We claim the ornamental design for a “rudder for electric trolling motor,” as shown and described.
FIG. 1 is a right side perspective view of our new rudder design.
FIG. 2 is a left side perspective view thereof.
FIG. 3 is a right side perspective exploded view; and,
FIG. 4 is a reduced right side view of the rudder shown attached to a trolling motor. The trolling motor shown with broken lines, illustrates an exemplary environment in which the rudder resides and forms no part of the claimed design.