If you decide to collect Mussels visit small coves away from settlements. Wait for low tide and if they are present many will be accessible attached to the shoreline. Collecting is a common practice locally and some people travel to beaches ready for a cook-up. It just takes a small fire, a large pot and you'd boil them in sea water. When the shells open they are cooked. The downside of collecting Mussels is that some will have tiny black pearls which are crunchy. Don't collect them when the surf is up; no need to fall into the ocean.
Enjoy getting out in Newfoundland. The thousands of miles of coastline offers much adventure.