There is a good article by economist Judith Sloan about the lack of economic benefits of migration:
http://www.theaustralian.com.au/opinion/columnists/judith-sloan/bigimmigration-fan-club-is-devoted-to-growth-myths/news-story/63bd150133321ba70dd3fba2cede1b67

“And what the best quality studies show is that the economic benefits of immigration are zero or slightly positive, with most of the gains being captured by the migrants themselves.
Employers and incumbent workers with complementary skills gain, but incumbent workers who have similar profiles to new migrants miss out in terms of employment prospects and wages.
Then there is the myth about immigration being useful in the context of an ageing society. The Productivity Commission has made the point at least three times that the impact of immigration on the demographic profile of Australia is minimal. After all, migrants themselves age.
What does surprise in the context of the immigration debate in Australia is the now active role being played by the Reserve Bank. After all, the Reserve Bank really does only one thing and that is to set the cash rate on a monthly basis, although it has January off (how last century). One wonders what the more than 1300 bank staff members do all day.
The governor and now an assistant governor of the bank have become active players in promoting high rates of immigration.
While accepting that high population growth — note that immigration accounts for more than half of our population growth — is contributing to high house prices, newly appointed governor Philip Lowe recently expressed the view that “our immigration program I see as a source of national strength. To give that advantage up just so that we can take some pressure off housing prices, I find kind of problematic.”

     This really is an extraordinary thing to say. With his high salary, he will be able to help his children into the housing market. But to dismiss the pressure of high and rising house prices on large numbers of people is surely an inappropriate remark by a senior official. To be clear: “ ... a source of national strength” is a non-specific, non-analytical and lazy rationale for our immigration program.”

     This article opens by referring to the book by Douglas Murray, The Strange Death of Europe:
https://www.amazon.com/Strange-Death-Europe-Immigration-Identity/dp/1472942248
     This book argues that uncontrolled immigration was something of an accident, with there being an initial demand for labour, which then, by a series of events, spiralled out of control. That view is completely wrong, and anyone wanting an alternative view of how the West was undermined by immigration can explore many sites:
http://www.theoccidentalobserver.net
http://www.vdare.com

     We have been arguing against the “accident” view of history at this site since the days of Eric Butler.
     A sorry tale, but true –  sleepers get displaced.