One animal in which the effects of the moon are well-documented is the California grunion. The California grunion is a silvery fish about six inches long, and for most of its life it is unremarkable. During certain full and new moons every year, when the tide is at its highest, the grunion deliberately beach themselves on the shore. There, they mate and lay eggs in the wet sand before being washed out to sea again by the waves. About ten days later, the eggs (those that have not been eaten by predators, at least) hatch, and the young fish enter the sea again.
Similarly, the streamlined spinefoot, a member of the rabbitfish family (so-named because of their rabbit-like teeth and their appetite for plants) always lays its eggs when the moon is in its last quarter. It is unknown how the phases of the moon trigger the fish's reproductive drive, but when the moon is at the proper phase the male fish become flushed with hormones.
Lunar effects on land animals are much less well understood. One major exception is the fly Clunio marinus, which lives along the coasts of northern Europe. This insect has long been used as a model organism for the study of cyclic systems in living creatures. Its mating swarms, like the mating seasons of the grunion and the spinefoot, are timed with phases of the moon.
How do eclipses affect animals? That varies. We do know that during solar eclipses, birds will often stop singing, and nocturnal insects like crickets and will start chirping. But grunion, spinefeet, and Clunio flies have survived for millions of years despite the changes in the cycles of the moon, so clearly they have been able to weather whatever abnormalities of the lunar cycle can throw at them. Eclipses, for them, are simply a fact of life that they must deal with. And deal with it they do--it's what they're good at.
Deliberately washing themselves ashore to lay their eggs, California grunion are one of a number of animals whose activities are timed by the cycle of the moon--just as those of human eclipse-watchers are.
