I went on this activity for the sole reason of trying different mollusks and not for kayaking. My wife and my 1.5 hr trip to the Ria Formosa Natural Park started with us running to the kiosk since we were slightly late, and I asked the man standing at the kiosk where the tour group was. He said there were only tours at 11:30 and we got there at the 9:30 kayak rental time. Even though they were described as all the same on the Viator website, and it even said the 9:30 time was preferred. I asked him what was available now and he said just to kayak in the water and go on the low tide beech if we wanted to. I then asked him about the clams and he said "what clam?" with the inflection that he did not even know what a clam was. The description of the tour on Viator said there would be sampling of different species of clams and mollusks and he did not even know what a clam was and when asked about a mollusk since that is the Portuguese term he confirmed that was not happening and seemed to not remember it ever happening. We still went on the kayak trip since we came all the way there. We went on the shore where we saw the locals digging up the very small clams and putting them in their own individual buckets. Since I was there for the clams, I grabbed a random empty shell (the locals were using small hand hoes) and started digging up some of the clams. They were all very small and undersized but I still took home about 8 of them after 30 minutes of digging and cooked them up. They were all of the same species. Tasty they were but hardly a meal. I was expecting different mollusks and seeing different ways to catch them. This was hardly that, and if you want the same experience don't go all the way to Ria Formosa you can just do that in Lisbon if that is where you are at. If I were to rate the overall kayak experience I would give it 3 stars, the ria formosa is just a couple sandy beeches and occasionally a bird or two, nothing like some wild preserve or something. There were smelly motor boats skimming by, and it was tough paddling against the wind blowing us away from the docks. My wife was still happy just because of the humor of the whole thing and my passion about mollusks, but I was expecting more.