Wednesday, July 6, 2016

Top of the Tagging Pacific Bluefin Tuna Learning Curve!

Barb and Robbie tagging a Pacific bluefin
The trip aboard the shogun reached new territory today as the team aboard hit historic high levels of excitement as we finally had the banner day we were working towards. Five times today we had explosive bites while Kite fishing on breezing schools of the largest Pacific  bluefin we have ever seen in the eastern Pacific. Captain Aaron and Angler Chalie Morito along with crew member Tyler and several others worked seamlessly as a team sighting school after school of large almost giant bluefin feeding at the surface. After hookup long fights pursued in heavy tackle culminating at the swim step where the Tag team took over and gracefully captured each fish in slings barely large enough to hold the fish. Four men lifted the fish to four on deck tackling over 300 lbs of lift. The TAG team handled the fish like in a pit stop- each fish came came into the tagging station and were double tagged then sent on their way. Fish were feeding on Red crabs and anchovy. The fish had DNA and RNA samples taken and swam away strong. Five fish over six hours were  tagged and he team felt a sense of accomplishment as the techniques worked out early in the week succeeded with enormous efficiency and success. By the end of the day all ten satellite tags aboard were out in the sea on the largest Pacific bluefin the team has ever tagged in the North Pacific.  This is terrific for our efforts to learn the exact timing of when the fish spawn. 

 -Barb

A large bluefin being double-tagged on the Shogun  deck


Tuesday, July 5, 2016

Archival Tagging Bluefin in Mexico!

The focus turned from tagging large bluefin with satellite tags
in  US waters to getting out surgically implanted archival tags in
high numbers today- and to help us achieve our mission- our Mexican
colleagues at Baja Aquafarms  of Ensenada, Mexico- contributed 32
fish ranging from 40 to 70  lb fish for tagging. We came to some tow
pens maintained by the famr early in the AM, that had beautiful f2016
captured fish circling-that had been caught about a month earlier.
The fish were already feeding and looked quite well. To catch the
fish we used lift poles- manned by two of the crew, and with the help
of their divers and some members of our team- we coordinated the
capture of the fish in a sling, the removal of the hook, and the
transfer to the archival tagging station. The entire operation took
less then two hours (30 fish tagged), and was orchestrated from start
to finish with well coordinated steps. Fish were caught on a barbless
hook by Charlie, Aaron and Renne, then moved to a sling manned by Dr.
Daniel Madigan. Dan managed to keep the fish in the sling with some
water along with two divers assisting and passed off the fish to
teammates waiting on deck led by Dr. Luke Garnder. Luke's team
managed to bring the fish to the tagging station and were greeted by
Drs. Dale and Block, and TAG scientist, Mr. Robbie Schallert.
Together this team placed a surgical archival tag in the fish, took a
sample of muscle for mRNA, and DNA samples, and completed the process
in quick succession 30 different times! All fish looked good and what
made the entire team happy- is that just as we pulled away from the
pens- the captain sited more wild fish- and we within the space of an
hour tagged a few more of the same size class in the pen. It was a
glorious moment- to get about 32 tags out- and all on 3-4 year old
fish. These tags will last up to six years in the wild taking high
resolution data. And have the promise of showing how these fish
mature- the ontogenetics of their changing behavior and the route to
the various spawning grounds. Their only fault is that we need to get
the tags back!

-Barb

Monday, July 4, 2016

The Pacific Bluefin Got Even Bigger!

On Independence Day 2016 the Tag team aboard the Shogun actually made some real history. We have struggled to learn how to capture tag and release the largest Pacific bluefin tuna we have seen in our lifetime and this day proved more successful then the previous two. Today aboard the shogun, a long range recreational fishing boat out of San Diego we were able to catch three Pacific bluefin that taped  twice on two fish to 184 cm (72-73 inch fish) above the 200 lb class of Pacific bluefin and get them to the swim step. Two of the three  fish were in excellent condition for double tagging with pop up satellite archival tags and an implantable archival tag went in surgically in both. The tasks were challenging for the team from the hook up on a kite with a surface bait to the fight on heavy stand up tackle in the open ocean.The coordination and capacity for our team to capture in a sling and lift a large fish and the water draining from the  sling to the deck for tagging. Led by Robbie Schallert of TAG and Dr  Luke Gardner of Stanford the men with help from many others were able to place the large fish in a sling and move it to the deck placed Mats for tagging.   Pacific bluefin older the six years of age hold a secret we want to know: Where and when do they breed in the Pacific. The excitement aboard the Shogun is that this is a challenging operation and we are succeeding and improving daily. Five of these large fish have been hooked  successfully and three to date tagged and one sampled intensively. These fish hold a secret to he life history of bluefin we all seek to understand. This tagging trip working out the techniques to handle large bluefin for this realm reminds me of our work over twenty years ago off North Carolina in 1996 when a small team from the TRCC went out with Captain Bob Eakes to figure out how to tag and release this similar class of fish on the east coast. From the 1996 work we went on to tag 1300 Atlantic bluefin most bigger then the fish we are working on today. Our goal as we go forward is to satellite tag the larger bluefin we can catch in the Pacific but it's very hard to access these large fish. 

But confidence grows from catching three and releasing two large Pacific bluefin on the fourth of July and we are all excited about what we are seeing. The fish are packed full of red tuna crabs and anchovy. More bait and whales and Albatross and shearwaters making a hot spot on tthis region of our blue Serengeti of the California Current. 


Barb

Friday, July 1, 2016

Bluefin Tuna Special

Our Pacific bluefin tuna tagging and collecting trip  is out in the Pacific aboard the Shogun a recreational long Range fishing boat we've used annually to do this trip. The objective of the cruise is to electronic tag Pacific bluefin tuna and study their migrations to the spawning grounds in the western Pacific. In addition we hope to collect 15 to 20!bluefin tuna for the TRCC lab to conduct feeding studies.   For tagging we use two types of electronic tags each with their target size of fish and story we hope to tell with the data  One type of electronic tag is a Pop up satellite tag that is programmed to stay on the fish for one year and potentially show us where the largest year classes go after foraging in the eastern Pacific hot spots. This is a hot question in current Pacific bluefin tuna science. The other type of tag is called an archival tag. These tags are programmed to last six years and will provide in depth data in what a bluefin does over the entire period In 10-20 second intervals. That would be immense data and to far we've successfully used these techniques up to three years in the Pacific and five years in the Atlantic. These tags are brand new and when we put them in fish off the shores of North America we hope to see them five to six years from now recaptured. They have the potential to record the daily position, thus the journeys and behavior in high resolution for the entire six years.  They carry three languages  and all say Return for Big reward.bit takes a fisher person to get the tag back. But we know this works to date we have 53 percent returned in the Pacific and about twenty percent in the Atlantic.  It takes a lot of international cooperation but we are hopeful as this type of tagging has given Atlantic and Pacific bluefin tuna researchers the most  detail required to increase our knowledge of when and where tuna spawn a critical question essential to life history and management questions. In addition these tags provide oceanography and behavioral data essential for better understanding the fish. 

Slow Bite but Big Fish😎

Today the first of July l, we got off to great start with the pop up satellite tagging of our first fish which by measurement is the largest fish we ever have tagged on the Shogun. The bluefin tuna was caught by a crew member and measured 177  cm in curved length. We estimate the fish was close to 190-200 lbs. 


We caught the fish using innovative techniques by the Shogun crew and met the challenge of lifting it on board from a swim step and satellite tagging the fish.   If the tag stays on (a problem for these fast moving fish) we hope to get a year of data on where the bluefin tuna go to spawn.  Fish of this size class are very hard to catch as bluefin tuna vision is extraordinary. We were able to catch two more bluefin tuna of a smaller size class well above the size we intend to collect and for our first day we ended with two archival tags and the largest fish ever in twenty years of TRCC tagging. Great start! 

- Barbara Block

Monday, November 2, 2015

A 20-Step Guide to Tagging Giant Atlantic bluefin

There’s a long list of things that have to go right to tag a giant bluefin tuna.  Here’s an abbreviated version.

To tag a giant bluefin tuna you have to:
1.) Obtain research permits, program and prepare the electronic tags, and pack a lot of gear (don't forget anything!!!).

2.) Travel to a remote corner of Nova Scotia.

Autumn colors on Cape Breton Island, Nova Scotia. photo: E. Estess
3.) Wait, and wait, and wait for the weather to clear up. We were only able to fish 7 days out of 3 weeks this October due to weather!

4.)  Make sure your tagging boat motor is working.

5.) Find and catch large mackerel for bait.

6.) Search for a school of bluefin tuna (this can take hours/days).

Diving gannets and busting bluefin. photo: E. Estess
7.) Get a bluefin to bite the bait. Bluefin are notoriously picky about what they will bite. Last week we had a school of giant bluefin jumping through our mackerel baits without a single hookup!

A bluefin nails the bait! photo: E. Estess
8.)  Make sure the circle hook sets in the corner of the tuna’s mouth.

9.) Fight the fish to the stern without pulling so hard that you break the straining monofilament or bend the small metal hook.

Lloyd MacInnes and Dennis Cameron work together to angle in a
large bluefin for the tagging team. photo: E. Estess
10.) Guide the head of the tuna to the back door of the tagging boat. This is one of the hardest steps as the tuna can easily shake its head and pull the hook, particularly when the seas are rough.

11.) Use 5 people to pull the (up to 1,600lb) animal through the back door of the tagging boat onto a padded surgical mat.

12.) Place a hose into the tuna’s mouth to irrigate the gills with oxygen rich seawater and place fabric over the animal’s eye to reduce stress.

An eye cover and irrigation hose help keep the bluefin calm
and safe on deck.  Photo: R. Schallert
13.)  Remove the hook from the corner of the mouth.

14.)  Measure the length of the fish. This length measurement can be converted to an estimate of the fish’s weight at a later time.

15.)  Insert sterilized titanium darts into precise locations along the tuna’s back to anchor acoustic and satellite tags securely to the fish.  If done correctly, the acoustic tags will last for up to 5 years and the satellite tags will automatically detach from the animal after 1 year. Note: All tagging and handling procedures are conducted under the strictest animal care protocols.

Dr. Steve Wilson places a satellite tag into the dorsal muscle of a
large Atlantic bluefin. Photo: E. Estess
16.)  Insert a conventional/spaghetti tag with the phone numbers to call in case the fish is recaptured by a commercial fisherman.

17.)  Take a small (pencil eraser-sized) clip of the tuna’s fin to use for DNA sequencing.  This will allow us to understand if the animal is from the eastern or western Atlantic population of bluefin.

18.)  Lift and rotate the surgical mat to point the tuna’s head out the door (easier said than done!).

The Tag-A-Giant team lifts a giant bluefin to release it back into
the Gulf of St. Lawrence. Photo: R. Schallert
19.)  Guide the tuna out the door and watch it kick away into the deep blue of the Gulf of St. Lawrence.

20.)  Exchange high 5’s with the team!

The weeks of preparation and decades of expertise between the fishermen and researchers paid off and we were able to tag and release two giant bluefin on this trip. Our past results have shown that a majority of these tunas swim south from the foraging grounds in Nova Scotia to the Gulf of Mexico to spawn, and a small percentage swim across the Atlantic into the Mediterranean Sea for lesser-known reasons.  Only through long-term tagging studies like this will we be able to understand tuna migration and life history in order to effectively model population sizes for stock assessment and sustainable management of this species. 

Follow this link to the recent publication of our 8-years of tagging effort in Nova Scotia:
http://www.tunaresearch.org/reprints/Wilson_et_al_2015.pdf



Saturday, October 17, 2015

Tag-A-Giant Nova Scotia 2015: First Bite

It’s 6am and the floodlights cast their rays on the back deck of the f/v Bay Queen IV in Murphy’s Pond, Port Hood’s small commercial fishing port on the west coast of Cape Breton Island, Nova Scotia.  Captain Dennis Cameron and mate Lloyd MacInnes move around the deck coiling lines and crimping monofilament, bantering over the low rumble of the inboard.

Murphy's Pond in Port Hood, Nova Scotia
photo credit: R. Schallert
We approach the dock in our minivan loaded with crates of scientific gear and snacks for our day on the water. Dr. Steve Wilson and Robbie Schallert of Stanford University and the Tag-A-Giant Foundation lift a heavy silver crate and shuffle towards the Bay Queen IV, greeting the crews of the various vessels staging their gear in the grey light.  The crate is full of acoustic and satellite tags that, with luck, will be deployed on some of the largest tunas in the world.

The TAG team has been coming up to Nova Scotia every fall for the past 8 years and it shows.  Robbie cracks jokes with Melvin, Troy, Carl and more as we make our way down the floating dock. TAG has fostered lifelong relationships within the Port Hood community to create a collaborative environment; we couldn’t tag without their ocean expertise, and our research contributes to the sustainable management of their local bluefin fishery.
Loading the bait well with mackerel in the morning light
photo credit: E. Estess
 
We shove off as the clouds turn a light pink hue. The first order of business, as with all fishing, is bait.  Dennis eyes the echo sounder and quickly shifts out of gear when he spots a school of mackerel.  We keep the biggest mackerel in the live-well and motor off towards the tuna grounds.  Once we’re in the zone Lloyd rigs up two of the thick rods with live mackerel and pink balloons as surface floats, and the third rod is connected to a kite line to dangle a live mackerel at the surface.  And now we wait.

Radio calls come in from across the Gulf of St. Lawrence.  “Congratulations Bill, glad to hear you got your fish.”  “We’re marking lots of fish over here boys.”  Again, I take note of the friendly, collaborative nature of the fishery. Canadians really are as nice as people say!  After hours of silence we decide to pick up our lines and try another spot. More silence and no tuna marks on the echo sounder.

Searching the Gulf of St. Lawrence for giant bluefin
photo credit: R. Schallert
This is our second day on the water and the fishing has been silent.  Not to mention the weather has been on the rough side of the spectrum.  Part of me accepts that this is the nature of fishing- the bite is always hotter the week before. It’s fishing, not catching. Am I wearing my lucky tuna belt? I didn’t even bring any bananas on board.  These old catchphrases and superstitions drift through my mind as the hours flow on.

Deep down I know I’m paying a karmic penance after my last trip up to Port Hood in 2013, when we tagged up to 9 giant bluefin in a day and fished for 5 days straight in sunny, flat calm conditions.  I knew I was going to have to pay some dues, and bouncing around in the cabin with my hands shoved deep into my foul weather jacket to keep warm in the Arctic breeze, I accepted my fate with a meditative mantra, “It’s fishing, not tagging.”

Wind on the water. Waiting for action.
photo credit: E. Estess
At that moment, I watched the monofilament pull tight and the pink balloon float disappear. SNAP! The rubber band holding the Teflon leader guard broke and it rocketed down the line to protect the mono leader from the glass-sharp teeth of the giant tuna below.  BZZZZZZZZZZZ the line screamed off the reel as Lloyd rocketed across the deck and started cranking away.  Dennis began maneuvering the vessel, backing down on the fish to gain slack in the 300lb test line like a boxer circling their opponent in the ring.  The rod bent with strain as the fish made a run and Lloyd waited patiently for his chance to gain line.
  
But as quickly as it had come, the tuna jerked the hook from its mouth and was gone.  Lloyd silently reeled in the slack line, pausing to look at the bent hook.  Strike one, but after days of no action the reminder of the power of these animals was enough inspiration.  The fish are around. They’re always on the move throughout the gulf waters as they hunt for herring and mackerel, and it takes skill and decent dose of luck to line up on them.  Weather permitting, we will be putting in our time these next weeks to tag and release these beautiful giants, unlocking the secrets of their life history and migratory routes to inform the sustainable management of the tuna fishery.

Hoping for an evening bite.
photo credit: E. Estess