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Harbour seals are released in Porteau Cove, B.C., in 2013, after being outfitted with satellite-linked transmitters.ANDY CLARK/Reuters

A series introducing the next generation of innovators. We asked prominent British Columbians to nominate people they're watching.

Nominator: Andrew Trites is director of the Marine Mammal Research Unit at the University of British Columbia. Fisheries managers have long struggled with the question of exactly what impact the tens of thousands of harbour seals on the West Coast are having on salmon populations.

Innovator: Austen Thomas, one of Dr. Trites's PhD students, who may be the first to provide a definitive answer.

"He has been developing DNA techniques to determine proportions of prey consumed by seals, and he has also developed a head-mounted tag that can record the numbers of tagged salmon that seals swallow." - Andrew Trites, director of UBC's Marine Mammal Research Unit

Radio Frequency Identification (RFID) technology is familiar to everyone. You use it when you tap your credit card to pay for an item. But it's also widely used in wildlife tracking, with millions of hatchery salmon fitted with internal passive integrated transponders, or PIT tags, so the fish can quickly be identified with RFID scanners when they are recaptured.

Austen Thomas, whose research is funded by the Pacific Salmon Foundation, said he was at a meeting recently where researchers were discussing the high mortality rate of young salmon and wondering about seal predation.

"We're trying to figure out what's happening to Chinook, coho and steelhead in the Salish Sea," he said, noting that harbour seals have long been suspected of driving down the salmon population.

But Mr. Thomas said it is extremely difficult to determine the impact of harbour seals, because the animals feed on a wide variety of fish, including some species that prey on salmon.

So the question remains: Are the seals damaging the salmon population – and if so, by how much?

In the past, researchers shot seals and studied stomach contents to gain insight into diets. More recently, scientists have analyzed scat. But while undigested fish bones told them generally that the seals were eating salmon, it didn't provide a breakdown of the species, or of the volume consumed.

Mr. Thomas has come up with a way to use RFID technology to flesh out the details.

"It occurred to me that we can put PIT tag scanners on seals and actually quantify the number of PIT tags these seals are consuming," said Mr. Thomas.

Next spring, in Baynes Sound off the east coast of Vancouver Island, Mr. Thomas will fit "seal beanies" with RFID scanners on the heads of 20 harbour seals. At the nearby Big Qualicum Hatchery, he will insert PIT tags into 40,000 coho smolts just before they are released to the sea – and then he'll sit back and wait for the data to come streaming in via satellite link.

Mr. Thomas said the devices, which he developed in conjunction with an engineer from Wildlife Computers and tested at the Vancouver Aquarium, have a sensor that triggers the RFID scanner whenever a seal makes a lunging motion with its head, as it does when feeding. The accelerometer turns on the scanner, which captures the information from the PIT tag as the salmon carrying it goes into the seal's mouth.

"With this we [will] know the exact number of individual fish that they ate," he said. "You'll be able to say what specific watershed that fish came from, and when, and where it was consumed by a seal. It is just crazy to have that kind of information."

With an estimated 40,000 harbor seals in the Strait of Georgia, fisheries managers say it is vital to understand how many salmon they are eating. Next spring, if Mr. Thomas's work goes as planned, they should know.

The beanies, attached by glue, will drop off when the seals shed their fur coats in the fall.

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