Animals are among the first symbols any human race has used. From birth we know that certain animals represent traits that are human, such as courage, wisdom and strength. I would look into Viking, Egyptian, Christian, Native American Legends and Greek/Roman mythos for animal motifs.
Tigers: a symbol of strength, power, energy, passion, ferocity, sensuality, beauty, speed, and wrath.
Panthers: symbolize strength, , adventure, loyalty, triumph, and a spiritual mind or personality.
Lions: courage, power, royalty, dignity, authority, justice, wisdom, and ferocity.
Koi Fish: fortune and luck, perseverance in adversity, and strength of purpose. (Japanese)
Dolphins: gracefulness, playfulness, gentle, harmony, intelligence, friendship, community, and generosity.
Crabs: trust, emotion, protection, regeneration, and transformation.
Shark: calculation, perceptiveness, and instinct.
Dove: peace, hope, love, freedom, promise, maternity, and messenger. (Christian)