only known way to kill and preserve them; atomics are the only explosive powerful enough to kill an entire worm, with conventional explosives being unfeasible as "each ring segment has a life of its own". Water is poisonous to the worms, but it is in too short supply on Arrakis to be of use against any but the smallest of them. Life cycle Herbert notes in Dune that microscopic creatures called sand plankton feed upon traces of melange scattered by sandworms on the Arrakeen sands. The sand plankton are food for the giant sandworms, but also grow and burrow to become what the Fremen call Little Makers, "the half-plant-half-animal deep-sand vector of the Arrakis sandworm". Their leathery remains previously having "been ascribed to a fictional sandtrout in Fremen folk stories", Imperial Planetologist Pardot Kynes had discovered the Little Makers during his ecological investigations of the planet, deducing their existence before he actually found one. Kynes determines that these "sandtrout" block off water "into fertile pockets within the porous lower strata below the 280° (absolute) line", and Alia Atreides notes in Children of Dune that the "sandtrout, when linked edge to edge against the planet's bedrock, formed living cisterns". The Fremen themselves protect their water supplies with "predator fish" that attack invading sandtrout. Sandtrout can be lured by small traces of water, and Fremen children catch and play with them; smoothing one over the hand forms a "living glove" until the creature is repelled by something in the "blood's water" and falls off. Leto II says in Children of Dune: The sandtrout are described as "flat and leathery" in Children of Dune, with Leto II noting that they are "roughly diamond-shaped" with "no head, no extremities, no eyes" and "coarse interlacings of extruded cilia". They can find water unerringly, and squeezing the sandtrout yields a "sweet green syrup". When water is flooded into the sandtrout's excretions, a pre-spice mass is formed; at this "stage of fungusoid wild growth", gases are produced which result in "a characteristic 'blow', exchanging the material from deep underground for the matter on the surface above it". After exposure to sun and air, this mass becomes melange. Kynes' "water stealers" die "by the millions in each spice blow" and may be killed by even a "five-degree change in temperature". He notes that "the few survivors entered a semidormant cyst-hibernation to emerge in six years as small (about