canada has almost full control of immigration because of the ocean and the us as buffers, and because it is very difficult to be undocumented and access health care or work. it takes in more legal immigrants/refugees per capita than the us does, but it has almost zero illegal immigration.
historically canada has almost no issues with either illegal immigration or refugee claims from the us. it's been the opposite with small numbers of folks flying to canada on a visa to sneak into the us because they can't get a us visa.
but since trump was elected asylum seekers and illegal immigrants already in the us have started walking over the border into canada.
this is now a problem in canada. there is a tent city at a quebec border crossing to handle the flow. the locals there and folks at the manitoba border are fed up with it.
to contest this the canadian government is trying to get information warning prospective refugee claimants that they are likely going to be deported home. unofficially, this is to encourage them to go illegal and stay in the states.