In the early 20th century, “giant sponges” were primarily a focus of the lucrative commercial sponge industry, particularly in the Mediterranean and Caribbean. Species considered giant by fishermen of that era were prized specimens for the bath sponge market, though modern science has since identified even larger sponges in deep, remote waters.
The natural sponge trade flourished in the early 1900s before collapsing due to disease and competition from synthetics. Greek divers migrated to the U.S., establishing major sponge harvesting operations in Florida, especially in Tarpon Springs.
Divers initially used surface-supplied air hoses to reach sponges at greater depths, which was more efficient than harvesting from shallow water. This allowed them to access larger specimens growing in deeper waters.
The Neptune’s Cup sponge (Cliona patera or a similar species) was a large, unique sponge known in the Indo-Pacific region. Overfishing in the late 19th and early 20th centuries led to its near-extinction, and it was considered lost for almost a century.
By the 1930s, the industry was already in decline due to overharvesting. This was made worse by a sponge blight and the introduction of synthetic sponges in the 1950s, which ended the golden age of natural sponge harvesting.


































