Can you “build colonies” for native species?

Yes, though you need to know what sort of nesting sites they like, and what sources of food they need. Many native bees need certain plants to get the nutritional profile they are adapted for, and don’t do so well on nothing but dandelions and typical ornamental flowers. They also need food sources throughout their active time.

For mason and leaf cutter bees, a box sheltered from rain and filled with Japanese knotweed tubes (don’t grow it yourself, it’s highly invasive) works well for “I like seeing solitary bees around, but want minimum efforts”. There are tons of videos you can find on the subject.

Drilling various sized holes in wood blocks also often works. The nice thing about “solitary” bees (which are often quite communal), is they don’t have much of a drive to defend a nest, and would much rather fly away than bite/poke you. I’ve walked alfalfa fields full of them, and while the loud buzzing was a bit disconcerting, they couldn’t care less about me. Leafcutter bees are used for alfalfa because they don’t mind how alfalfa flowers work mechanically. European Honeybees will just chew through the base of the flower to get the nectar, avoiding pollination.

For other bees, there is highly likely to be a native bee enthusiast group in your local area that can give guidance on native flower mixes and possible setups for habitat.

Here in western Oregon, the hazelnut orchards on the sandy soil near rivers have actually become a great nesting place for multiple species of beautiful green metallic “sweat” bees: https://blogs.oregonstate.edu/gardenecologylab/2017/11/13/po...

They like the semi-compacted neutral to slightly alkaline sandy soil that’s clear of weeds, hence a long term orchard is perfect, especially as we’ve moved to softer insecticide chemistries that generally preserve beneficial insects. Offhand I think I start seeing them filling the ground with little holes in may when I start monitoring for Filbertworm moths.

And don’t forget bumblebees. While it’s a hated introduced weed for growers, it turns out that Sharppoint Fluvellen in the fescue grass fields is loved by bumblebees because it happily continues to flower in the late summer/fall when everything else has dried up or run it’s course.

> Japanese knotweed tubes (don’t grow it yourself, it’s highly invasive)

Last year I was lamenting to a neighbor that bamboo doesn't survive the harsh winters where we live. He disputed that.

"There's some growing down the road, next to the ditch," he said. "It comes back every year. It's everywhere."

I was wondering what the heck he was talking about and then I realized it was Japanese knotweed. The segmented branches do look like thin bamboo, and he claimed that at one time it was sold at the local garden center as "bamboo."

Most of the native bees/wasps/flies that are important for pollination are solitary, but you can still help them with nesting areas.

Mason bees can be relatively easy: drill some small holes in a post and let it be. You can also get way more complicated with it.

https://colinpurrington.com/2019/05/guide-to-diy-mason-bee-h...

Bumblebee make nests for breeding, you can sometimes find nests in birdhouses or in gaps of buildings, but they apparently usually go for old mouse burrows. I've seen guides similar to the following, but covering a nest of dried grass with a clay pot, with a buried hose connecting the inside of the nest to the outside.

https://www.ars.usda.gov/ARSUserFiles/20800500/BumbleBeeRear...

Planting native flowers and shrubs can also provide habitat for many insects.

You just need to supply the native plants they prefer to pollinate, they’ll do the rest. If you’re wondering about whether you can harvest honey from them, I don’t think so. Most native pollinator species don’t produce honey.

Bumblebees do produce a kind of honey, but it’s much thinner and less concentrated than proper honey (which has had most of the water evaporated off by the wing beats of the bees).

A thousand years of effort might be able to "domesticate" the bumblebee and make it produce something akin to usable amounts of honey - but unlikely to be worth it.

Someone domesticated foxes in 20 years https://en.wikipedia.org/wiki/Domesticated_silver_fox , so perhaps it's possible to domesticate bumblebee in a few decades - but unlikely to be worth it.

Bumblebees are being "domesticated" to some extent, for pollinating greenhouses, but they're used as labor animals rather than food.