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Collage above: From top left clockwise: South China (photo by savechinastigers.org), Siberian (photo by saucy_pan), Sumatran (photo by Silvain de Munck), Bengal tigers (photo by Gilberto Mellaci Netto)9
As
a
subject the tiger is big and important so this page
is very big.
It has to be.There are over four hundred
thousand2
web pages on this animal on the internet at Nov. 2009. In order to get
the page noticed it has to be complete. But where do we start when
discussing this wild cat? We have to prioritise. In everyone of the 400
thousand pages
on the internet about this wild cat there is almost certainly a
description of the animal yet it is the most well known animal after
the human in the world. A description is not therefore a top priority
particularly when the very survival of this animal is in jeopardy in
the wild. Accordingly, the top priority is its status in the wild
because it is endangered. It's survival is threatened. And we don't
want to lose the tiger in the wild, which is the way things are
heading. So after setting out the various subspecies
referred to above, I
start properly with the threats to this magnificent animal and the
attempts at its conservation.
Next I discuss this cat's lifestyle in
some detail and that includes its ecology and behavior, its
distribution and its reproduction. Oh, and finally its appearance...Tiger SubspeciesI have mentioned them above. Their scientific names are as below. The links go to pages on the individual subspecies:Panthera tigris ssp. altaica - Siberian or Amur tiger - see Siberian tiger habitat Panthera tigris ssp. amoyensis - South China tiger Panthera tigris ssp. balica - Bali Tiger Panthera tigris ssp.corbetti - Indochinese Tiger Panthera tigris ssp. jacksoni (after Peter Jackson) (Malaysia calls the tiger: Panthera tigris malayensis after the region) - Malayan tiger Panthera tigris ssp. sondaica - Javan tiger - the most recent tiger subspecies to become extinct. People still claim to see it but are they getting mixed up with the leopard? This tiger is small. It is still feared. And if it still exists it is very unlikely to survive. Panthera tigris ssp. sumatrae - Sumatran tiger - the differences in this tiger in respect of DNA and morphology are such that it has been proposed that it should be a distinct species1. Panthera tigris ssp. tigris - Bengal tiger (new window) - see Bengal tiger habitat - this is the first recognised subspecies7. Panthera tigris ssp. virgata - Caspian tiger (Hyrcanian Tiger, Turan Tiger). It has been decided that this is not subspecies. Differences were due to clinal variation. Most of the hard to spot (to the layperson) variations amongst tigers such as size, skull shape etc. are not "strongly associated with subspecies"7. The variations are continous across the geographic range of the tiger (clinal variation). Only three contemporary populations have been isolated to allow the development of distinct populations. The white tiger is not considered a subspecies. The white or colour diluted coat is the result of a genetic mutation. Interestingly in the domestic cat world of the cat fancy (a group of people who breed and show cats) a genetic mutation of almost any type has been siezed upon as a chance to create a completely different breed of cat. Of course a breed is not a species or even a subspecies. See:
Snow tigers White tiger habitat The South China tiger is almost a paradigm case of the destruction of the tiger generally. It is not only the wild South China tiger that has been destroyed; the management of captive tigers has been of such poor quality that at 2005 only 57 existed and they were inbreed and not purebred! Read more: South China tiger. There would seem to be very little visual difference between the various subspecies but size is one noticeable variable if a visual comparison can be made (which it actually can't or very rarely can). See a description of the Siberian tiger.
Status in the Wild & Captivity - ThreatsIntroductionAs mentioned, three subspecies are extinct - Bali, Javan, Caspian. This topic is all about conflict with humans and persecution by humans. In fact all the treats to the wildcats whatever the size or location are related to conflict and persecution with and by humans indirectly or indirectly and in one form or another. For decades the poachers have been better organised and motivated than the gamekeepers (the conservationists). And that state of affairs reflects the world view on the tiger at 2009. And as the tiger becomes scarcer its value rises, which makes it more desirable to kill it. Is there a tipping point? The tiger has an image as a virile and courageous hunter based on human standards. Cats also are very efficient procreators and are very althetic. They are excellent fighters. Combine all these and people admire the tiger and want a piece of it to try and take from it some of these skills and powers. And when I say take a piece of it I say eat it (tiger bone is very valuable -see for table below7 12). And therein lies its demise. The tiger is the world's top predator except for the human. And the human is frankly in a different league. This is leading to its extirpation in the wild. Poaching in India's tiger reserves is high and for these prices you can understand why.
And on the islands of Bali, Java and Sumatra it would seem fair comment to say that the tiger simply gets or got (for Bali and Java where it is extinct) in the way of human activity. It is still a nuisance in Sumatra and it is given little respect. There is little doubt that the people of these islands (taken as a whole) do not want the tiger in their backyard. It is seen as a danger. Why have something dangerous wandering around the island, a relatively small space? The status per the IUCN Red List of Threatened Species™ (Red List) as at 2009 for these subspecies of tiger is as follows:
It is expected that if the current decline in tiger populations continues it will become ecologically extinct in 20 years (no longer able to be the top predator)13.
I have already mentioned that three of the eight (possibly 9) subspecies are extinct. The South China tiger is almost certainly extinct in the wild. The Siberian tiger population is precarious especially in terms of breeding (the effective breeding population is the equivalent of 35 individuals it is thought6). Its habitat in Russia (90% are in Russia1) is cut into two by industrialisation and human activity (Siberian tiger habitat). This is habitat fragmentation and it undermines genetic diversity and therefore survivability. On the right is a chart7 8 on the Siberian tiger populations in Russia (as at 2007 there were 331-393 adult-subadult Amur tigers1) . This subspecies also occurs (or occured) in northeast China (and Korea?) but its primary or sole home is now Russia as none were recorded in 19877 in China. In 1998 a survey indicated that there were 4-6 tigers7 in China. The estimated number at 2007 (on a China government survey) was 18-221. What is the minimum viable population size? How does this impact inbreeding (new window)? And also please see: Inbreeding of Wildcats. Despite an increase in population over a long period it is still inordinately low. In addition to habitat loss the Siberian tiger has suffered from prey base loss, poaching and human/tiger conflict (see below for more on that). Bengal tiger In the early years the attitude towards the tiger was that it was a creature to be killed for sport or as a nuisance (see tiger hunt extract from 1815 below right). We have come to realise that the tiger is an asset to the world. The Bengal tiger lives largely on reserves in India and Bangladesh and is gradually losing the battle for survival in the wild, with a precarious population of about 1,400 - see Tiger Population in India. The threats to survival are what I would call the "usual suspects" all generated by human activity. Perhaps top of the list is poaching for body parts (penis is worth $6,00010) to supply Chinese pharmacies. This is compounded by inadequate policing of the reserves (unfair?). Are the reserves too small to sustain viable populations of tiger? Historically habitat loss and fragmentation has also been a major factor in population decline. This is stabilising as the tigers now live in reserves that should remain the same size (but it is said that 60+% of Bengal tigers live outside reserves7). Bengal tigers are still poisoned 
and I say corruption
and mismanagement
plays a role in the demise of the supposedly protected Bengal tiger.
Forcing tiger and human together results in injury and loss to both
parties and then some people start calling the tiger a man
eater.
People can kill a tiger
in self defence
but is the law sound (The Wildlife
Protection Act 1972)? The Sundarbans in Bangladesh is an area where a
high level of tiger
attacks
take place.
Sumatran tiger
Nowadays it is just killed as a result of neglect and apathy as its forest habitat is destroyed by Asia Pulp and Paper (APP) a large company with a dubious history (habitat loss is at 3.2-5.9% per year1). It is also poached despite being protected by the Indonesian government since 19727. But the government is killing this tiger by allowing the forest to be destroyed for paper. There was only 3% of forest left at 19897. See Sumatran tiger and Deforestation in Indonesia (new window). The reserves are too small for tigers7. The population is estimated at 441-679 (2009) and its habitat covers 51,944 km˛1. However, in terms of its breeding ability it behaves as if the population is 176 - 2711 (40% of the total actual population). Is this a viable number in the long term?
South China tiger The fact that this tiger is probably extinct almost makes a discussion about threats to survival pointless. If there are a very low number left the population is probably unviable anyway. China likes to turn tiger bone to wine etc. The tiger was considered a nuisance. Nowadays they have captive tigers aplenty in tiger farms ostensibly for conservation but it said that they are tiger body part factories10 and that they undermine conservation by muddying the picture. Indochinese tiger This tiger's status in terms of threats to survival is little known because "it status is poorly known" (in comparison to other tigers). There are no population estimates from Laos for example1. But suffice to say that the usual suspects apply such as habitat loss (Thailand's lowland forest has been susbtantially destroyed7) and fragmentation (low populations of tigers enclosed in isolated patches of remaining forest7), poaching for commercial sale of body parts, prey base loss and conflicts between humans and tiger. There were an estimated 250 tigers in Thailand at 1991 with an estimated 150 of those being breeding tigers7.
The status of the tiger is Asia is precarious and it is no different on the Malaysian peninsula. In the 1950s they were plentiful and treated as a nuisance. Being no more precious than a rat they were killed promptly. See the table right for some figures7. There appears to be some good news. The Malaysian government (at Nov. 2009) intends to better protect the tiger in their country and double numbers - let's see. Captive tigers Another grave situation is that even the captive tigers are endangered. There are 12,000 tigers in captivity and about 4,000 wild tigers. This is because they are inbreed. The Siberian and South China tiger come to mind but it applies to all captive tigers. This creates a cat with a weak constitution. And many of the tigers in captivity are simply not the species of tiger that it is stated to be. It will be a cross breed of some sort. That technically means the various subspecies of tiger in captivity have merged to a large extent. In order to prevent inbreeding it would seem outcrossing is necessary. This indicates that it is not viable to keep the tiger in captivity, doesn't it? As we are heading towards captive tigers as the only tiger remaining this is an unhappy state of affairs. I must also mention the tiger farms in China. There are 4,000+ tigers in tiger farms5. These are ostensibly for conservation but it is believed that they are more about creating a supply of tiger parts for popular tiger products. See tiger farms for more. Human Conflict with the tiger7 Tigers will kill any animal that is in a vulnerable position7. They kill animals much larger than themselves. And they sometimes kill people. The Bengal tiger of the Sundarbans (in Bangladesh) is where most people are attacked by tigers. My reading indicates that tigers do not treat humans as a first choice as prey, quite the contrary. Their attacks on people are usually the last resort of a starving, old or injured tiger (90% of the time because of injury to the tiger11). The same applies of course to all the large wildcats (see Man Eating Leopard ).
When you consider the
potential for tiger attacks the relative scarcity of them supports what
I have said. In fact tigers tend to avoid people. They would appear to
recognise that we are dangerous to them. Tigers are reluctant to attack
unless provoked (after a warning roar and rush from the tiger when for
instance protecting young or a kill).But the conflict between tiger and human is a crucial part of the threat/conservation process. Research has apparently not come up with a clean and readily understandable answer7. But in the Sundarbans an estimated 100-150 people are killed by tigers annually and the vast majority are fishermen (the Sundarbans is swampy delta region). As a tiger attack leads to killing the tiger, preventing attacks conserves the tiger. One clever method was to provide masks for people working in the area. The masks were a face made of rubber. It was worn on the back of the head. Tigers usually attack from behind. The mask meant that no one presented their back to the tiger and attacks declined dramatically. This was instigated in 1987. I don't know if it is still in force. The classic scenario of a man eater is that the tiger becomes injured. This may typically occur when a male is seeking a home range having left the natal area. The young tiger may come into conflict with a male with an established home range. A wound received in a fight can leave the tiger unable to kill wild prey so softer targets are sought such as livestock and people (who are likely to be around if the tiger is killing livestock). Other injuries can come from gunshots (this is an example of human indirectly killing another human if this forces the tiger to become a man-eater). Another example of people indirectly killing other people through the tiger is by habitat loss. Human activity erodes the habitat of tigers. Tigers like other wild cats need a home range, an area that is theirs. We see this in the domestic cat. Where competition for home ranges is fierce due to scarcity of space a male tiger may become "homeless" and wander. This forces them into "marginal areas" within their overall range and into contact with people and livestock where man-eating can begin. This would apply to healthy as well as injuried tigers. Interestingly, the humble porcupine may be responsible for creating some man-eating tigers. The quills can cause debilitating injuries.
Status in the Wild - ConservationUnder this heading, in respect of conservation it is appropriate to ball all the tiger subspecies together as on paper they all have the maximum protection that humankind can afford them. In practice the protection does not translate to anything like the kind of protection that is sufficient because populations continue to decline when all the subspecies are combined. Please note: all the wild cats listed on the wild cat species page contain fairly detailed information about conservation and threats. This page is more an overview.Conservation can be discussed under several headings:
The Red List is another worthy concept and organisation but for me they simply record the demise of the tiger. If a government wants to ignore the status of a species and the warning signs, it can and will and they seem to do just that. The Red List sometimes simply states that more research work is required as not enough is known (for example the Indochinese tiger in Laos). Then probably nothing happens. There are no international laws governing the protection of the tiger. I think there should be because the tiger today in particular belongs to the world and not to individual countries. Although organisations such as the World Bank work at an international level on tiger conservation. Save The Tiger Fund is also cross-governmental and has provided substantial funds. The Sunquists say that novel methods need to be implemented such as devising a way for tigers to live in the same areas as people rather than shunting them off into reserves. It is fair to say that reserves do not seem to be that successful. They are arguably poorly managed and sometimes too small it could be argued (see Indian Bengal Tiger Reserves). Although even small reserves can support a good tiger population provided the prey base is high. 58 principal prey can support 16.8 tigers per 100 km˛7. Small reserves of 300+ km˛ can support a tiger population that is viable it seems. Although there is conflicting information that says that all reserves are too small14. Camera trap technology has advanced and is a useful tool to assess population sizes even when the population densities are very low.
Tiger Description
The Sunquists say that the tiger is the only striped cat. They mean wild cat because the mackerel tabby (new window) and Togyer are stripped cats. Lots has been said about the weight of the tiger but reliable weights of wildcats are difficult to find7. What is certain is that the weights of the subspecies various and as you go south the weights are less as the chart above indicates. This is due to prey size. In Java a smallish deer (sambar deer - is this deer smaller on Java?) was the principle prey while Siberian tigers prey on larger animals such as the red deer and moose. The Indonesian tigers (Bali - extinct, Java - extinct and Sumatra) were or are darker too7. The fur is also understandably shorter and less dense as the climate is considerably warmer. Officially the tiger's background color is reddish orange to ocherous7 (the color of ocher; esp., dark yellow15). The underparts and inside of the limbs, throat, chest, muzzle and around and above the eyes are white creating a very high contrast coat. There is the usual white "ocelli" on the back of the ear flap. The tiger has the very recognisable dark vertical stripes on the flanks and shoulders. They vary in width and spacing and each, like a finger print is unique allowing researchers to identify individual tigers from photographic records (see Tiger Patterns and Tiger Stripes). The high contrast and colorful coat looks as if it is poor camouflage but in the dampled forest light it is perfect. There are meant to have been black tigers (melanistic tigers) and there are certainly white tigers (and see Snow tigers) and blue tigers. These colour variations are all due to genetic mutations and none are considered seperate species of tiger. There are three records of black tigers from the Mayanmar/NE India/Bangladesh area. There is no evidence in existence other than the recorded sighting. White tigers are common in captivity and either extremely rare or non-existent in the wild. They are inbred in captivity being the decendents of a single male Bengal tiger cub called Mohan captured in 1951 in Madhya Pradesh, India. The tiger is very powerful and built to capture and hold on to large prey. Their forelimbs are noticeably more powerful than the hind limbs. They are fine climbers and swimmers. The Siberian and Bengal stand about one metre tall at the shoulder. The tallest domestic cat, MAGIC, a F1 savannah cat is 17.1 inches tall at the shoulder. One meter is 33 inches. The tiger is taller at the shoulder than at the rear. They are similar in size to the lion but at the end of the day, I say the tiger would win in a Lion vs Tiger fight (which cannot take place as their ranges are very far apart). DistributionI have created several pages on the ranges of the tiger and indeed all the wildcats so I won't go into great detail here but refer to those pages. Suffice to say that the range of the tiger has been on a continual downward path for about a century and a crisis point has been reached it seems. The tiger can no longer be forced into small reserves without further decline in population size. The tiger range is now so fragmented it is almost impossible to draw it. The Caspian tiger was not a subspecies and is extinct while the South China tiger as mentioned is all but extinct living in China (Fujian, Guangdong, Hunan, Jiangxi). The distribution of the other tigers is as follows.
Ecology + Behavior + Social OrganisationOverview
One predator that the tiger avoids is the human, which means it has become nocturnal. Given a free choice the tiger would hunt day or night and kill any animal that is vulnerable to it. Often hunting means travelling great distances by human standards. For example, males not uncommonly travel 30 kms per night in search of food. The search for food starts at sunset. Tiger have well worn routines (don't domestic cats too) and will travel along the same routes to known hunting sites. A failure to catch prey means moving on as the tiger's presence is often by then well advertised by the alarm calls of the deer. Prey As mentioned tigers are adaptable and although there are favorite prey species they will eat almost anything up to an elephant. But other top predators are not commonly attacked as prey for obvious reasons. Deer and wild pigs are the most common prey. The type of deer depends on the region. Typical deer species would be Sambar and Chittal (see photo). This preference for pigs and deer extends from India (Bengal tiger) to Russia (Siberian tiger - in Russia up 84% of all tiger kills are pigs or red deer7). In the south, say in Thailand the prey is smaller such as barking deer. The tiger does not select weak and/or old prey. Prey that is substantially larger than the tiger is also killed, e.g. water buffalo and gaur. In timespast people, for entertainment, thrust buffalo and tiger together in a cage. The buffalo always won. So this is dangerous prey. Tigers are killed by buffalo and bison.
The tiger is a wrestler rather than a runner. This dictates its hunting style. Tiger won't run far (150 metres) but prefer a short burst high impact attack. Small animals are killed by a bite to the back of the neck severing the vetebra while larger prey is suffocated by biting the throat. The former method is employed by the domestic cat. Whiskers and teeth feel the spot on the spine of the prey to severe it. Prey is hauled to a safe spot under cover before feeding. The tiger's enormous strength comes into play here. There are some awesome stories. A tiger in Myanmar hauled a gaur weighing 770 kgs. Fourteen men couldn't move it7. Up to about 27 kgs of killed prey is eaten in a night7. Social Organisation Tigers like all cats are territorial. A dominant male's home range (the area that the tiger considers his area of operation) will overlap or encompass the usually exclusive (not overlapping) ranges of a number female tigers provided there is a sufficient density of females which is dependent on the prey base. While a less successful male tiger will be lucky to have one female. The male range is therefore much larger than that of the female tiger. Males will compete for a females particularly if the female density is low. Fights lead to injuries. Fights occur more frequently when there is social instability for any reason:
The Siberian tiger range is much larger due to a lower prey base, prey migration, climate and terrain. Tigers communicate vocally and through scent and marks (scrapes). Those of us who keep cats are all familiar with scent marks. Scent is sprayed onto objects. It is a musky liquid sometimes mixed with urine. Scent is also on feces from the anal glands. Rubbing objects with the head and cheeks also deposits scent on objects. Scrapes are made by scratching the ground. Feces are deposited. One advantage of communicating by scent is that the time the tiger was were the scent it can be gauged by the intensity of the scent. This helps avoid conflict. Scent markers are placed along important routes and boundaries of the home range of the tiger and reinforced regularly (every 3 weeks7). Scent marking is more intense when a young tiger is establishing a territory. Scent is not only used to avoid each other but to bring each other together for mating. The functions of scent marking are not fully understood by us and include much more than mentioned here due to space limitations and load times. Vocalisations are also used to communicate. We are familiar with the tiger roar. Sounds made close range are accompanied by body language. Other tiger sounds are, main call, prusten, growl, snarl, hiss, grunt, moan, meow, spit:
Tigers also communicate with their markings. For example the white spot on the back of the ear flap (ocelli) gives a signal to opponents to beware as it becomes visible from the front when the ears are flattened (to protect them) prior to a fight. Most domestic cats flatten the ears in the same way but have lost the spots. Wild cat hybrid domestic cats retain them. DevelopmentThe development of the tiger7 is about a timetable. Things happen at a certain time. Accordingly, I have set out this section in a table for ease of reference. Male tigers have a tough time of it. Where there is a good prey base the tigress is likely to be pregnant or have young to feed as is therefore unavailable. A tigress will scent mark to draw in a male tiger for mating. More than one can arrive resulting in potential conflict. During estrus the tigress will call more and roll and rub and behave provocatively and aggressively. She will spit at the male and strike him. The male is passive as his objective is to mate not fight. The tigress softens and lets the male advance. She kisses him with a gentle bite. After copulation during which the male bites the scruff of the female's neck to protect himself she boxes him but there is less aggression if she knows him. Tigers mate in a very similar way to the domestic cat. See Cats Mating and Lions Mating (new window).Cats are induced ovulators meaning ovulation occurs not to a timetable but on copulation. Before birth the mother finds a quite place such as a cave to have kittens. A tigress is under a lot of stress in terms of nutritional requirements during the time the cubs are suckling.
The period of dispersal for a male (when they become independent) is fraught with difficulty and danger. They can get into fights with resident males and be badly injured. Females not infrequently settle down into their own breeding territory near their mothers. See also Baby tigers. ConclusionBut for humankind the tiger would be the world's top predator. It combines great strength with limitless courage and agression when required. This is supported by a wide range of skills that always impress the rather feeble human. That is why we have to kill it. We fear the tiger. It fears us.From Tiger to Wild Cat Species Form
References/sources:1.The IUCN Red List of Threatened Species™ 2. SBI Brainstormer 3. Feline Conservation Federation magazine vol 53 issue 3 - Robert M Johnson 4. Creative Commons license: Attribution-Non-Commercial-No Derivative Works 2.0 Generic 5. WikipediaŽ 6. http://www.pictures-of-cats.org/siberian-tiger-habitat.html 7. Wild Cats Of The World - Sunquists - 2002 8. news.bbc.co.uk 9. Published under a Creative Commons license Attribution-Non-Commercial-No Derivative Works 2.0 Generic 10. PoC Blog 11. Corbett 12. tigersincrisis.com 13. Save The Tiger Fund - Setting Priorities For the Conservation and Recovery of Wild Tigers 2005-2015 14. Woodroffe and Ginsberg 1998 15. Your Dictionary 16. WWF |
