Usually they will be part of a mass migration process.

We should also think about the problems of the world as a whole, which cause mass migration in the first place.

Other factors such as mass migration out of China must be taken into account.

There were three factors that led to the 'age of mass migration'.

But officials played down the threat of a mass migration, saying the situation was under control and had improved since last year.

Finally, they, too, become discouraged and join the mass migration out of the city.

This has led to mass migration from the rural areas to the metropolitan area.

The mass migration, feared from the beginning, is happening now, daily.

At the turn of the 20th century, many people left the region and joined the mass migration to the Americas.

The violence was the trigger for a mass migration to the suburbs.

How many of them will seek to join the mass migration is unknown.

In a country of 900 million peasants, the last thing China can afford is a mass migration to the cities.

"I'm convinced this new century will see a mass migration off of the Earth into free space.

The spread of the disease was helped by modern transportation and mass migrations.

And mass migration means that there must have been masses of these insects around.

He was 28, born before the mass migration from the island to New York began.

But mass migrations are not expected, mainly because of cultural and language difficulties.

It was the largest mass migration in modern times.

In the early 1970s, there was a mass migration to this area from the Guntur district.

The war was devastating to the state's economy and forcing mass migrations.

China is now experiencing the largest mass migration of people from the countryside to the city in history.

At the age of 14, he joined the mass migration to North America.

Mass migration had almost overnight made blacks America's most urban ethnic group.

In the 1980's, spring break meant mass migrations of party animals to Florida spots.

Mass migration from Asia has reinvigorated the street scene in recent years.