Hawksbill Sea Turtles: Green-Brown Upper-Shell, Yellow Lower-Shell

Summary: North American hawksbill habitats get beaked snouts, mottled or rayed green-brown upper-shells, paddle-limbs, scale-tethered eyes and yellow lower-shells.

Critically endangered hawksbill sea turtle swims over a threatened elkhorn coral (Acropora palmata) in Virgin Islands National Park, St. John, U.S. Virgin Islands; Jan. 29, 2008: Caroline Rogers/U.S. Geological Survey, Public Domain via USGS

North American hawksbill habitats attach to distribution ranges in shallow coastal waters with rocky bottoms, coral reefs and mangrove-bordered bays and estuaries in the Atlantic and Pacific Oceans off the United States.

Hawksbills bear their common name for hawk-beaked snouts, the subspecies names Atlantic and Pacific hawksbills and the scientific name Eretmochelys imbricata (oar tortoise [with] overlapping [plates]). They carry the subspecies names Eretmochelys imbricata imbricata off the east coast and Eretmochelys imbricata bissa (oar-limbed tortoise [with] overlapping [scutes] double) off the west coast. Carl Linnaeus's (May 23, 1707-Jan. 10, 1778) descriptions in 1766 and Wilhelm Peter Eduard Simon Rüppell's (Nov. 20, 1794-Dec. 10, 1884) in 1835 dominate scientific designations.

Atlantic and Pacific hawksbill sea turtle life cycles expect nesting beaches and shallow waters with aquatic invertebrates, especially toxic sponges, whose toxins enter into hawksbill tissue.

April through November and September through February fit into hawksbill sea turtle life cycles as respective offshore breeding season months for Atlantic and Indian Ocean subspecies.

Atlantic and Pacific hawksbills get around on clawed paddlelike limbs over coral reefs, rocky bottoms and sandy shores and by floating, large seaweed mats over water. Aquatic and coastal lifestyles herald traumatic stress when Atlantic and Pacific hawksbills happen into shrimp nets, near land-located or water-reflected lights or onto turtle product hunters. Human interference for eggs, flesh, oils, shells, trophy parts and turkey soup calipees and introduced species incline otherwise balanced food chains and food webs toward irreplaceability.

Breeders, collectors, off-shore drillers, polluters and predatory estuarine crocodiles, ghost crabs, groupers, gulls, octopuses, raccoons, rats, requiem sharks and tiger sharks jeopardize North American hawksbill habitats.

Atlantic and Pacific hawksbills keep to shallow coastal waters during mating seasons because eastern and western coastlines know Mid-Atlantic, New England and southern California nesting-friendly beaches.

Females lay 50 to 200-plus leathery-shelled, spherical eggs 1.5 inches (38 millimeters) in diameter two or more times per mating season in 2-foot- (0.61-meter-) deep chambers. Hatchlings 8 to 11 weeks later must maneuver through multi-layered sand to move over open, sandy stretches into coastal waters and onto floating, large seaweed mats. Brown algae, comb jellies, crustaceans, fish, jellyfish, molluscs, Portuguese man-of-wars, sea anemones, grasses, sponges and urchins, shrimp and squids nourish omnivorous (everything-eating) Atlantic and Pacific hawksbills.

North American hawksbill habitats offer season-coldest coastal temperature ranges, northward to southward, from minus 15 to 35 degrees Fahrenheit (minus 26.11 to minus 1.66 degrees Celsius).

Continental shelves, hard-bottomed subtropical and tropical waters no deeper than 60 feet (18.28 meters), sea island lagoons, sponge-rich reefs and shoals promote Atlantic and Pacific hawksbills.

Twenty-five to 36 inches (63.5 to 91.44 centimeters) and 100 to 150 pounds (45.36 to 68.04 kilograms) queue up as mature hawksbill total lengths and weights. Adults reveal dual-paired pre-frontal scales between eyes, mottled or ray-patterned green-brown upper-shells with overlapping scutes, 4 costal scutes, 4 bridge scutes, paddle-like limbs and yellow lower-shells. Atlantic and Pacific adults and all juveniles respectively sport near-straight-sided, rear-tapering, shield-shaped upper-shells semi-keeled except the last 4 vertebral scutes; heart-shaped, continuously keeled upper-shells; two-ridged lower-shells.

Mottled, ray-patterned green-brown upper-shells with beak-like snouts, 4-scuted bridges, overlapping scutes, paddle-like limbs, scale-tethered eyes and yellow lower-shells, semi-concave if male, traverse North American hawksbill habitats.

Critically endangered hawksbill sea turtle (Eretmochelys imbricata) hides under boulder in U.S. Virgin Islands; March 18, 2006: Caroline Rogers/U.S. Geological Survey, Public Domain via USGS

Acknowledgment

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

Image credits:

Critically endangered hawksbill sea turtle swims over a threatened elkhorn coral (Acropora palmata) in Virgin Islands National Park, St. John, U.S. Virgin Islands; Jan. 29, 2008: Caroline Rogers/U.S. Geological Survey, Public Domain via USGS @ https://www.usgs.gov/media/images/endangered-red-hawksbill-sea-turtle-swims-over-threatened-elkhorn-coral-virgin-islands

Critically endangered hawksbill sea turtle (Eretmochelys imbricata) hides under boulder in U.S. Virgin Islands; March 18, 2006: Caroline Rogers/U.S. Geological Survey, Public Domain via USGS @ https://www.usgs.gov/media/images/hawksbill-sea-turtle-eretmochelys-imbricata

For further information:

Aardema, J.; S. Beam; J. Boner; J. Bussone; C. Ewart; I. Kaplan; K. Kiefer; S. Lindsay; E. Merrill; W. Moretz; J. Roberts; E. Rockwell; M. Reott; J. Willson; A. Pickens; W. Guthrie; A. Young; Y. Kornilev; W. Anderson; G. Connette; E. Eskew; E. Teague; M. Thomas; and A. Tutterow. "Atlantic Hawksbill Eretmochelys imbricata." Herps of NC > Amphibians and Reptiles of North Carolina > Turtles.
Available @ https://herpsofnc.org/atlantic-hawksbill/

Babcock, Harold L. (Lester). 1919. "Eretmochelys imbricata (Linné)." The Turtles of New England; With Sixteen Plates. Monographs on the Natural History of New England; Memoirs of the Boston Society of Natural History, vol. 8, no. 3: 342-345, Plate 19. Boston MA: Boston Society of Natural History.
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/12636545
Available via Internet Archive @ https://archive.org/stream/turtlesofnewengl00babc#page/342/mode/1up

Catesby, Mark. 1754. "Testudo caretta, The Hawks-Bill-Turtle." The Natural History of Carolina, Florida, and the Bahama Islands: Containing the Figures of Birds, Beasts, Fishes, Serpents, Insects and Plants: Particularly the Forest-Trees, Shrubs, and Other Plants, Not Hitherto Described, or Very Incorrectly Figured by Authors. Vol. II: 39. London, England: C. Marsh and T. Wilcox, MDCCLIV.
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/13414272

Holbrook, John Edwards. 1840. "Chelonia imbricata -- Linnaeus." North American Herpetology; Or, A Description of the Reptiles Inhabiting the United States. Vol. IV: 49-53. Philadelphia PA: J. Dobson.
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/3682742

La Cépède, M. le comte de (Bernard Germain Etienne de La Ville sur Illon); Georges Cuvier, Baron; A.-G. (Anselme-Gaëtan) Desmarest. 1881. "Le Caret." Histoire Naturelle de Lacépède: Comprenant les Cétacés, les Quadrupèdes Ovipares, les Serpents et les Poissons. Tome I: 137. Paris, France: Furne, Jouvet et Cie; Jouvet et Cie, Successeurs, MDCCCLXXXI.
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/16016475

Linnaeus. 1766. "2. Testudo imbricata." Systema Naturae per Regna Tria Naturae, Secundum Classes, Ordines, Genera, Species, cum Characteribus, Differentiis, Synonymis, Locis. Tomus I: 350. Editio Duodecima, Reformata. Holmiae [Stockholm, Sweden]: Laurentii Salvii [Laurentius Salvius].
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/42946546

Rüppell, Eduard. 1835. "Caretta bissa. Rüppell." Neue Wirbeltiere zu der Fauna von Abyssinien gehörig entdeckt und beschrieben. Amphibien: 4-7. Frankfurt am Main, Germany: Siegmund Schmerber.
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/37140294

"Seaturtles (Cheloniidae)." Pages 85-87. In: Grzimek's Animal Life Encyclopedia, 2nd edition. Volume 7, Reptiles, edited by Michael Hutchins, James B. Murphy, and Neil Schlager. Farmington Hills MI: Gale Group, 2003.

Sonnini, C.S. (Charles-Nicolas-Sigisbert); P.A. (Pierre André) Latreille. 1801."La Tortue Caret, Testudo imbricata." Histoire Naturelle des Reptiles, Avec Figures Dessinées d'après Nature. Première Partie: Quadrupèdes et Bipèdes Ovipares. Tome premier: 50-53. Paris, France: Imprimerie de Crapelet, An X (September 1801-September 1802).
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/3688562

Uetz, Peter. "Eretmochelys imbricata (Linnaeus, 1766)." The Reptile Database.
Available @ http://reptile-database.reptarium.cz/species?genus=Eretmochelys&species=imbricata