Within One Watershed:

Essays from Hackleman Creek

Part 3

The Lake

Summer

For three millennia the waters of Hackleman Creek have followed a slow rhythm of pooling and draining in Fish Lake: filling the lakebed in April and emptying it to reveal a verdant meadow in early July. But now the pattern has changed; the undeniable evidence lies before our trio of hikers. The second week of June has just ended, August-like temperatures bear down on us and the lake is completely gone. Unusually warm spring temperatures depleted a snowpack already diminished by less-than-normal winter snowfall; the meltwater briefly filled the lake, but the porous lava sucked it dry sooner than ever before.

Grass-like sedges have sprouted in thick bunches on the lakebed. As their underground stems, called rhizomes, spread and produce new shoots, the clumps will thicken and join to carpet the ground in green, creating cover and forage for terrestrial insects, mammals and birds.

For some organisms, however, the meadow’s premature birth brings early death. As we follow a dry channel that curves across the lakebed between sedge-lined banks, in lieu of the usual shallow flow or lingering puddles we see dried mud cracking in the sun and countless dead case-maker caddisfly larvae. After hatching in water, these macroinvertebrates become miniscule stonemasons, each constructing a rigid case around itself made of tiny rocks bonded by silk excreted from glands near its mouth. On the dried-up lakebed, these cases no longer protect the soft larvae as they were intended; instead, they’ve become pebbly caskets holding desiccated corpses. The creatures’ aquatic habitat vanished way too early, depriving them of a chance to grow, pupate underwater and emerge as free-flying adults.

We follow the dry watercourse west, hoping to find moisture. After 200 yards we see the stagnant remains of a stream. Hundreds of caddisfly and mayfly larvae crowd the small pools, packed together like New Year’s revelers in Times Square. But these little creatures aren’t celebrating; caddisfly larvae pile atop one another in the confined space while the mayfly nymphs dart back and forth, bumping into each other as they frantically search for deeper, cooler water. Cramming into these shrinking pools bought these creatures a little time but, ultimately, they face the same fate as the dead ones we saw earlier.

Moving farther upstream, we eventually find a flowing creek bisecting the wide meadow. Crayfish patrol the bottom and a garter snake slithers through sedges, emerging in the shallows, a bright yellow dorsal stripe running down the length of its black body. Here, young caddisfly and mayfly larvae appear to be thriving in uncrowded conditions.

Working our way slowly along the water’s edge, we spot a large salamander, about eight inches long, lolling in the stream. Its marbled brown skin, thick legs and wide head indicate it’s a pacific giant salamander. Creeping closer, we see its vertically flattened tail and notice short fuzzy gills extending from each side of its head.

Unusual creatures, pacific giant salamanders can grow to be a foot long, and have been known to bark when disturbed. A juvenile will spend two to three years in its  aquatic form, then metamorphose into a terrestrial adult with internal lungs replacing its external gills. Each secretive adult spends most of its time hidden under logs or rocks within 200 yards of its natal stream.

In a strange evolutionary twist, some pacific giant salamanders remain in their juvenile aquatic form their entire lives. This baby-like appearance is misleading, though, as they are able to mate and reproduce.

Resisting the urge to catch this creature, I kneel in the hot sun and ponder its fate. If it’s the type that develops into a terrestrial adult, will the water linger long enough for it to complete its metamorphosis? If it keeps its gilled aquatic form into adulthood, will it be able to move upstream when this part of the creek runs dry? The odds seem stacked against it.

As we slowly head back, I realize that in our search for water, we’ve been looking down all afternoon. Lifting my gaze, I take in the larger scene: the peaked roof of a century-old Forest Service cabin rises above a hill overlooking the meadow. A winged shadow skims across the green as a warm updraft carries a soaring Turkey Vulture in slow circles. Old cottonwoods stand sentinel in the east as the breeze flips each individual leaf, alternately revealing dark green on the upper side and shimmering silver below. Hidden in this idyllic scene is the sad truth that, for some aquatic creatures, summer has come too soon. Their demise is a somber prelude to what may lie ahead for this small watershed and the planet as a whole.