In a series called Deep Trouble, CBC News explores the perils facing the endangered North Atlantic right whale.

Two Canadian Coast Guard vessels were among the six ships fined Monday after being caught violating speed restrictions aimed at protecting North Atlantic right whales.

Transport Canada fined the coast guard ships Cape Edensaw and Cap d'Espoir $6,000 and $12,000 respectively for violating the temporary mandatory slowdown in the shipping lanes north and south of Anticosti Island in the Gulf of St. Lawrence.

Four other ships received fines ranging from $6,000 to $12,000 and the ship's owners have 30 days to pay or file appeals.

Transport Canada said most operators in the shipping industry were compliant and respected the measures, there were exceptions.

Temporary slowdowns

Investigations into other reports of speeding continue.

The temporary mandatory slowdown was implemented June 26. Additional measures such as expanding the slowdown areas were added on July 8.

So far this year, eight dead North Atlantic right whales have been found floating in the gulf.

Just over 400 right whales remain in the world, and ship strikes and entanglement in fishing gear have been blamed for some of the deaths in recent years.

Three of the deaths this year have been linked to ship strikes.

Ships closer to right whales

No deaths this year have been linked to fishing gear, but in 2017, two of the 12 whales found dead in the gulf had become entangled in fishing rope.

Transport Canada said data shows that during the slowdown period, vessels were using more direct routes to get through the Gulf of St. Lawrence instead of using the shipping lanes.

As a result, marine traffic was closer to known whale locations.

"Vessels must transit in a way that does not harm the endangered North Atlantic right whale population," said federal transportation minister, Marc Garneau. "When they exceed the set speed limits, we won't hesitate to issue fines."