N.S. fishermen being asked to look out for a curious catch — ribbon-decorated lobster

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The Department of Fisheries and Oceans is hoping Nova Scotia lobster fishermen can be persuaded to throw back some of their catch this spring. Specifically, any lobsters decorated with a blue ribbon.

The ribbons are part of a large-scale tagging project launched last summer that aims to track movement patterns amid changing ocean conditions.

While previous tagging studies have focused on smaller areas, this one covers a large stretch of Nova Scotia's Atlantic coast, from the northern tip of Cape Breton to an area around Halifax, said Ben Zisserson, a lobster biologist with DFO.

"There really hasn't been, to the best of my knowledge, a real comprehensive tagging project that's gone on across all these lobster fishing areas," he said in an interview with CBC's Information Morning Cape Breton on Thursday.

At the end of last season, biologists tagged about 3,000 lobsters with plastic streamer tags, each bearing its own number.

Snap a photo

DFO is asking fishermen who catch one of the lobsters to snap a photo of the tag with their smartphone and send it to the department in a text or email.

Fishermen are also encouraged to send a photo of their boat's GPS or navigation screen to show the location where the lobster was caught.

Scientists have been looking at the effects of the changing ocean on lobster populations. In 2019, for instance, researchers published a study that tried to predict the impact of warming water temperatures due to climate change on the lucrative Nova Scotia and New Brunswick lobster fishery on the Scotian Shelf

Because lobster stocks are usually managed on the basis of a single fishing area, it's important to know if they're moving from one area to another, said Zisserson. The project will also involve gathering together historical data.

"So much has changed over the last, say, 20 years," said Zisserson. "Ocean conditions have changed. The predator and prey relationships have changed a lot out there. And as well lobster populations now are really at an all-time high, or very close to an all time high, throughout much of the province. So we want to see, with those new conditions, what movement patterns look like with the animals."

Multiple recaptures

The tags are sewn through muscle where the lobster's body meets its tail, said Zisserson.

"And it's kinda neat because when the animal molts it actually takes the tag with it," he said.

It's expected the tags will stay with the lobster over a number of years — as long as the lobster is allowed to stay in the ocean.

"We realize that all fishermen probably won't put them back in the water. But it's a huge help to the project," he said. "If they're able to return them, we can get multiple recaptures of the same tagged animal, and we can really see its movement over its lifecycle."