Muggles' Guide to Harry Potter/Magic/Mooncalf

Overview
An extremely shy creature that emerges from its burrow only at the full moon, the Mooncalf has a smooth, pale grey body, bulbous eyes on the top of its head, four spindly legs, and large, flat feet.

Extended Description
When they emerge from their burrows, mooncalves engage in complicated geometric dances, which are believed to be in some way related to mating. The patterns these dances leave in fields have mystified Muggle farmers and fueled many interstellar conspiracy theories.

If collected before sunrise, the silvery dung of the Mooncalf provides an extremely good fertilizer for magical herb and flower gardens.

Analysis
The term "mooncalf" actually appears in Muggle literature, typically used to refer to a lovestruck youth, always mooning after the object of his affections. Muggle mooncalves are not known either for their dancing ability or the quality of their droppings, though they often seem to trip over their own feet, as if they were overlarge, and can appear almost painfully shy, particularly if the one they are following happens to look at them.

Greater Picture
While mooncalves never directly appear in the principal seven books, we suspect there might be a passing reference made to "mooncalf dung" by Professor Sprout at some point in the series.