AprilJanOctJuly Northern hemisphere Southern hemisphere o -23 o N and S 23 o -43 o N and S

AprilJanOctJuly Northern hemisphere Southern hemisphere 0°0° 20°N 40°N 0 o -23 o N and S 23 o -43 o N and S Number of shark attacks per year 0°0° 20°S 40°S 60°S

A coral polyp is a tubular saclike animal. Coral colonies vary in size. Some corals form only small colonies. Others may form colonies several feet (a few meters) high. Star coral (Montastrea annularis) colonies reach an average height of 10 to 13 ft. (3-4m).

The world's first coral reefs occurred about 500 million years ago, and the first close relatives of modern corals developed in southern Europe about 230 million years ago. By comparison, the Great Barrier Reef is relatively young at just 500,000 years old. The existing reef's structure is even younger; less than about 8,000 years old.Great Barrier Reef is relatively young Reefs grow horizon- tally once they reach sea level

Hard (stony) corals (Order = Scleractinia) have six (or a multiple of six) tentacles on their polyps. They have an internal limestone skeleton. Soft corals (Order = Alcyonacea) have eight tentacles on their polyps. They are soft or leathery in texture and have limestone sclerites instead of a solid sketelon). Soft corals are closely related to gorgonians (sea fans)

Most newly-settled corals contain zooxanthellae (pronounced zo-zan- thel-y), the single-celled algae that live inside the coral animal and help to supply it with food. Providing enough light for the zooxanthellae is one reason why most corals are found only in clear, shallow water. As the coral grows, the polyp divides repeatedly and produces more skeleton. The way the polyp grows and divides will determine the shape of the new coral colony. Growth is initially slow, so that after one year, the coral will still be quite small, perhaps 1 cm in diameter. After the first year, growth is more rapid, and a staghorn coral (Acropora) can increase in diameter at more than 15 cm per year.

An atoll off the coast of Belize

Maldives

Natural pigments in coral tissue produce a range of colors including white, red, orange, yellow, green, blue, and purple.

Bergen Fjords, Norway

Misty Fjords, South East Alaska

Kenai Fjords, Alaska

The “Great White Shark” is widely distributed throughout temperate and subtropical regions of the world's oceans

Unprovoked white shark attacks worldwide (n = 235) Fatalities worldwide from unprovoked shark attacks (n = 61)

White Shark Attacks as a Function of Victim's gender (WORLDWIDE: N=248)

TEMPORAL TRENDS IN THE FATALITY RATES OF SHARK ATTACKS ON DIVERS

Fatalities per attack Number of attacks Both, the frequency of attacks on divers and the proportion of fatal attacks on divers, show declining trends.

THE DIVING ACTIVITIES OF THE VICTIM (N=281) THE ACTIVITIES OF SHARK ATTACK VICTIMS, AS A FUNCTION OF DECADE (N=1459)

Sea surface conditions at the sites of shark attacks on divers

FATALITY RATE AS A FUNCTION OF ATTACK DEPTH DEPTH OF ATTACKS ON SCUBA DIVERS (N=55) DEPTH OF ATTACKS ON SNORKELERS AND FREE DIVERS (N=128)

Blacktip reef shark Blue shark