Posted on 09/17/2021 4:19:54 PM PDT by Capt. Tom
An autonomous ocean glider was disabled by a shark attack Sunday night near Sable Island, abruptly ending a scientific mission and putting the vehicle out of service for months.
The wave glider was 200 kilometres off the coast of Nova Scotia listening for tagged halibut.
"We lost communication with the rudder module, so we were no longer able to steer the glider, so it was drifting freely," said Richard Davis, manager of the glider group at Dalhousie University. "But we still had communication with it. We knew where it was all the time."
An emergency 76-hour effort was undertaken to retrieve the glider which revealed teeth marks and punctures all over what is called the "thrudder," a combination thruster and rudder.
A close-up of the rudder and thruster shows the damage incurred after a Sunday shark attack. (Paul Poirier/CBC) The glider was returned to a Dalhousie facility on the Dartmouth waterfront. Fred Whoriskey of the Ocean Tracking Network examined the bite marks and swabbed the damaged area for environmental DNA traces in an attempt to "figure out who the culprit is of this particular attack on this innocent autonomous vehicle."
"It must have been a pretty big and powerful shark because it managed to penetrate three millimetres or more with teeth marks into the aluminum base of what's solid aluminum," said Whoriskey.
Identifying the culprit He said the shape of the bite marks rules out a porbeagle. He thinks it was most likely a mako or great white shark because they're regularly in the area.
Whoriskey said it might even be a tiger shark, which is cold-blooded. He said they tend to come up later in the summer when the water has warmed up.
It's unclear what prompted the attack. Noise from the propellers or electronic signals may have attracted and irritated the shark. It could have been a taste test to see if the glider was food.
"The third possibility is if you look at the colour of the machine, this is what in the industry they call yum yum yellow," said Whoriskey. "It is a high-contrast thing and can tend to excite an attack under some circumstances."
Fix will cost about $25K The attack has put the glider out of service until a new rudder system can be secured, which will likely cost around $25,000, said Davis.
"It's a pretty big deal," he said. "I don't budget for that. We do have a contingency fund, but it's not small change."
Davis hopes the glider will return to the water this year, but said the COVID-19 pandemic has slowed down getting equipment from suppliers.
Why the glider was in the water The damaged wave glider belongs to Environment and Climate Change Canada and is on long-term loan to Dalhousie University.
It was deployed about three weeks ago near a large underwater canyon known as the Gully as part of a project to monitor the movements of Atlantic halibut tagged by DFO earlier in the year.
It was also measuring meteorological and oceanographic conditions, and sending that data back to shore in real time for use in weather forecasts and climate modelling.
Fred Whoriskey is the executive director of Dalhousie University's Ocean Tracking Network. He's ruled out the culprit as being a porbeagle, but says it might have been a mako, great white or tiger shark. (Paul Poirier/CBC) Davis said he believes there have been more gliders in the Atlantic Ocean this year than ever before, meaning more shark strikes are possible.
"If we do start to see a pickup, we're going to have to find some mediation strategies as to how to reduce this kind of thing, because a valuable mission was truncated ... but what those measures are at this point, I don't know," said Whoriskey.
I post this because one of our East coast white sharks could be the culprit. I would expect a positive ID of the species involved in a few days after several other people look at the tooth mark damage . -Tom
And this was right where I was going to launch my sea lion raft.
“The third possibility is if you look at the colour of the machine, this is what in the industry they call yum yum yellow,” said Whoriskey. “It is a high-contrast thing and can tend to excite an attack under some circumstances.”
—
Not to self. Don’t wear yum yum yellow swimming trunks.
Just go down to Cape Cod and launch it at Nauset Beach. -Tom
Sharks are angry because they got all them teeth...
And no toothbrush. 🤪
Amazing story, I had never heard of an ocean glider before and was wondering what it was when I read the headline.
Nice image of one posted by TexasGator in post #3. -Tom
Well he’s obviously not a lawyer. Sharks leave lawyers alone - Professional Courtesy
Why was the ocean glider out there?
For the halibut.
ICWYDT
I hope he didn’t get the ‘rona! He should maintained his social distancing.
bad shark.
Pffft! They’ll be fine in my lake.
We’re gonna need a bigger glider.
It sounds like an insurrection.
Sharks do’t get enough privacy?
That might be a factor.
I wrote a shark article a few weeks ago which will be published shortly. In it I mentioned some of my pet peeves on how white shark article writers bombard readers with statistics on how unlikely they are to be bitten and how the attacks are mistaken identity.
Here is an excerpt below from my latest article that might explain that attack on the "Ocean Glider".
It could be "territorial protection", or "aggravation" about an intrusion into the sharks territory.. You might be seeing that when boats, surfboards, paddleboards, kayaks, buoys, bathers, surfers and other white sharks are bitten.
Were they intruding into a sharks territory?
The jugged fish is halibut.
https://getyarn.io/yarn-clip/8f89b34a-370c-4d47-807b-f259ec962ff9
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.