Previous highlights from the front page of this website

Navy ship, Atlantic Ocean off DelawareA Navy helicopter squadron saw the incredible creature (see photo below) in the water about 200 miles off the coast of Delaware.  What kind of shark is it?

The story, as recounted by the pilot who wrote to us:
"The scene was a little surreal as the fog was thick and our two ships were moving in and out of the fog banks.  The water was really glassy and clear which surprised me.  As we were waiting for the ships to move out of the fog so we could land, we were surprised by how many dolphins were out in the water.  I would say I saw anywhere between 20 and 40 dolphins swimming in various sizes of pods.  This totally amazed me, as I have only seen dolphins when surfing or paddleboarding at the beach.

"As the fog cleared out and we started transferring cargo between ships, we were flying much lower over the water.  I noticed the dorsal fin first and thought to myself that fin is WAY too big to be a dolphin, and told the other pilot, "I think that's a shark!"  We flew over to take a closer look, and sure enough it was.  After circling over once we pulled out the camera and pulled into a hover.  None of us could believe the size...  We ended up hovering next to the shark at 20 feet and it looked to be about half the size of our helicopter -- which is a little more than 60 feet long."  (July 2010)

Ready?  Here it is ...

Great white or other?
What kind of shark is this?  Length estimated at 30 feet ... (click photo to enlarge)

Although it's possible this was a white shark, at 30 feet it would be perhaps the largest on record.  Chances are it was a basking shark, which can get as big as 40 feet.  Basking sharks migrate long distances and feed at the surface.  One of three species of very large krill feeders, their jaws unhinge to produce a gaping mouth with hundreds of tiny teeth.  Click here for more information and to watch a great video of basking sharks swimming and feeding.

Cardiff Kook prank
The Cardiff Kook statue temporarily engulfed
by a papier-mache white shark

The ocean water lapping the San Diego beaches has been dropping as low as 57 degrees. 
For the height of summer, it's extremely cold.  The water has been extraordinarily chilly since July, with only a brief spike in early August.  On Sunday (8/15) a great white shark was spotted off La Jolla Shores.  It was said to be longer than the 12-foot kayak being paddled by the person who saw it.  What is going on?

"They've always been here," people are saying.  Lifeguards warned ocean users about the sighting (actually two sightings -- 9:30 a.m. and 5 p.m.) and urged the exercise of caution and judgment about getting in the ocean.  A damper was the frigid water temperature (not even 60 dF) and the heavy cloud cover (caused by a cold ocean at this time of year).  The morning sighting was reportedly 2 miles off shore (is that really signficant? I wondered), and the afternoon sighting was a mere 50 yards from Tower 30 at La Jolla Shores.

While it's true that sharks are "out there," it's not exactly common to see adult specimens swimming around San Diego beaches in the summertime.  This website explains some of the recent changes in the habits of Pacific Coast white sharks.  Some clues to the presence of GWS adults in our midst these days may be (1) the enormous pinniped population (400,000 seals and sea lions) on California shores, and (2) the cold ocean current, which is right in the "comfort zone" of adult white sharks.  In addition, there has been a heavy algae bloom all summer long, turning the water a bright yellow green with little visibility.  (It's called tetraselmis, and doesn't usually proliferate this heavily.)

Tetraselmis algae, Carlsbad CA
Tetraselmis algae bloomed profusely in Southern California
in July and August of 2010
(photo by Kristina Rebelo)

White sharks have good marine vision, but not in murky water.  A mature white shark's preferred food is the pinniped (young adults eat seals, bigger adults eat sea lions).  And cold water with lots of food is a nice hangout for big white sharks.  La Jolla has busy beaches full of bathers, swimmers and kayaks, as well as plenty of lounging seals.  Where the prey is, the predator follows. Put the murky water together with a food supply, cold temperatures, and people-activities unfamiliar to a shark, and you may get the formula for an up-close-and-personal visit ...  Read through the site and you'll understand how it all goes together!

See our Navy Warfare Testing section for more about the strangely cold water.