Sei Whales can be spotted throughout the open waters of Galapagos, but the best place for whale watching is in the Bolivar Channel between Isabela and Fernandina islands. The north western islands of Darwin and Wolf can also be great spots for whale watching, but can only be visited as part of a Galapagos dive cruise.
The best months for Galapagos whale watching are generaly from June to December, when the cold Galapagos waters are at their richest in nutrients.
Seen around the Galapagos in open waters on cruises in groups of one to six, the sei whale dives to shallow depths for short periods of time, rising to the surface to blow streams of water into the air.
Galapagos Sei Whales are the third largest of their kind, and the fastest of the group, able to swim at speeds of 31-mph for short periods of time.
This species are a member of the rorqual family; non-toothed, filter feeders that are found in oceans around the world. Sei whales migrate annually, journeying to the fertile waters of the Galapagos waters to feed and breed in deep, off-shore waters throughout the islands.
The steel gray mammal can weigh as much as 45 tons and measure up to 66 ft. Sei whales have as many as 60 pleats along their throats, allowing them to expand them when they feed. They draw in huge quantities of water into their mouths, feeding on as much as 2000 pounds of krill and small fish each day.
Sei whales are recognized by a signal ridge running from their snout to the unique pair of tell-tail blow holes that all members of the rorqual family share- in front of a dorsal fin that rises up to 21 inches from its body.
Sei whales mate in the winter and take care of their young for 9 months until they are almost 40 ft. in length. They reproduce every two to three years and live up to 65 years old.