I often see that we do things from the top down, rather from the bottom up. You cannot build an ecco system without the base of the pyramid being already in place.
For instance,
There is a butterfly that all but died out, think it was one of the blues, and nobody could figure out why. One young man sat out for months studying the last remaining few, and discovered that it relied on a symbiotic relationship with one particular variety of red ant, which was also dying out as they needed a very particular length of grass to survive, and modern farm practice had altered that detail by stopping grazing to rewild the area, causing the grass to grow too long...(or was it the other way round? I forget the exact details).....anyway, the height of the grass was critical for the ants survival, and the ants were critical for the butterflies survival. So just simply reintroducing the butterflies from elsewhere (top down) would have been pointless without the correct habitat, and ant species being conserved first. (Bottom up)
But of course human ego wants to focus on the macro project for fame and glory, rather than focusing on the micro projects that criticaly support everything above it.
I too want to be able to sleep in my hammock safely without a mammoth or t rex wandering through the campsite thank you very much!