Friday, July 31, 2015

Bluefin Satellite Tag Hunt

Low Fog kisses the Highlands along the Cabot Trail
Place yourself for a moment in the office of a tuna tagging scientist staring at a map with a GPS location of a popped-off mini-PAT satellite tag.  The tag had been attached to a Giant Bluefin Tuna for the past 10 months, and it contains a virtual diary of its movements, behaviours and environments encountered.  The tag is sending a summary of the tuna’s story to a satellite which relays it to your computer.  This summary data is like reading the first and final chapter of a novel and the story line on the back cover.  It’s valuable and you get the highlights and main point of it all, but you feel cheated somehow, especially after you spent weeks travelling and fishing to tag the tuna in the first place. If you can get the tag back, you can download the entire "story".

A lot of tags pop off far from shore, well beyond reach of an inshore vessel’s range.  So what happens when a tag comes to the surface 15 kms from shore?  And 25 kms from the nearest port where you know a local fisher who has a boat at the dock?  You scramble; you email, call and coordinate a recovery as fast as humanly possible…and then you pray, for good weather, calm seas and good visibility.  On Wednesday, this week, such an event happened.  Although I wasn’t the scientist staring at the map of the first GPS location, early Thursday morning...I was the scientist along with a Honours student from Acadia University rushing to the dock to jump on board the ‘Mary Heather’ captained by TAG-A-GIANT’s Captain Lloyd MacInnes based out of Little River, Cape Breton, Nova Scotia.
The search for the tag begins
Finding a tag the size of an egg with a thin black antenna sticking out would be an ok Easter-egg-hunt on land. However, throw in waves, a large area, a GPS location that is hours old, and the fact that the tag is floating with only the antenna peaking out, all of a sudden the easter egg hunt isn't quite as easy. That’s where Seth Newall, a Honours student from Acadia University comes in.  He brought a "tag locator" with him, which picks up the specific frequency of the tag and allows us to home in on the signal.  It’s a lot like playing ‘hot-cold’ as a kid, except you’re still looking for a black, half-submerged tag within 300 to 50 m of the boat.  So with Captain Lloyd at the helm spinning circles and squiggles on his chart display, Seth relaying signal strength of the tag, and myself standing on the cabin roof searching the water, we played that very game.  It was bit foggy, but relatively calm, no breaking waves or chop.  With help texts coming from TAG-A-GIANT’s Robbie Schallert in Texas, we honed our rookie skills using the tag locator.  Seth’s signal strength got stronger as the search continued.  After 3 hours of playing hide-and-seek, I spotted the black egg with antenna sticking straight up, 20 m off the port bow.
“I got it!” I yelled out, “10 o’clock! 60 feet off the port side!”
“I see it!” confirmed Captain Lloyd.
“Seth, grab the dip net while I keep an eye on it!” I instructed.
Captain Lloyd had the boat alongside the tag within seconds.  He wasn’t waiting for a dip net.  He had a deck-brush in hand and was frantically sweeping the tag closer to the boat.  Seth netted our find and with that, we had in hand the day-to-day story of one Bluefin.
Relieved Capt. with the tag

Close up of the Wildlife Computers miniPAT
Steaming back to port, the sun broke through the fog to illuminate the sea’s surface and rocky cliffs onshore, yet the lush green mountain tops of Cape Breton’s Highlands remained covered.  A pod of white-sided dolphins broke the surface and a puffin dove under upon the Mary Heather’s approach.  Some gifts in view while others remained out of sight, a fitting summary to our search’s conclusion.
Acadia Team with the tag safely secured!!
-          Written by Aaron Spares, Acadia University Coastal Ecology Lab 

Tuesday, March 17, 2015

Chagos 3.0

The team from Stanford University and The University of Western Australia are back for a return trip to the British Indian Ocean Territory (BIOT) to service (rebattery, download data, replace moorings and add new receivers) the acoustic array, as well as tag sharks with various electronic tags...CATS camera tags, Wildlife Computer miniPATs and SPOT tags, Lotek pop-ups, and Vemco acoustic tags.
Dr. Aaron Carlisle tapes up a
Vemco acoustic receiver

Dr. Jon Dale gets the shark line ready

Saturday, October 25, 2014

The Coal Mines

Fishing has moved a little North but it hasn't slowed down...the tag team tagged six fish on eight bites. The fish are ranging from 400 to 800 lbs and we are putting on a variety of different electronic tags.

Friday, October 24, 2014

The Carrie Anne Show

We only had a half day but by the time we were back to the dock...five fish had electronic tags...and the F/V Carrie Anne passed off four of them. Captain Steve MacInnis started the day off with three fish in a row...he would pass us a fish and by the time we finished fighting and tagging the bluefin...he was hooked up again.

Captain Steve MacInnis passes off another bluefin

Not to be out done...the F/V Nicole Brandy passed us two fish in a row...the tagged fish was a beautiful 800 pounder.

Bluefin getting spun around before going out the door

Before we could set up to fish ourselves...the Carrie Anne had a double hook up. One of the fish got a tag and the other pulled the hook...but the excitement continued aboard the Carrie Anne as another bluefin tuna bit the hook right as the next bait hit the water.

Tag team takes a selfie while Lloyd reels in another fish

Monday, October 20, 2014

Four more on the board

We had another great day on the water...we met the F/V Carrie Anne and F/V Nicole Brandy from Arisaig right off Port Hood early Sunday morning. Before we even had our bait, Captain Steve MacInnis aboard the Carrie Anne was hooked up. The fish was tagged and released and our busy day on the water continued with two consecutive fish from Captain Bernie Chisholm on the Nicole Brandy. We finally got our hooks in the water after lunch...and once again, while the sun was setting we hooked into a nice 700 lber.

We didn't make it out today, but we are hoping to get back on the water tomorrow and Wednesday.

Dr. Steve Wilson release a bluefin tuna with the Bay Queen IV crew
Captain Bernie and his son Kenny prepare to pass us a fish
Waiting for the bite

Saturday, October 18, 2014

Canada 2014

The 2014 Canadian tagging season has begun with two fish tagged and released. We had a beautiful day on the water and we will be at it again tomorrow.

Llyod McInnis fishing a bluefin
Sunset while heading back to the dock in Port Hood.

Friday, August 1, 2014

Morocco Trap Tagging

Divers pick out individual fish to be tagged from the holding pen at the end of the trap system.
Divers guide a bluefin tuna into the supersized sling.
A bluefin tuna is lifted out of the holding pen by crane.
The bluefin being measured.
Scientist Noureddine Abid from INRH puts a piece of bluefin DNA into a vial.
TAG Scientists Robbie Schallert, Pablo Cermeno, and Barbara Block. traveled to Morocco in May to work with scientists from the Moroccan National Institute of Fisheries Research (INRH) and the tuna trap "Es-Sahel" (Larache, Morocco), owned by Société Maromadraba. The objective was to gain more insight into the migratory patterns of large bluefin tuna in the North Atlantic. These particular fish arrive annually in the Spring on their way to spawn inside the Mediterranean. And the traps, as described by Dr. George Shillinger (Moroccan Traps), catch some of the bluefin on their journey...this provides scientists with a fantastic opportunity to tag and release many "giants" quickly and easily. This is the third year our TAG team has been to the traps as part of our our collaborative work with ICCAT and WWF to place Wildlife Computers' mini-PAT tags on the 300-500 lb fish.

Dr. Block carefully inserts a satellite tag before the fish is released outside of the trap.