Indian Elephant Population in Thailand
- 1 Problem definition
- 2 Method
- 3 Model
- 3.1 Model variables
- 3.1.1 Population
- 3.1.2 Increase
- 3.1.3 Decrease
- 3.1.4 Natality
- 3.1.5 Fertility
- 3.1.6 Ratio of females in reproductive age
- 3.1.7 Ratio of females
- 3.1.8 Government regulation
- 3.1.9 Mortality
- 3.1.10 Average lifespan
- 3.1.11 Unnatural deaths
- 3.1.12 Deaths by improper handling ratio
- 3.1.13 Poaching ratio
- 3.1.14 Deforestation ratio
- 3.1 Model variables
- 4 Results
- 5 Conclusion
- 6 Code
- 7 References
During the course of the 20th century, the population of indian elephants has decreased drastically, mostly due to a significant reduction of elephants' natural habitat, as well as decrease in utilization of elephants in logging industry and shift to a role of a tourist attraction. This model showcases the evolution of elephants' population in Thailand for upcoming 100 years.
The vensim modelling tool was selected for the purpose of this simulation.
Number of elephants in Thailand. Starting value is 8900 . This is the variable that we are examining.
Number of elephants that are born
Number of elephants that have died
Ratio of newly born elephants to elephant population. Amount of newborn elephants equals fertility multiplied by number of females in reproductive age divided by 40*2 (number of reproductive years, multiplied by 2 as elephants pregnancy takes 22-24 months).  We then multiply by Governement regualtion ratio.
=((Fertility*((Ratio of females*Population)*Ratio of females in reproductive age)/80)*Government regulations)/Population
Amount of calves a female is able to have during her reproductive lifespan. 40% of elephants' population lives in wilderness and the fertility is not affected by stress therefore a wild female is able to have 10 calves, and semi-domesticated female is able to have 7 calves during her life.
Ratio of females in reproductive age
Elephant female can have calves during her 15 to 50 years. 
Ratio of females
Ratio of females on elephants' population
Index of government regulations <0;1>, 1 means no government regulation
Ratio of dead elephants on the elephants' population.
=((Population/Average lifespan) + Unnatural deaths)/Population
Number of deaths that do not happen naturally.
=((Deaths by improper handling ratio*Population)+(Poaching ratio*Population))*Government regulations + Population*Deforestation ratio
Deaths by improper handling ratio
Ratio of deaths that happen due to unhuman behavior towards elephants and conditions they have to live in.
Ratio of deaths that happen because of elephants being hunted either for skin, tusks or to capture young calve.
Ratio of deforastation in Thailand, this has a close correlation to number of elephants as this the major factor affecting the population. 
In this simulation I created a functional model representing the evolution of elephants' population in Thailand. The results show continuous decrease over the course of following 100 years. However there is a room for improvements, like parameter deforestation ratio because nowadays the problem of deforestation is gaining on significance in general public eyes and this might lead into deforestation ratio decrease and potentially lead into elephants' population growth. In addition, also the pressure from general public as well as organizations like WWF might lead into more strict government regulations.
- ROGER, L. The elephant situation in Thailand and a plea for co-operation[online]. Available from: http://www.fao.org/3/ad031e/ad031e0r.htm
- Elephant Reproduction [online]. Available from: https://www.elephant-world.com/elephant-reproduction/
- Longevity and causes of death [online]. Available from: https://seaworld.org/animals/all-about/elephants/longevity/
- Deforestation statistics for Thailand [online]. Available from: https://rainforests.mongabay.com/deforestation/archive/Thailand.htm