Urohidrosis (sometimes misspelled "urohydrosis"[1]) is the habit in some birds of
defecating onto the scaly portions of the legs as a cooling mechanism, using
evaporative cooling of the fluids. Birds' droppings consist of both feces and urine, which are excreted together through the
cloaca.
...Because of its apparent functional similarity to true sweating, I suggest the term urohidrosis (Greek: ouron = urine; hidrōs = sweat) for this phenomenon.
Examples
Several species of
storks and
New World vultures exhibit this behaviour.[4][5] This behaviour leads to accumulation of droppings around leg
rings on ringed birds, which can lead to injury.[6]
The term is also used to describe the analogous behaviour in
seals that cool themselves while basking by urinating on their hind flippers.[7]
References
^Elliott, A. (1992). "Family Ciconiidae (Storks)". In del Hoyo, J; A. Elliott, J. Sargatal (eds.). Handbook of the Birds of the World. Vol. 1. Lynx Edicions, Barcelona. pp. 441–449.