Every year in the foothill streams of California's Sierra Nevada mountains, young, wild salmon emerge from rock nests, and at different times, begin migration down the river to the Central Valley and ultimately the Pacific Ocean. Their strategies are to leave at different sizes and times during the spring. These small fish, some very small, face many challenges and obstacles as they battle to reach the sea. Their life's mission: get big and return to their birthplace to mate. But which way out gets them home? Based on one of the author's scientific publications, and illustrated by her, this rhyming picture book for children explains the juvenile salmon journey and answers the question of which out-migration strategy works. Informative and entertaining, Who's Coming Home? introduces kids to science and how to answer questions about nature using it.