Friday, April 18, 2014

Ask an Expert: Whales in the Sea of Cortez

One third of the world's whale species are found in the Sea of Cortez/Gulf of California.  Here are two of the whales you will be most likely to see on your Sea of Cortez kayaking tour with Sea Kayak Adventures, Inc.

Blue Whale

Balaenoptera musculus

The blue whale is an enormous animal, larger than any dinosaur that lived on the earth.  We are humbled in their presence not only because of their great size, but because we know so little about them. To encounter a blue whale is the pinnacle of the whale-watching experience.  It is simply the greatest of the great whales.  From January through April look for spectacular sightings of blue whales in the warm, calm waters near Loreto on our Sea of Cortez Islands tours. The following video of these amazing animals was taken by SKA in February of 2011:

Blue Whale Facts

•    The blue whale is the largest animal ever to live on earth.  The largest dinosaur ever to walk the Earth topped out at about 100 tons; this leviathan typically is larger by half. In every dimension their size is incomparable.  They can reach up to 100 feet (33 meters) long and weigh more than 150 tons.  Their tongue alone weighs the same as an elephant.  Its heart is the size of a Volkswagen Beetle, and some of its blood vessels are so wide that you could swim down them.  Its tail alone is the width of a small aircraft’s wings.  Its mouth is large enough to swallow a railroad boxcar and its stomach could hold 8,000 hamburgers.  Their brain weighs 4,500 grams (10 lbs).  24 elephants equal 1 blue whale.

•    The blow holes of a blue whale are exceptionally large – the size of a small child.  When they exhale, the thunderous, dense blow reaches 30 feet high and, on a quiet day, can be heard miles away.

•    Like other rorquals, they have ventral pleats running from the tip of the lower jaw back to the belly, and a small (1 foot high) sickle-shaped dorsal fin located far apt on their back.   The blue whale is blue-gray in color with light mottling.  Broad, flat, U-shaped rostrum (when viewed from above).  Huge, sleek body.

•    The ocean’s largest inhabitant, the blue whale, feeds almost exclusively on one of the smallest: shrimp-like creatures just a centimeters long called krill (euphausids).  Gathered in huge clouds in the upper water column, krill stain the sea red.  A single blue whale in a day, can consume 40 million of them - an astounding 4 tons or more. As a baleen whale, it has a series of 400 three ft long fringed overlapping plates hanging from the upper jaw. Baleen consists of the same material as your fingernails (keratin) and was the “whalebone” used in 19th century corsets.  During feeding, large volumes of water and food can be taken into the mouth because the pleated grooves in the throat expand.  As the mouth closes water is expelled through the baleen plates, which trap the food on the inside near the tongue to be swallowed.

•    Calves are 23 to 27 feet long at birth and 3 tons.  During the nursing period of 7 – 8 months, calves consume 100 gallons of the fat-rich milk each day and gain 200 pounds per day.

•    The blue whale makes deep and low-frequency sounds that travel long distances through water, allowing blue whales to communicate with each other over hundreds of miles of ocean.  This is the most powerful sound produced in the animal kingdom.

•    Blue whales remain on the surface of the water an average of 8 to 10 blows prior a dive which can be as long as 20 minutes.  Its streamlining enables it to cruise along at about 12 mph (19 km/hr), but can sustain speeds of 30 mph (48 km/hr) if frightened or chased.  It is one of the fastest animals in the sea.  The blue whale lifts its tail fluke out of the water on its dives.

•    Blue whales migrate to high latitudes during the summer and to tropical-to-temperate waters during winter months to mate and give birth to calves.  They can feed throughout their range.  Despite their enormous size, we know very little about them.  Their migration routes remain a mystery and we have absolutely no idea where they go to breed.

•    Up to 99% of blue whales were killed during whaling efforts in the first half of the 20th century.  Presently, there are an estimated 3-4,000 blue whales in the Northern Hemisphere.

Whale Tail

Fin Whale

Balaenoptera physalus

The fin, or finback whale, at 70 tons, is second only to the blue whale in size and weight.  It is one of the rorquals, a family that includes whales with a dorsal fin and throat grooves that expand when the animal is feeding.  Beautifully streamlined, Fin whales are among the fastest of the great whales, leading to its description as the “greyhound of the sea”.  This combination of speed and size makes the fin whale a voracious hunter of schooling fish.  From December through May you can see resident fin whales on our Sea of Cortez Islands tours.

Fin Whale Facts:

•    Fin whales, although smaller than the blue whale, can still reach a length of 80 feet and weigh 70 tons.  It has darker skin and a larger dorsal fin (2 ft tall) than the blue whale.  Rostrum V-shaped and flat (when viewed from above).  Distinct ridge on back from dorsal fin to broad triangular flukes.  Dark gray color with light undersides, pale chevron on dorsal neck surface.  Dorsal fin appears shortly after blow.  Dorsal fin shape is falcate with blunt tip and steep backward angle.

•    Unlike blue whales, fin whales do not fluke (lift their tail out of the water) when they dive.  The fin whale’s blow is 20 ft tall and shaped like an inverted cone, and the dive sequence is 5-8 blows approximately 70 seconds apart before a long dive.  They can dive to a depth of 1,800 feet (550 meters).

•    Fin whales are generalists, feeding mainly on small, shrimp-like creatures called krill and schooling fish.  They have been observed circling schools of fish at high speed, rolling the fish into compact balls then turning on their side to engulf the fish.  They can consume up to 2 tons of food a day.  As a baleen whale, it has a series of 475 two ft long fringed overlapping plates hanging from the upper jaw, where teeth might otherwise be located. These plates consists of a fingernail-like material called keratin that frays out into fine hairs on the ends inside the mouth near the tongue.  During feeding, large volumes of water and food can be taken into the mouth because the pleated grooves in the throat expand.  As the mouth closes water is expelled through the baleen plates, which trap the food on the inside near the tongue to be swallowed.

•    Fin whales migrate to subtropical waters for mating and calving during the winter months and, to the colder areas of the Arctic for feeding during the summer months.  Like blue whales, they produce powerful sounds that can carry vast distances in the water.

•    As blue whales became depleted in the first half of the 20th century, whalers turned to hunting fin whales until the whales were placed under full protection in 1966.  Presently, there are an estimated 40,000 fin whales in the Northern Hemisphere

Sea Kayak Adventures