Male frigatebirds attract mates with an elastic, red gular pouch that is inflatable.

References

"A male frigatebird or Man-o-war bird has selected a suitable nest site and is advertising for a mate by inflating its crimson throat pouch. As soon as the first egg is laid, the pouch will be deflated." (Foy and Oxford Scientific Films 1982:76)

Book
The grand design: Form and colour in animalsJanuary 1, 1970
Sally Foy

Living System/s

Organism
Magnificent Frigate BirdFregata aquilaSpecies