The eggs are covered in a jelly which covers them all. This jelly gives the eggs many advanages!
It sticks them together and prevents their being swept away by a current or eaten by predators. It also protects them from mechanical injury (a rock falling for instance), from drying up and it is also believed it may protect them attacks by fungi and bacteria.
Keeping eggs safe is important for frogs – if the eggs perish then their mating was for nothing!