The Whale Kingdom Quest by Ming Wei
A completely original look at a post-apocalyptic world from the perspective of the sea life that survived. The world under the sea is as disparate and conflicted as the human race that once walked the land. Warring factions make tenuous alliances and fight for their right to remain in this new world. The whale Tenby searches for the last remaining humans, but do any remain? And if they do, will he survive long enough to find them?