The glossy ibis (Plegadis falcinellus) is a water bird in the order Pelecaniformes and the ibis and spoonbill family Threskiornithidae. The scientific name derives from Ancient Greek plegados and Latin, falcis, both meaning "sickle" and referring to the distinctive shape of the bill. This species is a mid-sized ibis. It is 48–66 cm (19–26 in) long, averaging around 59.4 cm (23.4 in) with an 80–105 cm (31–41 in) wingspan. The culmen measures 9.7 to 14.4 cm (3.8 to 5.7 in) in length, each wing measures 24.8–30.6 cm (9.8–12.0 in), the tail is 9–11.2 cm (3.5–4.4 in) and the tarsus measures 6.8–11.3 cm (2.7–4.4 in). The body mass of this ibis can range from 485 to 970 g (1.069 to 2.138 lb). Breeding adults have reddish-brown bodies and shiny bottle-green wings. Non-breeders and juveniles have duller bodies. 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. Unlike herons, ibises fly with necks outstretched, their flight being graceful and often in V formation. It also has shiny feathers.
The Glossy Ibis occurs worldwide including the West Indies, where it is irregular and very local in Puerto Rico (Raffaele and others 1998). Before the early 2000s, this species was considered a rare visitor until it was confirmed to be nesting in the municipality of Arecibo (J.A. Salguero-Faría, personal observation 2009). It has expanded throughout coastal wetlands and now can be seen in fl ocks that number hundreds of birds (J.A. Salguero-Faría, personal observation 2009). This species occurs in lowland habitats (Oberle 2018) including mud fl ats and marshy savannas (Raffaele and others 1998). The atlas fieldwork yielded a total of 27 records within 13 hexagons or 3 percent of the 479 total hexagons (see map). Of the 13 hexagons where this species was found, breeding met the atlas definition of confirmed in 15 percent (2) of the hexagons, while the species was observed in 85 percent (11) of the hexagons but without evidence of breeding (see map). Glossy Ibis distribution. The map shows the highest breeding code by hexagon and overlaying the ecological life zones in Puerto Rico. Note: percentages may not total 100 due to rounding.
The Glossy Ibis nests in colonies and constructs the nest near water, principally from June to August, according to previously published reports (Raffaele and 165Glossy Ibis/Ibis Lustrosoothers 1998). The two instances of reported Glossy Ibis breeding in Puerto Rico occurred in the month of June (see chart). Results show that the Glossy Ibis breeds within the subtropical moist forest life zone (100 percent of the hexagons) (see table and map).
The population trend for the Glossy Ibis across its distribution range is described as decreasing, mainly due to wetland habitat degradation and loss, but it is listed as a species of least concern by the IUCN (BirdLife International 2019). Locally, this species is listed as Data Deficient (PRDNER 2015). In Puerto Rico, the Glossy Ibis has a protected habitat in land of 15 percent or 7 km2 of the total area covered by the hexagons where evidence of breeding was found for this species (~48 km2).