I claim the ornamental design for a marine anchor nest, as shown and described.
FIG. 1 is a front left perspective view from above showing my new design for a marine anchor nest in a closed position;
FIG. 2 is a front left perspective view from above of the marine anchor nest of FIG. 1 in an open position;
FIG. 3 is a front right perspective view from above of the marine anchor nest of FIGS. 1-2 in a closed position;
FIG. 4 is a right side view of the marine anchor nest of FIGS. 1-3 in a closed position;
FIG. 5 is a left side view of the marine anchor nest of FIGS. 1-4 in a closed position;
FIG. 6 is a rear view of the marine anchor nest of FIGS. 1-5 in a closed position;
FIG. 7 is a rear right perspective view from below of the marine anchor nest of FIGS. 1-6 in a closed position;
FIG. 8 is a rear right perspective view from below of the marine anchor nest of FIGS. 1-7 in an open position;
FIG. 9 is a bottom view of the marine anchor nest of FIGS. 1-8 in a closed position;
FIG. 10 is a top view of the marine anchor nest of FIGS. 1-9 in a closed position;
FIG. 11 is a front view of the marine anchor nest of FIGS. 1-10 in a closed position; and,
FIG. 12 is a front left perspective in use view from above of the marine anchor nest of FIGS. 1-11 in a closed position; the broken line showing of an exemplar marine anchor forms no part of the claimed design.