Reading Comprehension

READING VOCABULARY EXERCISES

Considering the incredible number of between 150-200 millions sharks destroyed each year, we need to look at the natural biology of sharks to fully understand the potential threat of extinction to these species. Most sharks are slow growing, have late maturation and low fecundity and this is the shark’s downfall. They cannot replace their stocks to keep up with human exploitation, such as say, sardines can. Lets look at The Great White Shark. The Great White Shark female takes approximately 15 years to become sexually mature, and the male about 8 years. At these ages the female will be around five meters long and the male around four meters long. The Great White Sharks´ fecundity is low, so the female may possible only give birth to several litters of pups in a lifetime and these litters are relatively small, ranging from about seven to eleven pups in a litter. The white shark is just an example, and if you look at all species, you find some which give birth to only one pup and some such as the Sandbar shark which only become sexually mature at about 25 years old. So due to the shark´s inability to reproduce quickly, stock replacement is not occurring, and subsequently the populations of the world are fast diminishing. In fact they are being wiped out far quicker than most people realise, with many species critically endangered and some species literally on the brink of extinction.

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Many species of shark need protection, but unfortunately, the protection of species is not the end of the problem. Although the protection of that species would be a start in the right direction, it would possibly not guarantee the survival of that species. We have to look further into the complexities of the problems facing sharks, which bring us to our next obstacle, which is probably just as serious as over exploitation. This huge hurdle is Habitat Degradation. More than half of the earth´s human population live within about 100 km of an ocean, and subsequently this ever increasing population encroaches on the inshore marine environment. Costal marine habitats are subsequently adversely affected and altered at relatively accelerated rates by the development of harbours, buildings, inshore fishing fleets, weekend boat anglers and industrial outlets. Humans with modern technology and machinery can alter a complete ecological environment within days, weeks or months. Sharks unfortunately do not have the ability to adapt to these changes in their habitat, and therefore stocks are affected. Most shark species utilise the inshore zone for nursery purposes which obviously indicates that these areas need to be stable. We need to take a serious look at the conservation of shark nursery areas, as it will not be sufficient to only protect the adults stocks. If we are not very careful, we will not only loose our shark stocks, we will lose entire ecological systems.

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Instructions:Read the article. Then, answer the questions according to the reading not according to your knowledge. Q 1-3 Q 4-6 Q 7-9 Q 10-12 MENU

Instructions: Choose the correct answer a,b or c. 1. What is one of the causes of sharks extinction? a. Low fecundity b. Pollution in the ocean c. Lack of food 2. How many sharks are destroyed each year? a. 200 million sharks b. about 180 million sharks c. less than 150 million sharks 3. How many years it will take the female to become about five meters long? a. 8 years b. 25 years c. 15 years GO BACK MENU

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