Can you be more specific what kind of scientists and positions you are hiring and filled?

Postdoctoral fellows position always receive huge number of applications, but these are all temporary positions.   Tenure professorships also receive a lot of applications,  but i doubt you have that many unfilled positions.  Some industries in Canada hire PhDs And I doubt you have that many applications from foreign scientists if you are hiring for a industrial position. Unless of course when you say scientists, you are using the term loosely.