau team. It was an Audubon special- bluefin and a few albacore schools, mola, blue whales, Risso dolphins,white sided dolphins, albatross, storm petrels, terns and phalleropes. At least for the film team we put some serious hours in the tape bank. We're pulling together the best hypotheses as to why it's hard to get those small bluefin to bite- you can be sure we're moving to the lightest line we have. One issue going on is the tunas are feeding on anchovy and sauries- which are very small compared ot the sardines - so we're trying swim baits, anchovy,small sardines and iron jigs. Tomorrow should be the day! And hopefully we'll deploy our new miniature archival tags in these adorable sized bluefin!
Wednesday, July 22, 2009
The Tunabago
The combined TRCC-Shogun team had a smooth morning offloading the bluefin tuna. The tuna transport truck "The Tunabago" arrived 9 hours later at the Stanford Tuna Research Conservation Center with all passengers in good condition. By 10am we were headed back out to sea and within a few hours were among dozens of blue whales. Late this afternoon a few spots of tuna made a showing underneath diving terns but maintained their elusive status today. Our group has high hopes for a successful day of collecting and tagging tomorrow.
Searching and Sampling
Today was a beautiful day on the ocean - clear skies, warm temperatures and beautiful weather. We started the day with tremendous optimism after the our first day's success; however, we failed to locate Pacific bluefin tuna, Thunnus orientalis. A highlight of the afternoon was Jim Miller catching a 25 lb yellowtail- his first ever off a large kelp paddy. We did find one lonely albacore on the troll. Dan Madigan sampled the the albacore for his thesis research on diet of albacore. We're going to take the live fish in to the dock to off load for a trip to the research tanks in Monterey. Hope to be back out fishing by the afternoon. We're thinking a lot about how the bluefin tuna interact with the banks of the region and where they might be.
The sampling shows Gen Del Ray and Luis Rodriguez taking fresh samples of the tuna hearts for studies that help us better understand how these olympians tolerate large changes in ambient water while delivering oxygen to tissues that operate at high temperatures. Our heart is warm- and sends blood to warm tissues- the tunas have this remarkable capacity to go deep into cooler waters- chilling the heart- but maintaining flow to warm muscle tissues. How they do this is a mystery given a mammal's heart would stop! Dan is getting the samples from the stomach for isotopic analyses, and Jim Miller is smiling about that first fish in the Pacific.
The sampling shows Gen Del Ray and Luis Rodriguez taking fresh samples of the tuna hearts for studies that help us better understand how these olympians tolerate large changes in ambient water while delivering oxygen to tissues that operate at high temperatures. Our heart is warm- and sends blood to warm tissues- the tunas have this remarkable capacity to go deep into cooler waters- chilling the heart- but maintaining flow to warm muscle tissues. How they do this is a mystery given a mammal's heart would stop! Dan is getting the samples from the stomach for isotopic analyses, and Jim Miller is smiling about that first fish in the Pacific.
Monday, July 20, 2009
Outstanding start to Pacific Bluefin trip
The Shogun has become a Research Vessel for the week as the Tuna Research and Conservation Center team of Stanford University and MBA are out with Captain Norm and the Shogun Crew for our annual bluefin tuna tagging and collecting trip. The trip is supported by our Tagging of Pacific Pelagics (TOPP) program (http://www.topp.org/), a 10-year program focused on using electronic tagging technologies to document the movements and behaviors of marine predators in the North Pacific. The objective has been to advance electronic tagging technologies and scientific methods to meet the challenges of the 21st century for marine resource management and ocean modeling. To date the TOPP team has tagged 4000 fish, sharks, whales, squid, albatross and turtles. The second objective of the trip is to collect bluefin for our research center in Monterey, CA.
Today we got off to an outstanding start on our summer trip as we’ve located some bluefin of the perfect collectable size, about 12 lbs. We quickly placed 10 bluefin aboard the ship in two holds and began tagging with archival tags. This process is somewhat akin to throwing a laptop computer into the bluefin and returning the fish to the sea. This trip we’re carrying the Lotek 2310 archival tags that require surgical implantation and some brand new very advanced tags that we’re testing. The tags record light, temperature and pressure, they have a clock and the algorithms allow us to do position and discern the vertical and horizontal movements of the fish. It’s a great start to the trip to be close to home and have the perfect size fish in the wells for collection. We’ve had a super day with whales, dolphins, bluefin, albatross and terns.
The pictures show Luis Rodriguez and Dan Madigan removing the hook from a fish on a specially built swim step on the shogun for handling live fish. We had two bluefin tagging stations operating where Robbie Schallert and I tagged fish and at the second station we had Jake Noguiera and Alex Norton tagging and they are shown releasing a fish. Gen Del Ray and Dane Klinger assisted.
Sunday, July 19, 2009
The Great Marlin Race
I know, I know. This is a bit off-topic. But the Tag A Giant science team has a long history of tagging all kinds of cool animals. (In fact, Barb put out the very first electronic tag went out on a billfish!) This week, in recognition of the 50th anniversary of the Hawaiian International Billfish Tournament (HIBT), we are launching the Great Marlin Race! Up to 10 teams will have a chance to tag Pacific blue marlins with pop-up satellite archival tags -- and after 180 days, when the tags are programmed to be released, we'll learn whose fish went the furthest!
You can follow the action on a brand new web site (http://www.greatmarlinrace.org/). George Shillinger, a Block Lab Ph.D. student any me will be reporting each day, sending back photos and videos of the race as it unfolds. You can also follow along on our Great Marlin Race blog. Some of the features and functions you'll see there might also show up on the TAG website, and we'd love to get your feedback!
Off to the races!
Thursday, July 2, 2009
Gale Winds of Change
The US government is considering sweeping changes to the way we manage bluefin tuna domestically. The stated goal is to provide US fishermen with greater opportunity to harvest the ICCAT quota while balancing the need to end overfishing of the Gulf of Mexico-spawning, western Atlantic population by 2010 and rebuild the population by 2019.
2003 was the last year that the US caught (or exceeded, as the case may be) its full quota. Since then, we've caught just 15-69% of our quota. Less than 25% of the commercial quota was caught in 2008. Speculations abound about why US landings are at such a low level, ranging from a decreased prey base to decline of the population. Unfortunately, there is a lot of evidence to support the latter.
The new management options being considered are too numerous to mention (click here for the full suite of options), but most of them lift restrictions on harvest to increase catch. The most alarming proposal is to lower the commercial minimum size from 73" to 65". There is extensive scientific evidence that changing the targeted size classes of exploited living natural resources can change the genetic structure and life history of the species. In written comments submitted to NMFS earlier this week, TAG expressed opposition to the proposal to lower the minimum size.
Another concerning proposal is to eliminate the daily bag limit in the commercial handgear fishery. Fishermen can now land up to 3 fish per day. While catching the limit is rare, allowing unlimited retention could be disastrous in a hot fishery, as an entire cohort of fish could be caught due to bluefin schooling behavior. This potential glut of tuna landings would also flood the market, resulting in lower prices and lower profits.
The same (or stricter, in reality) regulations that are now under consideration for weakening resulted in full utilization or overharvest of the US quota up until 2004. Lifting restrictions on the fishery now could have the opposite result of the stated goal of quota utilization. Increased harvest could lead to further population declines, which would lead to even lower catches in the future. And the likelihood of ending overfishing and rebuilding western bluefin tuna would be blown away on the gale winds of change. The good news is that we can rebuild western bluefin by 2019 if we use the best available science to manage them.
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