It’s the over-fishing of their main food source.
They are coming in closer to shore because they have no great schools of fish to consume..............
It is not over fishing of their food source.
It is because the government protected the north Atlantic Gray seal.
They were endangered. Now there are tens of thousands of them. The Great Whites like to eat the seals. They are all over Monomoy Island just south Chatham, MA at the elbow of Cape Cod.