Stinking lazy aliens.. (migration.. or lack thereof)

Psycho0124 · Space Emperor Joined: Apr 17, 2010

Well, rather than my usual mass-genocide playstyle; eradicating all other species in the universe and terraforming all colonies to suit my populace,
this time around I wanted to be a little less genocidal about my conquest of the universe and simply 'liberate' these poor downtrodden aliens from their tyrannical governments (and add them to mine of course Twisted Evil

).

I've acquired all the alien populations I need to allow me to un-dome all of my colonies (even the pesky 'None' atmosphere!). I figured that once a world filled up, the overflow would begin migrating to worlds appropriate to their atmosphere requirements and I could scrap the non-breathers and undome. This didn't seem to happen though. Nobody ever showed up at other worlds. The excess population growth was simply wasted each turn.
Next, I tried building a small fleet of Pop transports and setting them to Minister control, hoping they would sort out the details and disperse the populations as needed (Balance Mod v1.19h, known for its great AI). They fiddled around a little with skimming off excess population but never did much to sort things out.

I've seen breather population show up at domed colonies before, but only with a treaty with another empire. It's a "Humans vs AI" match so treaties are out of the question unfortunately..

So aside from manually (and quite tediously (isn't tedium what ministers are for?)) placing populations where they belong, is there any way to sort everyone out to the correct planet types or should I just exterminate them all and go for terraformers?

Thanks for any ideas you could offer!

Dark_Lizerd · Space Emperor Joined: Jun 12, 2008

It would be nice if there was a feature where:
Hostelworlds: pop would move to better places...
Non-breathers would move to preferred worlds...

Artful_Bodger · Space Emperor Joined: Aug 23, 2009

Aliens don't migrate ?

They won't go somewhere at all if the existing population is excessive, even if the current residents breath the wrong atmosphere.
If you have colonised those worlds with your own & have a lot of your own migration going on, the original population may be too high.

First try, if you have a tiny non breather world with lots of your people on it next to a populated breather world, move/scrap the tiny pop and see if the neigbours arrive.

The underlying situation is more complex & I only partially understand it.

I suspect that unless you get a high enough local population, something like migration% * population > 1M ( i.e. min population to colonise), then nothing ever happens.
It may even be multiples of this. If you fill up e.g. a tiny world with them, that may not be enough to trigger migration from that world.

There is a racial assimilation %, if your lot are a touch Xenophobic, that might discourage things. They may not do so if you are at war with their home race too or are angry, not sure on these though.

An AI population minister exists, but it just scraps existing non-breathers once breathers arrive, unless there is a large number of existing inhabitants, when it won't bother. Try both population and transport ministers on. I'm guessing the latter just tops up existing populations, but doesn't change their composition.

There is also a range effect in play.

If you capture a big enough population (e.g. an intact enemy homeworld), and have the pop minister on, it will seed colonies it breaths, usually near to it (that tiny outpost on the other side of your empire just won't go). You get the auto pop scrapping messages at the end of turn confirming.

I have done this & confirm it happens in BM 19i/h. (Never used the transport minister though.)

If you look at the race stats on your own homeworld you will see that the migration% is less than the birth rate %. The mechanism which wastes population is right there from turn 1 with your own people.

I adopt an early game tactic of setting up a couple of transports to skim off the excess homeworld pop & send it to my nearest breathable colony.
This aviods homeworld population waste & ups the %s on the new world so it starts to make a difference migration wise.

May I suggest this tactic for your aliens, select one large (or greater) planet , collect the bulk of them there & get the pop up to ~1B ?

That should trigger migration. If you are an oxy breather, have some captured co2 alien colonies, also swap out the co2 on h2, ch4 etc worlds for your own people & collect all the co2 on that large, optimal world with all the happiness & medlab you can give it. They should then breed at 10-20% and in a while start wandering off on their own.

This ain't quick, if the war proviso I mooted above exists, you may even have to toast the home empire first.

Ender · Space Emperor Joined: Apr 18, 2008

Artful_Bodger, you are basically right, but if you want to understand how exactly migration works then look into Settings.txt and start a game with 10 homeworlds to see what the influence of the planet condition is like.