In a large, non-metal bowl, combine water, ketchup (or tomato sauce), white vinegar, lemon juice, Worcestershire sauce, juniper berries, diced onions, and salt.

Blend the sauce ingredients well.

Add the caribou ribs to the marinade and ensure they are fully coated.

Cover the bowl and refrigerate to marinate overnight (at least 8 hours).

Preheat the oven to 325°F (160°C).

Remove the ribs from the marinade, letting any excess sauce drip off.

Pat the ribs dry with paper towels.

Sprinkle the ribs generously with fresh ground black pepper.

Place the ribs in a 5-quart roasting pan in a double layer.

Roast the ribs for 1 hour at 325°F (160°C).

Pour the remaining marinade sauce over the ribs.

Increase the oven temperature to 350°F (175°C).

Continue baking until the ribs begin to char slightly on top, approximately 1 1/2 hours.

Turn the ribs over, cover the pan with foil, and bake for another 30 minutes, or until the ribs are tender and the sauce has thickened.

To serve, arrange the ribs on a serving platter.

Serve the remaining sauce in a gravy boat on the side.