Many big cats have large home ranges or territories. Cats like mountain lions or pumas, tigers and bobcats don’t live in big groups like lion prides. Instead, they live by themselves most of the time, except when a mother is raising cubs or sometimes when a male and female hang out together around mating time. Many people think tigers are beautiful and majestic, but keeping them in the wild seems to be kind of difficult—they are currently listed as endangered because tiger populations have decreased by 50% in the last 30 years or so4. Tigers are native to Asia, and Asia has a lot of people (4.4 billion in 2014). When human populations get really big, it’s had for other animals to coexist with us.
For tigers, population density depends upon the density of their prey, which may also be scarcer where human populations are expanding. Tigers commonly eat other mammals, like deer and other hoofstock which are known for being skittish and can be hard to catch. One model suggests that male Amur tigers must consume at least 25 prey per year, non-reproductive females consume 20 prey/year and mothers raising 4 cubs require 54 prey/year8. That is quite a lot when your prey is hard to find and catch, so it might make sense that tigers have a big home range. They have to search pretty far to find enough food when the food is also trying not to be found. Prey density is declining in native tiger habitat6. That makes getting enough to eat even harder. Sometimes people’s livestock are easier to get, which means that livestock depredation is one of the biggest reasons we see conflict between humans and tigers.
A tiger’s home range size can vary a lot depending on the place you’re looking at. One study in Thailand found that male tigers’ ranges were around 267–294 km and female’s ranges were around 70–84 km7. But a study in Bangladesh found that a couple females had an average home range of 14.2 km2, which is much smaller.
According to World Wildlife Fund (WWF), some of the current conservation projects for tigers in the wild are focused around preserving their habitat and reducing tiger-human conflict10. Because tigers need so much habitat for those big home ranges, one of the first steps in their conservation is preserving enough habitat to support a good sized population. In order to do that, organizations like WWF are working to try to influence agriculture, paper and timber industries, among others, to use sustainable practices that minimize loss of forest land. To reduce conflict with local communities, organizations like WWF rely on innovative solutions and education. In regions where the conflict most often occurs, some strategies might include scare tactics, negative conditioning and capturing tigers to assess their condition because tigers in good condition are not usually the ones who are desperate enough to attack humans and livestock9.
So what do these big sizes and big differences in home ranges mean for conservation? A lot! We know that in order to conserve tigers in the wild, we need to conserve big enough patches of their habitat for them to move through, ideally without running into and having conflicts with people. Because the density of their prey influences their feeding behavior and potentially the size of their range, we might have to consider how to maintain those species at good levels (and figure out what those good levels are). In order to reduce conflict with humans and hence reduce killings by humans, we need to learn more about how tiger home ranges change around people, and how tigers move through populated areas. Helping people build safe enclosures for their livestock might be one thing to try. Do you have any good ideas? Leave them in a comment below!!
Here are some of the sources I used. If you’re interested in tiger behavior or tiger conservation, you should let us know what articles and papers you like, too!
– Leorah McGinnis
- Athreya, Vidya. et al. “Movement and Activity Pattern of a Collared Tigress in a Human-dominated Landscape in Central India.” TROPICAL CONSERVATION SCIENCE1 (2014): 75-86. Web.
- Barlow, Adam. et al. “Femalle Tiger Panthera Tigris Home Range Size in the Bangladesh Sundarbans: The Value of This Mangrove Ecosystem for the Species’ Conservation.” ORYX1 (2011): 125-28. Web.
- Bhattarai, Babu, and Klaus Fischer. “Human-tiger Panthera Tigris Conflict and Its Perception in Bardia National Park, Nepal.” ORYX4 (2014): 522-28. Web.
- Chundawat, R.S., Habib, B., Karanth, U., Kawanishi, K., Ahmad Khan, J., Lynam, T., Miquelle, D., Nyhus, P., Sunarto, S., Tilson, R. & Sonam Wang 2011.Panthera tigris. The IUCN Red List of Threatened Species. Version 2014.3. <iucnredlist.org>. Downloaded on11 February 2015.
- Miller, C.s., M. Hebblewhite, Y.k. Petrunenko, I.v. Seryodkin, J.m. Goodrich, and D.g. Miquelle. “Amur Tiger (Panthera Tigris Altaica) Energetic Requirements: Implications for Conserving Wild Tigers.”Biological Conservation170 (2014): 120-29. Web.
- Simcharoen, Achara. et al. “Ecological Factors That Influence Sambar (Rusa Unicolor) Distribution and Abundance in Western Thailand: Implications for Tiger Conservation.” RAFFLES BULLETIN OF ZOOLOGY62 (2014): 100-06. Web.
- Simcharoen, Achara. et al. “Female Tiger Panthera Tigris Home Range Size and Prey Abundance: Important Metrics for Management.” ORYX3 (2014): 370-77. Web.
- Soh, Yi Hui, Luis Roman Carrasco, Dale G. Miquelle, Jinsong Jiang, Jun Yang, Emma J. Stokes, Jirong Tang, Aili Kang, Peiqi Liu, and Madhu Rao. “Spatial Correlates of Livestock Depredation by Amur Tigers in Hunchun, China: Relevance of Prey Density and Implications for Protected Area Management.” Biological Conservation169 (2014): 117-27. Web.
- “Solutions.” Save Tigers Now. World Wildlife Fund. < http://www.savetigersnow.org/solutions>. Accessed 21 February 2015.
- “The Siberian Tiger Project: Managing Tiger-Human Conflicts.” WCS Russia. Wildlife Conservation Society, 2008. Web. 21 Feb. 2015.