Sunday, December 14, 2008

Carolina Bluefin Blues


TAG 2008

This is the time of year when the Carolina bluefin show- and the word so far is a few fish have made it down there, some big ones- but the show of fish thus far - is currently below the major years which we experienced- in the mid 1990s. Perhaps in January things will pick up. For the bluefin- I hope so- but I am getting worried.

For bluefin tuna 2008 has not been a good year as ICCAT the commission that is suppose to consider its scientific advice as it makes management quota decisions, has once again shown its unable to prevent overexploitaiton, overfishing, and the demise of Atlantic bluefin.

So much is at stake- the biodiversity of the species, the stability of the populations, the future of Atlantic bluefin as a species. I read a paper today entitled "Predicted extirpation of the dominant demersal fish in large marine ecosystem: Atlantic Cod in the Southern Gulf of St. Lawrence." It is in the latest issue of the Canadian J. of Fisheries and Aquatic Sciences Journal as a Rapid communication. Basically it says that even in the absence of all directed fishing, this animal, once the most prominent fish in the demersal ecosystem as late as the 1980s, has little chance of recovery. Extirpation was described as less than 1000t of spawning biomass, or less than 0.3% of the average spawning biomass in the 1950s. Elevated natural mortality seems to be the problem. It happens when there is a major shift in the baseline of the ecosystem, sort of the tipping point in the ecosystem- where now- so much has changed that the cod cannot recover. Why the cod cannot return here is complex but the basic premise is there are too few spawners- we took too many, and too few juvenile fish to prevent predation from replenishing the ranks

I often wonder how far we'll push the western bluefin tuna that spawn in the Gulf of Mexico- the fish I think of as true Giant Bluefin. I've been thinking a lot lately about what was the virgin biomass - of western bluefin when I was born. How far down are we now- and can the fish actually recover. I often wonder what folks 30 years from now will think of our generation of biologists, fisheries scientists, and managers. We have all the indications- we're moving beyond where we should be- into cod territory, for western Atlantic bluefin to recover, and eastern bluefin are following closely.

I only can retain hope for bluefin in the fact that our team from TAG A Giant has recently shown that the biodiversity in the genetics of the Gulf of Mexico bluefin suggests that if we stopped fishing today- we'd actually be able to retain significant genetic biodiversity from the original virign population- that is much of the original genetic biodiversity- is potentially still swimming on Earth today- in the great, great, grand children (3 or so generations removed) of the original virign Gulf of Mexico bluefin tuna (remember they have 30+ year lifespans, 12-14 year generation times, and it was only in the 1960s we began taking out all the spawners)- so, I believe- its still not too late. So we keep trying to put the facts on the table-paper after paper, and I agree with my countrymen- my local fishers from my native New England- that we do need Europe and Japan to start paying attention- to the fact that they are catching our recovery- that the consumer demand is too high. We too must also pay attention that the Last Giants ply our waters today- and every fish counts-for example how come we gave more quota in the Gulf of Mexico to western Nations. If we can't catch it thats OK- more spawners will make it. If you follow the cod trajectory this is not a good idea. So in this year of our much sought after 1000th Tag Event, and the remarkable new story on Otoliths we've published in Science in October, on how we use ear bones to provide evidence of the birthing place of individual fish- its time we hope that someone listens. Our North American stock is unique, we must do what we can to protect it.

Please Join Us - Sign Up in Support of TAG's team today: www.tagagiant.org

http://www.tagagiant.org/Donate.shtml

We need your help now to Ensure the bluefin's future! Better Yet come join us on the water in Carolina- In return for a donation you can fish with us aboard the Sensation with Captain Dale Britt

Thanks for all your support. Happy Holidays- Barb

Wednesday, December 3, 2008

ICCAT: Another Year, Another Disappointment

The 2008 ICCAT meeting concluded last week in Marrakech, Morocco. The media had been buzzing about bluefin tuna in the weeks leading up to the meeting, particularly in regards to putting an end to the egregious level of illegal overfishing in the Mediterranean Sea. The European Union (EU), the most flagrant abuser of current regulations, said that “time is running out to save the bluefin tuna stock from collapse” and committed to “champion bold and decisive measures” at the meeting. Several nations, including Japan, proclaimed that without meaningful and resolute action by ICCAT, Atlantic bluefin tuna management would be transferred to CITES, the body that regulates international trade of endangered species – and a highly feared adversary of anyone involved in commercial exploitation of an animal or plant species.

Despite all the hype, by the time the dust settled in Marrakech, it was business as usual for ICCAT. The EU was up to its typical antics, maintaining a veil of secrecy on its eastern bluefin proposal until the final days of the meeting. Despite calls ranging from a moratorium, as suggested by an external review panel commissioned by ICCAT, to a 15,000 metric ton (MT) quota, as recommended by ICCAT’s own scientists, the eastern quota was only reduced from 27,500 MT to 22,000 MT for 2009, with a further reduction to 18,500 by 2011. Equally problematic, ICCAT also failed to close the Mediterranean spawning ground for the months of May-July as urged by scientists but instead extended the existing closure by a measly 2 weeks. There is some hope that the new regulations will improve compliance, which, if true, will be more meaningful than any potential quota reduction given the current level of illegal fishing. However, given the fishery’s current operating climate, we’ll believe it when we see it.

The western Atlantic quota was reduced from 2100 MT to 1900 MT for 2009 and 1800 MT for 2008, a change in line with the scientific advice. Yet another ICCAT meeting where our fishermen will follow the science, even if it's a sacrifice, and those in the East will ignore it. As part of the negotiations, Canada was assured transfer of U.S. and Mexican unharvested quota, which will likely result in a comparable harvest level for Canada (and perhaps the entire western Atlantic given recent U.S. underharvests). In a positive development, rollover of underharvest will be capped at 10% by 2011; if a population is so depleted that the allowable take can not be harvested, it is dangerous to add that unused quota to the following year, further threatening the population. The most alarming provision of the new regulations potentially opens a loophole for Mexico to increase fishing mortality on bluefin on the Gulf of Mexico spawning grounds. We are already working to reduce mortality in U.S. waters of the Gulf; this is no time to launch a new fishery in the western bluefin’s most critical habitat.

The U.S. and other Atlantic fishing nations have until June 2009 to implement the new regulations. Hopefully the media and stakeholder groups will keep bluefin in the spotlight and demand accountability. Given the lack of progress, preparations for a CITES listing will undoubtedly proceed in parallel to efforts to implement and enforce the new measures.

Wednesday, November 26, 2008

Block Interview Airs on BBC Radio Program "World on the Move"

On Tuesday, November 25, BBC Radio 4 aired a recent interview with Dr. Barbara Block on tuna research, as part of their "Great Animal Migrations" program. You can listen to the broadcast in its entirety here, or hear an edited version accompanied by some slides by clicking the video link below.

video

As usual, the BBC team did an exceptional job -- asking smart and interesting questions. It is always a pleasure to work with them, and we're glad to have their help in getting more people thinking about these animals and the issues they face!

Monday, November 24, 2008

Rick Rosenthal Working with TAG on Tuna Documentary

On Tuesday, Nov. 18, Emmy award-winning cinematographer Rick Rosenthal filmed bluefin and yellowfin tunas in the Monterey Bay Aquarium's spectacular Outer Bay Waters exhibit. Rick is working with Tag A Giant to create a new documentary film about tunas, and our work to understand and protect them. Rick also filmed our team tagging bluefin off the coast of Canada in October, and will continue working with us in the months ahead to gather all the footage he will need to tell our story.

video

During his career, Rick Rosenthal has filmed some of most challenging wildlife subjects on the planet. His BBC/PBS film Hunters of the Sea Wind was the first major broadcast program to showcase the wildlife of the open ocean. Since then, Rosenthal has filmed over 35 programs, including three award-winning one-hour programs on the great whales, Riddle of the Right Whale, Humpback Whales and Sperm Whales Back From the Abyss, which he shot and produced for the BBC, PBS and the Discovery Channel. He was a principal cameraman for the Blue Planet series and the feature film Deep Blue. His cinematography work on BBC’s current blockbuster series Planet Earth is airing now. Rosenthal’s latest work Superfish, a natural history of billfish, will air on the PBS and BBC networks. Rosenthal has written and published 45 scientific papers, reports and popular articles on marine biology, ecology and animal behavior. He holds advanced degrees from California State University at San Diego and Scripps Institution of Oceanography.

Sunday, October 26, 2008

GRANDERS ON THE DECK

TAG team CANADA Continued the remarkable story of big fish with 6 more Canadian Giants tagged and released. The TAG boat and the
catching fleet worked together transferring 6 fish from the boats to the Bay Queen IV. The team worked together where every boat in the TAG Fleet contributed with a fish for transfer and we succeeded tagging 2.5 Tons of fish several measured in the1000 # class. The Tags are set for 240-300 days- We hope to see where these fish go to Breed. Dr. Steve Wilson and Aaron Spares are leading the charge and the picture above shows Dr. Steve tagging a big one. Aaron, Sheldon (near the hose), mate Mike and Captain Pete are helping on the deck. The fishers of Nova Scotia and PEI are doing the hard work of catching and transferring the fish. More quota has been allocated, when its all captured- we'll be back out tagging- Barb for Dr. Wilson Go Steve!

Saturday, October 25, 2008



Canada Hits 1000!
1,000 TAGS REVEAL MYSTERIES OF GIANT BLUEFIN TUNA

A giant Atlantic bluefin tuna weighing more than half a ton had the honor of being fitted with the 1000th electronic tracking tag placed by our team on an Atlantic bluefin when it was caught and released on Monday (October 20) in the Gulf of St. Lawrence off Port Hood, Nova Scotia. The prized fish, which measured 10 feet in length, was tagged by our scientific team from Stanford University, Dalhousie University and the Monterey Bay Aquarium, working in collaboration with Canadian fishermen from Prince Edward Island and Nova Scotia. The field team was led by Drs. Mike Stokesbury of Dalhousie University and Steve Wilson of Stanford University. Mr. Aaron Spares was also on board helping to tag and lip hook the fish. This is the 5th tag deployed this year from our Canadian squad who also succeeded in the past weeks putting out some acoustic and archival tagged giants. The tunas this week are getting only the Pop Up Satellite Archival tag- build by Wildlife Computers who have been large supporters of the TAG effort.

The TAG team has been tagging bluefin tuna since 1996, when the first tag was put out on a bluefin tuna off North Carolina’s Outer Banks. We have traveled from the Gulf of St. Lawrence to the Gulf of Mexico and from Ireland, to Corsica and to Spain to tag Atlantic bluefin tuna. Placing 1,000 tags on giant bluefin has been a long quest for TAG researchers, whose work has helped to reveal the life histories of these amazing, elusive creatures. The tagging data assembled by the TAG researchers have been vital in identifying how populations of bluefin tuna use the North Atlantic, leading to new discoveries about their physiology, their migratory patterns and their population structure.

I would like to thank all those responsible for helping us to achieve the Herculean task of deploying 1,000 electronic tags on giant Atlantic bluefin tuna, with special recognition of our Gulf of St. Lawrence team who realized the goal: the captains and crew of the F/V Angel Brailyne, F/V Bay Queen IV, F/V Carrie Anne II, F/V Gail O’ Wind, F/V Neptuna, F/V Nicole Brandy, and F/V North Lake Breeze, together with scientists Dr. Michael Stokesbury, Dr. Steven Wilson, Robbie Schallert, Jake Noguiera and Aaron Spares. Special thanks for the support of Dr. John Nielson from Canada’s Department of Fisheries and Oceans. Our gratitude to Captain Dennis Cameron for letting us use his vessel with a super fine door- for tagging. Funding was also from the TAG A Giant Foundation, the Monterey Bay Aquarium Foundation and NOAA. Congrads to our entire team. Go TEAM CANADA!!!

Monday, October 6, 2008

In Search of Canadian Giants

Submitted by scientist Robbie Schallert

The TGF team descended once again on gorgeous Cape Breton Island, Nova Scotia in search for the Giant Bluefin Tuna, and by September 20th five of the TAG boats were on the water. We decided to take advantage of the brief commercial season closure, and it didn’t take long for the first tuna to bite. Unfortunately, we were reminded just how hard tagging Giant tuna can be…after a long fight, with the fish almost to the lip hook, the hook pulled out. For a second, as the tuna hovered at the surface just off the transom, the team scrambled for an over-the-side pop-up tag in a last ditch effort to anoint this beauty with the first tag of the season. In a flash, the fish turned and rushed into the abyss. What a sight to see such a fish…absolutely close to the record! We were concerned about how on Earth we would have gotten it into the boat.



Our spirits still high and the fleet still optimistic, we continued the next morning on the quest for the first Canadian bluefin of 2008. Captain Dennis Cameron and mate Sheldon Gillis aboard the Bay Queen IV guided the TAG boat out of Port Hood, first stopping to jig up live mackerel, and then stopping to pull a small herring net just to make sure we had all our bases covered. After a full day of searching, those two words that make any fisherman’s blood pump…”Hook Up!”…crackled over the radio. North Lake Breeze was hooked into a 300-plus lb fish, and the TAG team scrambled to get the gear ready. The veteran Dr. Mike Stokesbury chose his lip hook and positioned the tuna mat, while making sure the flow of the hose had the proper pressure to ensure the gills would be adequately oxygenated. Dr. Barbara Block checked the tags to make sure they were on and deployable. Once the TAG boat reached the fishing vessel, a delicate handoff of the rod took place. It sounds easy, but with 5 foot seas, a 25 knot wind, and a Giant bluefin on one end, it takes fishing experts to accomplish such an inter-vessel transfer of rod and fish. Sheldon continued the fight, and after a relatively brief battle, the fish was at the leader. To see these guys fight a fish for an hour and then wire the fish effortlessly makes anyone watching feel tired! Dr. Stokesbury had the quickest lip hook to date, and the beautiful bluefin was safely on board. The fish measured over 78 inches, and Dr. Block zoomed into action. This fish got an acoustic, a pop-up, and an archival tag, and the first triple-tagged fish of the season emphatically kicked its tail back into the ocean. While we have not traditionally deployed many acoustic tags, there is a new effort called the Ocean Tracking Network that is establishing acoustic listening stations up and down the East Coast of North America. The acoustic tag on this fish will communicate with the listening stations to let us know its location whenever it is near a station.


The next day brought just as much excitement, as the team again waited with baited breath for its first call to duty. Just like the day before, on a changing tide, the silence was interrupted. This time it was the Angel Brailyne that got her hook in one. A beautiful fish measured at over 90 inches and estimated around 600 lbs because of the girth. You couldn’t have asked for a more picturesque scene…just as the fish was turned loose with its two tags (pop-up and archival), the sun set on the horizon to create one of those magical moments you remember forever.

Third Scientific Technique Confirms That Discrete Western and Eastern Bluefin Tuna Mix on North Atlantic Foraging Grounds

Tag-A-Giant Foundation Scientific Advisor Dr. Barbara Block is co-author on a new paper published in the prestigious journal, Science, entitled, "Natal Homing and Connectivity in Atlantic Bluefin Tuna Populations." The paper was published online on October 2nd and will appear in print later in the month. The study corroborates previous electronic tagging and genetics work conducted by the TAG team and others that there are two unique populations of Atlantic bluefin tuna that do not interbreed but mix on foraging grounds in the North Atlantic. This is the first research to quantify the level of mixing based on feeding area.

The paper analyzes the chemical composition of bluefin tuna otoliths, or earbones, to determine whether individuals were born in the Gulf of Mexico or the Mediterranean Sea, the only known spawning areas of western and eastern Atlantic bluefin tuna, respectively. Otoliths incorporate carbon and oxygen isotopic ratios unique to the waters in which the bluefin swims, creating a birth certificate of sorts.

Otolith samples were collected from bluefin in the Gulf of Mexico, Mid-Atlantic Bight, Gulf of Maine and Gulf of St. Lawrence in the West Atlantic, as well as the Mediterranean Sea. The results reveal a high level of mixing of Gulf of Mexico and Mediterranean Sea-spawned juvenile fish on foraging grounds in the mid-Atlantic. The percentage of Mediterranean fish decreases in the older age classes of larger fish. Interestingly, the research also shows that bluefin in northern New England and Canada are nearly entirely of Gulf of Mexico origin, suggesting that these waters may represent critical foraging habitat of the smaller, more vulnerable population that spawns in the Gulf of Mexico.

Nearly 100% of bluefin sampled on the Gulf of Mexico and Mediterranean Sea spawning grounds were found to have been born in the same area, revealing an extremely high rate of homing that exceeds the fidelity of Pacific salmon to their natal streams. This is not surprising, given previous genetic results that no more than 1 bluefin per generation (~5 years) can transfer to the other population and interbreed to maintain the observed level of genetic difference.

The research has several implications for management of bluefin tuna fisheries and is particularly timely since the international rebuilding plans for Atlantic bluefin tuna will be revisited and likely revised at the ICCAT meeting in Morocco next month. First of all, mixing rates that exceed 50% for juveniles in the Mid-Atlantic Bight confirms that the U.S. fishery is highly subsidized by fish from the eastern Atlantic population. As the eastern population has declined due to egregious levels of authorized and illegal overfishing, the depleted status of the western population has been highlighted as evidenced by the inability of U.S. fishermen to catch our quota. It is clear that current estimates of the eastern and western population size are inaccurate, and only by incorporating realistic rates of mixing in stock assessment models will we be able to reliably assess the populations.

Furthermore, while the overfishing in the Mediterranean Sea is not negatively impacting the Gulf of Mexico population, it is negatively impacting U.S. fisheries and may be largely to blame for the decreased catches in U.S. waters in recent years. This latter point should help the U.S. leverage their voice in management decisions for the Mediterranean fisheries, even if U.S. boats do not fish bluefin in the area.

Lastly, the study has shown that fish in the Gulf of Mexico, Gulf of St. Lawrence and Gulf of Maine are almost entirely from the vulnerable Gulf of Mexico population, highlighting the importance of recovery and protection efforts for bluefin tuna in these regions.

For more information, click here to visit the Tag-A-Giant Foundation page dedicated to the paper.

Tuesday, September 30, 2008

An angler’s perspective on trench warfare

George Shillinger provides an angler’s perspective on tuna tagging research.

I thought that it might be exciting for our readers to provide an angler’s perspective on the fishing and tag deployment experience off Greymouth, New Zealand. I received the following email from angler, Tom Thomson, who is featured within my birthday bluefin blog in this series, regarding our trip on Aug 27-28, 2008.

Christchurch, New Zealand Angler Tom Thomson reports to George Shillinger about his experiences on the Cerveza 2:


Monday, September 22, 2008

Hi George,

Great to hear from you….

We all arrived back very tired on the Thursday night and I found it really tough trying to keep my eyes open for the 3 hour trip back to Christchurch whilst the other drifted in and out of sleep. We had probably one of the most memorable fishing trips we will ever experience and they are still raving about it.

We had some of the fish in a raw state but most of it has been smoked and vacuum packed and it is amazing how many friends you have at times like this. The general impression is that is the best smoked fish we have ever had.

The guys who I brought with me were Craig Tapling, Murray Knight, and Steve Muldoon. In the photo below, Murray is on my left, Craig is beside me and Steve is crouched down beside the fish.


Figure 1: Anglers Murray Knight (left), Tom Thomson (center), Craig Tapling (right), and Steve Muldoon (kneeling) crouch alongside their giant bluefin. (Image: Deckie Redz)

We fished in the order, Craig (broke off after 10 mins when the reel parted company with the rod under the pressure), Murray (about 2.5hrs), Steve (about 2 hrs) and then me(3.25hrs). Murray's was probably the biggest I think and broke off, like Steve's at the leader while trying to get tags in place. We believe that most of them were around the 250kg mark which is fairly average for the area.


Figure 2: A bluefin about to be released from the trace. (Image: Tom Thomson)

Their fight times were around the 2 hour mark but fish were coming in green and full of fight and causing an immense amount of pain to the deckies. I decided to try and tire my fish out a bit more so that we had a better chance of tagging and releasing him, hence the 3.25 fight time.

I've nicknamed mine 'GT' because he was ultra high performance and is derived from our initials (George and Tom). I've assumed that GT survived the next few days as you mentioned the tag would release if he didn't move for 3 days so I guess we now wait for your next birthday and hope the tag pops up and down loads the information as expected.


Figure 3: Heading for home on the Cerveza 2 (Image: Tom Thomson).

Our group is loosely associated through our jobs and this trip was the culmination of a year's planning. We have all been game fishing before but agreed that this is unlike anything we have seen or experienced and is a once in a lifetime adventure for most of us. Craig and Steve came down from Auckland and Murray and I are from Christchurch.

What other information would you like?

I'm interested in any information you may have on GT and his(her?) exploits.

Kind regards

Tom

Tuesday, September 23, 2008

Third Week Tagging Giant Pacific Bluefin in New Zealand

Latest news from the New Zealand tagging team. Entry submitted by Tim Sippel.

After two intensive weeks of fishing, the 2008 bluefin tuna satellite tagging program had made good strides towards the goal of deploying 25 pop-up satellite tags. Although New Zealand’s winter weather hasn’t been great this season, we’ve managed to tag 21 bluefin by the end of August.

The first week of September brought a spate of unpredictable weather, making it difficult for several days to figure out when to go out again. On September 4 the call was made to go out for another charter with Captain Chinner, and crew Josh, Bryce and Andrew aboard Cerveza II. The west coat of New Zealand is dotted with numerous fishing ports that require crossing over submerged sandbars. Greymouth is one these ports, and its bar can be troublesome for even the most seasoned and confident skippers. On this trip, Chinner’s unrivalled experience and iron clad confidence navigated us through a gauntlet of white capped waves that would have chased many other skippers back to the docks.

Figure 1. Cerveza II leaving for a bluefin trip from Greymouth’s harbour greeted by ocean waves across the local sandbar. Photo: Pete Idoine


With those obstacles behind us we motored for the hoki trawlers, about 35 miles offshore. However, the unpredictable weather was worsening, and not improving as forecasted. By nightfall winds were up to 35-40 knots and conditions weren’t fishable, so we hunkered down and stopped fishing for several hours to let conditions ease down again. When things settled back down we moved back to the hoki trawlers and put lines in the water. After a few hours we hooked up, and the fishers who chartered the boat got the one they wanted for ‘kai’ (Maori term for food) to share with family and friends upon returning to port. One +200kg plus bluefin provides a lot of kai for a lot of people, so the next was to be satellite tagged. In the early morning of 5 September we hooked up to a bluefin to be satellite tagged. With a chop still on the water, deckies Josh and Bryce got the fish to the stern. However, the leader clipped the boats trim tabs in the process, and was frayed and weakened as a result. Within mere seconds of tagging this fish, the weakened leader broke and with a swift kick the bluefin disappeared. After being battered for much of the last day on the water, it was particularly disappointing to loose this fish, but that is the nature of this work.

After putting in a few more hours of unsuccessfully trying to hook another, it was time to head back. As we headed in the weather finally eased back and the trip back was swift in the calmed seas. Thankfully, the charter Oracle was headed out for a new charter at the same time we were returning. Oracle’s skipper Mike Boswell generously agreed to let me ‘tag along’ on his trip too.

Oracle takes a different approach to bluefin fishing by using only stand-up gear instead of the more commonly used fight chair in New Zealand’s big game fisheries. Oracle arrived at the hoki trawler ‘Rehu’ in early evening and lucky angler Peter Idoine was the first to hook up soon after his line was wetted. Pete had never been big game fishing before (although had caught some yellow tailed kingfish previously). Learning to gamefish for the first time by using stand up gear on giant bluefin is akin to introducing someone to the rodeo by strapping him straight into the saddle with a bronco. Pete proved to be a natural and showed great poise in bringing his fish to the boat in just over 2 hours though.

Figure 2. Pete Idoine battling his first bluefin, with Tim holding onto the back of his belt for good measure, and deckie Aaron looking on in the background. Photo: Pete Idoine


With Pete’s fish landed it was time to chase another for tagging. As the clock stroked 11pm on the night of 5 September, line began screaming off of the reel again as we’d hooked another bluefin. We had no clue what was in store for us with this fish though. When using stand up gear on bluefin, it is not uncommon for the fish to outlast more than one angler, requiring the rod to be passed to fresh legged fishers. However, it is less common for one fish to outlast 8 anglers and wreck at least 4 different gimble belts over a 12 hour period! It was as if the beast hooked on the end of this line was Michael Phelps embodied as a tuna if you considered each of the 8 anglers he beat a gold medal in the gamefishing Olympics!

Anglers Peter, Grant, Peter, Yab, George, and Tom lined up to take turns battling this fish. When passing the rod from one angler to another, it took all hands on deck to unseat the bent rod from one anglers gimble belt and reset back into the next angler's gimble belt.

Figure 3. Four people struggling to unseat the rod from the anglers gimble belt so it can be passed onto the waiting angler behind while the bluefin continues his unrelenting battle. Photo: Pete Idoine


Around 5am I went for a nap as there were no signs of this fish surfacing soon. I awoke around 7am to fresh sunshine and angler number 5 online with this same fish and no indication that it was anywhere near as tired as the 4 other guys who had taken turns online with it. Eventually angler 5 relented to angler number six who eventually relented to anglers seven and eight, who were actually two guys who’d already been online with it in the previous night. Finally as the clock passed 11am this bluefin surfaced and George (man number eight) dug deep down to get it to the stern. And then as suddenly as this fish was initially hooked, it just as suddenly flicked it tail, catching the line on the boat’s hand rail and snapped the line. After more than 12 hours this bluefin was gone in less than a second!!! An exhausted disbelief fell upon everyone aboard, and the decision was made for everyone to get some sleep. Everyone was spent, and we needed to recoup for a second night of fishing.

We awoke in the late afternoon and chugged back to the hoki trawlers for another go at luring a bluefin online with a yummy piece of defrosted hoki. Although I was on the boat to tag fish and was not anticipating catching one, the anglers wryly told me I’d have to share the pain in catching the next fish if I could have a chance to tag it. I agreed as I was there to tag and was the only non-crew member there who hadn’t been online with the 12 hour beast. After dark we hooked up our 3rd fish which was initially fought by two anglers who were still weary from the 12 hour battle. Angler 3 was me, so the gang converged to help pass the rod over. The heat was on both literally and figuratively as I could feel my thighs burning and I had been at sea for roughly 50 hours without tagging a bluefin yet. Thankfully, this fish capitulated to the stern in 45 minutes, but to my dismay the decision was made to keep it instead of tag it. Nevertheless, I am grateful to the anglers for allowing me to join them on the trip they had chartered. It was a privilege to experience a giant bluefin on stand up gear. Everyone, including the anglers as well as captain and crew of the Oracle are first rate!

Figure 4. Tim hooked up with Tom anchoring the back of the gimble belt. Photo: Pete Idoine

Oracle’s mission was complete, but yet again as one charter completed, another was about to begin. Chinner happily agreed to take me along on his next charter again, so I immediately joined them for another try to tag bluefin with one of the four tags remaining to be deployed.

Reuniting with Cerveza II was welcome under the settled and more favourable weather than the last trip. The charter on Cerveza this time was a group of farmers from outside of Christchurch who’d come to experience bluefin fishing and likewise bring a bit of kai home. I explained what the project was about, showed them some satellite tags, and explained the value of this research. Once they’d landed a fish to bring home, they were happy to allow any others to be tagged for this research. Cerveza II and numerous other boats in this fishery have a policy of no more than one bluefin landed per charter to ensure they are also contributing to the equally rewarding pursuit of tag-and-release fishing. By the early morning of 7 September we hooked up to another bluefin. After a relatively short 30 minute time this bluefin was calmly lead to the stern by wiremen Josh and Andrew and after more than 65 hours at sea this time out, the 22nd bluefin of the project was satellite tagged. At an estimated 250kg, it was quickly tagged and upon release it swam away with a calm flick of its tail. At 4:50am, a few hours after releasing that fish another was hooked. It was a livelier bluefin than the last and it was online for 50 minutes before Josh and Andrew brought it to the stern. They positioned it perfectly for a solid tag shot. And with that, this bluefin estimated to be 220kg became the 23rd bluefin satellite tagged in the 2008 project.

As often happened in 2008, the bite turned off at dawn and within a few hours Cerveza II turned for home. This leg of the project was quite eventful and challenging. But with 23 bluefin tagged, the bluefin team at Stanford, Blue Water Marine Research and Auckland University are quite happy with the achievements of 2008. Two satellite tags remain with Chinner who might have an opportunity to tag this week on his final charter of the season. Chinner has seen and done it all before and we’ll be grateful if he can put these last two out. But if not…well we wait with ‘baited’ breath for the data from these other 23.

We also heard from the crew of one of the commercial hoki trawlers that they could see several satellite tagged and conventionally tagged bluefin swimming under their boat, feeding on hoki scraps as the nets were hauled aboard. Great news to give us another shot of confidence that things are going well!

Monday, September 22, 2008

Birthday Bluefin – August 27, 2008

George Shillinger reports from New Zealand on a birthday outing with the Cerveza 2

Following four back-to back runs on three different vessels, I was craving some rest but anxious to finish the tagging work with our team in Greymouth. I had already extended my trip and could not afford to stay any longer.

Figure 1: The docks at Greymouth (Image: George Shillinger)


I was slated to present at the Biologging 3 Conference in Pacific Grove, CA on September 2, 2008 and had to return the US to prepare my talk.

Figure 2: Biologging 3 Conference Logo (Logo by Kate Spencer)


With good weather still on the horizon, Captain Larry announced that we would be making another quick turnaround in Greymouth. Unfortunately, time was too tight for a dinner reunion with the 4Gs. We had plans to depart the following morning with a group of anglers from Auckland who were eager to assist with the tagging effort. I hurried back to the hotel to organize my gear for tomorrow’s deployment.

Figure 3: Revington’s Hotel – our home base in Greymouth (Image: George Shillinger).


Figure 4: Tim Sippel (left) and George Shillinger (right) work in the “office” at Revington’s Hotel (Image: John Holdsworth).


Figure 5: The Jade Café in downtown Greymouth – a breakfast venue for the tagging team when we are not on the water (Image: George Shillinger).


Fortunately, I was able to make a quick morning visit to the dental office of Dr. Garry Rae. It was my birthday in New Zealand (August 27), and Dr. Rae had kindly promised to repair a crown that I lost while chewing candy on my first Cerveza 2 charter (see blog #1) of the tagging season. Thank you, Garry, for the excellent birthday gift!

Figure 6: George and Dr. Garry Rae at Dr. Rae’s dental practice in Greymouth.


Larry arrived at the docks with positive news from several boats about recent catches of large tuna in the Trench. Although weather reports advised otherwise, the winds had resumed and the weather appeared to be taking a turn for the worse as we headed out over the Bar.

Figure 7: View from the boat while crossing the bar (Image: George Shillinger).


The skies darkened and the winds increased to 20-25 kts as we raced towards the grounds. The sea had turned into a rollicking mass of whitecaps and spray, making for an exceptionally bumpy ride. A few of the passengers hunkered down to absorb the buffeting, laying prone on the cabin floor, while the crew focused on prepping tackle and bait, peeling spuds, and keeping cooking gear from launching across the cabin.

Figure 8: Vessels Cascade (left foreground) and Cova Rose (right foreground) wait with Cerveza 2 for the Vessel Rehua (left background) to pull its hoki bag (Image: George Shillinger).


The first trawler that we encountered upon arriving at the fishing grounds was the NZ trawler, Rehua. Sportfishing vessels, Cova Rova and Cascade joined us, rolling in the swells while we waited for Rehua to pull the bag.

Figure 9: Vessel Cascade in the trough (Image: George Shillinger)


With the bag ascending, Captain Larry positioned the Cerveza alongside the trawler, while Deckies Redz and Josh prepped a hoki bait. Angler Tom Thomson, anxiously manned the chair as the Auckland anglers prepared for battle.

Figure 10: Seals and birds feast on scraps from the hoki bag. (Image: George Shillinger)


Over the course of the next 15 hours, we battled strong winds (20-25 kts), a rising swell (to 3m), and three giant tuna. The bite never slackened, but sadly all three fish were lost (2 broke off at the trace and another when the line snapped) before any tags could be deployed.

We finally deployed our first tag of the trip when angler Tom Thomson succeeded in bringing an estimated 225 kg fish to the boat, after a 3+ hour battle that began in the pre-dawn at 3:55 a.m. Although we captured fleeting glimpses of the trace on several occasions throughout Tom’s fight, the fish repeatedly turned tail at the rail, disappearing into the darkness every time capture appeared imminent. Deckie Redz wired the fish and made good on his promise to present me with a “Birthday Bluefin.”

Figure 11: Sportfishing vessels gather around the NZ Vessel Amaltal Enterprise as she pulls in a loaded bag of hoki. (Image: George Shillinger)


Figure 12: After three lost fish and one tag deployed, Tom Thomson (left), George Shillinger (center) and Tom’s team of anglers take a bluefin home for dinner. (Image: Deckie Redz).


With the first tag of the trip finally deployed, the anglers collectively decided that it was time to take a fish. Three hours later we were on our way home with an estimated 230kg tuna headed for the icebox. Meanwhile, I took advantage of the opportunity to investigate the tuna’s gut contents (filled with hoki bones – no surprise!) and collect tissue and DNA samples.

Figure 13: Hoki bones in the stomach of a giant Pacific (Nothern) bluefin (Image: George Shillinger).


As we headed back towards Greymouth, the crew surprised me with a ice cream birthday cake --- apparently a Kiwi speciality (for kids) --- that generated congratulations and fond memories from all aboard!

Figure 14: Kiwi Style birthday – an ice cream cake from the crew of Cerveza 2 for George Shillinger! (Image: Josh Worthington)

Friday, September 19, 2008

Tagging with the trawlers in the Trench

Pete Saul reports on his back-to-back trip on Cova Rose chasing giant Pacific bluefin tuna off the west coast of New Zealand.

It was a quick turn-around with only a few hours ashore. The charter was three enthusiastic south Australians who wanted to land a fish only if it was a potential world record.

Figure 1: The Cova Rose preparing to depart from the Greymouth docks. (Image: George Shillinger)


With the crew all tired from an exhausting 48 trip in which the weather was testing at times and the fishing hard, it was fortunate that one of the deckies, Grant, was returning to Nelson, and Bryce from the first trip was rejoining the boat. He was able to navigate back out to the grounds while Tony, Norm and myself caught up on some rest.

The forecast lived up to its promise, with the sea calming down beautifully by the time we had found our first trawler, the NZ vessel Rehua, north of the Hokitika Trench. At ten past midnight, on just the second pass, we hooked up with Gavin Solly in the chair. This turned out to be an epic battle of five hours and we did not tag the fish which was brought on board. Gavin was astounded at the power of these fish in his first encounter. Even though we had the trace up after just twenty minutes, the fish simply would not give in. We fished near the Rehua until after dawn with only one further strike which did not hook up.

Figure 2: The Cova Rose as seen from the Cerveza 2; fishing off the bag of the NZ Vessel Rehua. (Image: George Shillinger)


Skipper Tony decided to move away and have a look at one of two Korean joint-venture vessels not far away. We have had absolutely no luck near these boats in the past, but this time the move turned out to be a master stroke. The boat had very promising marks on the sounder alongside it, and the fish proved willing to bite. We soon had our second angler, Troy Nissen, hooked up, and he succeeded in bringing his 260 kg giant to the boat in 90 minutes. A bait cast into the sea immediately after tagging Troy's fish was instantly seized by another tuna. The school had deserted the trawler to stay with their stricken mate, and we made the most of our good fortune. Our third angler, Ray Doody, a three year veteran of the fishery, brought his 230kg fish to the boat in 135 minutes as we drifted and chummed on the spot where Troy's fish was hooked. By late afternoon we had experienced several bites that had escaped the hook, but shortly afterwards hooked a tuna that was brought in by Troy in just 30 minutes.

The anglers were getting the hang of this quite rapidly. We hooked up again just 8 minutes after tagging Troy’s second tuna, with Ray again in the hot seat. This fish, another estimated at 220kg, was tagged in just 27 minutes. In an effort to speed things up we tried handlining some tuna, but after several misadventures the fish went off the bite.

Tony moved to another New Zealand Trawler, the Amaltal Enterprise, which was doing its last tow of a six week trip. We followed the trawler for a couple of hours while the anglers had a bit of a rest. Just before dawn the skipper radioed us to say that he was about to haul his net. The cooperation of the commercial vessels has been absolutely outstanding, with Tony’s long experience in the commercial fishery helping enormously as he knows all the skippers personally. At 0530 Gavin hooked a tuna which proved to be the last of this trip. At an estimated 280kg it was the biggest we encountered this time, but was brought alongside in just 25 minutes. A tough struggle on the trace ensued with the extremely green fish fighting all the way up. It took all three crew to bring the tuna within range of the tag pole for a good shot. Unfortunately while trying to maneuver the fish to the stern for a DNA sample it smashed the trace and headed for the depths at great speed.

Although scheduled to stay out for 48 hours, we headed home into a north-east wind and rain. The bait was all but gone, and the anglers all but exhausted after yet another successful West Coast adventure. After two successive trips, I was also due for a rest. For me it was time to head for home. With four tags left to deploy, Tim will replace me for some more trips with Captain “Chinner” and crew.

Thursday, September 18, 2008

Tagging Tuna in the Trench with the 4Gs

Latest New Zealand Tagging Report - Submitted by George Shillinger

Although it was difficult to leave my colleagues and the crew behind on the Cova Rose, it was exciting to board the Cerveza 2 again and to rejoin Captain Larry Johnston, his crew, and the Greymouth Guzzlers (4Gs).

Figure 1: Captain Larry Johnston (left) conducts pre—departure briefing with Mike Trousleau (center) and Dr. Gary Rae (right) in the cockpit of Cerveza 2. (Image: George Shillinger)


The 4Gs were back for their 2008 Cerveza 2 charter and had been eagerly awaiting the rare good weather window for another crack at the giant bluefin. In spite of conflicting reports, the weather cooperated and I joined the 4Gs for one of the smoother Bar crossings in recent memory. The winds had calmed to less than 10 kts and the swell had dropped to under 2m --- classic bluefin fishing conditions for the Trench.

Figure 2: Ocean fog and mist envelope the West Coast of the New Zealand’s South Island --- a northward glimpse from the mouth of the Greymouth River. (Image: George Shillinger)


Thus far, the fish had proven a bit more fickle than those of the past two seasons. During previous years, we experienced a steady twenty-four hour per day bite, due in large part, to the high number of hoki trawlers working the trench around the clock. This year, fewer trawlers and a full moon presented additional challenges. But, in general the “bite” was normal, kicking-off at dusk and waning shortly after dawn – a consistent pattern supported by our own analyses of tuna dive behavior, and familiar to many fishers worldwide.

Figure 3: Deckie Josh baits the line for angler Kevin Beems in preparation for the evening bite (Image: George Shillinger)


Sure enough, our first hook-up occurred at 7:00 p.m., on the cod end of a bursting hoki bag, as darkness cloaked the trench. The monster tuna was brought to the boat within less than an hour but it suddenly awakened at the trace, snapping the leader with a swipe of its jaw, and charging into the depths before we could muster a tag shot. Undaunted, we dashed back to the trawler and tossed another bait.

Figure 4: Deckie Redz prepares to toss a hoki bait behind the trawler Rehua (Image: George Shillinger).







A second fish, green and full of fury, was lost again at the trace before 8:00 p.m. Finally, shortly after midnight, following an epic 2.5 hour battle, angler Ian Boustridge (Beau) brought an estimated 350 kg giant to the rail. Deckies Adrian and Redz masterfully wired the monster tuna for me to make the tag stick, while deckie Josh Worthington extended over the rail, snagged a fin clip, and severed the trace at the eye of the hook. The leviathan fish glared menacingly upwards at us as the leader broke and then kicked away with a series of powerful tail beats.

Figure 5: George Shillinger prepares to deploy a satellite tag on a giant bluefin captured by Angler Ian Boustridge and leadered by deckies Adrian and Redz. (Image: Garry Rae)


The team continued to fish through the night and several hours later, during the pre-dawn, disaster struck as angler Clark Boustridge brought another beautiful fish (~ 260 kg) to the rail. The fish, still green, charged under the boat and was mortally wounded by the propeller. The loss of the fish that we were planning to tag was difficult for all. We collected fin clips and tissue samples for DNA and stable isotope analysis and the 4Gs took the remainder to share among family and friends.

A few hours later, at 8:30 a.m., Garry Rae landed the final giant bluefin of our trip. It was a thrill for all of us to “see the dentist in the chair” again at last!.

Figure 6: Angler Garry Rae in the chair on a dawn bite as deckie Adrian awaits the trace. (Image: George Shillinger)


During the course of a 1.5 hour fight, Garry skillfully brought the fish (~ 200+ kg) to the Cerveza 2, enabling deckies Adrian and Redz to guide the fish into position for an excellent tag shot.

Figure 7: George Shillinger prepares to tag the fish captured by angler Garry Rae with deckies Adrian (center) and Redz (left) working the trace. (Image: Ian Bosutridge)


Figure 8: Deckie Josh Worthington (holding cutter) prepares to cut the trace on angler Rae’s bluefin. (Image: George Shillinger).


Finally, after 48 exciting hours of battling and tagging fish in the Hokitiak Trench, the 4Gs and Captain Larry made the executive decision to return to Greymouth. We were all weary but grateful to have experienced yet another exciting and memorable adventure --- and we are all looking forward to seeing this year’s tag returns and hoping for another trip together during 2009!

Figure 9: Snow capped mountains and seabirds frame the scene during our return from tuna tagging off Greymouth, New Zealand.

Thursday, September 11, 2008

Second Week Tagging Giant Pacific Bluefin in New Zealand

Latest news from the New Zealand Pacific bluefin tagging team.

Submitted by John Holdsworth, Pete Saul, Tim Sippel, and George Shillinger


Hopes were high for a successful conclusion of the pop-up satellite tagging in the second week. To maximize our tag deployment efforts, George Shillinger (see his blogs #3 and 5) transferred to the Cerveza 2, leaving Pete, Tim, and John to continue with working with the Cova Rose. As both teams prepared to depart, the weather had cleared again allowing the boats to leave the port of Greymouth on schedule.

The depth sounder showed that the fish were around but tended to stay down during the relatively calm first day of this second trip on the Cova Rose. The fish appeared to be hovering beside the hoki trawlers at 30 to 40 m, too deep for our baits until the feeding frenzy started as the trawl net surfaced (usually once every 3 or 4 hours).

Figure 1. Bluefin marks at 30-40 meters depth.


The hoki fishery attracts all sorts of attention from hungry marine animals. From above, tens of thousands of seabirds, from dainty petrels to huge wandering albatross, competed for scraps and whole hoki. From below New Zealand fur seals dart in and out of the chaotic scene, competing for easy hoki meals with our primary target, giant bluefin.

Figure 2. Tens of thousands of seabirds compete for scraps as the trawlers haul their nets.


A bait thrown into the mêlée at the right time could result in a hook up in seconds. If the tuna were too slow it wasn’t long before diving birds or an agile seal would have our bait at the surface and the opportunity could be missed.

Figure 3. Deckie Norm tosses a hoki bait as the trawler “Rehua” approaches while pulling its nets.








The crew on Cova Rose also had a number of tuna strikes the first day which did not result in hookups. Professor John Montgomery from the University of Auckland was in the chair for the first solid hookup. The 130 lb rod bowed and line peeled from the reel in the giant’s first run. Suddenly the weight seemed to double and the 130 lb nylon top-shot parted and the fish was gone. Possibly another large tuna had swum through the line.

This is a 24 hour a day fishery. In fact catches can be better at night and early morning. An angler must be in the chair and ready all the time our bait was in the water. Volunteers Graham McGregor (Ministry of Fisheries), John Montgomery and Arthur Cozens (University of Auckland) spent long hours on a cold and windy aft deck waiting for that hook-up.

It wasn’t until just after midnight in the waning hours of the charter that researcher and angler Tim Sippel (Auckland University and Blue Water Marine Research) brought a fish in range of the tag pole. Determination to bring a fish to the boat for tagging meant this solid 200 kg fish was online for just 32 minutes, and proved a little uncooperative at the boat. With the tag in place, wireman Norm was leading the fish toward the fish door to get a valuable fin clip for DNA analysis when it turned and snapped the 500 lb trace close to the hook.

Skipper Tony Roach “Chinner” put us back into the thick of more hungry bluefin and it wasn’t long before we had another solid hookup. John Holdsworth (Blue Water Marine Research) was the angler this time. There are not many heavy tackle fisheries left around the globe, but this is certainly one of them. It took a while to get used to the weight of the fish with the reel on sunset (40 kg over the rod tip) for almost the entire time. This fish, estimated 270 kg, took 47 minutes to get to the boat, tag and release. It departed with a couple of tail flicks and a shower of spray. Just two giant bluefin were tagged that trip, and both came in the early hours of 28 August, not long before we returned to Greymouth.

Figure 4. John Holdsworth hooks up just before dawn to catch the second and final fish tagged of the charter.

Meanwhile, George Shillinger and the team on board Cerveza 2 were also finding the fishing challenging. He describes his ensuing adventures in Blogs # 3 and # 5, while Pete Saul and Tim Sippel respectively describe their subsequent trips onboard the Cova Rose and Cerveza 2 in Blogs #4 and #6.



Wednesday, September 3, 2008

TGF Co-Hosts International Biologging Conference


If it swims, flies, walks or climbs, researchers are likely presenting data on its habits and haunts this week at the Third International Biologging Science Symposium. The Tag-A-Giant Foundation and the Tagging of Pacific Predators program are co-hosting the 200+ person meeting at the Asilomar Conference Grounds in Pacific Grove, California.

“Biologging” is the use of electronic sensors, implanted or attached to animals, to track and record their movements, behaviors, physical setting and physiological state in the wild - exactly what TGF does in its electronic tagging research.

Over 130 pioneering researchers from 20 different nations are presenting the most recent findings in this rapidly developing discipline. Symposium sessions focus on advancement of biologging technology, animal behavior, monitoring physiology, climate change, habitat preferences and utilization, and new multi-species observatory networks that take a snapshot of the entire ecosystem. There will also be a special session focused on how biologing data is being applied to conservation and management of wildlife and ecosystems to protect the ocean’s most endangered inhabitants.

The bulk of the presentations will focus on marine life – ranging from whales to penguins to sea otters to swordfish, but studies on a few land animals such as cougars and koalas will be included. Presentations on bluefin tuna include research on all three species - Atlantic, Pacific, and Southern. Several studies partially funded by TGF will be presented: a habitat utilization model for Atlantic bluefin tuna on their Gulf of Mexico spawning grounds, using genetic techniques to differentiate between western and eastern Atlantic bluefin tuna, incorporating tagging data to improve Atlantic bluefin tuna stock assessment models, and habitat preferences of migrating Pacific bluefin tuna.

Other biologging studies that will be highlighted research whether sonar plays a role in mass beachings of beaked whales, or whether captive-bred sea turtles and farmed fish are able to survive in the ocean to the same degree as their counterparts raised in the wild. Another study utilizes tiny accelerometers attached to the jaws of predators to calculate their food intake by measuring the opening and closing of their jaws. Still another uses a 3D version of an accelerometer to record postures and movements of nurse shark courtship and mating.

To read more about the Symposium, including the program and presentation abstracts, please visit http://biologging.wordpress.com/.

Monday, August 25, 2008

NEW ZEALAND GIANT PACIFIC BLUEFIN TUNA TAGGING UNDERWAY!

This just in from TAG scientist and Stanford Ph.D. student George Shillinger, who's in New Zealand tagging giant Pacific bluefin tuna...

The 2008 New Zealand Pacific bluefin satellite tagging effort is underway. I reunited with Pete Saul and colleagues, John Holdsworth (Bluewater Marine Research) and Tim Sippel (Auckland University) in Greymouth on August 16, 2008 for another shot at tagging the giant tuna off the West Coast of New Zealand’s South Island.

Figure 1. Greymouth, New Zealand, August 16, 2008: A view from the Cova Rose (Image: George Shillinger)




As always, weather is a limiting factor in our New Zealand tuna tagging efforts. August is a harsh month in the Roaring Forties, and the South Tasman Sea presents a challenging work environment for fishers and scientists alike. The Bluefin sportfishery here is opportunistic and good weather is never taken for granted. We were fortunate to arrive in concert with a ridge of high pressure, and seized the opportunity to begin our deployment efforts.

We joined Captain Tony Roach (Chinner) and his deckies, Norm and Bryce (Big Boy) on the vessel Cova Rose for our tagging expedition.

Figure 2. Angler Mark Hemmingway awaits as deckies Bryce and Norm bait bluefin.
(Image: George Shillinger)


Over the course of the next 48 hours, we fished alongside two trawlers from the Hoki fleet and tagged seven fish, ranging from an estimated 200-350 kg (~350-620 lbs). We were aided in our efforts by a group of game fishing enthusiasts from the New Zealand Big Gamefishing Council, including Mark Hemmingway (one at ~240 kg and another at ~ 250 kg), Vance Fulton (~320 kg), Clyde Frazier (~200 kg), and Dave Wallace (~ 350 kg), I was granted a rare opportunity to battle a giant and brought a estimated 250 kg fish to the leader in 62 minutes, which was tagged by Tim Sippel.

Figure 3. Hoki trawler which attracts bluefin. (Image: George Shillinger)





Figure 4. A hefty bluefin being tagged just before being released.
(Image: George Shillinger)



The deckies, Norm and Bryce, handlined another giant tuna with an estimated weight of 280 kg in a span of fifteen minutes! Handlining has proven to be an effective technique for getting the fish to the boat quickly but the tradeoff is that the fish are livelier (greener) and more difficult to handle – thus making it difficult to position the fish for tagging and DNA collection.

Figure 5. Deckie Norm reaching out to sample DNA with a small fin clip.
(Image: George Shillinger)


Towards the end of our Cova Rose charter, Captain Larry Johnston, of the Cerveza 2, invited me to transfer to his boat to join a 48 hour charter. The anglers on the boat were familiar with our research efforts, having previously invited Pete Saul to join them during 2007. Captain Larry put us on fish and angler Denis Lucardie captured a fish weighing an estimated 310 kg and Frank Foster caught another weighing an estimated 280 kg. Deckies, Adrian and Redz brought the fish to leader, adding another two fish to our tagging tally.

As dusk approached on the second day of the Cerveza charter, I was granted an opportunity to join another charter on the vessel, Oracle, captained by Mike Boswell, and crewed by Bevan Johnson (Beefy). The crew and anglers on the Oracle were enthusiastic about the opportunity to support our research efforts. Andrew Clavroueh (~ and Aaron Hunter pulled in two fish respectively weighing an estimated 240 and 260 kg. The Oracle fishing approach involves stand-up gear, where the angler has to support the full weight of rod and fish without the aid of a gamefish chair.

Figure 6. Angler Aaron Clavroueh battling a bluefin on stand-up gear.
(Image: George Shillinger)



Figure 7. Tuna tagger turned tuna angler, George Shillinger.
(Image: George Shillinger)


Forty eight hours later, we wrapped up the Oracle charter and headed to the landings at Westport, approximately 90 km north of Greymouth. At the docks, I collected another five samples of DNA and muscle tissue from fish that had been landed by other crews. The Westport fishery represents one of two recreational fishing ports on New Zealand’s South Island West Coast – the other being Greymouth.

We are excited by the reception that we have received in Greymouth and Westport, and the support and genuine interest that we have encountered from the fishing fleets. Tomorrow, the team from Bluewater Marine and Auckland University will be heading to Westport to discuss management of the NZ bluefin recreational fishery and to provide feedback on the results of previous tagging efforts with fishery stakeholders (captains and crews). I will be heading offshore on the Cerveza 2 with the Greymouth Gourmet Guzzlers and high hopes for a repeat of our successful tagging efforts during 2007.

Figure 8. “Greymouth Guzzlers” accompanied by George Shillinger before departing for their next tagging adventure on 25 August 2008.