Forum:Special Summon a Ritual Monster

If I have Raging Eria, an additional WATER monster on my side of the field, as well as Fortress Whale in my hand, can I use Raging Eria's effect to Special Summon Fortress Whale?

For my own clarification if the text of a Ritual Monster says "This monster can only be Ritual Summoned with the Ritual Spell Card..." does that mean that is the only possible method of summoning that card or are other special summoning options still available?