If you're a parent of a budding naturalist, waste no time in taking the family to Little Three Creek Lake for a memorable experience of amphibian metamorphosis.

Baby toadlets are hatching in biblical proportions right now, swarming the shoreline, offering enchanting entertainment for youngsters who might otherwise wonder what the purpose of hiking is.

This metamorphosis — the transition from tadpole to toad — of Western toads should last through the weekend, although tiny toads will probably be prolific around the lakeside meadows until the first rain, according to local amphibian expert Jay Bowerman.

On Monday, my husband, Brent Fenty, and I took our 6-year-old daughter Adi on a kid-friendly hike (in other words, extremely short, on a developed trail) to Little Three Creek Lake, near the bigger and more heavily populated Three Creek Lake, a half-hour outside of Sisters.

The shallow, cold, green lake nestled under the dramatic wall of Tam McArthur Rim is in itself a scenic and worthy destination for a picnic or a swim.

But it was the toad scene Monday that made it memorable.

There appear to be a few trails to access Little Three Creek Lake, so you can make it a 3-mile out-and-back or an even shorter loop hike like we did. As you approach the north shore of Three Creek Lake (see “If you go," Page B6), look for the Driftwood Campground and adjacent trailhead parking lot on the right. This accesses an unmarked, dusty trail that will lead to Little Three Creek Lake.

We wanted to check out the campground, so we drove another half mile or so through it, and found a sign that announced “Little Three Cr. Lk." at the end of the campground, so we parked there instead and started walking on the trail uphill through a pretty, shaded forest.

Within 15 minutes or so we reached a very small, unnamed shallow lake, just southeast of Little Three Creek Lake.

My daughter waded into the frigid snowmelt of this pothole and proceeded to swim across an arm of it, getting herself so cold that we had to wrap her up in a towel, change her into dry clothes and eat lunch right then, at about 10:30 a.m.

She felt satisfied by the adventure and was ready to go home, but we made her walk farther because we were pretty sure that wasn't the lake we were aiming for, and besides, at this point, we'd spent more time driving than enjoying the outdoors.

Just a couple of hundred feet to the northwest, we saw Little Three Creek Lake, which was larger but otherwise similar in scenery. Both lakes had a tent or two perched on some idyllic camp spots, and both offered a handful of access points for wading or swimming.

Little Three Creek Lake is where we discovered the toads, which reinforced Brent's message to Adi: You should always keep hiking; you never know what you might find around the next corner.

Along the grassy shore, we noticed a slimy, writhing black mass clustered in the shallow waters against the banks. Drier piles of what Adi had at first thought was manure or scat of some sort turned out to be piles of the half-inch-long toads, drying out, discovering what it meant to have legs. Most of them were blackish, but the occasional amphibian glittered with a shimmery gold color, or shone with the brightest of greens.

As we tuned in to the creatures, we realized the tadpoles and toads were everywhere. They bounded away from every step we took across the mossy, mushy meadows. We had to tiptoe at a snail's pace to avoid stepping on them.

We called them frogs at the time, but I later checked with Bowerman, the principal researcher at the Sunriver Nature Center and author of more than a dozen scientific articles on amphibian biology, who informed me that they were actually Western toads (Bufo boreas).

I asked Bowerman in an email: “What is going on here!?"

He replied that this species lays eggs over the course of a few hours on a sunny day in June or July at this elevation (we were around 6,700 feet).

Bowerman continued to explain what we had seen: “The tadpoles gather in amazingly large numbers and swim around in vast schools. As they approach metamorphosis, their front legs are fully formed but still hidden under the skin at the area of the shoulders.

“At this time, they begin to congregate along the shoreline, often in a fairly narrow stretch of shore. Over the course of a few days, the front legs burst forth and the tails start to resorb, and the little toadlets climb up on the shore. Each day more arrive on the shore and pile up as you saw.

“If the weather stays warm and dry, many of them remain near the shore, waiting for rain, at which time they make a dash for the forest. If rain doesn't come, some of the toadlets begin to get anxious and they start to diffuse outwards from the 'beach landing' site, and over time, more and more head out. They won't actually return to the lake for another four to five years, at which time they reach breeding age and return to the lake to spawn. Some of them may have more than a mile or two of travel to get back to their natal lake."

The timing of this annual metamorphosis varies at high-elevation sites, depending on when the snow leaves the lake and surrounding uplands. “This year is somewhat later than average due to the heavy high-elevation snowpack and a prolonged cool spring," Bowerman wrote.

Adi was enraptured by the experience. She loves small things, and has her father's knack for the sciences. While Brent and I sat on the soft, damp ground and had an actual conversation, she spent at least an hour catching and releasing the creatures, humming happily and naming them (Greeny, Goldie, Hoppy, Droppy, Spots, Dots, Shimmery and Toothless).

She built a toad habitat with moss, sticks, dirt and leaves in a plastic container left over after lunch, and tried to fill it with toads. The little hoppers were skilled in the art of escape, though, so it was an endless task.

Even though Adi had been ready to go home after her quick swim in the first lake we came upon, now we had to convince her that it was time to go. She dragged her feet. She slowly said goodbye to her new pets, unloading the habitat one toad at a time.

We hiked out in the opposite direction from where we had come in, to make a loop of our walk. From the north end of the lake, we found the trail that is about 1.5 miles, one-way, back to the trailhead parking lot.

The trail was lovely near the lake, meandering along a gurgling mountain stream, peppered with blue gentian and pink monkey flowers. It passed through lodgepole pines, fir and hemlock trees. But its lower reaches led through a forest of dead and fallen trees, in a very dusty area. From the trailhead parking area, the walk through the Driftwood Campground back to our truck was short.

If you're taking a really young hiker, I'd suggest just walking in and out from the end of the campground. It seemed like no more than a half-mile, each way. I liked doing the loop in the name of exploration, which made for an under-three-mile hike.

This set of lakes would make an ideal destination for some beginner backpacking trips for youngsters, which is exactly what I intend to do next summer with Adi, in hopes that we'll get to witness this metamorphosis of toads again.