Do sharks eat gray whales?

No. Orca's are the only known natural predator of the gray whale. Groups of Orca's can easily kill a mid sized gray whale. Full grown adults are too big for even a group of Orca's to kill. But, babies are especially vulnerable. The Gray Whales give birth to their young in shallow lagoon waters. This is done to protect the newborn from predators like sharks and orcas