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than previously known, see page 44 "A record holder bites her way to freedom"). A well-known nursery is located in the Strait of Sicily, where fish trawlers continually catch young sharks in the middle of summer with trawl nets at a depth of 200 meters. Male great white sharks reach a maximum length of 550 centimeters. Female sharks get bigger and grow older. Sharks five meters in length are about 15-25 years old. According to estimates, the life span ranges up to 60 years. Maximum size and weight are not certain. Sizes of just over 6 meters are scientifically guaranteed. Migrations in the Name of Love Great white sharks cross the world's oceans at a ground speed of 3.2 km/h. Swimming incessantly, they cover enormous distances. Some sharks, especially the large ones, are restless nomads. Oth-ers show a remarkable location loyalty, however, such as the sharks found in the Gaansbai village in South Africa. The individual characteristics of 805 different sharks were recorded on film during a long-term study in the large bay between Cape Town and Cape Agulhas. One hundred twenty three of them were then sighted 1,307 times during a period of more than one year. The record holder is a male shark with 20 observations within about five years. Lady shark Nicole proved, however, that the Gaansbai sharks migrate very quickly and very well when their reproductive instincts drives them to ancestral breeding grounds: Shark P12, named Nicole by scientists in honor of the Australian actress and shark lover Nicole Kidman, crossed the Indian Ocean twice within 9 months, mastering a distance of 19,300 km on its way from South Afri-ca to Australia and back. This was the fastest round trip executed by a marine animal that scientists ever recorded. On average, the shark put back at least 4.7 km/h. Nicole was captured in November 2003 and fitted with a satellite tag. This allowed the researchers to follow the lady shark's 99 day journey from South Africa to Australia. Apart from a slight curve at the beginning of the trip, Nicole covered the route almost directly. The female spent 61% of the 37


Sharks - Free Sample
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