The scientific name derives from Ancient Greek plegados and Latin, falcis, both meaning "sickle" and referring to the distinctive shape of the bill.

[1] It disappeared as a regular breeding bird in Spain in the early 20th century, but re-established itself in 1993 and has since rapidly increased with thousands of pairs in several colonies.

[9] An increasing number of non-breeding visitors are seen in northwestern Europe, a region where glossy ibis records historically were very rare.

In New Zealand, a few birds arrive there annually, mostly in the month of July; recently a pair bred amongst a colony of royal spoonbill.

[16][17] Year-long studies have also shown Glossy ibises to be foraging in agricultural wetlands and flooded farmlands in western India.

Glossy ibises often roost communally at night in large flocks, with other species, occasionally in trees which can be some distance from wetland feeding areas.

Glossy ibises feed in very shallow water and nest in freshwater or brackish wetlands with tall dense stands of emergent vegetation such as reeds, papyrus (or rushes) and low trees or bushes.

They show a preference for marshes at the margins of lakes and rivers but can also be found at lagoons, flood-plains, wet meadows, swamps, reservoirs, sewage ponds, paddies and irrigated farmland.

Prey includes adult and larval insects such as aquatic beetles, dragonflies, damselflies, grasshoppers, crickets, flies and caddisflies, Annelida including leeches, molluscs (e.g. snails and mussels), crustaceans (e.g. crabs and crayfish) and occasionally fish, amphibians, lizards, small snakes and nestling birds.

This species has a brownish bill, dark facial skin bordered above and below in blue-gray (non-breeding) to cobalt blue (breeding), and red-brown legs.

Glossy ibises can be threatened by wetland habitat degradation and loss through drainage, increased salinity, groundwater extraction and invasion by exotic plants.