August has been a tremendous sighting month for both Humpback and Blue Whales! Large groups of both species of whales have been sighted on numerous days feeding on massive amounts of krill. Krill is a small shrimplike animal about a quarter inch long and is an important food source for many animals in the Bay, especially the large whales.

Blue Whales in Monterey Bay

The Blue Whale is the largest whale and the largest animal ever to live on earth, reaching lengths of over 90 feet off California! One Blue Whale eats about 4 tons of krill everyday or 40 million individual krill.

Monterey Bay is one of the best places in the world to see these endangered whales, with an estimated 10,000 left in the world. Before whaling there were several hundred thousand Blue Whales but due to heavy hunting their numbers were drastically reduced. However, the population off California is the largest in the world, numbering around 2,200 whales, according to Cascadia Research, a non-profit group that monitors the populations of Blue and Humpback whales off California.

Krill in the Monterey Canyon

Monterey Bay is characterized by the largest and deepest submarine canyon on the west coast and the only one that closely approaches shore. It's similar in size to the Grand Canyon. Also, the central California coast is a prime upwelling zone, meaning deep nutrient-rich cold water near the bottom is driven to the surface by the combination of winds, the contour of the coastline and the rotation of the earth. When this rich water reaches the surface the sun fuels the production of plankton blooms. Krill feed on this microscopic plankton and whales feed on the krill. The krill often concentrate along the edges of the Monterey Canyon, which makes the whales very accessible to our trips departing from the Monterey Harbor. There is nowhere else along the coast where Blue Whales can be sighted so close to shore. Monterey Bay is a special area and is part of the Monterey Bay National Marine Sanctuary.

Blue Whales Feed on Krill

On recent trips we have spotted lunge-feeding Blue Whales, often feeding in groups of two, simultaneously lunging out of the water with their mouths wide open to engulf thousands of krill. Looking closely we can even see the krill spilling out the sides of their mouths. Their massive rows of baleen catch the krill like a filter.

Blue Whales are certainly an impressive sight and often a once in a lifetime chance for those who witness these magnificent creatures. Blue Whale numbers fluctuate in the Bay and are most abundant when the krill is densest. Presence of Blue Whales is hard to predict as it depends on oceanographic conditions, but generally summer and fall in Monterey Bay provide an excellent chance to see the Blues.

Blue whales feed only on krill, whereas Humpback Whales are more opportunistic, feeding on both fish and krill.

Watching the Playful Humpback Whales

Humpback Whales have also been abundant in the Bay, often displaying their playful antics such as breaching, tail slapping, pec slapping, and displaying "friendly" behavior towards our boat. This intriguing behavior by Humpbacks has been increasing in recent years as these endangered whales are fully protected. Sometimes while our boat is just drifting the Humpbacks will swim over and roll around and spyhop next to the boat, often covering everyone with whale breath. This is an incredible sight and those lucky enough to witness it swear it is something they will never forget and often it is the highlight of their vacation, as these whales are curious and trusting enough to approach us on their own.

Scientists Study Blue and Humpback Whales

Blue and Humpback Whales still hold many mysteries and various scientists continue to study them. Biologists on Monterey Bay Whale Watch trips photograph the whales with a telephoto lens to identify individuals by their natural markings. We send the identification photos to Cascadia Research, where they are matched to id photos of known whales or added to the catalogs if they are of new individuals. This method is critical in making accurate population estimates and monitoring the recovery of these endangered whales. So far the news is good and the whales are increasing each year. This summer and fall, scientists will be placing different tags on the Blue Whales including satellite tags, depth recorders, and acoustic tags to learn more about the behavior and movements of the whales.

In addition to abundant whale sightings, we have been seeing large schools of dolphins on many trips. The dolphins cover a large range up and down the coast but frequent the deep waters of Monterey Bay to feed on fish and squid. Seeing groups of over 1000 dolphins of three species is also an incredible experience that occurs often in the Bay. Many people don't realize that just a short distance from one of the most populated areas in California is a vast ocean wilderness teeming with a diversity of large mammals and other marine life that rivals any African safari. For up-to-date information, see our List of Recent Marine Mammal Sightings in the Monterey Bay Region.