Monday, March 3, 2008

Tigers

Name: Panthera tigris
Genus: Panthera
Conservation status: Endangered


South China tiger
Tigers are the largest species of cat on Earth today, also one of the most popular types megafauna. Instantly recognizable by their fur, ranging from a reddish-brown to yellow in colour on their upper body and a whitish colour on their undersides. Each tiger with their unique, signature black stripes. They can reach up to about 100 to 384 kg in weight and 1.4 to 2.8 m in body length (not including the tail) depending on which sub species of tiger they are. Known to live up to around 15 years in the wild and about 17 in captivity, although the oldest tiger has lived up to 26 years.
They can be divided into nine subspecies, Bengal tiger, Indochinese tiger, Malaysian tiger, Sumatran tiger, Siberian tiger, South China tiger, Balinese tiger, Javan tiger and Caspian tiger. The later three sub species have died out due to harmful human activity.

In the past tigers occupied nearly all of Asia, but by the 19th century they became extinct to the western half of Asia and now only remain in the South East. Although tigers require somewhat dense vegatation or coverage in order for their camouflage to sufficiently conceal it, they are one of the more adaptable creatures, their wide range of habitats including tropical and evergreen forests, grasslands, rocky countries, mangrove swamps, river woodlands, savannas and occasionally mountain ranges. They are usually found in countries such as Russia, India, Siberia, Afgahnistan, India, China and South-East Asia. Tigers are generally solitary and highly territorially animals, requiring large amounts of land to support their needs in terms of prey. Usually, is about 60-100 km squared for males and 20 for females. Even with overlapping territories, tigers tend to avoid confrontation with others, when they do ( if not for mating ) it almost always results in the death of one of the two. Suprisingly, they don't seem to mind the sharing of their prey with the opposite sex or even the same.



Tiger distribution




Tigers are the top carnivore of their food-chain favorite prey beeing deer and wild boar but eating most medium sized animals and some smaller prey. Unlike we might think, they have also been known to consume grass, berries and fruit along with their daily catch of meat. To catch their prey, they rely on concealment, using their eyes and ears to determine it's location . In a crouching position it stalks it, until they get into a close enough range to pounce and overpower their prey with their strength and body weight. If the animal is fairly large they will bite on the underside of it's throat to suffocate it, with smaller prey they bite the nape usually breaking the spinal cord, piercing the windpipe and possibly severing an important artery. Tigers unable to hunt as well often become man-eaters.

As for it's role in it's ecosystem, one of the only things it might produce is it's waste, mabye fertillizing plants or serving as food for some insect or small animal. It's main part in this system is keeping the populations of other animals in check which might or might not be a problem if left to reproduce in large numbers. The effect it would have were the tigers extinct would be that without the tiger killing all of the animals it does for food they will become greater in numbers. The competitors of the tiger will also in turn increase in number due to their wider variety in prey. Either one of these could become a pest. In a worst case scenario, these animals over run their habitats and consuming vegatation to a rate where it doesn't grow back fast enough to support such a large amount of fauna resulting in some of these animals to either starve or search other means of food, which could be in the human populated areas. The lack of vegatation would result even more land degradation and greenhouse gases.
Today there are less than 6000 tigers alive in the wild. They are the third on the list of most endangered animals. This is mostly due to a few reasons. The first would be habitat loss. Over 80% of Asia's forest have been lost in the past centuries. While human need for timber and living space increases the forests become fragmented and slowly dissapear. Also toxins in the air and water caused by pollution make otherwise healthy seeming habitats inhospitable. Either way a tigers neccessary resources are eventaully going to disenagrate. Another cause behind the endangerment of tigers is poaching. Their bones and organs are said to have mythical medical properties and are sold on the black market. Their pelts are a symbol of nature's power and beauty, often kept as trophies. When caught, tigers are put in small cramped living spaces where they are shot or skinned alive. Even so, the profit from selling tiger body parts still heavily out ways the fine for having killed one, which is most likely why about 1 to 5 tigers are killed each day. Interbreeding depression is the last main reason. This occurs when tigers can't find other tigers to breed with because of habitat fragementation and are forced to breed with the same small group repeatedly. This allows the gene pool to weaken and causes many birth dfects and mutations, leaving us with a tiger population that is hardly genetically stable. In summation, tigers are a barely surviving species that will become extinct if we do not take some course of action.


Tiger cut in half after capture

To keep tigers from dying out completely we should try to preserve as much of their habitat that is left as environmental reservations and perhaps start plantations to possibly renew some of habitat that has been lost. Another idea would be to breeding tigers in captivity, preventing interbreding and the weakening of the gene pool and release them back into the wild. Also we might want to start breeding the prey of tigers, so that when they become scare they too can replenish in numbers and provide food for them. Lastly the laws and restrictions on poaching must be enhanced. This has actually been proven to reduce the number of deaths. Mabye if we can do all this, tigers will continue to flourish.





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Red Pandas

Red pandas, along with most other pandas are one of the most endangered species on earth.They are native to the southern parts of Asia, mainly in areas such as Bhutan, China, India, Lao Peoples Democratic Republic, Myanmar, Nepal. Their habitats are often at the foot of moutain ranges where they can easily access their main foodsource, bamboo.They can be recognized by their soft reddish brown fur covering the top of their body, black fur on the lower parts and their unique facial markings.Due to the fragmentation of their habitats, small numbers in their population and need for a special sorts of food. Not only that, but because of some cultural beliefs Red Pandas in areas of China are often hunted for use of their fur. Because of this they are rated Endangered on the IUCN Red List of Threatened Species.Source: http://en.wikipedia.org/wiki/Red_Panda