no but he can end refugee benefits - i.e. put a cap on refugee benefits to 2-3 years and then none. there is no reason why any refugee should be getting benefits for life.
if i were pierre, id cap refugee #s to 15k per year, cap benefits to 2 yrs, and thats it. curb demand for our country's social net and people will not come here for it.
Refugees get benefits for 1 year, except for those who qualify for special programs who get benefits for 2 years. They can make a demand for "normal" welfare afterwards.
We had relatively low numbers of refugees before the 1980s; Trudeau (the dad) went all in from 80 to 84, mostly with refugees from Vietnam, Laos and Cambodia. Mulroney was even more welcoming than both Trudeaus.
Temporarily limiting the possibility for refugees to apply for permanent residence would be a decent solution.