#Hesperornis regalis

[ppaleoartistgallery]

#Paleostream 14/06/2025

here's today's #Paleostream sketches!!!

today we sketched Hesperornis (i drew H. regalis), Asiatyrannus, Manis palaeojavanica, and Khankhuuluu

[a-disaster-piece]

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Hesperornis, my beloved.

Work in progress underpainting for Hesperornis regalis. In the Late Cretaceous (83.5 to 78 million years ago) on the sun soaked shores of the Western Interior Seaway, a large body of water that ran along the interior of the North American Continent, a colony of large flightless birds bask on the rock strewn coastline of what humans would later call Kansas.

Much like modern loons their legs are sufficiently powerful tools that allow them to not only paddle on the surface of the water but dive beneath its surface to catch fish in their tooth-filled beak, but also like loons their legs were likely not well adapted for land. It is thought that they likely pushed themselves around on on their bellies similar to modern pinnipeds like seals and walruses.

They were large in comparison to more modern sea birds even dwarfing the recently extinct Great Auk, which stood around 2.75 feet, H. regalis could reach up to 5.9 feet in length. Their size was likely a benefit when contending with some of the nastier denizens of the Cretaceous seas, not only would they have to contend with a whole host of sharks but also monsterous fish like Xiphactinus, capable of reaching a length of up to 20 feet and large marine reptiles like Plesiosaurs, as well as contending with diving Pteranodons from above and predatory dinosaurs from the land.

Hesperornis had virtually no wings to speak of and had to navigate their world with nothing but a pair of powerful legs and a toothy set of jaws, but they were still relatively successful despite that, as many of the traits that aided them in their success have recurred again in other species thanks to convergent evolution.

[libelelle]

Low key disappointed that im not thinkjng about my au rn but birdie : ) birdie with teeth and claws and no common name

[regaliceratops]

Hesperornis regalis was a large aquatic bird from Late Cretaceous North America. Its lineage may have been one of the first bird groups to re-evolve flightlessness, as Hesperornis had extremely reduced arm bones and likely used webbed or lobed toes to propel itself through the water.

[veloci-raptor]

A Day in Niobrara

1. Hesperornis regalis 2. Nyctosaurus gracilis 3. Pteranodon longiceps 4. Claosaurus agilis 5. Niobrarasaurus coleii 6. Gillicus arcuantus 7. Enchodus petrosus 8. Platecarpus tympaniticus 9. Dolichorhynchops osborni 10. Protostega gigas 11. Clidastes prophython 12. Tylosaurus proriger 13. Bonnerichthys gladius 14. Ptychodus mortoni 15. Styxosaurus snowii 16. Xiphactinus audax 17. Cretoxyrhina mantelli

[ironhidearcee]

Inspired by @albertonykus‘s 50 Dinosaurs Meme.

(Answers below the break) 1) Diplodocus hallorum 2) Allosaurus fragilis 3) Tyrannosaurus rex  4) Halszkaraptor escuilliei 5) Styracosaurus albertensis  6) Parasaurolophus walkeri  7) Mononykus olecranus  8) Kelenken guillermoi  9) Gastornis gigantea 10) Butorides striata  11) Hesperornithoides miessleri  12) Iguanodon bernissartensis  13) Archaeopteryx siemensii  14) Kulindadromeus zabaikalicus  15) Giraffatitan brancai  16) Corvus splendens  17) Stegosaurus stenops  18) Deinocheirus mirificus  19) Citipati osmolskae  20) Microraptor zhaoianus  21) Psittacosaurus sp.  22) Anzu wyliei  23) Hesperornis regalis  24) Miragaia longicollum 25) Plateosaurus engelhardti  26) Europasaurus holgeri  27) Edmontosaurus annectens  28) Borealopelta markmitchelli  29) Triceratops prorsus  30) Kosmoceratops richardsoni  31) Dilophosaurus wetherilli  32) Baryonyx walkeri  33) Yutyrannus huali  34) Sinocalliopteryx gigas  35) Yi qi  36) Nigersaurus taqueti  37) Deinonychus antirrhopus  38) Pachyrhinosaurus lakustai  39) Herrerasaurus ischigualastensis  40) Ankylosaurus magniventris  41) Coelophysis bauri  42) Sauropelta edwardsorum  43) Majungasaurus crenatissimus  44) Neovenator salerii  45) Chilesaurus diegosuarezi  46) Elaphrosaurus bambergi  47) Apatosaurinae indet. (AMNH 460) 48) Acrocanthosaurus atokensis 49) Muttaburrasaurus langdoni  50) Confuciusornis sanctus 

[carnegiemuseumnaturalhistory]

“Toto, I've a feeling we're not in Kansas anymore.”

This scene represents a moment in time 83 million years ago, in what is now the state of Kansas, which was covered by a body of water known as the Western Interior Seaway and populated by diverse, prehistoric marine life. In this diorama near Dinosaurs in Their Time, an agile marine reptile, Dolichorhynchops bonneri, dives after the penguin-like bird, Hesperornis regalis.

[codex-ebervalianus]

Hesperornis regalis

[thecreaturecodex]

Boobrie

“109--Hesperornis regalis” © deviantArt user “Green Mamba”. Accessed at their deviantArt page here

[The boobrie is a monster I first learned about in old-school D&D books, but was pleasantly surprised to discover it has a folkloric basis. Gygax described it like a crane or stork. Most of the Google Image Search results for boobrie turn up terror birds. But the idea of a giant seabird that bellows, wails and mimics livestock got me thinking loons. And what prehistoric animal is reconstructed as being like a giant terrifying loon? Hesperornis, a toothed bird from the Niobraran formation of Kansas. So my take is decidedly Hesperornis inspired (although much bigger)]

Boobrie CR 5 N Magical Beast An enormous bird swims past, its wings reduced to flaps and its clawed toes covered in fleshy lobes. Its hooked beak is as long as a man’s arm.

Boobries are enormous, monstrous relatives of the common loon. Those mundane birds are well-known for their bizarre and eerie cries, but the boobrie takes this vocal expertise to unparalleled levels, capable of both imitating the sounds of other creatures and creating a pulse of powerful sonic energy. Boobries use their mimicry to hunt—they lure creatures such as seals and dolphins to striking distance by copying their vocalizations. Barges and ships carrying livestock are likely to be trailed by a boobrie for days until it learns how to properly mimic a sheep, goat or cow. Any curious animals (or sailors) that approach the edge of the ship to investigate the bizarre noise will then be dragged overboard and consumed by the immense bird.

Boobries are equally at home in salt and fresh water, preying on fish, sea mammals and creatures drinking on the shoreline. Like ordinary loons, they are clumsy on land, dragging themselves on their bellies and pushing themselves with back-set legs. They are solitary creatures except during mating season. Male boobries compete over females not with violence but with displays of mimicry—the bird that creates the widest and most impressive variety of sounds will earn mating rights. Male and female boobries care for their chicks with equal fervor and will defend their nests to the death. A boobrie grows to 20 feet long and weighs 1,200 pounds. Their feathers are a glossy black with white accents and their eyes are vivid shades of red, orange or yellow.

Boobrie             CR 5 XP 1,600 N Huge magical beast Init +1; Senses darkvision 60 ft., low-light vision, Perception +6 Defense AC 17, touch 9, flat-footed 16 (-2 size, +1 Dex, +8 natural) hp 52 (7d8+14) Fort +7, Ref +6, Will +3 Offense Speed 20 ft., swim 60 ft. Melee bite +9 (2d6+6 plus grab) Space 10 ft.; Reach 10 ft. Special Attacks capsize, roar, swallow whole (AC 14, 5 hp, 2d6+4 bludgeoning) Statistics Str 18, Dex 13, Con 15, Int 4, Wis 13, Cha 11 Base Atk +7; CMB +13; CMD 24 Feats Dodge, Mobility, Skill Focus (Bluff), Spring Attack Skills Bluff +10, Perception +6, Stealth +6, Swim +15; Racial Modifiers +4 Bluff, +4 Stealth SQ hold breath, sound mimicry (animal sounds) Ecology Environment cold aquatic Organization solitary or pair Treasure incidental Special Abilities Roar (Su) As a standard action once every 1d4 rounds, a boobrie can give an enormous bellow. All creatures within 60 feet of a roaring boobrie take 3d6 points of sonic damage and must succeed on a DC 15 Fortitude save or be stunned for 1 round. The save DC is Constitution based.

[artscult]

GIGANTIC DIVER, HESPERORNIS REGALIS, CRETACEOUS PERIOD - high resolution image from old book.

[nemfrog]

Hesperornis regalis, Late Cretacean aquatic flightless bird. Odontornithes: a monograph on the extinct toothed birds of North America. 1880.

[palaeornithology]

Hesperornis regalis

My first piece of digital palaeoart, based on a drawing I did a few months ago. The plumage is based on a Common Merganser’s.

H. regalis, described by O. C. Marsh in 1872, was a specialised and superficially loon-like diving bird from North America, at a time that much of the continent was hidden underneath a subtropical shelf sea. It would have used its long beak - lined with small sharp teeth - to catch fish in the water column. In turn, it would have fallen prey to the huge array of large predators that shared the water with it, including Xiphactinus audax and Tylosaurus proriger. 

EDIT: this is not a correct reconstruction! I have since learnt that Hesperornis would have possessed a compound rhamphotheca made up of multiple plates that did not cover the whole of the mouth as in modern birds. The teeth would not have been visible when the mouth was closed.

[thecoffeeisblack]

Final for Hesperornis regalia. Discovered in 1871 by Othniel Charles Marsh while on on expedition in Kansas, the remains lacked a skull but Marsh could see that it was a large flightless sea bird with strong legs, he christened them Hesperornis regalis, roughly meaning "Regal Western Bird." The following year he returned and found more remains, this time with a partial skull that revealed a beak lined with teeth, Marsh would later remark in publication that the remains of this and those of another toothed bird, Icthyornis, "does much to break down the old distinction between Birds and Reptiles." Hesperornis was a large sea bird measuring 5.9 feet in length, living on the shores of an inland sea during the Late Cretaceous (83.5 to 78 million years ago) it was built for diving in some of the most dangerous environments in the history of the earth, having to contend with predatory dinosaurs on land, large pterosaurs in the air, and huge sharks, fish, and marine reptiles in the water. They are thought to have been cumbersome on land like modern loons, but strong swimmers. The waters in which they swam were subtropical to tropical, a much warmer environment than today. 9 other species have been found and assigned to the genus, with 8 coming from rocks in North America and 1 from Russia.

[petitepaleoartist]

new #Paleostream sketches as per the usual program

#Paleostream 14/06/2025

here's today's #Paleostream sketches!!!

today we sketched Hesperornis (i drew H. regalis), Asiatyrannus, Manis palaeojavanica, and Khankhuuluu

[thecoffeeisblack]

Color work in progress underpainting for Hesperornis regalis. Color and patterning are a based on a combination of a Common Loon, a Double Crested Cormorant, and a Great Crested Grebe.

[thecoffeeisblack]

New tshirts, stickers, mugs, and more are available on my @teepublic shop! Let Hesperornis regalis dive into your heart by picking something up. 

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teepublic.com/user/coffeeblack