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“Problematic hayawanat”. Azlini binti Hj. Ismail. Aimi Salwani binti Abdul Rahman. Amirah binti Abdul Razak. MUSLIM SCIENTISTS. Introduction. Concept : Documentary. Among the greatest challenges is the accelerating pace of species extinctions.
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Azlini binti Hj. Ismail Aimi Salwani binti Abdul Rahman Amirah binti Abdul Razak MUSLIM SCIENTISTS
Introduction Concept : Documentary Among the greatest challenges is the accelerating pace of species extinctions. Concerning about this matter, we will bring you towards examining biodiversity crisis and its solutions.
Case Study: Whales Overexploitation-
WHALES OVEREXPLOITATION • Whales ,the lasrgest living animal are rare in the world’s ocean today,their numbers are driven down by commercial whaling • Begin at the sixteenth century • Reaching apex at the nineteenth and early twentieth century Why they are hunted? • Whale blubber (whale fat) • make oil from it • The fine lattice-like structure • Use in undergarmnents Chronology Right whales were the first to bear the brunt of commercial whaling. they were slow, easy to capture, and provided up to 150barrels of blubber oil and abundant whalebone
Chronology Eighteenth century-whaler turned to another species(thegray,humpback,bowhead)-lead to number decline>>Turned to blue whale-they also decimated>>Turned to smaller whale(the fin,sei,sperm) Every whale became focus of commercial breeding,its numbers unevitably began to steep decline Action 1935-hunting of right whale was made illegal(their number did not recovered) 1946-formation of International Whaling Comission(continue to steep decline) 1974-number are driven down-IWC banned hunting of blue,gray and humback and institued partial bans on other species) 1986-IWC institued a worldwide moratorium on all commercial killing of whales Some species appears to be recovering while other do not
Case Study: Lake Victoria Cichlids Introduced Species-
Lake Victoria, an immense shallow freshwater sea about the size of Switzerland in the heart of equatorial east Africa, had until 1954 been home to an incredibly diverse collection of over 300 species of cichlid fishes.
These small, perch like fishes range from 2 to 10 inches in length, with males coming in endless varieties of colors.
the problems... • In 1954, the Nile perch, Lates niloticus a commercial fish with a voracious appetite, was introduced on the Ugandan shore of Lake Victoria. • Nile perch ,which grow to over 4 feet in length, were to form the basis of a new fishing industry. By 1986, Nile perch population exploded and the endemic cichlid species were virtually gone. • By 1989, high inputs of nutrients from agricultural runoff and sewages from towns and villages had led to algal blooms. • A normal increase in cichlid numbers due to the algal blooms led to the explosive increase in perch which then ate their way through the cichlids. For decades, these perch did not seem to have a significant impact to the cichlids.
Today, all of these cichlid species are threatened, or extinct. the solution?!!
Restoration of once-diverse cichlid fishes to Lake Victoria. • Removal of the introduced species. + MORAL : larger fishes are better source of food, but we should not harm the nature just to fill human needs.
Case Study: Footed Ferrets Disruption of Ecological Relationship-
DISRUPTION OF ECOLOGICAL RELATIONSHIPS-BLACK-FOOTED FERRETS The black-footed ferret (Mustela nigripes) is a highly specialized predators,prey on prairie dogs Chronology A century ago -at north America range,agricultural development destroyed 1.their prairie habitat 2.prairie dogs on which they feed Late 1970s -the black-footed ferrets was thought to be gone extinct when the only known wild population;a small colony in South Dakota died out 1981 -a colony of of Meeteese,Wyoming was located(left undisturbed for four years-number dropped by 50%)
Actions • -A decision was made to capture some ferrets for a capture breeding programme • -effort to capture all remaining ferrets • 1991-great succes-population jumping to 311 individulas • Reintroduction-44 ferrets • 1993-Additional 159 were released(having drastic decline) • 1998-only 10 individulas are still alive • The reason of decline is not completely understood but predators such as coyotes appear to have played arole • Current attemps involve killing local coyote • The black-footed ferrets still teeter at the brink of extinction
Case Study: 6 2,000 25,000 Prairie Chickens Loss of Genetic Variation
The great prairie chicken (tympanuchus cupido pinnatus) is a showy 2-pound wild bird renowned for its flamboyant mating rituals. Prairie grasses in Illinois
Prairie Chickens- Prairie Chickens- Prairie Chickens CASES: Introduction of the steel plow in 1837 Permeates into deep root system in prairie grasses Habitat Loss EXTINCTION Prairie Chickens- Prairie Chickens- Prairie Chickens- Prairie Chicken
Prairie Chickens- Prairie Chickens- Prairie Chickens FIRST TRIAL: 1962,1967- sanctuary was established. But, they were not doing well. Their numbers kept falling. SOLUTIONS: SECOND TRIAL: 1992 ,1996- Out-of-state prairie chicken were brought in to interbreed with the Illinois birds, and hatching rates were back up to 94% by 1998 PROBLEM: 1)Population sizes were too small 2)Mating rituals; one male dominate a flock Loosing genetic variability Prairie Chickens- Prairie Chickens- Prairie Chickens- Prairie Chicken
Case Study: Songbirds Habitat Loss and Fragmentation
The songbirds are long-distance migrants and covers species such as thrushes, orioles, tanagers, catbirds, vireos, buntings, and warbles. • These birds nest in northern forests in the summer, but spend their winters in South or Central America or the Caribbean Islands.
the problem... • Fragmentation of breeding habitat and nesting failures in the summer nesting grounds of the United States and Canada have had a major impact on the breeding of woodland songbirds. • Many of the most threatened species are adapted to deep woods and need an area of 25 acres or more per pair to breed and raise their young. • As woodlands are broken up by roads and developments, it is becoming increasingly difficult to find enough contiguous woods to nest successfully.
-the solution- MEGARESERVE • Critical ecosystems – Core zone. • Research and tourism – Buffer zone. • Sustainable resource harvesting and permanent habitation – Multiple use area. Refer to page 645 Biology, Raven.
Conclusion Endangered species are accelerating towards extinction, then who cares about it? Abu Hurairah r.a is a Companion who loved cats until he is called; “the cat lover” Progressing with development, but if that only beneficial to human, we are cruel vicegerence.