Seals not having a significant impact on lobster bait stock, says DFO

With mackerel and herring fisheries, key sources of bait for lobster fishermen, shut down this spring, some lobster fishermen are casting the blame on growing seal populations in the Gulf of St. Lawrence.

P.E.I. lobster fisherman Charlie McGeoghegan suggested targeting the fishery is the wrong approach.

"If you look at the quotas, they've reduced the quotas every year and it hasn't helped the stock. Well, that's because there's another factor that's causing the problem," said McGeoghegan.

"The seals have caused this problem and DFO has ignored it for over 25 years, because we've been telling them the whole time that their population is exploding and we know what they eat, based on science. They open them up and we know that they eat herring and mackerel and lots of it."

Seal diets are seasonal

In a statement sent to CBC News, The Department of Fisheries and Oceans said its most recent research shows seals are not having a significant impact on herring and mackerel stocks.

Mike Hammill, a marine mammal biologist with DFO, said the science is more complicated than McGeoghegan suggests.

Seal diets are seasonal, as are their migratory patterns. Harp seals, for example, spend their summers in the arctic. During their winters in the Gulf of St. Lawrence mackerel have migrated south to warmer waters. It is difficult to draw conclusions from finding a lot of herring and mackerel in a seal's gut at any particular time.

"In some periods it could be quite intense, but when you look at it overall it's probably only about 10 per cent of their diet is herring and maybe 10 per cent or less is mackerel," said Hammill.

"There is some impact. The big problem is trying to actually put a number on it, and then you have to decide well is it a major source of mortality or is it something that is a little bit more in the background noise."

The population of both grey and harp seals appear to have stabilized in recent years, he said.

Hammill noted there are commercial hunts for seals, but these are much smaller than they used to be.

"The challenge remains markets, I believe, for the industry," he said.

"It's hard to justify killing animals just to kill them."