BAR HARBOR – Think back to when you were small: Remember the grassy meadow or vacant lot where you spent boundless summer afternoons? Remember the thrill of discovering a cache of wild strawberries, a snakeskin or a nest filled with tiny specked eggs?

Though a towering man with white hair, naturalist and photographer Steve Perrin lives for these small discoveries. His Bar Harbor apartment is packed with seashells, stones, leaves and cones – remnants of weekly hiking expeditions in Acadia National Park.

“Grown-ups lose that sense of the natural world,” Perrin said. “They live in paved roads and sidewalks and buildings. [But] I have that sense still in me – I’m a noticer – and I never want to lose it.”

Perrin spent much of 2000 hiking Acadia’s trails and capturing his finds in photographs, which he arranged seasonally in a recently published book, “Acadia’s Native Flowers, Fruits and Wildlife.”

“I try to sensitize people to that other world that we share,” he said. “These are my neighbors – I love them dearly,” Perrin said of the plants and animals featured in his book.

The tiny volume, just 5 inches square, serves as both a field guide and an artist’s tribute, with 143 detailed color photographs of the plants and animals a hiker is likely to encounter in the park.

“I call it the world’s smallest coffee-table book,” he said.

Perrin has been hiking and photographing Hancock County for the better part of 30 years, and has published several books filled with musings and images inspired by the region’s natural beauty.

“I absolutely believe that the Maine coast is unique in the world,” he said. “I wouldn’t live anyplace else but Maine. This is my habitat.”

But during 2000, Perrin went out hiking alone nearly every day, seeking subjects for his book, and conversing with the natural elements of the park. The book is a historical record – a snapshot of the ever-evolving natural world at the beginning of the 21st century, he explained.

“It was a great adventure – I never knew what I was going to find,” he said. “Every time I go in the park, I see something I’ve never seen before.”

More than 1,800 species of plants are known to live in Acadia; some 76 fit into Perrin’s book. He limited the guide to native plants – tiny species such as wintergreen, bearberry and mountain sandwort – while common, but foreign species, including lupine and rosa rugosas, were excluded.

“I think they’re more beautiful than the showy dahlias and orchids you can put in your garden,” Perrin said of the native species. “They’re the plants that belong here – they’re native Mainers.”

Wildlife, too, had to meet Perrin’s strict standards – many of the species in the book are unappreciated – frogs, turtles and insects, he said.

“I tried to show the wildlife that you’re apt to see, not just the charismatic mammals with the great big eyes,” Perrin said. “You’re much more likely to see a frog on the trail than a deer or a moose.”

Most hikers pass the little species by or worse – trample them. The summit of Cadillac barely resembles other Acadian mountaintops, because much of its fauna is gone, he said.

But if Perrin notices an interesting species while hiking, he stops short and folds his lanky frame to peer through his camera, capturing a touch-me-not blossom or a glistening dragonfly.

“Hikers need to look down at their feet. I spent a lot of time down on my hands and knees in bogs, getting wet,” he said, laughing. “And I’m 6 feet 3 inches. I’m pretty far from that world.”

But Perrin shares his unique world in words and images in “Acadia’s Native Flowers, Fruits and Wildlife.” He calls the book a portrait of the personal way in which he experiences the natural world.

“We make our worlds,” he said. “If we look for ugliness and pain, we’ll find it. But if we look for beauty, we’ll find that, too.”

“Acadia’s Native Flowers, Fruits and Wildlife” is available for $12.95 at local bookshops in Acadia National Park, Ellsworth, Bar Harbor and Somesville. It may also be ordered direct from Perrin at earthling@acadia.net. A book signing will take place from 1 to 3 p.m. Saturday, Nov. 24, at Sherman’s Bookstore in Bar Harbor.