Armadillos: Those Pesky Varmints in the Road
By Jeff Whitten
According to some published habitat maps, the territory of the nine-banded armadillo stops 50-100 miles southwest of McNairy County, but if you have ever driven down the road and seen their mangled bodies lying there or found your yard dug up, you know the armadillos have already made our county their home.
What are these pesky varmints and where did they come from?
They originally come from South America. Prior to about 1850, they were blocked from moving to America by the Rio Grande River and their numbers were reduced by hunting by native peoples, according to Michigan State University zoologist Joshua Nixon.
These armadillos are not strong swimmers. The dwindling of native peoples and the bringing of them across the Rio Grande as a food source allowed them to be introduced into Texas.
They moved further north and east due to escaping from captivity. For example, the Florida armadillo population originated when a few of the animals escaped from a zoo in
1924 and from a circus in 1936.
The movement of cattle from Texas also spread the armadillos. They often stowed away on railroad cattle cars. They would often escape as the cars were unloaded.
Armadillos reproduce rapidly because they often produce quadruplets and their eggs can be fertilized for up to 14 months.
They live for 20 years.
Northward expansion of the armadillos is only limited by temperature and rainfall.
Because they have very little body fat, they are not good at conserving body heat. Because of this, very cold temperatures are hazardous to them.
They cannot establish stable colonies if the average January temperature is below 28 degrees. McNairy County’s average of about 39 degrees in January makes it warm enough for the armadillos.
In order for them to survive, they also need 15 inches of rain a year. In McNairy County, we average nearly 49 inches annually.
Although at present time, they are confined to the Mid-South and the lower Southeast, they could expand up the east coast as far north as Boston and New York and could occupy the entire west coast.