The increase in the number of black snails can. best be explained by

As far as I know about black snails is the fact that the Black Mystery belongs to the genus Pomacea,  Ampullariidae family. This family is also often called Apple Snail, and it contains a nearly 120 different species of snails. I know that increase in the number of black snails can best be explained by the high teperature in which black snails are. It's the main reason of their reproduction.