Our party of five took Sea and Land's day tour to Coronado Island and had a blast on the boat, on the island, and snorkeling. I would highly recommend their tour, largely on the skill of our captain and his commitment to showing us all of what the island has to offer. We didn't try their other tours, but based on our Coronado day, I wish we had used them for some of our other day trips.
What We Did. We left the Loreto Harbor on an open panga (boat) and circled the island, pausing to view former lava flows, a sea lion colony, an osprey nest, and numerous blue-footed *oobys (substitute "b" for the * for the common name of the bird which isn't allowed in reviews). We then put ashore on a calm, shallow sandy beach on the east side of the island for lunch (tacos/quesadillas + water/soda/beer). The captain gave us a short walking tour pointing out a number of the unique plants and animals of the island and the efforts being taken to preserve them. We then had plenty of time for snorkeling around the coral beds in the remarkably clear water of the cove with provided snorkel gear. There are several areas to snorkel, but we didn't have to swim more than 50 yards off-shore to see several dozen types of fish (including a scorpion fish).
What to know if you go. Ask about the weather when you book the tour and have the staff pick a calm day if they can. We were visiting in November and chose the calmest day, but the wind did pick up after we started. If the seas are calm, they'll let you snorkel around the sea colony, which we missed. If you're photographing, it will also be easier to get clear, focused pictures from the boat. Also, be prepared to get wet in the boat unless the weather is calm. Our Captain let us snorkel a bit longer than he probably would've liked and we got drenched on our return as the increasing winds made the waters quite choppy. This, however, was almost as fun as the snorkeling and we had no fear because the Captain was a pro surfing on the waves into the harbor. Finally, snorkeling at the cove is great for even novices. We didn't encounter any rays and you can easily see most of the fishes and corals without venturing into water deeper than 4-5 feet.
One last suggestion: the name is Sea and Land, but if you're meeting them at their office rather than the harbor, their office sign is in Spanish. So look for a sign that you see Mar y Tierra, and you won't be disappointed.
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