We just ran into a group of Fin whales, the second largest of all whales after the immense Blue whale. Big tall spouts are all around, and soon we are all on deck enjoying the views of those large whales as they swim close to the ship.
Despite their huge size, reaching 20 to 25 mts in body length, this species is also known with the nickname of “greyhound of the seas” as they are the fastest swimming great whales. An interesting and unique feature amongst the marine mammals, and pretty useful for their identification, is their asymmetrical colour pattern in their left and right sides of their bodies. This is more obvious in the head, with their right side and lower jaw being lighter than their left side. We reached a high productivity area south of the Antarctic Convergence, attracting groups of Fin and Humpback whales, and even more interestingly though much less spectacular, one of the rare beaked whale is also spotted between its much larger relatives.
Fin whales normally use offshore areas close to the interface between the continental shelf and the slope leading to deep waters, while Humpbacks prefer Continental shelf and shallower waters. Probably the large group of between 10 to 15 individuals that we spotted (including a small calf, recently born warmer waters) were on their way South to coastal Antarctic waters. The migrations of this species are pretty well known if we compare them with the relatively unknown migrating and breeding habits of the larger Fin whales.
Global populations of Humpback whales can be separated on three big groups, the North Atlantic, North Pacific and the Southern Ocean one. If we have a closer look at the latest, we can divide this big population on several sub-populations, being the one named “G” the ones that use tropical Pacific Ocean waters around Colombia, Costa Rica, Ecuador and even Panama for mating and giving birth, and then migrate to the Western Antarctic Peninsula during this time of the year, towards their feeding areas. Individuals from this sub population can be also seen in the Southern Chilean channels, using them as an alternative feeding ground to Antarctica.