The Great White Shark

De­spite its fear­some rep­u­ta­tion, the great white shark is suf­fer­ing fright­en­ingly at the hand of man

Sport Diver - - Dive Briefs - BY DR. RICHARD SMITH

1.

The great white shark gives birth to lit­ters of two to 14 young af­ter a ges­ta­tion pe­riod around 18 months. The young mea­sure 4 to 5 feet in length at birth.

2.

Adult great whites prey largely on ma­rine mam­mals, but ju­ve­niles eat other fishes, small sharks and rays. Ju­ve­niles’ teeth are dif­fer­ent from those of adults to ac­count for this change in diet.

3.

There have been five fa­tal at­tacks by great whites in the U.S. since the turn of the mil­len­nium. Vend­ing ma­chines kill more peo­ple each year.

4.

The IUCN con­sid­ers the great white shark vul­ner­a­ble to ex­tinc­tion.

5.

The great white sharks found off Cal­i­for­nia be­long to a ge­net­i­cally dis­tinct east­ern Pa­cific pop­u­la­tion.

6.

While in the womb, ju­ve­nile white sharks feed on un­fer­til­ized eggs pro­duced by their mother in a process known as oophagy.

7.

The long­est great whites may reach 21 feet in length, three times as tall as Shaquille O’neal.

8.

White shark num­bers in the North At­lantic are es­ti­mated to have de­clined by 79 per­cent since 1986.

9.

Fe­male white sharks leave feed­ing ar­eas and move to nurs­ery ar­eas to pup. Young sharks re­main in these ar­eas for some time, pos­si­bly to avoid can­ni­bal­ism.

10.

The largest shark that ever lived was a close rel­a­tive of the great white. Me­ga­lodon is be­lieved to have be­come ex­tinct some 2.6 mil­lion years ago. At 60 feet in length, it was longer than a Grey­hound bus and fed on whales.

11.

The cen­tral Cal­i­for­nian white shark pop­u­la­tion is es­ti­mated at just 219.

12.

A great white shark was tracked swim­ming 2,500 miles from Mex­ico’s Guadalupe Is­land to Hawaii.

13.

De­spite the great white shark be­ing the most widely pro­tected shark in the world, ge­netic anal­y­sis of fins has shown that they are il­le­gally caught for the global shark-fin trade.

14.

Each in­di­vid­ual’s dor­sal fin is dis­tinct, like our own finger­prints. One white shark off Cal­i­for­nia has been sighted many times over a 22-year pe­riod.

15.

Fe­males reach sex­ual ma­tu­rity at around 17 years of age and 16 feet in length.

Fol­low Richard Smith’s un­der­wa­ter ad­ven­tures at ocean­realm images.com

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