The ornamental design for a boatventilation hatch cover, as shown and described.
FIG. 1 is a front perspective view of the boat ventilation hatch cover of the present invention;
FIG. 2 is a front view of the boat ventilation hatch cover of FIG. 1;
FIG. 3 is a back view of the boat ventilation hatch cover of FIG. 1;
FIG. 4 is a side view in elevation of the boat ventilation hatch cover of FIG. 1 as seen from the right side of FIG. 2;
FIG. 5 is a top plan view of the boat ventilation hatch cover of FIG. 1; and,
FIG. 6 is a side view of the boat ventilation hatch cover of FIG. 1.
The broken lines in FIGS. 1-4 stitching and represent claimed subject matter. The broken lines showing a portion of a boat in FIG. 6 is for the purpose of illustrating the environment in which the article resides and forms no part of the claimed design.