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Tiger - Panthera tigris
Topic Started: Jan 7 2012, 08:50 PM (34,935 Views)
Superpredator
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Some info about Tiger predation:
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Note that Gaur took up 9.3% of all prey killed in Kanha Park according to"The Deer and the Tiger: A Study of Wildlife in India", George Schaller. Also note that Sambar took 29.3% of all prey killed in Chitwan NP according to "The Face of the Tiger", Charles McDougal.

Source: "The Social Organization of Tigers (Panthera tigris) in Royal Chitawan National Park, Nepal", Melvin E. Sunquist.

Here is a link to "The Social Organization of Tigers (Panthera tigris) in Royal Chitawan National Park, Nepal".
Edited by Superpredator, Dec 3 2012, 07:14 PM.
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Some info about how Tigers bring prey down:
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From "Tiger predatory behaviour, ecology and conservation" by John Seidensticker and Charles McDougal.
Here is a link to "Tiger predatory behaviour, ecology and conservation" by John Seidensticker and Charles McDougal.
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Whilst only a small recovery, it's good it's actually happening!

Protected Tigers, Burning Bright
By RACHEL NUWER

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A tigress and her two cubs, via a camera trap in Thailand’s Huai Kha Khaeng Wildlife Sanctuary.

Tigers have delivered a bit of holiday cheer: populations are on the upswing, it turns out, in some protected areas in India and Thailand. In a field often dominated by news of felled forests and population declines, wildlife conservationists have taken heart from this development, while noting that tigers have a long, long way to go if they are to claw their way off the endangered species list.

“If the conditions are right, tiger populations can recover, though there’s still plenty of challenges,” said Cristián Samper, the president and chief executive of the Wildlife Conservation Society. “I think the encouraging news is that we now know it can work.”

At the start of the 20th century, tigers numbered around 100,000 and occupied forests from Turkey to Russia to Indonesia. Today around 3,200 wild tigers occupy just 6 percent of their historic range as a result of habitat destruction, retaliatory killings and poaching for the illegal wildlife trade. “We’ve reached a point where tigers are so much in danger of being lost that we suddenly value them and realize how important it is to hold on to them,” said John Robinson, the Wildlife Conservation Society’s chief conservation officer.

The Wildlife Conservation Society first homed in on the tiger problem in the 1960s, starting with India. Thanks in part to a strong commitment from the Indian government, tigers in the Western Ghats region of Karnataka State have quadrupled in number over the past 30 years, with 250 to 300 of the large cats currently living in the area.

The organization monitors the tigers with camera traps, using unique stripe patterns to identify individual animals and monitoring the abundance of tiger prey as well. (Prior to the advent of camera traps, researchers estimated tiger numbers by counting their tracks). The government provides support for keeping poachers at bay and managing conflicts with humans.

“The underlying factor in the few successes we’ve seen is when the government takes a real interest,” said Alan Rabinowitz, chief executive of the conservation organization Panthera, one of the Wildlife Conservation Society’s collaborative partners. “An N.G.O. along can’t accomplish this alone — the government really has to step up and put in its own law enforcement resources.”

With lessons from the Western Ghats in hand, the conservation organization began expanding its tiger program to include India’s Bhadra and Kudremukh tiger reserves, which have since seen around 50 percent increases in tiger populations. Conservationists also set up shop in Thailand’s Huai Kha Kaeng wildlife sanctuary, where tiger poaching had reached epidemic proportions as a result of black market demand for the animals’ bones, reproductive organs, pelts and meat.

The Thai government bolstered enforcement and anti-poaching patrols as the scientists outfitted the area with camera traps. Last February, those traps proved useful not just for monitoring tiger populations but also for providing evidence in court that tiger poachers took their illegal prey from the sanctuary. Today, around 50 tigers roam that forest.

But not all tigers can be saved. In Vietnam and Cambodia, for example, conservationists have largely written tigers off as a lost cause; tiger numbers in Myanmar and Laos are steadily decreasing.

Rather than trying to protect every remaining individual tiger from the varied problems that threaten to wipe out the species, the Wildlife Conservation Society decided to focus on so-called “source sites,” or areas where at least 25 breeding females live. So far, the organization has identified 42 such sites in India, Laos, Myanmar, Thailand, Russia and northern China, and it is working in 24 of them. “These are areas where we have a realistic chance of protecting tigers,” Dr. Robinson said. “This enables us to focus our attention.”

To undertake protective measures in all 42 sites would require an investment of around $95 million annually. Half of that money is in place as a result of governmental support and fund-raising by nongovernmental organizations, but funds are lacking for further expansion. “Basically, we need to ramp up our financial support for law enforcement, tiger monitoring and addressing wildlife trade issues within countries,” Dr. Robinson said. “If we could put those pieces in place, we could turn things around for tigers.”

For now, however, conservationists are celebrating the small victories.

“Things are not good in the tiger world, but they’re better than they were,” Dr. Rabinowitz said. “Some tigers are going to blink out, but there’s still a lot of hope for saving them in some really wild areas.”

An earlier version of this post misstated the number of tigers thought to dwell in the Western Ghats region of Karnataka State in India. It is 250 to 300, not 600. The post also misidentified the sites where the Wildlife Conservation Society more recently began introducing its tiger program. They are the Bhadra and Kudremukh tiger reserves, not the Nagarahole and Bandipur national parks, where the conservation program started earlier.


http://green.blogs.nytimes.com/2012/12/24/scattered-tiger-populations-burning-bright/
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Tigers Making a Comeback in Parts of Asia
Strong government actions helping the big cat, scientists say.


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The Indochinese tiger (pictured) is a subspecies growing in number.

Ker Than
for National Geographic News
Published December 28, 2012

Tigers are making a comeback, thanks to strong government initiatives in India, Thailand, and Russia, scientists announced this week.

Joe Walston, executive director for Asia Programs at the Wildlife Conservation Society (WCS), praised the three countries for taking action to protect their tiger populations. The animals are endangered globally.

There are six remaining subspecies of tiger that live in 13 Asian countries—a habitat that's reduced by 93 percent from their historic range.

"There are a number of factors that are necessary for tigers to come back, but without true government commitment, there will not be any success," Walston said.

Taking Steps to Save Tigers

In India's Nagarahole and Bandipur National Parks, for example, a combination of strict antipoaching patrols, surveillance, voluntary relocation of people away from tiger habitats, and scientific monitoring have helped the big cats rebound to the point where they have saturated the two national parks.

This success is only possible because the Indian state of Karnataka is dedicated to conserving tigers, Walston said.

In Russia, government officials are drafting a new law that makes the transport, sale, and possession of endangered animals a criminal offense rather than just a civil crime. This closes a loophole that currently allows poachers to claim they found endangered species like tigers already dead.

Russia also recently announced that it was creating a new corridor for safe tiger passage called the Central Ussuri Wildlife Refuge, which would link tiger breeding strongholds in Russia and China.

Corridors "allow tigers to move between different areas to breed and connect up," Walston explained. "This makes for larger, more robust, and genetically healthy populations."

In Thailand, enforcement and antipoaching patrols have been beefed up in the Huai Kha Khaeng Wildlife Sanctuary. In 2011 the government busted a notorious poaching ring, and this year the gang leaders were given prison sentences of up to five years—the most severe prison sentences for wildlife poaching in Thailand's history. Since the gang's capture, there have been no known tiger or elephant poaching incidents in the park.

What's more, "Thailand last year had a poaching problem, and instead of ignoring it, the government recognized the problem and hired 60 new rangers," Walston said.

Tigers Can Bounce Back

But these three success stories are rare bright spots for the endangered species, whose numbers continue to hover at all-time lows worldwide due to the combined threats of poaching, loss of prey, and habitat destruction.

Conservationists estimate that only 3,200 tigers exist in the wild.

Even so, Walston said the successes in India, Thailand, and Russia prove that tigers are not doomed—and he hopes other countries will take notice.

"This is not a species that is on an inevitable decline ... They are coming back in some places," he said.

Walston also pointed out that saving tigers has other benefits.

"When we conserve tigers, we're actually conserving a whole host of species that are maybe not as charismatic or iconic but are equally valuable—and equally threatened," he said.

http://news.nationalgeographic.com/news/2012/12/121228-tigers-big-cats-animals-science-conservation-asia/
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Panthera tigris soloensis
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Russia leopard mission collars massive tiger
An extremely rare Amur tiger captured in a remote area of Russia by an international research team searching for the even rarer Amur leopard has boosted the chances of saving both species from extinction.

Capture and examination of the huge male tiger was a major success, said big cat specialist vet Dr John Lewis, WVI co-founder and director and on the team in far eastern Russia in autumn 2011. He explained: “We need to catch, assess and radio collar tigers as well as leopards if we are to discover how they co-exist.

“Tigers are present in the proposed leopard reintroduction area and we must know the risks for any leopards released there. Infectious diseases affecting tigers can equally affect leopards so health screening has major conservation relevance for both animals.” (See Our Project)

His work on the Amur leopard – the world’s most endangered big cat with as few as 25 left in the wild – positions WVI as the key veterinary support in the programme to save it from extinction in the wild.

Text messages, from an area notorious for poor communications, illustrate the tiger capture build-up: “Fresh tiger prints 1km from camp this morning! Think we are getting closer”, followed by a triumphant; “Caught large male tiger!”

The tiger, one of just 450 remaining, was anesthetised for examination and released with a GPS tracking collar. It is the only traceable individual in the area, he believes, after signals from previously collared tigers have been lost.

Leopards were heard close to camp and traces found on aptly-named Leopard Ridge, but none captured. Two large black Asiatic bear were also been captured and data logged.

The team, including young Russian field vet Dr. Mr Mikhail Gonchuruk, spent two months tracking the elusive, solitary and nocturnal Amur leopard before temperatures plummeted below -20 degrees centigrade, inhibiting their sensitive immobilising leg snares.



WVI needs to raise £25K a year to continue its Amur leopard project support – likely to increase as the breeding and release phases get closer. Donate now.

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One can view these photos directly from the source by clicking on the image of the tiger in the article.

Article:
http://wvi.whimwhamsites.co.uk/russia-leopard-mission-collars-massive-tiger/
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He has massive head,paws & it's amazing they he is barely going into his prime!

More pics:

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Thanks for this, I can only imagine how big he is at this time!

Hopefully he spreads his genes & has many cubs!
Edited by 221Extra, Jan 4 2013, 08:56 AM.
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Taipan
Dec 29 2012, 01:42 PM
Tigers Making a Comeback in Parts of Asia
Strong government actions helping the big cat, scientists say.


Posted Image
The Indochinese tiger (pictured) is a subspecies growing in number.

Ker Than
for National Geographic News
Published December 28, 2012

Tigers are making a comeback, thanks to strong government initiatives in India, Thailand, and Russia, scientists announced this week.

Joe Walston, executive director for Asia Programs at the Wildlife Conservation Society (WCS), praised the three countries for taking action to protect their tiger populations. The animals are endangered globally.

There are six remaining subspecies of tiger that live in 13 Asian countries—a habitat that's reduced by 93 percent from their historic range.

"There are a number of factors that are necessary for tigers to come back, but without true government commitment, there will not be any success," Walston said.

Taking Steps to Save Tigers

In India's Nagarahole and Bandipur National Parks, for example, a combination of strict antipoaching patrols, surveillance, voluntary relocation of people away from tiger habitats, and scientific monitoring have helped the big cats rebound to the point where they have saturated the two national parks.

This success is only possible because the Indian state of Karnataka is dedicated to conserving tigers, Walston said.

In Russia, government officials are drafting a new law that makes the transport, sale, and possession of endangered animals a criminal offense rather than just a civil crime. This closes a loophole that currently allows poachers to claim they found endangered species like tigers already dead.

Russia also recently announced that it was creating a new corridor for safe tiger passage called the Central Ussuri Wildlife Refuge, which would link tiger breeding strongholds in Russia and China.

Corridors "allow tigers to move between different areas to breed and connect up," Walston explained. "This makes for larger, more robust, and genetically healthy populations."

In Thailand, enforcement and antipoaching patrols have been beefed up in the Huai Kha Khaeng Wildlife Sanctuary. In 2011 the government busted a notorious poaching ring, and this year the gang leaders were given prison sentences of up to five years—the most severe prison sentences for wildlife poaching in Thailand's history. Since the gang's capture, there have been no known tiger or elephant poaching incidents in the park.

What's more, "Thailand last year had a poaching problem, and instead of ignoring it, the government recognized the problem and hired 60 new rangers," Walston said.

Tigers Can Bounce Back

But these three success stories are rare bright spots for the endangered species, whose numbers continue to hover at all-time lows worldwide due to the combined threats of poaching, loss of prey, and habitat destruction.

Conservationists estimate that only 3,200 tigers exist in the wild.

Even so, Walston said the successes in India, Thailand, and Russia prove that tigers are not doomed—and he hopes other countries will take notice.

"This is not a species that is on an inevitable decline ... They are coming back in some places," he said.

Walston also pointed out that saving tigers has other benefits.

"When we conserve tigers, we're actually conserving a whole host of species that are maybe not as charismatic or iconic but are equally valuable—and equally threatened," he said.

http://news.nationalgeographic.com/news/2012/12/121228-tigers-big-cats-animals-science-conservation-asia/
This is great news! Hopefully, tigers' conservation status will once again be on Least Concern.
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Siberian Tiger Predation Study

Source: Specific Features of Feeding of the Amur Tiger Panthera tigris
altaica (Carnivora, Felidae) in a Densely Populated Locality
(with Reference to Bol’shekhekhtsirskii Reserve and Its Environs), ISSN 10623590, Biology Bulletin, 2012, Vol. 39, No. 3, pp. 279–287. © Pleiades Publishing, Inc., 2012. Original Russian Text © K.N. Tkachenko, 2012, published in Izvestiya Akademii Nauk, Seriya Biologicheskaya, 2012, No. 3, pp. 336–345.


Predation on Wild Boar and Red Deer ("Manchurian Wapiti") - Wild Boar Preferred

Of wild animals, Manchurian wapiti and boar occupied a considerable proportion in the food spectrum of tigers at Khekhtsir. As a whole, attacks on Manchurian wapiti were recorded more (n = 13) than on the boar (n = 7). Manchurian wapiti in the reserve is more numerous, and, correspondingly, the number of encounters with it is greater than even in search for boar, on which the hunter selectivity of the tiger is directed (Table 2). The proportion of boar hunts is by a factor of 1.9 higher than its relative abundance in nature; and that of Manchurian wapiti, by a factor of 1.01, which indicates a weaker hunting specialization. It is easier for the tiger to take boar (especially young individuals yearlings and twoyear olds) than Manchurian wapiti, which is one of the causes of the purposeful pressure on it on behalf of this predator (Yudakov and Nikolaev, 1987; Yudin and Yudina, 2009; author’s unpublished data). For instance, of 13 tracedManchurian wapiti hunts, four appeared to be successful (30.8%), of six boar hunts (one attack of Tridactyl on a oneyearold boar whose results remained unclear was not considered), three were successful (50%).

The pattern of relations between the tiger and hoofed animals is dynamic and can change in different years, for instance, depending on the numbers of boar. The most demonstrative in this respect are two winter seasons. For instance, in winter of 1995/1996 in the period of low numbers of boar, the frequency of occurrence of its remains in tiger’s excreta (n = 27) was 6.9% and that of Manchurian wapiti, 48.3%. In winter of 1999/2000 at a considerable increase in the amount of boar, the proportion of its remains in the tigers’ excreta (n = 20) was 75% and that of Manchurian wapiti was 5%. A similar ratio was recorded also in the Ussuri Reserve (Litvinov, 2007).

Feeding of males and Tridactyl female differed insignificantly in the main species of prey (boar, Manchurian wapiti). For instance, in the diet of male A, Manchurian wapiti dominated slightly, 59.5% (according to analysis of excreta, n = 42), the occurrence of boar was 40.5%. In the food spectrum of the tigress (n = 30), boar occupied 60%, and Manchurian wapiti was slightly inferior, 40%. More distinct differences are found in the size of animals attacked by tigers. Males, in contrast to females, more frequently attack adult bigger individuals. Material on the size
and age of animals hunted by tigers is small, but it gives an idea of their differences in the males and the females. Among hunt objects of males (n = 5), adult animals (two males of Manchurian wapiti and two males of boar) are recorded more frequently and young animals (one boar), less frequently. Tridactyl (n = 4) attacked mainly young (three boars) and to a smaller degree adult animals (one female of Manchu-
rian wapiti). Thus, among prey of tigresses, smalleranimals dominate (Yudakov, 1973; Pikunov, 1981; author’s unpublished data).

Predation on Himilayan Black Bears - All Ages Killed and Make Significant Portion of Diet

Himalayan black bears (individuals of any age and sex) were more frequently attacked by tigers (Tkachenko, 2008). Two Himalayan bears—tiger’s prey—found in the reserve appeared to be adult (one of them male, the other, presumably, female). Claws of adult bears were also found repeatedly in the excreta of tigers. According to observations in Bol’shekhekhtsirskii Reserve, the tiger successfully hunted the Hima-
layan black bear at any time of the year. The greatest amount of found remains of the Himalayan black bear in tigers’ excreta collected in the cold time of the year was recorded in winter of 1995/1996 in the period of low numbers of the boar (in 27 samples in 41.4% of cases). In this winter season no Himalayan black bears crushed by tigers were found; however, according to freshness, sites, and time of findings of excreta of tigers with their remains, one can suggest that they crushed not less than three individuals, which at numbers of 30–35 head comprises 8.6–10% of the population. The importance of bears noticeably declined in winter of 1999/2000 at an appreciable increase in the boar amount and comprised 20% of findings in coprolites (n = 20), of them of Himalayan black bear comprised 15% (remains of other findings were not determined to species). Thus, the opinion is confirmed that the importance of bears in tigers’ diet increases with a general decrease in the numbers of hoofed animals (Bromlei, 1965). The suggestion that the tigers attack bears only when there is an insufficient amount of its usual
food—boar and Manchurian wapiti—(Rukovskii, 1968) is not quite correct since attacks take place also at their high numbers (Gorokhov, 1973; author’s unpublished data). Male tiger A specialized on hunting Himalayan black bear. The remains of two bears of this species found by us are its prey. In excreta (n = 56) of this individual collected from 1992 to 2000, bear remains comprised 31.6%, in particular, that of the Himalayan black bear, 22.8%; that of brown bear, 7%; and that of bear not determined up to species, 1.7%. In excreta (n = 15) of the tigress for the same period, bear remains were found in 20% of the samples. In published sources there is an indication made on the basis of studies by the method of radiotelemetry that in Sikhote Alin Reserve bears were killed only by male tigers, and that no significant cases of their take by
tigresses were recorded (Seredkin et al., 2005). Nevertheless, females are capable of killing a bear (Kaplanov, 1948), however, they do it more seldom than males. In January 2000, Tridactyl caught up with male A according to its track at the right bank of the Geologovskii stream, where it stayed for a while near the Himalayan black bear (presumably female) killed by it that they ate together. Bear remains were at a distance of 200, 120, and 80 m from each other, which is atypical of the tiger. From the food site, the tigers went away together, and it was seen from the tracks that rut began in them. The height of the snow cover in the hunt area was 30–35 cm.

From November to March, the occurrence of the Himalayan black bear in the feeding of tiger was 22.7% and from April to October, slightly lower, 16.7%. Brown bear, on the contrary, in the cold time of the year was recorded much more rarely (2.7%) than in the warm time (16.7%). Possibly, under conditions of the reserve, the Himalayan black bear in winter is more accessible to tigers since 50% of its dens (n = 14) were
in hollows, the entrance to which was at a height of one meter above the ground, in radical hollows, and on the ground. In other areas of the south of the Far East similar dens were found far more rarely (Sysoev, 1960; Pikunov, 1991). The main part of forests of Bol’shoi Khekhtsir (exception is made by fur–spruce forests of the upper part of the ridge slopes) is strongly disturbed by felling and fires. Bears lacking big trees
where an access hole could be located at a sufficiently great height, i.e., from two meters and higher, which greatly decreases their accessibility; therefore, they often have to arrange dens at sites where they are vulnerable to the tiger. In the warm period of the year the
Himalayan black bear is saved by its capacity for rapidly climbing trees, by which presumably one can explain its lower occurrence in the feeding of tiger at this time. Brown bear dens are in the upper part of the slopes where the tiger very seldom comes, which makes this species inaccessible. In the warm time of the year, the accessibility of the brown bear (especially of young individuals), unlike the Himalayan black
bear, increases considerably.

A drastic decline in the number of bears in the feed ing of tigers at Khekhtsir after the death of male A indicates the individual specialization of this individual in their hunt. Rutkovskii (1968), based on questionnaire evidence, also emphasizes that in Primorye
the tiger more frequently attacks the Himalayan black bear. In Lazovskii Reserve in the feeding of the tiger, only Himalayan black bear was recorded (Zhivotchenko, 1981; Khramtsov, 1993). According to other studies performed in middle Sikhote Alin, it attacks this species more seldom than the brown bear (Bromlei, 1965; Kostoglod, 1977; Seredkin et al., 2005). Apparently, such a contradiction is explained by the
difference of individual ecological conditions in areas where studies were performed. However, the fact that the Himalayan black bear of any sex and age is a typical prey of the tiger is obvious (Sysoev, 1960, 1966; Gorokhov, 1973; Kostoglod, 1977, 1981; Khramtsov,1993; Seredkin et al., 2005; Yudin and Yudina, 2009; author’s unpublished data). Despite active pursuit on the part of tigers, Himalayan bears at Khekhtsir were usually not afraid of fresh tracks, went along their paths, ate up the remains of their prey, and only in one case did a bear of this species run away after getting on the fresh scent of a tigress and two cubs (Tkachenko,
1996, 2004).


Brown Bears Preyed On Generally Are females and Young - Bears Killing Tigers from Other Studies Cited


The relationships of the tiger and brown bear have another pattern. Females and young individuals of brown bear become tiger’s prey more frequently (Seredkin et al., 2005). Obviously, at Khekhtsir the tiger more frequently attacked females and young individuals. A bear is also capable of being the first to attack the tiger and pursue it to get prey (Sysoev, 1960, 1966; Kostoglod, 1981). Over the territory of Kha-
barovsk krai and Primorye, remains of tigers killed and eaten by brown bears were repeatedly found (Sysoev, 1960, 1966; Rakov, 1965, 1970; Gorokhov, 1973; Kostoglod, 1977, 1981)

Tigers with Broken Fangs Shift to Dogs and Choose Smaller Dogs Over Larger Dogs When Condition Deteroriates

As was stated above, in the feeding of the Tridactylened individuals can specialize on their catch (Tkachenko, 2003). Yudin and Yudina (2009) based on their own observations and analysis of circumstances of death from tigers of gun dogs in the taiga and at populated sites also reached the conclusion that a dog is an unattractive, but very easy prey for it.

The loss of fangs does not immediately lead to the inability to get natural food. For instance, male tiger A before its appearance on the outskirts of a populated site existed for a long time at the expense of wild animals, despite broken off fangs, since by this moment
they had already become polished (Fig. 3). Possibly, a tiger that has injured its fangs is capable of dwelling in nature for years without coming into conflict with humans if it did not receive other serious injuries. However, the efficiency of its hunts drastically declines. As a rule, the prey is killed instantly (Yudin and Yudina, 2009), but a tiger with broken off fangs has to struggle with prey for a long time, and possibly, hoofed animals may manage frequently to tear themselves away. For instance, over the entire winter period of 2000/2001 in January a single prolonged scramble of the Tridactyl tigress with a very big and aggressive dog was recorded before it managed to kill it. From
February 2005 the number of similar scrambles with even smaller dogs that Tridactyl failed to kill instantly increased (Table 3). The success of hunting them also decreased from 95% (n = 20) at the end of 2000 and the first half of 2001 to 61.1% (n = 18) from 2005 to
2007. Moreover, it began to more frequently take dogs of middle size. If at the end of 2000 and the first half of 2001, dogs of middle size among its prey comprised 33.3%, of big, 55.6%, and of small, 11.1% (n = 9), from 2005 to 2007, the dogs of middle size accounted
for 70%, and big dogs, 30% (n = 10). Thus, a tiger with injured teeth weakens more rapidly than a tiger with normal teeth, which leads to the inability to provide tigress considerable changes occurred over 15 years. In the period of 1992–2000, the frequency of occurrence of remains of wild animals in excreta of the tigress (n =15) was 100%, and that of domestic animals, 0%. Only in December 1994 was an attack by Tridactyl on a dog in a forest near a state farm recorded; in this case the tigress ate up only one side (Tkachenko, 1996). From December 2000 to 2007 in its excreta (n = 50), the frequency of occurrence of remains of wild animals declined (44%) and that of domestic animals (dogs)
increased (56%). At this time we recorded attacks on dogs (30 individuals killed) only on the outskirts of populated sites, in the overwhelming majority of cases near houses or household buildings. From the second half of 2001 to January 2005 inclusively and from April
2005 to July 2006, no attacks on dogs at the outskirts of populated sites were recorded, but in the excreta of the tigress their remains were occasionally found. The transition to feeding on dogs occurred drastically (according to unofficial data the tigress was wounded in December 2000) (Tkachenko, 2009). Apparently, fangs were also broken off, possibly as a result of getting into a steel trap, which also promoted the transi tion to feeding mainly on dogs. This is supported by the absence of openings from fangs in the prey of the tigress at spots of seizing the prey by the throat. In a small dog (with the size of a fox) an opening on the head with about 5 mm in diameter was recorded when
the neck was seized from the top. A similar wound on the top of the head was present also in the Himalayan black bear killed by the male tiger A in January 2000 (this case was described above) prior to 1.5 months before its death. In the bear, bones of the cerebral chamber (Fig. 2) appeared to be broken through by “hemps” from the upper fangs of the tiger whose height turned out to be 1 and 1.3 cm (the height of the
lower fangs was 1.8 cm, each) (Fig. 3). In animals killed by tigers with normal teeth, openings from fangs remain on the neck (Matyushkin, 1991; Yudin and Yudina, 2009; author’s unpublished data). The accessibility of dogs in the environs of Bol’shekhekhtsirskii Reserve is very high; nevertheless, healthy tigers did not approach populated sites and showed no interest in dogs. Similar behavior is typical of tigers inhabiting remote districts of Sikhote Alin far from populated sites (Yudakov and Nikolaev, 1987). Dogs are not an attractive food for tigers, and only physically weak itself with natural food. This results in coming to populated sites in the search for easy prey.
Edited by Red Dog, Feb 15 2013, 04:31 AM.
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White Tiger Mystery Solved: Coat Color Produced by Single Change in Pigment Gene

May 23, 2013 — White tigers today are only seen in zoos, but they belong in nature, say researchers reporting new evidence about what makes those tigers white. Their spectacular white coats are produced by a single change in a known pigment gene, according to the study, appearing on May 23 in Current Biology, a Cell Press publication.
"The white tiger represents part of the natural genetic diversity of the tiger that is worth conserving, but is now seen only in captivity," says Shu-Jin Luo of China's Peking University.
Luo, Xiao Xu, Ruiqiang Li, and their colleagues advocate a proper captive management program to maintain a healthy Bengal tiger population including both white and orange tigers. They say it might even be worth considering the reintroduction of white tigers into their wild habitat.
The researchers mapped the genomes of a family of 16 tigers living in Chimelong Safari Park, including both white and orange individuals. They then sequenced the whole genomes of each of the three parents in the family.
Those genetic analyses led them to a pigment gene, called SLC45A2, which had already been associated with light coloration in modern Europeans and in other animals, including horses, chickens, and fish. The variant found in the white tiger primarily inhibits the synthesis of red and yellow pigments but has little to no effect on black, which explains why white tigers still show characteristic dark stripes.
Historical records of white tigers on the Indian subcontinent date back to the 1500s, Luo notes, but the last known free-ranging white tiger was shot in 1958. That many white tigers were hunted as mature adults suggests that they were fit to live in the wild. It's worth considering that tigers' chief prey species, such as deer, are likely colorblind.
Captive white tigers sometimes do show abnormalities, such as crossed eyes, but Luo says any frailties are likely the responsibility of humans, who have inbred the rare tigers in captivity. With the causal gene identified, the researchers ultimately hope to explore the evolutionary forces that have maintained tigers in both orange and white varieties.

Posted Image
These are white tigers at Chimelong Safari Park in China. (Credit: Chimelong Safari Park)

http://www.sciencedaily.com/releases/2013/05/130523143342.htm




Journal Reference:
Xiao Xu, Gui-Xin Dong, Xue-Song Hu, Lin Miao, Xue-Li Zhang, De-Lu Zhang, Han-Dong Yang, Tian-You Zhang, Zheng-Ting Zou, Ting-Ting Zhang, Yan Zhuang, Jong Bhak, Yun Sung Cho, Wen-Tao Dai, Tai-Jiao Jiang, Can Xie, Ruiqiang Li, Shu-Jin Luo. The Genetic Basis of White Tigers. Current Biology, 2013; DOI: 10.1016/j.cub.2013.04.054

Abstract
The white tiger, an elusive Bengal tiger (Panthera tigris tigris) variant with white fur and dark stripes, has fascinated humans for centuries ever since its discovery in the jungles of India [1]. Many white tigers in captivity are inbred in order to maintain this autosomal recessive trait [2,3,4,5] and consequently suffer some health problems, leading to the controversial speculation that the white tiger mutation is perhaps a genetic defect [6]. However, the genetic basis of this phenotype remains unknown. Here, we conducted genome-wide association mapping with restriction-site-associated DNA sequencing (RAD-seq) in a pedigree of 16 captive tigers segregating at the putative white locus, followed by whole-genome sequencing (WGS) of the three parents. Validation in 130 unrelated tigers identified the causative mutation to be an amino acid change (A477V) in the transporter protein SLC45A2. Three-dimensional homology modeling suggests that the substitution may partially block the transporter channel cavity and thus affect melanogenesis. We demonstrate the feasibility of combining RAD-seq and WGS to rapidly map exotic variants in nonmodel organisms. Our results identify the basis of the longstanding white tiger mystery as the same gene underlying color variation in human, horse, and chicken and highlight its significance as part of the species’ natural polymorphism that is viable in the wild.
http://www.cell.com/current-biology/abstract/S0960-9822(13)00495-8
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Scalesofanubis
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How a Dog Virus Could Wipe Out Tigers
June 11, 2013 10:20 am

Posted Image

You might not see so much of a similarity between your dog and a majestic tiger (and if you do, you’re probably just kidding yourself) but the two animals do share one important threat: distemper virus. Canine distemper virus (CDV) is incurable and causes high fever, watery eyes, lethargy, vomiting and diarrhea, progressing to seizures, paralysis and death. For a long time, CDV was limited to canines, but in recent years it has jumped from dogs to other pets and even wildlife. Today, CDV can infect ferrets, foxes, raccoons and even tigers. Some think that the virus contributed to the decline and extinction of the thylacine (also known as the Tasmanian wolf). In the 1990s, 30 percent of the lions who died in the Serengeti had succumbed to CDV. And in the past few years, it seems like the disease has jumped to tigers.
Reports of tigers behaving strangely was the first tip off, but a diagnosis of CDV requires brain tissue for analysis. In 2011, a confused and tired Amur tiger wandered into a town in Russia and had to be put down. She was the fourth radio-collared Siberian tiger in less than a year to be found confused, wandering into towns and villages, displaying strange behavior. An analysis of her brain tissue confirmed everyone’s fears: CDV had left her too weak to hunt, disoriented and willing to risk a human village to look for food.
“Since 2000, in the Russian Far East, there have been a few cats reported as behaving strangely and coming into villages, apparently not showing much fear towards people,” John Lewis, the director of Wildlife Vets International, told the BBC. “In the past few years, tissue from at least a couple of those cats have now been confirmed as showing the presence of CDV infection.” These tigers are probably getting CDV directly from dogs, as tigers often will prey on the canines that stray too far from villages. And Lewis says it’s not just death from CDV that they’re worried about. Tigers infected with CDV show strange behaviors, like losing their fear of people. This puts them at greater risk of hunting from poachers and being hit by cars on roadways. And there’s not a ton people can do to stop it, says John Platt of Scientific American:

Now that canine distemper has been identified, the next step, according to WCS Chief Pathologist Denise McAloose, is to identify the source of the infection, which could be coming from domesticated dogs or other local carnivores such as wolves, badgers, red foxes or raccoon dogs. “From a vaccination perspective, vaccinating dogs would be a good first step,” she says. “If this were to be a recommended strategy, decisions about the safest vaccine for dogs and tigers that might eat the dogs would need to be made.” Distemper vaccinations are required for most pet dogs in the U.S., but not in Russia.

But even before that, Lewis says, researchers need to understand how to figure out the scale of the problem. He’s bringing together vets from all over the world who deal with tigers to try and nail down a strategy for understanding just how bad CDV is, what tests need to be done, and how. “We need to work out where we can send these samples for laboratory testing. We need to work out how we are going to store and move these samples. Once we have got that nailed down then we start work and try to design some sort of mitigation strategy, and that won’t be easy.” The question is whether or not the scientists can keep up with the virus before it’s too late.

http://blogs.smithsonianmag.com/smartnews/2013/06/how-a-dog-virus-could-wipe-out-tigers/
Edited by Scalesofanubis, Jun 12 2013, 05:00 AM.
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Taipan
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Dog Disease Infecting Tigers, Making Them Fearless
The big cat is catching canine distemper from domestic dogs, experts say.


Posted Image
A healthy Sumatran tiger pauses in the forests of northern Sumatra, Indonesia.

Photograph by Steve Winter, National Geographic
Christine Dell'Amore
National Geographic News
Published June 12, 2013

Cats and dogs don't usually mix. But a domestic dog virus is posing a new threat to endangered tigers in the wild, experts say—partly by making them less fearful of people.

Forced into increasingly smaller habitats, tigers are sharing more space with villagers and their dogs, many of which carry canine distemper virus (CDV), an aggressive, sometimes fatal disease that is usually found in dogs but is also carried by other small mammals.

The virus has infected 15 percent of the 400-some Siberian tigers in the Russian Far East, and has killed at least three, according to Wildlife Vets International (WVI), a U.K.-based conservation organization.

Based on odd tiger behavior on the Indonesian island of Sumatra, scientists suspect the virus is a problem there and in other countries. Many of these potentially CDV-infected tigers seem to be unfazed by people, wandering onto roads and into villages.

John Goodrich, now senior tiger program director of the conservation group Panthera, found the first known tiger with distemper in 2003 in Pokrovka, Russia: "This tiger just walked into a town and sat down. She was absolutely beautiful—a healthy-looking young tigress."

Even so, she had a fixed stare and did not respond to stimuli. "The lights were on, but no one was home," said Goodrich, who was then with the Wildlife Conservation Society.

Goodrich and colleagues anesthetized the tigress and found her positive for distemper. They cared for her in captivity for six weeks before she died.

Such fearless behavior is likely a symptom of brain damage caused by distemper, which also causes respiratory disease, diarrhea, seizures, loss of motor control, and sometimes death.

Veterinarians still don't know much about tiger distemper. It seems that the tigers "can get a mild infection that doesn't cause any problem—conversely it can be more serious than it is in the natural host," said Andrew Greenwood, a zoo and wildlife veterinarian at WVI.

Concerned by the development, WVI plans to work with the Indonesian government and veterinarians to launch the world's first tiger-disease surveillance program, which aims to find out how tigers catch distemper, identify the likely source of the virus, and determine how to best tackle it.

"If we get it right, it could help us forestall a major problem, which is the last thing tigers need in their precarious state," WVI director John Lewis said in a statement.

Conservationists estimate that only 3,200 tigers exist in the wild in 13 Asian countries—a 93 percent reduction of their historic range.

Deadly Distemper

Scientists first realized that canine distemper virus can cross over to felines when it broke out in captive big cats living in California in the 1980s, Greenwood said.

In recent decades, lions in the Serengeti have caught the virus from domestic dogs that live with Maasai herders, and a 1994 outbreak wiped out a third of the Serengeti's lion population.

Luckily, because tigers aren't as social as other big cats, the animals don't seem to be spreading distemper—an airborne virus—among themselves. It's likely that the tigers are eating dogs infected with the virus. An outbreak akin to what happened in 1994 in the Serengeti would be "catastrophic" for tigers as a species, Greenwood said.

Brain-damaged tigers who don't die from distemper and approach human settlements can be easily killed by poachers or by villagers concerned for their safety, he said.

To prevent tigers from getting killed, in addition to the surveillance program, WVI plans to create a rabies and distemper vaccine campaign in Indonesia, which would encourage people to vaccinate their dogs against the deadly viruses, Greenwood said.

Such a campaign was successful in Zimbabwe—where domestic dogs were sickening the rare African wild dog—when people realized that vaccinating their dogs would also help protect their children against disease.

Additionally, a vaccination program among the Maasai herders after 1994 likely prevented another outbreak of distemper in the Serengeti lions.

Last Straw?

Barney Long, head of Asian species conservation at WWF-US, said by email that "the threat of the distemper virus in tigers is real, and we should monitor it closely.

"I am glad a veterinary organization has done the research, so the correct expertise is on the case," he said.

"However, poaching remains ... the most immediate threat to tigers in the wild. Every part of the tiger—from whisker to tail—is traded in illegal wildlife markets."

Panthera's Goodrich added that distemper in tigers is a "definite concern," but it's not as worrisome as it is for lions.

Overall, disease is a conservation issue "that tends to get forgotten," WVI's Greenwood emphasized.

In some cases, isolated populations of endangered species besieged by other threats finally fall to an outbreak of a disease.

For instance, canine distemper would've killed off the formerly endangered black-footed ferret in the U.S. if it weren't for a captive-breeding program.

Russia's tigers are dispersed across a large-enough area that distemper would likely not be their death knell.

But if canine distemper broke out in more isolated tiger populations, such as in India, it could be, as WVI put it, "the final straw that makes extinction inevitable."

http://news.nationalgeographic.com/news/2013/06/130612-canine-distemper-virus-health-tigers-science-animals/
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Full Throttle
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A recent study of Amur tiger prey preferences, including photographic evidence of tiger killed boar, red deer and a bear of undetermined species:

Posted Image

From left to right:

* Изюбрь - Manchurian wapiti (Cervus canadensis xanthopygus)
* Кабан - Wild boar (Sus scrofa)
* Пятнистый олень - Sika deer (Cervus nippon)
* Европейская косуля - Siberian roe deer (Capreolus pygargus)
* Медведь - Bear (Ursus...)
* Другие - Others
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Canidae
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Full Throttle
Jun 27 2013, 05:43 AM
A recent study of Amur tiger prey preferences, including photographic evidence of tiger killed boar, red deer and a bear of undetermined species:

Posted Image

From left to right:

* Изюбрь - Manchurian wapiti (Cervus canadensis xanthopygus)
* Кабан - Wild boar (Sus scrofa)
* Пятнистый олень - Sika deer (Cervus nippon)
* Европейская косуля - Siberian roe deer (Capreolus pygargus)
* Медведь - Bear (Ursus...)
* Другие - Others
Nice find Full Throttle, such pictures are often rare - do you have a link to the study or know which they are from?
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Taipan
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Human Activities Threaten Sumatran Tiger Population

June 26, 2013 — Sumatran tigers, found exclusively on the Indonesian island of Sumatra, are on the brink of extinction. By optimistic estimates, perhaps 400 individuals survive. But the exact the number and locations of the island's dwindling tiger population has been up for debate.
Virginia Tech and World Wildlife Fund researchers have found that tigers in central Sumatra live at very low densities, lower than previously believed, according to a study in the April 2013 issue of Oryx -- The International Journal of Conservation.
The findings by Sunarto, who earned his doctorate from Virginia Tech in 2011, and co-researchers Marcella Kelly, an associate professor of wildlife in the College of Natural Resources and Environment, and Erin Poor of East Lansing, Mich., a doctoral student studying wildlife science and geospatial environmental analysis in the college, suggest that high levels of human activity limit the tiger population.
Researchers studied areas and habitat types not previously surveyed, which could inform interventions needed to save the tiger.
"Tigers are not only threatened by habitat loss from deforestation and poaching; they are also very sensitive to human disturbance," said Sunarto, a native of Indonesia, where people typically have one name. "They cannot survive in areas without adequate understory, but they are also threatened in seemingly suitable forests when there is too much human activity."
The smallest surviving tiger subspecies, Sumatran tigers are extremely elusive and may live at densities as low as one cat per 40 square miles. This is the first study to compare the density of Sumatran tigers across various forest types, including the previously unstudied peat land. The research applied spatial estimation techniques to provide better accuracy of tiger density than previous studies.
Sunarto, a tiger and elephant specialist with World Wildlife Fund-Indonesia, collaborated on the paper with Kelly, Professor Emeritus Michael Vaughan, and Sybille Klenzendorf, managing director of WWF's Species Conservation Program, who earned her master's and doctoral degrees in wildlife science from Virginia Tech. The WWF field team collected data in partnership with the Indonesian Ministry of Forestry staff.
"Getting evidence of the tigers' presence was difficult," Kelly said. "It took an average of 590 days for camera traps to get an image of each individual tiger recorded."
"We believe the low detection of tigers in the study area of central Sumatra was a result of the high level of human activity -- farming, hunting, trapping, and gathering of forest products," Sunarto said. "We found a low population of tigers in these areas, even when there was an abundance of prey animals."
Legal protection of an area, followed by intensive management, can reduce the level of human disturbance and facilitate the recovery of the habitat and as well as tiger numbers. The researchers documented a potentially stable tiger population in the study region's Tesso Nilo Park, where legal efforts are in place to discourage destructive human activities.
The study -- "Threatened predator on the equator: Multi-point abundance estimates of the tiger Panthera tigris in central Sumatra" -- indicates that more intensive monitoring and proactive management of tiger populations and their habitats are crucial or this tiger subspecies will soon follow the fate of its extinct Javan and Balinese relatives.

Posted Image
Sumatran tigers are threatened with extinction; it is estimated that fewer than 400 currently survive in the wild.

http://www.sciencedaily.com/releases/2013/06/130626183925.htm




Journal Reference:
Sunarto, Marcella J. Kelly, Sybille Klenzendorf, Michael R. Vaughan, Zulfahmi, M.B. Hutajulu, Karmila Parakkasi. Threatened predator on the equator: multi-point abundance estimates of the tiger Panthera tigris in central Sumatra. Oryx, 2013; 47 (02): 211 DOI: 10.1017/S0030605311001530

Abstract
Information on spatial and temporal variation in abundance is crucial for effective management of wildlife. Yet abundance estimates for the Critically Endangered Sumatran tiger Panthera tigris sumatrae are lacking from Riau, the province historically believed to hold the largest percentage of this subspecies. Recently, this area has had one of the highest global rates of deforestation. Using camera traps we investigated tiger abundance across peatland, flat lowland, and hilly lowland forest types in the province, and over time, in the newly established Tesso Nilo National Park, central Sumatra. We estimated densities using spatially explicit capture–recapture, calculated with DENSITY, and traditional capture–recapture models, calculated with CAPTURE. With spatially explicit capture–recapture the lowest tiger density (0.34 ± SE 0.24 per 100 km2) was estimated in the hilly lowland forest of Rimbang Baling and the highest (0.87 ± SE 0.33 per 100 km2) in the flat lowland forest of the Park. Repeated surveys in the Park documented densities of 0.63 ± SE 0.28 in 2005 to 0.87 ± SE 0.33 per 100 km2 in 2008. Compared to traditional capture–recapture the spatially explicit capture–recapture approach resulted in estimates 50% lower. Estimates of tiger density from this study were lower than most previous estimates in other parts of Sumatra. High levels of human activity in the area appear to limit tigers. The results of this study, which covered areas and habitat types not previously surveyed, are important for overall population estimates across the island, provide insight into the response of carnivores to habitat loss, and are relevant to the interventions needed to save the tiger.

http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=8893960
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Isolated Tigers Travel Surprising Lands to Find Mates
Protecting undeveloped land could save the big cat, scientists say.


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Bengal tigers in India travel undeveloped strips of land to find mates, a new study shows.

Photograph by Frans Lanting, National Geographic
Brian Handwerk
for National Geographic
Published July 30, 2013

The tiger Shere Khan was lord in Rudyard Kipling's Jungle Book, but his modern-day descendants are king no more: The big cats have seen their central Indian forests dwindle and fracture.

The remaining tigers are only surviving by moving through critical—but unprotected—corridors of land that link distant populations, a new study says.

Using hair and fecal samples, Sandeep Sharma, of the Smithsonian Conservation Biology Institute, and team studied genes from 273 individual tigers that live in four distinct locations within India's 17,375-square-mile (45,000-square-kilometer) Satpura-Maikal region.

Tigers once roamed across Asia from Turkey to the Russian Far East, but have vanished from over 93 percent of that range.

The 20th century was especially tough on the now-endangered beasts, when three subspecies became extinct, leaving six—all of which are at risk. (See a National Geographic magazine interactive of big cats in danger.)

At a glance the region's tigers seem to live in four populations, each occupying its own territory in what's called a designated tiger conservation landscape, or TCL. Those are Kanha-Phen, Pachmari-Satpura-Bori, Melghat, and Pench.

But the genetic study suggests otherwise: Corridors of woods and undeveloped land up to 125 miles (200 kilometers) long actually link Kanha and Pench into a single genetic unit, and Satpura-Melghat into a second.

That means the four populations of tigers are breeding as two much larger populations—and keeping their genetic diversity alive in the process.

Corridors also aid tiger survival on the ground, Sharma said, making the cats more likely to withstand many types of threats.

"If one of two connected populations drops, say because of poaching or some other factor, the other can expand and repopulate the area," he explained. But if these corridors aren't protected as wildlife habitat by the government or other entities, the land may be developed and leave the tigers in "islands."

If this happens, "eventually they are doomed."

Tiger Family Tree

Sharma and colleagues looked at the tiger population tree in the Satpura-Maikal region, which has seen dramatic declines in tiger habitat.

The team found two distinct periods in which tigers' genetic populations divided rapidly, and each was tied to known historical events.

"One was about 700 years ago, and that's [around] the time when Mughal invaders came into the region and they started clearing river valleys and intensified agriculture in those valleys," he said, noting that the major threat facing tigers at that time was habitat loss.

The second period was about 200 years ago, Sharma said, when the British Empire not only felled trees to fulfill its enormous need for timber, but also introduced a vast arsenal of firearms that dramatically increased the number of tigers killed by hunters.

"You can really see these two distinct patterns of genetic subdivision in this population," said Sharma, whose study appeared July 30 in Proceedings of the Royal Society B: Biological Sciences.

Sharma and colleagues also used their data to look back in time some 2,000 years and compare the present situation with ancient patterns of tiger gene flow.

Only tigers in those populations still connected by these corridors are maintaining similar levels of gene flow [to what] we saw historically," he explained.

In areas "that have lost the corridors, the gene flow has significantly decreased."

Living With Tigers

By illuminating the past and present the study provides a roadmap for where future conservation efforts must be focused—keeping the fragile links open between different population groups, according to the authors.

Today, however, these tiger corridors have no legal protection. They are simply forest landscapes, used by local peoples and subject to development, including mining in one of India's prime coal regions.

Earlier this year the Indian Ministry of Environment and Forests gave Coal India Limited permission for coal-mining development in the crucial Satpura-Pench wildlife corridor.

Officials stated publicly that the mine is an underground rather than open facility, and thus shouldn't interfere with the tigers' migratory corridor.

But Sharma is unconvinced, suggesting that mining brings with it settlements, roads, and infrastructure, which can be a major threat to the corridors just at the time when hard genetic data have shown that tigers are using them to travel and reproduce.

Conservationist Luke Dollar, a National Geographic Society Emerging Explorer who manages the society's Big Cats Initiative, said the tough decisions faced here are common where big cats prowl.

"India has half of all the remaining tigers on Earth, but it's also a perfect example of what we face in big-cat conservation, whether it be here or in Africa," he said. "The cats and people are colliding in a struggle for space and existence."

Dramatic Interventions

Where populations become very isolated, dramatic human interventions may be necessary to save inbred cats, Dollar added.

For instance, in 1995 Texas cougars were released to breed with and revitalize a Florida panther population so small and inbred that Dollar described them as "walking dead."

Protecting wildlife corridors is the best way to avoid such drastic measures and offers a better chance of success as well.

"In conservation it's not individuals or individual populations that we worry about if we're going to play the long game," he said.

"We worry about the overall genetic integrity of the species, which is exactly where corridors are critical as the mechanism for genetic exchange that can maintain a robust population."

"Floating in a Human Sea"

Sharma stressed that tigers need to be managed not with a myopic approach, as isolated populations, but as one big population connected by corridors.

"India has the second largest human population in the world, and these tigers are floating in a human sea," he said.

"We can't create new tiger habitat, and there is no hope outside these areas. The only hope is these corridors. If you cut them down, and fragment these populations, eventually they will only exist in history books."

http://news.nationalgeographic.com/news/2013/07/130730-tigers-india-corridors-animals-science-environment/




Forest corridors maintain historical gene flow in a tiger metapopulation in the highlands of central India
Sandeep Sharma1,2,3⇑, Trishna Dutta1,2,4, Jesús E. Maldonado1, Thomas C. Wood2, Hemendra Singh Panwar5 and John Seidensticker1
Published 31 July 2013 doi: 10.1098/rspb.2013.1506
Proc. R. Soc. B 22 September 2013 vol. 280 no. 1767 20131506

Abstract
Understanding the patterns of gene flow of an endangered species metapopulation occupying a fragmented habitat is crucial for landscape-level conservation planning and devising effective conservation strategies. Tigers (Panthera tigris) are globally endangered and their populations are highly fragmented and exist in a few isolated metapopulations across their range. We used multi-locus genotypic data from 273 individual tigers (Panthera tigris tigris) from four tiger populations of the Satpura–Maikal landscape of central India to determine whether the corridors in this landscape are functional. This 45 000 km2 landscape contains 17% of India's tiger population and 12% of its tiger habitat. We applied Bayesian and coalescent-based analyses to estimate contemporary and historical gene flow among these populations and to infer their evolutionary history. We found that the tiger metapopulation in central India has high rates of historical and contemporary gene flow. The tests for population history reveal that tigers populated central India about 10 000 years ago. Their population subdivision began about 1000 years ago and accelerated about 200 years ago owing to habitat fragmentation, leading to four spatially separated populations. These four populations have been in migration–drift equilibrium maintained by high gene flow. We found the highest rates of contemporary gene flow in populations that are connected by forest corridors. This information is highly relevant to conservation practitioners and policy makers, because deforestation, road widening and mining are imminent threats to these corridors.

http://rspb.royalsocietypublishing.org/content/280/1767/20131506.abstract
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