Greenland Sleeper Shark Natural History Illustrations and Photographs

Summary: Icelanders and Greenland sleeper shark natural history illustrations respectively know all about kæstur hákarl and little of live specimens' life cycles.

Greenland sleeper shark, between Alvin and Nantucket canyons, undersea features 100-plus miles south of Nantucket Island; Aug. 16, 2013: Northeast U.S. Canyons Expeditions 2013, Public Domain, via NOAA Ocean Exploration and Research (OER)

Greenland sleeper shark natural history illustrations and photographs act as artistic analyses of behavioral patterns, distribution ranges, life cycles and physical appearances of sea fishes that Icelanders appreciate as fermented shark meat.

Greenland sleeper sharks, preferentially of all sleeper shark species, become kæstur hákarl ("fermented shark" meat) through a violent beating away of bodily fluids and temporary burial. They carry as common names gray, ground and gurry sharks for body color, feeding niches and scavenging preferences and sleeper sharks for slow, sluggish swimming styles. The scientific name Somniosus microcephalus describes the Squaliformes shark order member's "sleepy, little head," due to docile deportment around parasitic copepods, potential prey and predatory fishers.

Scientific explanations by Marcus Elieser Bloch (1723-Aug. 6, 1799) and Johann Gottlob Theaenus Schneider (Jan. 18, 1750-Jan. 12, 1822) encourage Greenland sleeper shark natural history illustrations.

Greenland sleeper shark natural history illustrations since 1801, photographs since 1995 and videos since 2003 furnish few and far-between facts concerning frequenters of cold, remote depths.

Bloch and Schneider gave the general distribution ranges of their Greenland sleeper shark specimen of undescribed provenance as Habitat in mari glaciali ("Habitat in glacial seas"). Distribution maps in the 21st century have Greenland sleeper sharks in the Arctic Ocean off northeastern Canada, northeastern and northwestern Greenland, northeastern Norway and northwestern Russia. They include the North Atlantic ocean off eastern Canada, the eastern United States through Massachusetts, eastern Iceland, Ireland, United Kingdom and Europe from France through Norway.

Greenland sleeper shark natural history illustrations and photographs sometimes jumble food chains into the Somniosidae family members' journeys between continental shelves and slopes and inshore zones.

Greenland sleeper shark distribution ranges keep closer to brackish and shallow ocean water surfaces during winter's decreasing temperatures and to ocean floors during summer's rising temperatures.

Their life cycles lead Greenland sleeper sharks to depths 7,217.85 feet (2,200 meters) below the surface and to temperatures below 32 degrees Fahrenheit (0 degrees Celsius). Greenland sleeper sharks mix deep-water, low-profile, summertime and fall movements between July and September and fall, wintertime and springtime high-profile, near-surface movements between October and May. They need amphipods, brittle stars, capelins, chars, crabs, eels, haddock, halibuts, herring, jellyfishes, lumpfishes, narwhals, redfishes, salmon, sculpins, seabirds, seals, skate, snails, squid, urchins and wolfishes.

Greenland sleeper shark natural history illustrations and photographs offer blue-, brown-, purple-gray 11- to 21-foot- (3.35- to 6.40-meter-) long, 1,543.24- to 2,248.72-pound (700- to 1,020-kilogram) bodies.

Physically and sexually mature females, possibly 150 years old or more, produce generally, maximally or minimally 10 live-birthed 14- to 17-inch- (3.56- to 43.18-centimeter-) long embryos.

Blunt-snouted, cone-headed, suctoral-mouthed, torpedo-bodied adults queue up 48- to 53-cusped lower jaws, paddle-like pectoral fins, ridged tail fins, small gill slits and two spineless dorsal fins. Breeding and birthing behaviors and months remain as mysterious as navigation and predation, despite cornea-attached, cornea-damaging, vision-destructive Ommatokoita elongata parasites, through olfactory openings and sound detection. Annual 0.19- to 0.39-inch (0.5- to 1-centimeter) growth rates and radiocarbon-dated eye lens crystals suggest 272- to 512-year-old Greenland specimens as the world's longest-lived, second-largest shark.

Photographs and publications, not Greenland sleeper shark natural history illustrations, respectively treat transformations into kæstur hákarl and buoyancy and deep-water tolerances through trimethylamine N-oxide and urea.

distribution map for Greenland sleeper shark (Somniosus microcephalus): Chris_huh, CC BY SA 3.0 Unported, via Wikimedia Commons

Acknowledgment

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

Image credits:

Greenland sleeper shark, between Alvin and Nantucket canyons; Aug. 16, 2013: Northeast U.S. Canyons Expeditions 2013, Public Domain, via NOAA Ocean Exploration and Research (OER) @ https://oceanexplorer.noaa.gov/okeanos/explorations/ex1304/dailyupdates/ex1304daily.html

distribution map for Greenland sleeper shark (Somniosus microcephalus): Chris_huh, CC BY SA 3.0 Unported, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Somniosus_microcephalus_distmap.png

For further information:

Benz, George W. "Greenland Shark Somniosus microcephalus." In: Michael Hutchins, Dennis A. Thoney, Paul V. Loiselle and Neil Schlager, eds. Grzimek's Animal Life Encyclopedia. Second edition. Volume 4, Fishes I: 156-157. Farmington Hills, MI: Gale Group, 2003.

Blochii, M.E.; Jo. Gottlob Schneider. 1801. "29. [Squalus] microcephalus." Systema Ichthyologiae Iconibus ex Illustratum. Post Obitum Auctoris Opus Inchoatum Absolvit, Correxit, Interpolavit: 135. Berolini [Berlin, Germany]: Sumtibus Auctoris Impressum et Bibliopolio Sanderiano Commissum.
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/5475232
Available via Internet Archive @ https://archive.org/stream/meblochiidoctori00bloc#page/135/mode/1up