One of the pleasures of being home after an adventure is sorting photos of the trip. But as I go through pictures of my recent sailing trip in Australia’s Great Barrier Reef Marine Park, I’m also enjoying the images my mind took when it was too dark or too distant to shoot, or when I didn’t feel like looking at something marvelous through a lens.

One late afternoon, after sailing all day, the weather took a turn, and we raced for shelter in a mainland waterway called Island Head Creek. As our boat turned the corner of the large island protecting the creek’s entrance, the world, like magic, changed from screaming wind and bucking boat into flat, calm silence.

Craig dropped the anchor, and we stood on the deck watching herons, cormorants and other water birds hunt for fish.

“Look!” Craig said, “A crocodile!”

The estuaries along the northern Queensland coast are famous for salties. But no. When the brown back Craig had seen reappeared, the creature also raised its head to take a breath. It was a dugong.

Dugongs are the Southern Hemisphere’s version of the manatee, both called sea cows and both endangered species. Like manatees, dugongs are slow, harmless vegetarians that graze on sea grasses in tropical creeks, rivers and estuaries.

When another of these rare marine mammals appeared on the other side of the boat, we watched the two pop up for air and dive down for food for a glorious half-hour. In the meantime the setting sun turned the water pink, then orange, then dark red. Island Head Creek — a dugong sanctuary, we later learned — became one of our favorite anchorages.

Another series of events I downloaded in brain only were endless flocks of shearwaters and black noddies. Soon after I wrote that I missed seeing flocks of seabirds at sea, we sailed to what’s known as the Bunker Group, the line of atolls that form the southern end of the Great Barrier Reef. The Bunkers’ coral reefs encircle sandy, wooded islands where black noddies build nests in trees and wedge-tailed shearwaters dig burrows for their eggs and chicks.

Near these outer reefs and islands, the water swarmed with seabirds, the shearwaters riding the air currents above the waves, and both species gathering in thousand-bird feeding frenzies, called bird piles in Hawaii, over schools of small fish.

Usually when one of us spots a bird pile, we point it out to the other. Not in the Bunkers. The birds were so abundant that we just sat in the cockpit, marveling in silence as Honu sailed through the feathered masses.

Near the end of the trip, three bottlenose dolphins came rushing to Honu to ride its bow wave. I made my way to the bow, purposely leaving the camera in the cockpit. I wanted to look at the dolphins the way they look at me. And it happened. As I looked down, a dolphin turned on its side to look up. Eye to eye, we shared a moment.

In this age when the phone I carry in my pocket is a camera as well, I often feel compelled to take pictures of everything that happens. No need. Without photos my experiences are as bright and animated in my memory as if I were watching a video. Fortunately, my senses record in high def.

Reach Susan Scott at susanscott.net.