Saturday, November 5, 2011

Great Blue Heron Habitats: Blue Body, Blue-Green Egg, Platform Nest


Summary: North American great blue heron habitats in coniferous and deciduous wooded wetlands sustain blue bodies, blue-green eggs and platform nests.


Great blue herons (Ardea herodias) build a lofty nest in Florida: Lee Karney/U.S. Fish and Wildlife Service, Public Domain, via USFWS National Digital Library

North American great blue heron habitats alleviate cultivator anxieties over meadow lizard and mouse populations and award naturalists with distribution ranges seasonally in Canada and Mexico and year-round in the United States.
The great blue heron bears its common name and the scientific name Ardea herodias ([Latin] heron [Greek] heron) as one of the world's three largest herons. Agro-industry, aquaculture, development, pesticides, pollution, predation, recreation and tourism challenge great blue herons, described in 1758 by Swedish zoologist Carl Linnaeus (May 23, 1707-Jan. 10, 1787). Freshwater and saltwater wetlands with ledges, mangroves and outcrops draw great blue herons into solitary and flocked life cycles with cormorants, ibises, other herons and pelicans.
Twenty-year lifespans in Canada summers, Mexico winters and the United States year-round expect inaccessible, remote flooded fields, lakes, mangroves, marshes, rivers, swamps and tidal grass flats.

November through August furnish opportunities in nesting and roosting colonies for brooding one two- to seven-egg clutch, preferably at 130 feet (39.62 meters) above the ground.
Fathers-to-be over three to 14 days give mothers-to-be branches and sticks for grass-, leaf-, twig-lined platform nests with 25- to 40-inch (63.5- to 101.6-centimeter) outside diameters. Nests house 1.85- to 2.79-inch (4.7- to 7.1-centimeter) by 1.38- to 1.97-inch (35- to 50-centimeter), oval, elliptical to subelliptical, pale blue-green, smooth or semi-rough, unmarked eggs. Parents-to-be incubate completed clutches for 25 to 30 days unless equipment operation and foot traffic inspire nest abandonment and institute repeat mating and second clutches elsewhere.
Agro-industry, aquaculturists and construction and bears, common and northwest crows, eagles, pollution, raccoons, ravens, red-tailed hawks and turkey vultures jeopardize North American great blue heron habitats.

Semi-helpless nestlings know blunt, short bills, bristle-tipped, long, smoky-gray down on crowns, long down on dark gray-brown upperparts and on pale gray flanks and white undersides.
The first three to four weeks parents lavish round-the-clock care on nestlings who learn to fly at 60 days and leave four to 30 days later. Nestlings mature on regurgitated fish from their parents' flexible, storageable digestive systems and mix physical independence within three, and sexual maturity within 22, months of hatching. Adults need nourishment from bass, crabs, crayfish, dragonflies, flounder, frogs, gophers, grasshoppers, gunnel, lizards, mice, perch, rails, salamanders, sculpin, shrimp, smelt, snakes, stickleback, turtles and voles.
North American great blue heron habitats up through 8,530.18-foot (2,600-meter) altitudes above sea level offer winter-coldest temperatures at minus 45 degrees Fahrenheit (minus 42.78 degrees Celsius).

Great blue herons prefer 2- to 4-mile (3.22- to 6.44-kilometer) distances between forages and nests and roosts in all-coniferous, all-deciduous or mixed forests, groves and woodlands.
Ash, aspen, birch, elm, fir, hemlock, hickory, mangrove, maple, oak, pine, spruce and white cedar qualify as camouflage alongside, in or near water bodies and wetlands. Blue-gray bodies, dark bills, legs and wing-tips, gray S-shaped necks crooked backward in flight and white faces reveal adult males with brown-bodied, dark-tailed females and juveniles. Deep-flapping, regular-beating flight on 5.25- to 6.5-foot (1.6- to 1.98-meter) wingspans suggest 2.75- to 4.25-foot (0.84- to 1.29-meter) long, 4.75- to 5.5-pound (2.15- to 2.49-kilogram) adults.
North American great blue heron habitats tend to transmit no voices other than the barking, loud squawk and crank vocalizations of breeding colonies and disrupted flocks.

illustration of great blue heron (Ardea herodias) eggs; Illustrations of the Nests and Eggs of Birds of Ohio, Plate LIV, figure 7, opp. page 188: Public Domain, via Biodiversity Heritage Library

Acknowledgment
My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:
Great blue herons (Ardea herodias) build a nest in Florida: Lee Karney/U.S. Fish and Wildlife Service, Public Domain, via USFWS National Digital Library @ https://digitalmedia.fws.gov/cdm/singleitem/collection/natdiglib/id/17740/rec/3
illustration of great blue heron (Ardea herodias) eggs; Illustrations of the Nests and Eggs of Birds of Ohio, Plate LIV, figure 7, opp. page 188: Public Domain, via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/34908331

For further information:
Audubon, John James. "Great White Heron Ardea occidentalis." Ornithological Biography or, An Account of the Habits of the Birds of the United States of America; Accompanied by Descriptions of the Objects Represented in the Work Entitled The Birds of America, and Interspersed with Delineations of American Scenery and Manners, vol. III: 542-552. Edinburgh Scotland: Adam and Charles Black, MDCCCXXXV (1835). Vol. III, p. 542-552 and Vol. V, p. 596.
Available via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/33238012
Audubon, John James. 1839. "Great White Heron Ardea occidentalis." Ornithological Biography or, An Account of the Habits of the Birds of the United States of America; Accompanied by Descriptions of the Objects Represented in the Work Entitled The Birds of America, and Interspersed with Delineations of American Scenery and Manners, vol. V: 596-599. Edinburgh Scotland: Adam and Charles Black, MDCCCXXXIX.
Available via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/33240594
Baicich, Paul J.; and Harrison, Colin J.O. Nests, Eggs, and Nestlings of North American Birds. Second edition. Princeton NJ: Princeton University Press, Princeton Field Guides, 2005.
Bangs, Outram. "Description of a New Race of the Great Blue Heron From the Galapagos islands: Ardea herodias cognata subsp. nov." Proceedings of the New England Zoölogical Club, vol. III (Feb. 6, 1903), pp. 99-100.
Available via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/12603773
Chapman, Frank M. "A New Race of the Great Blue Heron, With Remarks on the Status and Range of Ardea wardi: Ardea herodias fannini, subsp. nov." Bulletin of the American Museum of Natural History, Vol. XIV, Article VIII (April 18, 1901), pp. 87-90.
Available via AMNH Research Library Digital Repository @ http://digitallibrary.amnh.org/bitstream/handle/2246/734//v2/dspace/ingest/pdfSource/bul/B014a08.pdf?sequence=1&isAllowed=y
Grzimek's Animal Life Encyclopedia, 2nd edition. Volumes 8-11, Birds I-IV, edited by Michael Hutchins, Jerome A. Jackson, Walter J. Bock and Donna Olendorf. Farmington Hills MI: Gale Group, 2002.
Jones, Howard. 1886. Illustrations of the Nests and Eggs of Birds of Ohio. Illustrations by Mrs. N.E. Jones. Vol. II. Circleville OH: s.n. (sine nomine).
Available via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/34908243
Linneaus, Carl. 1758. "11. Ardea herodias." Systema Naturæ: 143. Editio Decima, Reformata. Holmiae [Stockholm, Sweden]: Laurentii Salvii [Laurentius Salvius].
Available via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/727050
Peterson, Alan P., M.D. "Ardea herodias Linnaeus 1758." Zoonomen: Zoological Nomenclature Resource > Birds of the World -- Current Valid Scientific Avian Names > Pelecaniformes > Ardeidae > Ardea.
Available @ http://www.zoonomen.net/avtax/pele.html
Ridgway, Robert. "On an Apparently New Heron from Florida." Bulletin of the Nuttall Ornithological Club, vol. VII, no. 1 (January 1882), pp. 1-6.
Available via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/21225900



No comments:

Post a Comment

Note: Only a member of this blog may post a comment.