Realistic population numbers for an island nation

Specifically a South Pacific (loose) equivalent of Wakanda, which primarily supports itself through farming and fishing.

I think we need to know a bit more about the geology (high island like Tahiti or Hawaii? Atoll like Mili or Eniwetok?), size, soils and climate (wet like the Micronesias, or dry like Kiritimati?). In such a subsistence economy, the availability of resources is likely to be the main constraint on population size.

In short, it depends. Is a big island? Bigger or smaller than England? How fertile is the soil? How much fish can they catch? What kind of crops can they grow?

Food is the number 1 limiting factor in population growth. If you can't feed your peeps then you loose them.

^^ This. As well as size of the island. Even unusually large islands like the Hawaiian Archipelago don't support a very large population easily owing to limited space.

And most Pacific islands or images and such thereof are much much smaller than that.

And you'll want to take colonialism and immigration into account: if your island nation is/was a plantation economy, or a strategic military base like Guam and American Samoa, then there'd be a lot of foreign traffic coming in, which would bring lots of settlers and migrant workers. Though I guess the latter wouldn't suit your premise.

Edited by eagleoftheninth on Dec 9th 2020 at 12:23:10 PM

It's also good to consider that Australia is also an island (depending on who you ask) and so is England or Japan.

If the nation is Wakanda though, and completely isolated, it would be hard to justify with say, Hawaii. In fact, i'd say the ideal Wakanda already exists and it's called The Americas. You'd have all the isolation you'd need to have a completely independent civilization yet it's big enough that you wouldn't be dependent on unnatural luck to survive thousands of years.

Because in our world, civilization survived through trade and contact. Individual civilization rose and fell, and much knowledge was lost. Yet, through trade these ideas carried far and wide and so outlived and outspread their inventors.

As to why the Americas never became a Wakanda is hard to say. Some blame it on lack of easy trade routes like the Silk Road.

Or the fact that, you know, nations don't really work like they do in the Marvel Universe.

This list of islands and their population density will give you an idea of what is realistic. A very rough average for a well populated island appears to be somewhere in the low thousands per sq. km.

Edited by DeMarquis on Dec 9th 2020 at 11:15:17 AM

If instead than a fishing/farming subsistence economy, your nation had a well-developed service economy, whether revolving around tourism, transport/logistics or even finance, then it could potentially support a larger population than its own resources would've allowed, clustered in dense urban centres and importing its needs from elsewhere.

^ Which is largely what a lot of island nations, provinces, states and prefectures do. Hawaii is terminally dependent on tourism and its strategic military location as the crossroads of the Pacific. If that ever were to fail, the population there would plummet in a hurry. (Or at least plummet into poverty.)

A tourist or service industry is hard to square with a Wakanda though.

TBH my first thought with this thread was "if it's wakanda it's inherently unrealistic so just go with whatever you think is needed".

But if the goal is to have a semi-realistic, isolated, industrial or post-industrial nation you more or less need something continent-sized (if on the smaller end of a continent to count as an island). because to be isolated it would have to be self-sufficient in resources and have plenty of space to farm and mine from in order to support dense cities with high technology.

Edited by devak on Dec 10th 2020 at 9:06:19 PM

Eh, depends. Java is hardly continent-sized but had enough natural resources and a friendly enough climate to support a massive population on wet-rice agriculture. Today it has upwards of 140 million people and is a net exporter of migrants. Of course, a lot of the historical tech it needed to develop that way came from extensive trade contact with other Asian powers and eventually the Europeans, which a small Pacific island nation might not enjoy.

Anyway, to give a straightforward answer to the OP: I'd put it from the tens of thousands to the low hundreds of thousands.

Java has also friendly enough soils.

If my understanding of this stuff is correct, the difference between the relatively useless soils Hawaiian hotspot volcanoes and coral reefs deliver and the kind of soils that arc volcanoes such as these in Java deliver has a large impact on agricultural productivity. Thus Java can support a larger population per area than Hawaii or Tuvalu.

Plus a fairly predictable supply of fresh water from the monsoon system and lots of highlands creating watersheds that channel all that water across many fertile river valleys. Smaller Pacific atolls, in contrast, rely on a shallow lens aquifer for their freshwater (which sometimes gets contaminated by the saltwater layer underneath).

Basalt soils are very productive for farming. A big reason why for many crops is they are iron-rich because basalt has a high proportion of iron in it. (The big reason why basaltic rocks can be magnetic.) Hawaiian and Pacific Island soils are less than ideal because the soil isn't very deep, it can be easily exhausted by overfarming. Contrast that with the Black Earth Belt of the Ukraine and Western Russia and the breadbasket regions of North America in the Great Plains which have deep fertile soils well suited for massive scale farming.

But then again, basalt is not the reason why Hawaiian/Pacific Island soils aren't very deep. Basaltic soils exist in many places on Earth including some regions with large scale farming operations. The lack of depth is caused by the tropical climate and foliage. Most tropical biomes have surprisingly poor soil quality relative to places like Kansas. It stays shallow due to excessive consumption by foliage and erosion by rain, both are very voluminous in the Hawaiian Islands and on numerous other Pacific islands. The same reason why you have to slash and burn the Amazon or the Congo for farming as opposed to just tilling and seeding like you do in the prairies.

Edited by MajorTom on Dec 11th 2020 at 7:05:50 AM

Well, I did say "useless soils" and not "useless basalt soils" and besides, the other islands such as Java also have a tropical climate. Nah, the type and chemistry of volcanism work better as an explanation.

BTW, pinging ~ecss.

Basalt or basaltic products (ash, scoria, etc.) are a consideration when talking about Pacific Islands. Geologically, there's almost no other rock across most of the oceanic basin. There's very little andesite or dacite and almost nothing like granite. Excepting islands that are continental fragments geologically speaking (Indonesia, New Guinea, Philippines, etc.), everything else is made of basalt for the most part. The stuff that isn't is typically either locally formed limestones like seen in a couple Hawaiian atolls or coral based products.

All of the inhabited Hawaiian Islands for example are almost purely basalt with the older of those islands like Oahu having a minor bit of coral sand on its beaches.

You can't proclaim "useless Hawaiian soils" without making that a factor. Local geology can be a factor in the quality and depth of soils.

I wouldn't really classify New Guneia as a continental fragment as much like the British Channel the Torres Straight is just a temporarily flooded continental lowland. During the last glacial maximum Australia, New Guinea and Tasmania all formed a single landmass sometimes referred to as Sahul.

That depends on your definition. Because Beringia (Bering Strait land bridge) no longer exists and we don't classify easternmost Russia as part of North America partly as a result. Which is weirder when you realize tectonically, the North American Plate doesn't end until the western reaches of the Chersky Range in Eastern Russia.

Which means if you really stretch the definition of continent, we never truly left the last supercontinent cycle much. Because if continuous land or temporarily submerged land are used as the basis for continents then there are only 2-3 continents on Earth presently. Africa has a continuous land bridge to Eurasia via the Sinai which connects to North America via Beringia which connects to South America via Panama. The only truly separate continents from that would be Antarctica but given the land bridge between Australia and Southeast Asia isn't really existent anymore that can be considered separate as well. Micro-continents or continental fragments would still exist in Zealandia, Greenland, Iceland and Madagascar.

Is the definition of "Continental Fragment" really worth arguing over? Because any second now the Ghost of Diogenes is going to barge in with a plucked chicken.

What?

I admit i laughed way too hard at that.

context:

"According to Diogenes Laërtius, when Plato gave the tongue-in-cheek definition of man as "featherless bipeds," Diogenes plucked a chicken and brought it into Plato's Academy, saying, "Behold! I've brought you a man," and so the Academy added "with broad flat nails" to the definition"

Edited by devak on Dec 15th 2020 at 3:06:35 PM