BP078, A.K.A. “Ligné”

From the newsletter Whale Portraits, July 20, 2018, by Camille Bégin Marchand

Bp078 – nicknamed “Ligné” – is a male fin whale that has been known for over 30 years. Yet he’s never made the front page of Whale Portraits! His dorsal fin is quite short and triangular in shape; his back bears a few lateral scars. Could this be the reason for his nickname? You tell us! Along with Caïman, he is the only other fin whale that GREMM has known since 1986 and that has been observed at least once in the past 5 years. However, his frequency of use is quite different from that of Caïman: Bp078 has been identified only 12 years out of 33, which suggests that this individual frequents other feeding areas than the head of the Laurentian Channel. Under the code F326, Bp078 is also featured in the fin whale catalogue maintained by the Mingan Island Cetacean Study (MICS) , which works mainly in the Gulf of St. Lawrence and off the Gaspé Peninsula.

The fin whale is nicknamed “greyhound of the sea”. Indeed, its cruising speed of 9 to 15 km/h is rather fast for a rorqual. It can even maintain speeds of 28 km/h for short periods and accelerate up to 37 km/h. However, despite these impressive stats, it is not the fastest of the rorquals. The sei whale (very rare in the St. Lawrence Estuary) can maintain a cruising speed of 55 km/h for short periods. The minke whale can reach speeds of up to 38 km/h. The humpback is the slowest of the rorquals, with an average cruising speed varying between 5 and 14 km/h. Maximum accelerations of 25 km/h have been recorded. How fast whales swim varies depending on their activities: travelling, feeding, resting, reproduction period, etc.

Evaluating the cruising speed of a cetacean or other marine mammal is not easy. Tags can be a source of information. A radio tag is used to clock the speed of an individual during a very specific period. For example, we have been able to determine that one fin whale accelerated to 18 km/h while feeding, just before opening its mouth. Radio tags can be used to track the animal over long distances. For example, satellite tracking of humpbacks in the Pacific Ocean during their migration from the Hawaiian Islands to Alaska determined that these individuals were travelling approximately 110 km per day at an average cruising speed of 4.5 km/h. A whale off the coast of Gaspé could reach the Estuary in less than 7 days, as Tic Tac Toe aptly demonstrated last week. The trip must be worth the effort though!