Snowy egret

The snowy egret (Egretta thula) is a small white heron. The genus name comes from the Provençal French for the little egret aigrette, a diminutive of aigron, "heron". The species name thula is the Araucano for the black-necked swan, applied to this species in error by Chilean naturalist Juan Ignacio Molina in 1782.[3]

"Snowy heron" redirects here. For the 1958 Japanese film, see The Snowy Heron.

Snowy egret
Temporal range: Late Pleistocene-recent
0.126–0 Ma
↓

Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Pelecaniformes
Family: Ardeidae
Genus: Egretta
Species:
E. thula
Binomial name
Egretta thula
(Molina, 1782)
Range of E. thula      Breeding range     Year-round range     Wintering range
Synonyms
  • Ardea thula[2]
  • Leucophoyx thula[2]

The snowy egret is the American counterpart to the very similar Old World little egret, which has become established in the Bahamas. At one time, the plumes of the snowy egret were in great demand as decorations for women's hats.[4] They were hunted for these plumes and this reduced the population of the species to dangerously low levels.[5] Now protected in the United States by law, under the Migratory Bird Treaty Act, this bird's population has rebounded.

Description

Adult snowy egrets are entirely white apart from the yellow lores between the long black bill and the eye, black legs, and bright yellow feet. The nape and neck bear long, shaggy plumes known as aigrettes.[6] Immature snowy egrets have duller, greenish legs.

Distribution and habitat

The snowy egret is native to North, Central and South America. It is present all year round in South America, ranging as far south as Chile and Argentina. It also occurs throughout the year in the West Indies, Florida and coastal regions of North and Central America. Elsewhere, in the southern part of the United States, it is migratory, breeding in California, Nevada, Utah, Colorado, Arizona, New Mexico, Texas, Louisiana and Mississippi. It is found in wetlands of many types; marshes, riverbanks, lakesides, pools, salt marshes and estuaries. It is not found at high altitudes nor generally on the coast.[6] The snowy egret has occurred as a vagrant in Europe, in Iceland, Scotland and the Azores.[7]

Diet

The birds eat fish, crustaceans, insects, small reptiles, snails, frogs, worms and crayfish. They stalk prey in shallow water, often running or shuffling their feet, flushing prey into view by swaying their heads, flicking their wings or vibrating their bills. They may also hover, or "dip-fish" by flying with their feet just above the water surface. Snowy egrets may also stand still and wait to ambush prey, or hunt for insects stirred up by domestic animals in open fields. They sometimes forage in mixed species groups.[5]

Breeding

Snowy egrets breed in mixed colonies, which may include great egrets, night herons, tricolored herons, little blue herons, cattle egrets, glossy ibises and roseate spoonbills. The male establishes a territory and starts building the nest in a tree, vines or thick undergrowth. He then attracts a mate with an elaborate courtship display which includes dipping up and down, bill raising, aerial displays, diving, tumbling and calling. The immediate vicinity of the nest is defended from other birds and the female finishes the construction of the nest with materials brought by the male. It is constructed from twigs, rushes, sedges, grasses, Spanish moss and similar materials and may be 15 in (38 cm) across. Up to six pale bluish-green eggs are laid which hatch after about 24 days. The young are altricial and covered with white down when first hatched. They leave the nest after about 22 days.[5]

Fossil finds

Fossils of the snowy egret have been reported from the Talara tar seeps of Peru and in Bradenton in Manatee County and Haile XIB in Alachua County in Florida, United States.[2] The deposits were dated to the Late Pleistocene.[8][9][10][11]

Status

In the early twentieth century, the snowy egret was hunted extensively for their long breeding plumes that fashionable ladies wore on their hats. This trade was ended in 1910 in North America but continued for some time in Central and South America. Since then populations have recovered.[5] The bird has a very wide range and the total population is large. No particular threats have been recognised and the population trend seems to be upwards, so the International Union for Conservation of Nature has assessed its conservation status as being of "least concern".[1]

  • Head shot
  • Plumage displayed
  • Full breeding plumage
  • With chicks
  • Tayrona national park, Colombia
  • In flight
  • In flight
  • On the hunt, Daytona Beach, Florida, United States
  • Ponce Inlet Beach, Florida, United States.
  • A snowy egret and its hatchlings in St. Augustine, FL.
  • Snowy egret chicks in St. Augustine, FL
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References
  1. BirdLife International (2016). "Egretta thula". IUCN Red List of Threatened Species. IUCN. 2016: e.T22696974A93595536. doi:10.2305/IUCN.UK.2016-3.RLTS.T22696974A93595536.en. Retrieved 3 December 2019.
  2. Egretta thula at Fossilworks.org
  3. Jobling, 2010, p.143, 385
  4. Saikku, Mikko (Autumn 1990). "The Extinction of the Carolina Parakeet". Environmental History Review. 14 (3): 9–10. doi:10.2307/3984724. JSTOR 3984724.
  5. "Snowy Egret: Life History". All About Birds. TheCornellLab. Retrieved 29 March 2019.
  6. (T. S. Schulenberg, Editor). "Snowy egret (Egretta thula)". Cornell Lab of Ornithology: Neotropical Birds Online. Retrieved 28 November 2019.
  7. "Twitchers flock to see UK's first snowy egret". The Scotsman. Retrieved 25 December 2018.
  8. Talara tar seeps at Fossilworks.org
  9. Bradenton at Fossilworks.org
  10. Haile XIB at Fossilworks.org
  11. Ligon, 1966

Bibliography

Further reading
  • Stiles and Skutch, A guide to the birds of Costa Rica ISBN 0-8014-9600-4
  • National Geographic, Field Guide to the Birds of North America ISBN 0-7922-6877-6
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