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Tigers of North-Eastern India
Tigers of North-Eastern India
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Tigers of North-Eastern India
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The main factors involved may be muscular robusticity and stockiness. As I have explained in my previous posts, both of them may be due to predictable vegetation in these areas. The tiger must not be having problems or finding it difficult to traverse these forests. So, it clearly has in mind on how to evolve in next generation. So, it has the opportunity to express it's highest potential in terms of morphology and size. So, they may be evolving to their highest potential in terms of robusticity and stockiness.
Or there may be other factor too as it is explained in the essay. The genes of indo chinese tigers can also be a factor. Though it may take time to mix these genes into the bengal dna as per the conditions of the subcontinent, they seem to be becoming more robust this way. A sample comparison between northeast tiger and the tigers from rest of India(at equal shoulder heights), look how impressive are northeast tigers, l  *This image is copyright of its original author
Taking into consideration the type of forests in north east india, there are mainly two kinds.
1. Tropical evergreen forest, 2. Hollong forest (Dipterocarpus) Of the total forest area of around 68 million hectares in India, the North-Eastern states account for over 17 million hectares, roughly one-fourth of the forest area of the country. All the states of North-East India, with the exception of Assam, have 50–80 % of their area under forests. High temperatures, combined with heavy to very heavy rains, have stimulated the growth of forests at lower levels. Even in the mountainous regions, there are heavy rains in summer, and lower temperatures during winter don’t cause excessive evapotranspiration and thus limit the possibility of any moisture stress in the soil. The forests in the hilly regions, despite the destruction of forests by slash and burn cultivation, have survived and are regenerated. These forests have enormous variation in their typology and floral characteristics, ranging from tropical evergreen at lower altitude in upper Brahmaputra valley to pine forests in the Himalayas and birch–rhododendron scrub at still higher levels. Dipterocarpus macrocarpus (Hollong in Assamese) and Mesua ferrea (Nahar in Assamese) are the principal type trees of Assam valley tropical evergreen forests. In the tropical moist deciduous forests, Shorea robusta is the principal species with several associates likeSchima wallichii (Makna Sal). The subtropical wet hill forests, as in Meghalaya, have several varieties of oak (Quercus spp.). Richness of flora because of the wet hills presents a climate condition, which combines the characteristics of tropical as well as temperate climate. At higher altitudes, mixed coniferous and coniferous forests occur followed by sub-alpine pastures, rhododendrons and scrubs at still higher altitudes. North-East India is known for its biodiversity. It is one of the two biodiversity hotspots of India. Half the total number of floral species, known in India, occurs here, and the region forms the richest reservoir of genetic variability. An important aspect of the forests of the region is the profusion of orchids. The North-East region has 876 orchid species, which constitute 70 % of the total orchid flora of India. To preserve the biodiversity of the region, a number of biospheres, national parks and wildlife sanctuaries (2004) are established in the region. Hollong trees,  *This image is copyright of its original author  *This image is copyright of its original author Tropical evergreen forests,  *This image is copyright of its original author  *This image is copyright of its original author
good quality picture of this photo,
 *This image is copyright of its original author
PARVEZ
Good posts, especially those on landscapes and genes. The post on genes has very interesting info about tigers in northeastern India. I asked the mods to move a copy of that post to the tiger extinction thread. As to the post on genes. In many ways, northeastern India is a crossroads. It's close to the Himalayas, Bengal, southwestern China and Burma (Myanmar). My guess is all of these regions produced different tigers. When they met in northeastern India, a new type could have been the result. One would, however, expect to find (traces of) the original types as well. Based on what I have, I would distinguish between 3 local types (the Himalayas, the alluvial floodplains and tigers from the hilly southeast). Almost a century ago, males in the extreme southeast of Assam (Naga Hills) averaged 8.7 'between pegs' in total length. Only one of them exceeded 9 feet. The 2 males weighed, if correct, ranged between 340-355 pounds roughly. Hill tigers, they were. Male tigers from the floodplains, about half a feet longer, were among the heaviest weighed in that period (461 pounds). The mountain tigers in the extreme northwest could be different from both. My guess is they were larger. I've always been interested in the tigers ranging between the extreme southwest of China and the extreme northeast of Assam. Most biologists decided western China tigers belonged to Panthera tigris amoyensis, but there are reasons for doubt. Same story for Indochinese tigers. Both regions (southern and central China and all of Indochina) are too large and too different for one tiger subspecies. If you decide for subspecies, you got to do it right and collect as much information as possible in order to refine the proposal of Pocock on 8 tiger subspecies. If you don't, chances are the proposal will disintegrate sooner or later. If you decide for one tiger subspecies for all of mainland Asia, like Kitchener proposed, you will lose a lot of details. Managers wouldn't mind, but those interested in details would. Maybe we need a few good maps of Assam in order to understand the summary of the article in post 25. See what you can do. 
This is the natural occurrence between the different subspecies that share a geographical proximity.
Without the human interference, the different tiger subspecies that shared a border used to have even more genetic exchange. Not only the Northeast Indian tigers, the South China tigers in the South China also used to have a lot of mixture with the Indochinese tiger. (12-30-2016, 07:23 PM)parvez Wrote: The main factors involved may be muscular robusticity and stockiness. As I have explained in my previous posts, both of them may be due to predictable vegetation in these areas. The tiger must not be having problems or finding it difficult to traverse these forests. So, it clearly has in mind on how to evolve in next generation. So, it has the opportunity to express it's highest potential in terms of morphology and size. So, they may be evolving to their highest potential in terms of robusticity and stockiness. Agree, although the Indochinese tigers are generally smaller, but it doesn't mean that their offspring with the Bengal tigers would also become smaller. The hybrid mutation could likely trigger the gigantism gene.
Sorry peter I didn't notice your post. Now only I am seeing it. As per my observation the Himalayas obstruct the movements of tigers of different subspecies. So the tigers at foothills of Himalayas must be normal Bengal tigers. Even among northeast tigers due to movement from one habitat to other I do not see any differentiation in their genetics. They must be having same unique genes Imo. Perhaps Kashmir tigers must have had admixture of Siberian or Caspian genes. Do you have any records or pictures of Kashmir and Pakistan tigers. It will be interesting to know if they were stocky just like Assam tigers as they must have mixed with either Caspian or Siberian genes. But your data on Himalayan tigers too is very interesting. In my opinion Assam tigers for their length must be overweight compared to tigers of other regions for their length. Did you observe that feature? Or is it that Assam tigers are growing stocky only these days? It will be interesting to know all these points.
(01-04-2017, 01:08 PM)parvez Wrote: Sorry peter I didn't notice your post. Now only I am seeing it. As per my observation the Himalayas obstruct the movements of tigers of different subspecies. So the tigers at foothills of Himalayas must be normal Bengal tigers. Even among northeast tigers due to movement from one habitat to other I do not see any differentiation in their genetics. They must be having same unique genes Imo. Perhaps Kashmir tigers must have had admixture of Siberian or Caspian genes. Do you have any records or pictures of Kashmir and Pakistan tigers. It will be interesting to know if they were stocky just like Assam tigers as they must have mixed with either Caspian or Siberian genes. But your data on Himalayan tigers too is very interesting. In my opinion Assam tigers for their length must be overweight compared to tigers of other regions for their length. Did you observe that feature? Or is it that Assam tigers are growing stocky only these days? It will be interesting to know all these points. I think the Amur-like gene should come from the Caspian tigers, since the Caspian tigers historically had resided on the belt of the silk road which was located to the geographical proximity of the northern India/Pakistan. 
Sanjay Shukla
Royal Bengal Tiger (Panthera tigris) I was lucky enough to see a tiger also in Kaziranga. I was in the Agoratoli (Eastern ) Range and the sun has gone down the horizon. I just wanted to see some of the Anti Poaching Camps. The determined and committed frontline staff in these camps has fought hard with the poachers to make this a safe place for rhinoceros now. The forester driving the vehicle was narrating me many stories of ambush with the poachers. Suddenly we saw one tiger moving ahead of us on the road. The light was pretty bad and distance was much. This was the best image which I could get before the tiger suddnly disappeared in the bushes. This was clicked at 20,000 ISO and 500 mm (equivalent to 750 mm).  *This image is copyright of its original author To my knowledge, this is the first "golden tabby" wild tiger photographed but I could be mistaken on that. 
Simply put, wow. A golden tabby in the wild with such a small population. What are the chances?
(01-11-2017, 10:38 PM)tigerluver Wrote: Simply put, wow. A golden tabby in the wild with such a small population. What are the chances? Very rare, I have read that further north the lighter the coat, so I would think the best chances of seeing a golden tabby/white tiger would be in the Northern Parts of India. But that may have nothing to do with the white gene, so who knows for sure. 
Manas tigers,
 *This image is copyright of its original author  *This image is copyright of its original author
Reconnecting wildlife habitats - Can Htamanthi Become a Source Site for Tigers?
In the last hundred years, tiger habitat has been significantly fragmented and transformed into isolated patches of habitats. A particular site can hold breeding females and a viable population (source), while a neighbouring one might have been depleted by poaching (sink). The key in this case is to recreate connectivity via corridors to allow the animals from source populations to disperse into sink habitats and to alleviate the damages when a disaster occurs Htamanthi Wildlife Sanctuary (2,151 km2) is roughly 80% closed forest that is semi-evergreen, deciduous, and teak bearing. Like many other tiger sanctuaries, it faces major threats to tiger habitat, prey, and the tigers themselves. However, past and present studies show that there is hope for the cats in this sanctuary. Myanmar conducted nationwide tiger surveys during 1999-2002. Three sites had confirmed tigers – Hukaung Valley, Htamanthi and Tanintharyi. Another study in the 1990s estimated the Htamanthi population of tigers to be about 15 individuals. Recent studies in Htamanthi indicated the continued presence of seven Asian wild cats – Tiger, Leopard, Clouded leopard, Golden cat, Marbled cat, Jungle cat, and Leopard cat. This diversity is indicative of a robust ecosystem with a solid prey base of herbivores such as Gaur, Sambar deer, Barking deer, and Eurasian wild pig. There have been few records of tigers moving across the greater Htamanthi region in recent years. But decades ago, the entire stretch of land was connected, with tigers, elephants and other animals dispersing freely across international borders. Today, limitations to tiger movement between India and Myanmar don’t arise from lack of green cover, but more from small-scale hunting and lack of prey. Recently, tiger tracks were reported extensively in both the buffer zone and villages surrounding Htamanthi by community engagement teams. In the same period, patrol teams, confirmed the presence of other threatened species throughout the sanctuary. In the core management area, three tigers were captured by the same camera trap (picture above). This suggests that the core area is crucial to the social relationships of these tigers. Other tigers were also recently photographed in Htamanthi. Htamanthi sits close to the international border close to where there are important tiger landscapes in India. In February 2016, a tiger, dispersing through the community-managed forests of the Nagaland in India, was unfortunately shot by villagers. The first official record of tigers in Nagaland in the past decade, this incident brings to light that there is still movement of tigers through this region. Immediately after the tiger was discovered and photographed, WCS-India worked with the Nagaland State Forest Department and WCS-Myanmar to confirm that this tiger was not one of any of the known tigers of Myanmar. Following this incident WCS India, its local partner, Nagaland Wildlife and Biodiversity Conservation Trust, and the State Forest Department engaged with local community leaders in Nagaland to emphasize the importance of providing the occasional dispersing tigers with a free pass. And shortly thereafter these communities reported a possible second tiger to the Nagaland State Forest Department and to WCS. Their positive response shows us that, with support from conservationists, Nagaland can serve as a link between resident tiger populations in India, and habitats in Myanmar, such as Htamanthi. With good conditions for prey and being a manageable size, Htamanthi could host a vital transboundary source population. The success of the site through a source-sink model relies on securing habitat connectivity in the north (Hukaung Valley), the west (Naga Hills), and tiger reserves in India. Future study of potential connectivity for tigers between high-density source populations in India, such as the Kaziranga National Park and habitat in Myanmar, could guide future tiger recovery programmes in Myanmar. https://www.iucn.org/news/reconnecting-w...ite-tigers  *This image is copyright of its original author
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