Grunion until the next tide series high enough reaches them 10 or more days later. Grunion eggs can extend incubation and delay hatching if tides do not reach them for an additional four weeks after this initial hatching time. Most of the eggs will hatch in 10 days if provided with seawater and the agitation of the rising surf. The mechanical action of the waves is the environmental trigger for hatching. The rapidity of hatching, which occurs in less than one minute, indicates it is probably not an enzymatic function of a softening of the chorion as in some other fishes.
USS Grunion bow. The wreckage then slid two-thirds of a mile down the side of an extinct volcano, coming to rest on a notch in the underwater mountain. USS Grunion USS "Grunion" (SS-216) was a "Gato"-class submarine that was sunk at Kiska, Alaska, during World War II. She was the only ship of the United States Navy to be named for the grunion. Her keel was laid down by the Electric Boat Company in Groton, Connecticut on 1 March 1941. She was launched on 22 December 1941, (sponsored by Mrs. Stanford C. Hooper, wife of Rear Admiral Hooper), and commissioned on 11