Human overpopulation is a concern that traces its roots back to ancient times, but seems to be a subject of debate even today, as part of conversations surrounding climate change and the ever-growing global population. Nowhere are population concerns more poignantly observed than in island nations that present barriers to emigration with limited space and resources. Island nations experience varied rates of population growth with some leveling out around the replacement rate, some declining, and others continuing to grow. The following are the five most populous island nations in the world. (Population estimates are as of 2018.)
Population: 23.69 million
Taiwan is the fifth most populous island nation in the world and the 16th most densely populated nation in the world. Taiwan saw massive population growth in the 20th century, from an estimated 3 million in 1905 to 22 million in 2001. The surge in numbers was seen as a result of high birth rates, low mortality rates, and an influx of migrants from the Chinese mainland following the end of the civil war. Growth rates declined throughout the 21st century with a record low of 0.2 percent in 2010.
4. United Kingdom
Population: 66.57 million
The U.K. is the fourth-most populated island nation in the world, with the highest percentage of its population residing in Southeast England. Though populous, the population growth rate in the U.K. has hovered around and below the replacement rate since 2012. As of 2017, the U.K. is experiencing a 0.6% annual population increase. The wide majority of the population (92.12%) is composed of white English nationals with Asian ethnic groups—primarily Indian, Pakistani, and Bangladeshi—constituting 4.39% of the total population. As of 2018, the UK saw 283,000 immigrants with an intention to stay 12 months or longer. Non-EU migrants comprise the largest portion of UK immigrants, though total migration rates have stabilized since 2016.
Population: 106.5 million
The Republic of the Philippines is the third most populous island nation in the world with a total population of 106.5 million and a 1.5% positive population growth rate as of 2017. The most populous region of the nation is Calbarazon, with a population of 14.4 million. The growth rate of the nation has been a concern as of the 21st century. In 2011, the Philippines government passed “The Responsible Parenthood, Reproductive Health and Population and Development Act of 2011,” in an effort to slow population growth through the availability of sex education, contraceptives, and abortion.
Population: 127.2 million
With more than 38 million inhabitants in the Tokyo area alone, it should be no surprise that Japan is on this list. Tokyo is among the most expensive cities in the world in part because of the scarcity of space. Japan’s population peaked in 2010 at 128 million. However, the population has since declined as the country experiences declining birth rates and virtually no immigration. It is projected that the population will continue to decline by 1 percent per year into the future.
Population: 266.8 million
Indonesia is the most populous island nation in the world. Of the nearly 267 million Indonesian people, 58 percent live on the island of Java. The limited space and substantial population of the island led to national family planning programs starting in 1967 in an effort to slow population growth. The program was successful in raising the contraceptive prevalence rate to 60% and cutting the fertility rate in half (from 5.6 to 2.6 children per woman). However, the population continues to grow on the island nation, and additional efforts are being advocated for expanding the family planning program.