Let $X$ be a smooth complex manifold with trivial canonical bundle and
$\phi:\; X \mapsto Y$ a proper holomorphic
map which is birational ("birational contraction"),
and $Z= \phi^{-1}(y)$ its fiber in a point $y$.
The variety $Y$ is not assumed to be smooth.
In this case I think that $Z$ is Moishezon.

I would be very grateful for a reference or a simple argument.

Misha