and parents succeed in a scientific treasure hunt
a storm, and school children came together on the morning of
Valentine’s Day to rescue a special electronic tag from the
flotsam and jetsam on a Frisco beach. It was a tag that popped
off a bluefin tuna and that contained valuable information about the
travels and habits of the big migratory fish.
- Here’s the way it happened.
On Wednesday night, Feb. 13, Dr. Molly Lutcavage, director of the Large
Pelagics Research Lab at the University of New Hampshire, e-mailed some
local boat captains, asking them to help recover a small, black pop-up
satellite tag that had apparently come off a bluefin tuna.
“The tag came off the fish a day or so ago,” her e-mail
said, “and it looks like it got blown onshore. It may be on
the beach by now unless the tide or wind takes it out again.”
- The juvenile, 48-inch bluefin was tagged in a special project last August off Cape Cod.
The Large Pelagic Research Lab initiated its Tag a Tiny program in the
summer of 2005. The goal is to study the annual migration paths and
habits of juvenile bluefin tuna in order to better understand and
conserve this highly sought after gigantic tuna whose populations are
threatened by overfishing.
A total of 98 juvenile fish were implanted with archival tags in 2005,
and another 25 tags were implanted in 2006 – all off the
coast of Cape Cod or Virginia. Last summer,
the scientists began attaching a new archival tag, the
X-tag. It is smaller than the standard tag with some extra
According to Lutcavage, the tag is manufactured by Microwave Telemetry,
Inc., of Columbia, Md.
“We deployed 32 X-tags on juvenile bluefin in
2007,” Lutcavage said in an e-mail, “and eight more
on giant bluefin (in Canadian waters). They're programmed to report
after 12 months. Sometimes the tags release early from the fish, and
they are programmed to transmit their data if they do. This was an
early release. We’ve had three reports in the past few weeks
-- two near Cape Hatteras and one northeast of Bermuda.”
And now one of the $4,000 tags was off the fish and floating toward land. The messages being received
from the satellite tag indicated that it was bobbing around in the
rough seas off Hatteras Island. All day Wednesday, heavy
winds had whipped up large waves and high tides along the island.
On Thursday, Feb. 14, the morning after Lutcavage sent her e-mail to
local captains, Nuno Fragaso of the Large Pelagics Research Lab,
contacted Tracy Shisler, a science teacher at the Cape Hatteras
Secondary School of Coastal Studies, and asked her for help.
He asked if parents of the students might go the beach, to the area from which the tag was transmitting a radio
and search for the tag before it got
washed out again in the tide. If the tag wasn’t found by the
end of the school day, he asked if students might join the search.
Lutcavage could see, using Google Earth, that the tag seemed to be
located on the beach, near the airport.
“We get data via satellite for about 30 days,”
Fragaso said in an e-mail to Shisler, “then our migration path modelers
do their magic and we get a track. Because of transmission schedules, we
don't get 100 percent data recovery. Having the tag allows us to get
100 percent recovery, which is why we are so eager to get it
Recovering the tag would guarantee not
only 100 percent recovery of the data, but the costly tag can also be
refurbished and implanted on another juvenile bluefin this summer.
Fragaso e-mailed Shisler a picture of the tag, Google maps, and GPS
coordinates for the location of the tag on Thursday morning. He also
noted that there was a $250 reward for the return of the tag.
The students got on the phone with their parents, and Shisler sent the
information to all of them with e-mail accounts.
Ashley Hodges, 13, a seventh grader in
Shisler’s class was one of the students who called her
parents. She reached her mother, Alex, who was on her way
from Buxton to Hatteras after having delivered another child to school.
The GPS coordinates put the tag on the beach very near Ramp 49 in
Frisco. Alex Hodges has a GPS unit in her vehicle, so she
turned off the highway and headed to the beach. She’s a
parent who is supportive of the school and its new coastal studies
mission, and she picked up on her daughter’s excitement about
the hunt for the tag.
Hodges says she drove the beach for almost a half hour and saw
nothing. She was ready to leave when she thought about
getting out and walking a while on the sunny but cool morning. In just
a few minutes, she noticed the debris line up near the dunes from the
storm’s high tides. She walked up and started
And there it was – the elusive satellite tag.
Hodges took it to school for Ashley and her classmates to see.
“The students were very excited about the parent finding the
tag,” says Tracy Shisler. “Alex Hodges brought the
tag in and the kids were thrilled to be able to see what the tag looked
like. I was e-mailing back and forth with Nuno, and I would read them
the emails. They thought of it as an adventure unfolding before their
Alex and Ashley had their picture taken with the tag, a photo that is
now posted on the Large Pelagic Research Lab Web site. Alex
and her husband, Dr. Al Hodges, donated the $250 reward for the tag to
the school for a trip the middle school students plan to the
Smithsonian Institution in Washington, D.C. Other parents,
Dan and Jennifer Johnson, arranged for special FedEx packing to send
the tag back to Microwave Telemetry in Maryland, the company that makes
the tags and will recover the data.
In another interesting twist to the great tuna-tag hunt, the inventor
and head of Microwave Telemetry, Inc., is Dr. Paul Howey, who has a
vacation home in Hatteras village and knows Tracy Shisler and her
“The process of recovering this tag has been a great
interactive learning opportunity for the Large Pelagics lab and the
Hatteras students and their parents, Molly Lutcavage wrote in an
e-mail. “The tag finders now know more about their local
marine resources and have had a first hand look at the very latest
technologies that fisheries scientists use to track marine
The students in Shisler’s sixth- and seventh-grade are
involved in a fish and oyster hatchery program. Shisler says they are
raising black sea bass, which will be tagged and released this spring.
They are getting ready to stip spawn oysters to help with the oyster
reef restoration project.
“A major theme of my teaching,” Shisler says,
“is that we need to be better stewards of our planet Earth. I
am hoping that they realize that whenever they get the opportunity to
help care for the Earth, they should step forward and help. I also want
them to realize that science is exciting, fun, and
ABOUT X-TAGS AND THE RESEARCH PROGRAM
From Dr. Molly Lutcavage, director of the Large Pelagics Research
Center at the University of New Hampshire:
The X-tags record depth and temperature every 15 minutes and light
levels more frequently. We attach them to the fish via a nylon dart and
a monofilament tether. At the programmed time, the nose cone of the tag
releases from the tether, the tag pops up to the surface, and its radio
transmitter sends the logged data to a receiver on a NOAA satellite.
The data is then relayed to me (and Microwave Telemetry, Inc., in
Maryland) via a French company, Service Argos, Inc., which distributes
data from ocean buoys and satellite tags.
If the dart pulls out of the fish and the tag is prematurely released,
or if a fish dies, it will start transmitting the data. The tags
transmit the logged data for about 30 days. We use the light data to
reconstruct the migration path of the fish, as well as its depth and
temperature for the entire time the tag was on the fish. Our
collaborator, Dr. Greg Skomal, of the Massachusetts Division of Marine
Fisheries, was the tagger for this particular fish- which was about 48
inches and released on August 13, 2007.
With these early releases, we know that none of the fish died, but that
the tag detached from the fish. Keeping tags on any marine animal is a
challenge, and usually only a portion of the tags remain attached for
up to a full year. Actually, we were pretty happy to have data coming
in early, because this is the first time anyone has been able to put a
popup satellite tag on juvenile bluefin, and we were anxious to learn
where they would go
after leaving New England waters in the fall. Very little is known
about where they go after leaving coastal waters in the summer and fall
until they show up again the next season.
We start tagging juveniles off Wachapreague, Va., in late June and July
and finish farther north, off Cape Cod and other areas of New England
later in the season. From conventional tagging conducted by fishermen
over the past decades, we know that some of these juvenile bluefin tuna
cross the Atlantic and visit areas such as the Bay of Biscay off Spain.
Since 1997, we've used Microwave
Telemetry's full-size PSAT tag for giant bluefin in New England and
Canadian regions. Until they produced the miniature pop-up, or X-tag,
we were required to use implanted data loggers for juveniles. With our
collaborators, we released 127 juvenile bluefin with tags placed in the
belly cavity of fish. These types of data loggers must be recovered
along with the fish, so they are dependent on a fishermen catching the
fish and returning the tag to us. The PSAT tag does its work without
any intervention, so we get the data back when the tag is released from
Bluefin tuna are an extremely valuable fisheries resource that has been
in the news for months. They are heavily overfished in the
Mediterranean Sea and East Atlantic and by pirate fleets. The fish that
we see in our coastal waters live up to 30 years, and may travel back
and forth across the Atlantic many times, where unregulated fishing may
Despite being one of the most valuable fish in the sea, there are huge
gaps in knowledge that need to be filled -- where do they spawn, how
often, what do they eat, what makes them shift their distributions?
When these PSAT tags are recovered, more data that can't be transmitted
to the satellite can be recovered, so we obtain more details about the
fish. And finally, the best part is that the tag can be refurbished and
deployed on another fish next season. At close to $4,000 each, each tag
is an extremely valuable resource for the LPRC.
To learn more, go to the Web sites: