The ornamental design for shellfish gauges, as shown.
FIG. 1 is a front elevation view of a first embodiment of the shellfish
gauge; the rear elevation view is a mirror image of the front, and
therefore is not shown.
FIG. 2 is a right elevation view of a first embodiment of the shellfish
gauge; the left elevation view is a mirror image of the right, and
therefore is not shown.
FIG. 3 is a top view of a first embodiment of the shellfish gauge; and
FIG. 4 is a bottom view of a first embodiment of the shellfish gauge.