Closure of steel plants in the 1970s caused many residents to be unemployed. Their departure caused the failure of retail and service businesses that had been dependent on steel workers. Another way of looking at it is to say lack of diversification caused the collapse. Youngstown had depended on a single industry -- steel.
The Bubonic Plague (a.k.a The Black Plague) caused a dramatic decline in the population of Europe in the 1300s.
According to census.gov, the 2007 ACS population estimate for Youngstown, Ohio, is 73,818.
Diseases brought from Europe for which they had no immunity.
The population of Summerfield Florida in 2002 is 19,410. Where as in 2010 it was reported that the population had declined to 14,487. The factors are unknown as to what caused the decline.
Disease brought over by explorers
Economis decline is what caused the naval superiority to decline then
The African skimmer is listed as "Near Threatened", not endangered. The decline in population seems to have been arrested now, and there is some resurgance in population. Habitat loss caused the initial decline.
The decline of moose population followed sooner or later by a decline in the wolves population because the is less for the wolves.
The decline of the primary sector is caused due to the fact of less raw materials and a growth in population so more goods and services need to the sold. also farm lands are decreasing and industry is increasing.
there would be to many fish romaing the sea
There was a decline in the population as a result of the war.
The decline of Zimbabwe was from poor management and political corruption,