ON THE EDGE OF EXTINCTION - A - THE TIGER (Panthera tigris)

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peter

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01-15-2018, 12:25 PM

(01-14-2018, 12:47 PM)GrizzlyClaws Wrote: I was also suspecting that the diversity within Amur tiger population could be the result of the admixture with other paleo tiger population.

Technically, the Manchurian tiger is a subtype of the Amur tiger that is different from other regular Amur tigers. It is possible that they got more admixture from the Wanhsien tiger than the regular Amur tiger? Since the Manchurian tiger was less cursorial and more forest adapted than the regular Amur tiger, and the Wanhsien tiger was also a pure forest type of tiger that used to disperse all over of China from north to south before the Toba eruption.

However, the Manchurian tiger right now is also functionally extinct in the wild, maybe only few individuals remain in the captivities around the world, so we can only speculate right now.

1 - THE EYE OF THE BEHOLDER

In the last three decades or so, I read everything I could about tiger evolution. Summaries were made to limit the amount of information. Every now and then, I found a book about Amur tigers or articles written by those who Amur tigers hunted in the first decades of the last century. Later, I read what was availble about skulls. You know I also photographed and measured quite a few big cat skulls. In between, I talked to biologists, hunters and trainers. In the facilities I visited, I watched big cats for a long time. Every now and then, I measured and weighed a few.

I'm not saying that the attempt to get to a bit of insight was a complete failure, but it took a lot of time to understand that you need more than your brain to get to a bit of understanding. People who moved to wild regions often say they learned to develop their senses. All of them and then some more. They also said a new dimension seemed to open up after they had adjusted. Meaby something similar is happening when you focus for many years on something you're really interested in.

What I'm saying is there are different ways to learn and different ways to consume and digest information. Not everything you learn can be captured in words. In the end, after a long time, a picture emerges. I don't think it's related to information collected by others. It's also not a result of a particular incident. It seems to be a product of digesting everything you saw, read, heard and felt. It's personal. For those involved, it's a kind of insight based on what he or she considers as essential. Others no doubt would describe is as a product of fixation or imagination. Both are true to a degree. It depends on the eye of the beholder, that is.

2 - SUNDA TIGERS

There is a fundamental difference between tigers from what's now Indonesia and tigers from other regions in Asia. Indonesian tigers, and those from Sumatra in particular, seem older and more 'wild at heart'. This regarding tigers today (not Manchurian tigers).

They evolved in a part of Asia where humans, back then, were few and far between. Over the years, they adapted to ever changing conditions. When they had nowhere left to go, a kind of war between tigers and humans developed. On Java, tigers, after it had been invaded by the Dutch, faced similar conditions as Amoy tigers in southeastern China a century later in that they often had no other option but to hunt domestic animals and humans. The reports I read suggest they, like lions or wolves, might have hunted in small packs in the end. The last Javan tigers inhabited remote, densely forested and elevated parts of Java. Although some think Java still has tigers, it's very unlikely. But they still very much exist in the minds of many people and you never know. Meaby Phatio will find evidence one day.

Bali had less people and there was a clear separation between humans and tigers. There was no real need to hunt them. The problem is that Bali was, and is, a very nice place to visit. In the first decades of the last century, hunters saw Bali as a kind of paradise. The island is limited in size and if you had some time to spare, you had a decent chance to get a shot at a tiger that was considered as something special back then. Bali tigers disappeared in the fifties of the last century.

Sumatra tigers had more room than Javan and Bali tigers. Sumatra is a very large island, still largely covered with forest. It had, and still has, a lot of wildlife and few people. For a very long time, tigers, apart from a few regions, were not hunted. After the Dutch started operations, the situation changed. Tigers didn't take it lying down, as it was a fight about territory. During the second half of the 19th century, Sumatra could have been the most dangerous place to live. India also had a reputation back then, but compared to Sumatra, it wasn't that bad. Today, Sumatra has 300 - 800 tigers. Although they, regarding humans, behave in a different way, tigers and humans still perish during conflicts. Confirmed man-eaters, however, seem to be a thing of the past.

3 - TIGERS OF NORTHERN ASIA

Apart from a few exceptions, the region between the Caspian Sea and the Russian Far East (RFE) always was thinly populated. If there was a region where tigers had the opportunity to hang on for a very long time, it would have been there. Although parts of this region are suited for tigers, the conditions never quite compared to India, southeast Asia, Sumatra, Central China or Manchuria. My guess is that the number of tigers between, say, Lake Aral and Lake Baikal (north of the Gobi) always was very limited. For this reason, it's likely they traveled a lot. As most of them had plenty of room to stay out of sight, quite many settled, and bred, in suitable parts in central and eastern parts of Siberia.

Although research says that Caspian tigers moved east, it's also likely that tigers in northern China and southeastern Russia would have moved west every now and then. When fire-arms were introduced, the region between the Caspian and Lake Baikal lost its tigers. By then, however, P. tigris altaica and P. tigris virgata were just about one and the same.

The region between Lake Baikal, Beijing (in the south) and what is now South-Korea (including the islands) in the southeast always had tigers in the Holocene. Although large individuals have been shot in all parts, heavyweights were mostly seen in hotspots. One of these could have been the alleged former Imperial Hunting Reserve, just southwest of Sichote-Alin and west of what is now North-Korea. Manchuria, north of the former Imperial Hunting Reserve, could have been another.

4 - AMUR AND MANCHURIAN TIGERS

Although tigers from different parts of northeastern Asia no doubt interbred, there could have been two quite distinct types. Typical Amur tigers are long, tall and quite large-skulled, but not as robust as one would expect. As a result of a population bottleneck, variation in size today is not as outspoken as in most other subspecies. My guess is it never was because of the demanding conditions. Manchurian tigers, also large, seemed (as extinct) to be a bit more robust and, regarding humans, more aggressive. My guess is they showed more variation because of both better conditions and more influx (northern China).

We can only guess about the size of the average Manchurian and Amur tiger, as only few reported about the tigers they shot. When they, only the largest featured. In the first decades of the last century, George Jankowski considered a 550-pound tiger as large. His sons later shot a male possibly exceeding 650 pounds near the Sungari River (Manchuria). Tigers of similar size were shot by others as well. Based on what I read, it's likely that some individuals shot in the 20th century well exceeded even 700 pounds.

These giants, however, were not accepted by authorities. In a report on the size of Amur tigers published not so long ago, the 560-pound male shot by Baikov in 1911 near the Russian-Korean border still tops the list. Remarkable, as Baikov's reports about two other, much heavier, males were dismissed.

5 - PLEISTOCENE TIGERS

As to P. tigris acutidens. Although bones of this Pleistocene tiger have been found near the land bridge between Asia and America, he wasn't able to cross it. There's, however, no question that he reached the northeastern tip of Asia. Although not suited to deal with large empty regions, P. tigris acutidens must have been accustomed to exceptional conditions. Same for P. tigris altaica. They too have to deal with long and severe winters and they too are able to survive and breed, whereas timber wolves struggle with energy deficits.

Could P. tigris acutidens have managed to hold on until the Holocene? And if so, could he have mixed with Caspian tigers moving east in the Middle Pleistocene (assumption) or the Holocene (fact). Based on what I read about cave lions in western Europe, the answer is affirmative. The missing link between P. tigris virgata and P. tigris altaica could be P. tigris acutidens.

My guess is that P. tigris acutidens and P. tigris virgata bred. Amur tigers and Sumatran tigers breed in captivity, so size is not decisive. The result, a smaller but more active animal, would have thrived in northeastern Asia. He still does.

Could the robust Manchurian tiger have survived in northeastern Asia? Not likely. Wolves, much more active, don't make it and robust specialists unable to walk many miles a day every day all year long every year would struggle as well. In the RFE in winter, short rushes are not enough to succeed. Arctic long-distance walking can't be avoided. Brown bears, also large, can survive because they are omnivores including protein (fish) when possible. But brown bears in northeastern Siberia, except for a few freaks, are not much larger (heavier) than P. tigris altaica. The Ussuri brown bear, Ursus arctos lasiotus, is a larger animal, because the conditions in the RFE are better than in northeastern Siberia. They're also larger than Amur tigers, but the difference in size apparently is not large to displace male tigers. Males of both species, and tigers in particular, hunt females and immature animals, but they seem to avoid each other. A delicate balance.

6 - CAPTIVE AMUR TIGERS THEN AND NOW

During the days of the Sovjet-Union, Amur tigers were exported to eastern Europe in particular. Later, they also were seen in other countries. China no doubt has a few Manchurian tigers. In those days, just like in the wild, some were long, tall and large but not very robust, whereas others were both very large and exceptionally massive. Biologists no doubt would consider it as a result of individual variation. Maybe it is, but it's also possible that there really were two (or three) different types. Hunters distinguished between Amur and Korean tigers. I also know they distinguished between Amur and Manchurian tigers.

Most captive Amur tigers, although a bit larger and heavier, are very similar to their wild relatives, but some individuals seem very different from others. I saw a few of them. What struck me most was the difference in attitude. Most Amur tigers are quiet and stable animals, but the giants were very different. Keepers knew and kept their distance. They too distinguished between Amur and Manchurian tigers. The ones I talked to told me that they considered them as prehistoric monsters. As a result of their size and attitude, accidents were few.

The Amur tigers exploding in my presence a few times were true Amur tigers. Keepers who saw Manchurian tigers explode told me that they often called it a day after some time. They felt watched all the time and often feared for their life. Clever animals, they were. Most Manchurian male tigers never bred, because they were considered as too volatile and too dangerous. Not a few of them killed their partner right away, especially in Chinese facilities. I still see exceptional males well exceeding 600 pounds every now and then, but they're definitely different from the animals I saw a long time ago.

7 - A FEW SCANS

a - Marco Polo. He wrote that the 'striped lions' (tigers) in northern China were larger than those of Babylon (he was referring to Panthera leo persica). These 'striped lions' were used to hunt all kinds of game, including bears. He was amazed at the ferocity he saw.

Based on the map below, it's safe to state that Marco Polo wasn't referring to Amur tigers but to tigers in northern China (P. tigris amoyensis):