Using Stable Isotope Analysis to Understand the Migration and Trophic Ecology of Northeastern Pacific White Sharks (Carcharodon carcharias)

A Guadalupe shark - sans tag for now

Hooray for the team at TOPPS. Producing, after many years of careful research and non invasive tagging, a veritable treasure trove of white shark migration info.

Fortunately for the rest of us who are not out in the field year after year struggling with meager research funds, the bureaucracies of California, and a few sad sack high visibility research carpetbaggers who drop into well known research sites to conduct ethically questionable but highly entertaining drilled fin tagging - this data is awesome.


Awesome as in, "take a break boys, you done good" kind of data, and best of all it is open source.

As you can tell we kind of disagree with Da Shark
on this one. Mark your calendars this makes a twice in a lifetime event:

"Needless to say, I very much look forward to finding out how this dovetails with Michael Domeier's multi-year tracking results, and his own interpretation of the data!"

To that statement we say, "Feh!"

The TOPP's team are good folk, they work hard, they produce data and they actually care about the critters that they have spent over two decades getting to know and study.

Once again a well deserved kudos to the whole team. So put the kettle on, pour yourself a big cuppa Joe and sit back and admire the results of long term invested research on California white sharks.

Using Stable Isotope Analysis to Understand the Migration and Trophic Ecology of Northeastern Pacific White Sharks (Carcharodon carcharias)

Note: Stay tuned, as of 2012 Shark Diver in tandem with other operators at Isla Guadalupe will be documenting drilled tags on white sharks. If these tags begin to degrade dorsal fins in the same horrific manner as we have seen in South Africa - there will be hell to pay.

To those who have tagged these animals and are currently parading around the world scene like the second coming of Shark Jesus we are putting you and your tags officially on notice.

Where the Salmon sharks are, now with 20% more research

In 2004 I was fortunate enough to get face to face with the Salmon sharks (Lamna ditropis) of Gravina Bay in Alaska on a private shark diving adventure on board the M/Y Triton that we set up.

These critters are the sporty little cousins of the white sharks and not much is known about them, by sporty I mean jumping out of the water and tearing up local shoals of salmon kind of sporty - fun to watch.

So it was with great interest that I read about regional aggregation sites of these amazing animals in British Columbia in and around Haida Gwaii, in Queen Charlotte Sound this week.

In a paper published last year, and tabled last week with the Cohen Commission in Vancouver, Dr. Williams states an estimated 20,000 blue and salmon sharks gather in a relatively small area each summer.

That's a lot of sharks. Of course there's been some stunning tagging research done on these animals in the region, but you might never know about it because this team does not have a television show, nor do they seek the limelight like a "moth to a flame" as some do in the shark research community.

When it comes to shark researchers we prefer the quiet professionals, they just seem to be more...credible.

White Shark Tagging-SPOT Tags

Very cool white shark tracking data coming from Dr. Salvador Jorgensen's shark team out of Monterey.

What we know and what is being learned about y.o.y (young of the year) is rewriting the book on the entire Western Pacific white shark story:

Dr. Salvador Jorgensen, a postdoctoral researcher at Stanford University's Hopkins Marine Station and the Monterey Bay Aquarium, belongs to a group which tags and monitors White Sharks.

Dr. Jorgensen has provided us with the SPOT tag track which was attached to Monterey Bay Aquarium's most recent White Shark resident. June 25th was the last time the research team heard from the SPOT tag. Dr. Joregensen says this is possibly because "water temperatures have increased and the shark may be avoiding the surface, or possibly the tag is no longer working. We can't be sure."

Editors Note: The Sea of Cortez is turning out to be a major player in the long term health of the great white shark population and long term survival of the entire species in the Pacific.