Answer:
The impacts may be seen in population drop, lower birthrates, aging population, lack of qualified labor force, ''brain drain'', etc.
Step-by-step explanation:
The countries that lose their population through migration are having to face big impacts because of it, and all of those impacts are negative and reflect badly in the long run. When a population migrates out of a country it is not just that simple as it has huge implications for the future of the country that losses them.
The demography of a country is usually badly impacted, like in the case with Bulgaria for example, where the country has been constantly having a declining and aging population over the past few decades. The people that are highly educated tend to be the ones in the highest percentage from the ones that move it, meaning that the country losses its future but also its current high-quality labor force. The most talented students and workers too tend to go away, and those are the ones that mostly bring development to the society, so while the country where they go benefits, the country from which they move away stagnates.