This was a section of the canyon that Anna hated to hike, though its austere beauty lured her back time and again. The high walls, with their steep sloping shoulders sliding down to slick-sided pits, put a clutch in her stomach. Further down the white basins would be filled with crystal waters, darting yellow sunfish: life. But here the river had deserted the canyon for a world underground and left only these oddly sculpted death traps. Anna entertained no false hopes that her radio signal would reach up over the cliffs and mountains to summon help if she were to lose her footing.

She crawled the distance on hands and knees.

Even heralded by perfume and music, the water took her by surprise. Sudden in the bleak bone-white canyon came an emerald pool filled by a fall of purest water. The plop of fleeing frogs welcomed her and she stopped a moment just to marvel.

Aware of the ache across her shoulders, Anna loosed the straps and let her pack fall heavily to the limestone. At the abrupt sound there was an answering rattle; a rushing sound that brought her heart to her throat. With a crackling of black-feathered wings and a chatter of startled cries, a cloud of vultures fought up out of the saw grass that grew along the bench on the south side of the pool.

They didn't fly far, but settled in soot-colored heaps along the ledges, looking jealously back at their abandoned feast.

Anna looked to where they fixed their sulky eyes.

Saw grass, three-sided and sharp, grew nearly shoulder-high along the ledge beyond the pool. From a distance the dark green blades, edged with a paler shade, looked soft, lush, but Anna knew from experience anything edible in this stark land had ways of protecting itself. Each blade of saw grass was edged with fine teeth, like the serrated edge of a metal-cutting saw.