I don't know this term you used, the “cloche de verre”, but I assume you mean that putting a glass cover on this and then assuming you can resolve all the issues within the cover is the issue.
Each of these populations occupies a range, a historical range, a geographical area where it has existed. The scientific assessment has been about what is required to recover those populations within their historical range, taking into account human disturbance. There are habitat variables—the loss of habitat—and predator variables at play, and also the level of reproductive success.
All of those things were taken into account in assessing the impacts on the population. The proposal to advance an emergency order is one step towards recovering the population, but it is not the only measure that is required for their recovery.