The green heron (Butorides virescens) is a small heron of North and Central America. Butorides is from Middle English butor "bittern" and Ancient Greek -oides, "resembling", and virescens is Latin for "greenish". The green heron is relatively small; adult body length is about 44 cm (17 in). The neck is often pulled in tight against the body. Adults have a glossy, greenish-black cap, a greenish back and wings that are grey-black grading into green or blue, a chestnut neck with a white line down the front, grey underparts and short yellow legs. The bill is dark with a long, sharp point. Female adults tend to be smaller than males, and have duller and lighter plumage, particularly in the breeding season. Juveniles are duller, with the head sides, neck and underparts streaked brown and white, tan-splotched back and wing coverts, and greenish-yellow legs and bill. Hatchlings are covered in down feathers, light grey above, and white on the belly.
The Green Heron occurs from temperate North America south to Colombia and Venezuela including the West Indies (Raffaele and others 1998), where it is a common resident species in Puerto Rico (Oberle 2018) and fairly common on Vieques (Gemmill 2015). The Green Heron inhabits freshwater and saltwater marshes, as well as ponds, canals, mangroves, stream borders, ocean shores, and even gardens (Oberle 2018). The atlas fieldwork yielded a total of 492 records within 284 hexagons or 59 percent of the 479 total hexagons (see map). Of the 284 hexagons where this species was found, breeding met the atlas definition of confirmed in 12 percent (33) of the hexagons, probable in 11 percent (31), and possible in 76 percent (215), while the species was observed in 2 percent (5) of the hexagons but without evidence of breeding (see map). Green Heron 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 Green Heron often nests alone but also in treetop colonies (Oberle 2018). This species constructs a platform nest of twigs in a tree or shrub (Raffaele and others 1998), usually near reservoirs, ponds, lagoons, 157Green Heron/Martineterivers, creeks, and streams from the coast to the highest peaks (J.A. Salguero-Faría, personal observation 2009). Previously published reports indicate that it breeds mostly from April to August (Raffaele and others 1998). Atlas results indicate that this species breeds throughout the year, but most breeding activity occurs during April, May, and June (see chart). Atlas findings show that the Green Heron breeds within all ecological life zones, but the most breeding occurs within the subtropical moist forest life zone (61 percent of the hexagons), followed by the subtropical dry (25 percent of the hexagons) and subtropical wet forest life zones (14 percent of the hexagons) (see table and map).
The Green Heron has not yet been assessed by the IUCN Red List. Locally, this species is not listed in any of the threatened categories of PRDNER and USFWS. In Puerto Rico, the Green Heron has a protected habitat in land of 9 percent or 633 km2 of the total area covered by the hexagons where evidence of breeding was found for this species (6671 km2).