The asset includes two shaders, one for birds and butterflies, the second for fish. I did not combine the shaders into one, because the animation in the shaders is not the same.
Important! You must set the Render Queue to more than 2500 if you are using the Forward rendering path (please read "Performance Tuning" carefully).
Bird Flapping
Flapping Speed - the speed of flapping wings.
Flapping Y Power - the power of flapping wings along the Y axis.
Flapping Y Offset - offset of flapping wings along the Y axis.
Flapping X Power - the power of flapping wings along the X axis.
Flapping X Offset - offset of flapping wings along the X axis.
Flapping X Center Indent - Indent in the center along the X axis.
Flapping Z Power - the power of flapping wings along the Z axis.
Wave Y - the general oscillation of the object along the Y axis.
Wave Y Speed - the speed of the oscillation.
Butterfly - enable butterfly animation mode.
Swimming Fish
Swimming Power - the general power of swimming.
Swimming Scale - the general wavelength.
Swimming Speed - the general swimming speed.
Wave Body - wave amplitude, XZ axis.
Wobble - swing locally along the YZ axis.
Wave Y - the general oscillation of the object along the Y axis.
Wave Y Speed - the speed of the oscillation.
Script Control [HideInInspector] - change the speed and direction of the animation through a script. This parameter is used optionally. For more details see the shark script from the "Fish Boids Danger" example.