September is a great time to visit because we actually get the best of our weather in August & September. The thick July fog is usually gone when September rolls around.

Cape St Mary's is open to the public. No reservation required. There is a visitor's center with hours, but you can walk the path to see the birds without going to the visitor center. We were there in July, but I think anytime from June thru August would be a good time to go. See thousands of Northern Gannets fairly close, but a good zoom lens makes for better pics.

The 92 is better, but the 100 is fine. I suggest going down one way and back the other so you see different things.

Hi Edward, You may not see many puffins at cape St. Mary's. The ecological reserve is fantastic to see gannets in particular. There are other birds there as well during the spring/summer. When we went at the end of August, it was all Gannets. I would recommend going for sure if you have time. If it's Puffins you are after in particular, then the closest spot with rookeries is Witless Bay just south of St. John's. I have not been myself so don't know if you can access them from the land too much. There are "Puffin Boat Tours" available though that will likely give you a good look. You can find puffins here an there along the coast but not the large rookeries as in Witless bay. If you are willing to go further, then Elliston is a really good place to go. (read my review and see photo's). Once again, we were at the tail end of Puffin season. At the end of August and the beginning of September, they head out to sea where they spend the Winter. They come back to reclaim their burrows in the spring/early summer. A friend was there in July and said there were lots of them so close he had to back up a bit to take pictures. I can't post a link but go to the newfoundlandlabrador website (then) ThingsToDo (then) BirdWatching Hope this helps.