Species Facts: Tiger

Tigers are perhaps the most popular cats after our own domestic pet.

If we could do it safely, most of us would enjoy touching a living tiger’s fur, petting the cat and feeling its warmth and power.

Here you go.

If . . .

Meanwhile, some people choose to take that fur, and other body parts, for their own use.

Others merely wish their struggle to make a living didn’t include man-eating tigers.

These beautiful but dangerous cats aren’t just zoo attractions and conservation symbols – tigers are also caught up in a complex mess that includes exploitation and human-tiger conflict

Who’s this?

The most fabulous cat is difficult to miss.

But why is it orange? This color really shows up against the tiger’s typical green, gray, or white background. You’d think natural selection would disapprove of it in an ambush predator, but orange apparently works for tigers somehow.

And what about those stripes?

There are no spotted tigers. (Werdelin and Olsson) Experts once thought that vertical stripes helped tigers blend into grass, but more research suggests this isn’t the case. (Allen and others)

Instead, stripes may mess with the prey’s vision. A tiger’s coat patterns have a “spatial frequency” that’s similar to most backgrounds (Godfrey and others)

In plain English, vertical stripes may make tigers look blurry, like the bottom picture here.

If this is true, then the real question is, why don’t more cats have vertical stripes? (Godfrey and others)

What does it look like?

If you’ve never taken a tape measure to a tiger, try to imagine a cat with 8 feet of head and body and another 3-1/2 feet of tail, weighing over 700 pounds. (Cat Specialist Group)

That’s the big one, an Amur (Siberian) tiger. They’re smaller in the south. (Luo and others)

An average Sumatran tiger is “only” 5 feet long, with a 3-foot tail and a weight of 165 pounds on average. (Cat Specialist Group)

Of course, no real tiger is average.

Each tiger’s stripe pattern is unique. (Cat Specialist Group)

Males and females come in different sizes, and tiger colors and sizes also vary a lot. (Luo and others)

The Amur tiger even fattens up in the fall and grows a winter coat! (Heptner and Sludskii)

How friendly/dangerous is it?

Amur tigers usually try to avoid people, but Bengal tiger-human conflict has been a severe problem in India. (Heptner and Sludskii)

See Heptner and Sludskii, and also Thakur for more details.

This problem continues today. Between 1990 and 2009, there were over 800 reported cases of conflict, and probably many more that went unreported. (Chowdhury and others; Thakur)

There are indirect costs, too. Some 3,000 “tiger-widows” are struggling to support their families in India’s Sundarban region. Their society stigmatizes widows anyway, but it’s worse for these women. (Chowdhury and others)

Why is it on the IUCN Red List?

Historically, tigers lived in most of Asia, including the regions between the Caspian and Aral seas, as well as southeastern Russa and Indonesia’s Sunda Islands. (Luo and others)

A century ago, the world’s tiger population was estimated at 100,000. (Panthera)

In 1964, it was down to 15,000. (Heptner and Sludskii)

An estimated 5,000-7,000 tigers were on earth in 1998. (Goodrich and others)

Today, tigers have lost over 90% of their historic range, and conservationists now track them by subspecies. (Cat Specialist Group; Goodrich and others; Luo and others)

Out of the estimated 3,000-4,000 remaining tigers, there are, per Luo and others:

  • Less than 500 Amur tigers
  • 50 Amoy (South China) tigers in captivity; these are considered extinct in the wild
  • 400-500 Sumatran tigers
  • 1800 or less Indochinese tigers

That’s not the whole problem. Out of those small numbers, only some are breeding.

A number of tiger protection efforts are ongoing today. The overall goal is to raise the total number of tigers to 6000 by 2022.

We are fascinated by the tiger because it is terrifying and yet so beautiful – beautiful enough that we sometimes can overcome our fear to try to help it before the whole species disappears forever.


Images:
Featured image: Pixel-maker at Pixabay. Public Domain.

Royal Bengal tiger, camera trap. Dasdhritiman. CC BY-SA 4.0.

Tiger tracks in snow, Figure 83 in Heptner, V. G., and Sludskii, A. A. 1972. Mammals of the Soviet Union, volume II, part 2: Carnivora (hyaenas and cats). Moscow: Vysshaya Shkola Publishers. English translation by Rao, P.M., 1992. General editor: Kothekar, V. S. New Delhi: Amerind Publishing.


Sources:

Allen, W. L.; Cuthill, I. C.; Scott-Samuel, N. E.; and Baddeley, R. 2011. Why the leopard got its spots: relating pattern development to ecology in felids. Proceedings of the Royal Society B. 278:1373-1380.

Chowdhury, A. N.; Brahma, A.; Mondal, R.; and Biswas, M. K. 2016. Stigma of tiger attack: Study of tiger-widows from Sundarban Delta, India. Journal of Indian Psychiatry. 58(1):12-19.

Chundawat, R. S.; Khan, J. A.; and Mallon, D. P. 2011. Panthera tigris ssp. tigris. The IUCN Red List of Threatened Species 2011:e.T136899A4348945.

Godfrey, D.; Lythgoe, J. N.; and Rumball, D. A. 1987. Zebra stripes and tiger stripes: the spatial frequency distribution of the pattern compared to that of the background is significant in display and crypsis. Biological Journal of the Linnaean Society. 32(4):427-433.  

Goodrich, J.; Lynam, A.; Miguelle, D.; Wibisono, H.; and others. 2015. Panthera tigris. The IUCN Red List of Threatened Species 2015:3.T15955A50659951.

Heptner, V. G., and Sludskii, A. A. 1972. Mammals of the Soviet Union, volume II, part 2: Carnivora (hyaenas and cats). Moscow: Vysshaya Shkola Publishers. English translation by Rao, P.M., 1992. General editor: Kothekar, V. S. New Delhi: Amerind Publishing.

Linkie, M.; Wibisono, H. T.; Martyr, D. J.; and Sunarto, S. 2008. Panthera tigris ssp. sumatrae. The IUCN Red List of Threatened Species 2008:e.T15966A5334836.

Luo, S-J; Kim, J-H.; Johnson, W. E.; van der Welt, J.; Martenson, J.; and others. 2004. Phylogeography and genetic ancestry of tigers (Panthera tigris). PLoS Biology. 2(12):e442.

Thakur, J. February 3, 2017. “In Sunderbans, no one cares about villagers who go missing in animal attacks.” Hindustan Times. http://www.hindustantimes.com/india-news/in-sunderbans-no-one-cares-about-villagers-who-go-missing-in-animal-attacks/story-qBfi3zcR9OnU0EZXNgGNyJ.html Last accessed September 13, 2017.

Werdelin, L., and Olsson, L. 1997. How the leopard got its spots: a phylogenetic view off the evolution of felid coat patterns. Biological Journal of the Linnaean Society. 62:383-400

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

w

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.