Answer:
The marsh habitat is already suffering due to overpopulation of snakes
Step-by-step explanation:
The above is the statement that best expresses the main idea of the excerpt.
From the excerpt, we discover that pythons are taking over the habitat. When the python was caught by Hill and autopsy was taken, what the python feeds on was discovered.
The snake feeds on other animals like deer. This reveals that the other animals in that habitat are already endangered. They are suffering due to overpopulation of snakes.