
The "thing" at the lake is really a freshwater invertebrate called moss animals.
Each "blob" is a colony of millions of tiny organisms called zooids. The colony exudes a protective gelatinous material that makes it resemble a big ball of jelly. They eat the microscopic plants and stuff that is floating in the water. They clean the water. When they dry up, they turn to a paper like substance that crumbles and disintegrates. They cause no harm and their presence signifies good water quality.
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