Gular skin

Gular skin is a term used in ornithology for an area of featherless skin on birds, that joins the lower mandible of the bill, to the bird's neck.Cite web|url=http://www.virtualmuseum.ca/Exhibitions/Birds/MMMN/English/glossary_data.html|title=Glossary of Ornithology Terms|accessyear=2008|accessmonthday=July 29|publisher=Manitoba Museum of Man and Nature|year=2008|author=Manitoba Museum of Man and Nature]

It is prominent, for example, in members of the order Pelecaniformes. In many species, the gular skin forms a flap, or gular pouch, which is generally used to store fish and other prey while hunting.

In Cormorants, the gular skin is often coloured, contrasting with the otherwise plain black or black-and-white appearance of the bird. This presumably serves some function in social signalling, since the colours become more pronounced in breeding adults.

In Frigatebirds, the gular skin or sac is used dramatically. During courtship display, the male forces air into the sac, causing it to inflate over a period of 20 minutes into a startling huge red balloon.

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