I claim the ornamental design for a multilevel bird bath, as shown and described.
FIG. 1 is a top perspective of a multilevel bird bath;
FIG. 2 is a top plan view thereof;
FIG. 3 is a bottom view thereof;
FIG. 4 is a top perspective sectional view of the multilevel bird bath taken from along the 4-4 line indicated in FIG. 1;
FIG. 5 is a sectional elevation view of the multilevel bird bath taken from the 5-5 line indicated in FIG. 2;
FIG. 6 is the side view of the multilevel bird bath; and,
FIG. 7 is an in-use enlarged sectional elevation view of the multilevel bird bath taken from the 5-5 line indicated in FIG. 2.
All matter from the bottom floor of the invention depicted in unclaimed broken line, up to the start of claimed solid line, throughout all the drawings, is not claimed. The broken line depiction of birds in FIG. 7 is for illustrative purposes only and does not form part of the claimed design.