Much of the original forest cover on Madagascar has been destroyed primarily as a result of _____.
burning for agricultural purposes
What is the cause of the red color of the waters about Madagascar?
soil that has washed into the ocean
From 1930 to 1939 fire ants spread inland about 60 miles from their point of introduction in Mobile, Alabama. What was the cause of their spread over this distance?
a natural spread
From 1940 to 1970 fire ants spread through many southern states, sometimes at a rate of 100 miles in a year. What was the cause of their spread over this distance?
being transported along with plants and soil
In 1958 federal law restricted the movement of soil and plants from areas where fire ants were established. Why was this law unsuccessful in stopping the spread of fire ant colonies?
People were unaware of the federal law and, when they moved, transported plants bearing fire ant colonies; a single mated queen can be transported without being noticed; and many states thought to be free of fire ant colonies already had them.
Techniques used, or are being considered for use, in controlling the spread of fire ants include _____.
setting baits that kill the queen when they are carried back to the nest, applying chemical powders that kill the colony, introducing a protist to infect the fire ant queen and her eggs, and introducing a fly that lays eggs in fire ants so that the eggs will hatch into larvae that eat their way into the ants' heads, which will then fall off
As of the time of the writing of Activity: Introduced Species: Fire Ants, fire ants have caused about _____ deaths in the United States.
( As of the time of the writing of Activity: Introduced Species: Fire Ants, fire ants have caused about 20 deaths in the United States.)
One of the most severe consequences of habitat degradation is the _____ of a population.
A sink habitat is where a subpopulation's death rate is _____.
greater than its reproductive rate