The hesperornithines are very interesting birds in a variety of ways. They are the last of the basal Ornithuromorpha. Hespies as they are commonly called, were the first dinosaurs to successfully enter the marine niches in a big way. They are known from Early Cretaceous deposits, some of the fossils indicating flightlessness having independently evolved several times. Having entered the seas, Hespies were similar to the pinnipeds of HE. They seem to have only returned to land to lay eggs or perhaps haul out for sleep.
On HE, they died out along with all other birds outside of Neornithines. Spec of course, is different. These toothed birds continued into the Paleogene, albeit in reduced numbers. They disappear from the fossil record during the PETM; reappearing in the late Eocene in the form of *Phocavis*. This initial reappearance lead to a nearly worldwide distribution. The Phocaviids even were found in the southern seas, traditional home of the penguins. They had a very long temporal range, the last members fading from the record in the mid Pliocene in southern Africa.
Phocaviids have only recently been studied in detail. The prompting came from a Paleocene bed of archaic hesperornithine oo-fossils. This bed was very interesting in showing large numbers of eggs laid in sand and overlain by repeated volcanic pyroclastic flows. The reason for such interest lays with the fact that modern hesperornithines are not known to lay eggs in beach sand, indeed they do not construct nests at all. For quite some time, it had been assumed that modern hesperornithines were directly descended from sea-going archaic Maastrichian/Paleocene ancestors.
The revised studies have shown marked contrasts. Modern hespies do belong to the order, but they are not closely related to any of the known archaic species. The phocaviids instead seem to have descended from flying members of the clade. Close study of phocaviids show primitive features in their wings, dentition and skeleton compared to archaic hesperornithines. However, the braincase shows massively advanced features such as development of the neocortex, further developments of the optic and auditory bulla which are completely unknown in archaic hesperornithines. This was a revelation, which is being further supported by fossils that are yet in press. The main guise of this interest was the difference between modern hespies and their archaic cousins with regards to reproduction.
Modern hespies do not lay eggs in sand and abandon their young, they don’t even construct nests. These birds retain eggs within their bodies until they hatch. These archosaurs, like the qurry laurasiornithopods and heterodontosaurs; have found loopholes. Archosaurs and Testudines (turtles) cannot retain eggs like many other Sauropsids because of the unique properties of the egg shells. However, once the eggs are laid, they can be transferred into a pouch for safe keeping. The qurry ornithischians have independently developed throat brooding. The modern hesperornithines have developed cloacal pouches to hold their eggs in. These posterior pouches are richly developed with capillaries and frequently open their sphincter muscles to allow fresh oxygen to be exchanged. The result is that hespies mate out at sea, with the females beaching themselves once the egg or eggs are laid; pushing themselves across gravel, sand, rock or ice to incubate for up to three months.
Both seaguins and penguins suddenly shoot up in size and diversity from the late Miocene onwards. It seems the more ancient phocaviids may have filled niches that the reigning warm-water mosarks, the later duckotters and abysmal walducks could not. Whatever the case, the phocaviids dwindled to obsolescence by the Ice Ages. Modern Hespies are quite common in the seas of the northern hemisphere, with a few species found south of the equator on tropical islands abutting cold upwelling abysmal waters in colonies shared with their penguin counterparts. One species is cosmopolitan.
Gharihingas *Odontanhingidae*
Not all modern hesperornithines are flightless marine swimmers, the ancient gharihingas are flighted birds found across Africa, Eurasia and Australia. They fill a niche similar to the predominately New World ebergs and HE’s loons, cormorants and especially anhingas. This clade is ancient, molecular and morphological studies indicate that they separated from most hesperornithines probably by the Turonian.
Gharihingas are quite common in tropical wetlands, with a few migratory species. They are strong fliers, excellent swimmers, but are poor walkers due to their splayed legs. Their characteristic beaks retain teeth in both skull and maxilla; as well as being usually long, almost a third of body length. Most species nest in tree hollows or construct floating raft nests where they hatch their 2 to 6 precocial young. Incubation is long, and parental care of the offspring is rather short. The young are usually capable of fledging within a month of hatching. Migratory species usually abandon the chicks after hatching.
Blue Cheek Gharihinga *Odontanhinga mordax*
The blue cheek gharihinga measures about 75 cm in length. It lives along the large rivers and lakes of Europe, southern Siberia and China. Remarkably, the Siberian populations migrate to India for the winter, while some European populations head for the Nile delta.
These waterfowl are not the first to arrive in spring, but they are never the last. Adults court each other in large polyamorous gatherings. The females retreat to nest in tree hollows or dense bank vegetation within close distance of the lakes, rivers or ponds they choose. The precocial young hatch after an incubation of some 40 to 50 days. The mother promptly abandons them to their fate. The clutch scramble their way out of the nest and hide in tall reeds during the day. They are already expert swimmers, diving and foraging together until they fledge in a month or so.
Seaguins *Sednaornithidae*
The modern day flightless hesperornithines share common ancestry with the phocaviids. However; skeletal morphology shows they split from them around 45 mya during the beginning of the Cenozoic cooling cycles. Fossils are rare, only showing up during the Miocene. They are of scrapes usually; showing animals rarely larger than an average duck. The Pliocene is quite different, with an increase in size and ecotypes. The Artic and North Atlantic Oceans have long been their centers of diversity since the late Miocene. That pattern has diverged with the rise of large numbers of North Pacific species since the earliest Pleistocene. Seaguins today range throughout the northern Oceans and Seas. A few species may be found in Equatorial waters as far south as the Hawai’is and the Galapagos; where they meet their distant penguin relatives.
Seaguins share with their phocaviid relatives, the intriguing trait of incubation within a cloacal pouch. Some phocaviid fossils show this trait as far back as the late Eocene, indicating both clades have derived this from their last common ancestor. The implications are both staggering and presently obvious.
Keeping the egg or eggs within a sealed pouch close to the body allows for rapid incubation. The capillaries and oxygen exchange by “burping” or “farting” the pouch gives the mother extended feeding opportunities within shallow waters if needed. The chick can be born in a fairly neotonous and yet precocial state. They are loaded with yolk fats, allowing them to remain in safe coves and estuaries near rookeries for weeks or months. This period also allows for extensive teaching by mother and/or relatives before finally heading out to sea. This has been a very successful strategy, resulting in more than 40 to 50 species. Like their predecessors; they swim the seas with permanently splayed legs. Their four toed feet adorned with lobed webbing. Well oiled coats and powerful muscles allow some species to reach speeds of more than 70 kph.
Sea Parrots and Sea Jars *Maripsittacinae*
The sea parrots and sea jars represent a good portion of the diversity of seaguins. More than 20 species are known. The two tribes are noticeable for having blubber layers up to six inches thick around their torsos. They are also known as “double-eggers”. Unlike other seaguins, females always lay two eggs within their uniquely divided cloacal pouch. Various species have different haul-out choices. Pacific and Atlantic species choose offshore islands. Arctic species are much like HE ringed seals in excavating snow caves for the duration of the incubation period.
The maripsittacines are intensively hunted by selkies and other seaguins. These gentle clam crackers and filter feeders have devised many strategies for survival, ranging from pods thousands strong to shy, solitary ice dwellers barely surfacing for a breath. Mortality is high, especially when young and most species see near-complete turn-over rates every 5 to 12 years.
Sea Parrots *Maripsittacini*
The sea parrots often spend their time in nearly vertical positions above the seafloor selecting various mollusks to crush between their jaws. Sea parrots share a niche similar to HE and Spec diving ducks; except on a much larger scale. Because they cannot apply suction like HE walrus, their crushing jaws are limited to specific clam and ammonite species. This has resulted in an ever spiraling increase in diversity of both sea parrots and especially clams. Spec sea clams and ammonites have ironically benefited from this evolutionary arms race with many new types invading niches far beyond their ancestors.
Some sea parrots stay close to shore, feeding in tidal pools or flats. Other species feeding in waters as deep as 500 feet. Various species are specialists; others generalize over many clam and ammonite species with similar shell densities and sizes. The Ice Age has only increased much of this diversity with niche squeezes and expansions. Sea parrots may actually be much more species rich than the currently recognized 20.
Walrooster *Odobenornis occinerator*
The walrooster is by far, the largest sea parrot species, weighing around the same as the much sleeker and longer empress seaguin. This is partly because of their rather heavy and robust bones, which help them dive; walroosters are also known to swallow stones for the same purpose.
These massive divers live in the arctic sea, feeding mostly on bottom-dwelling mollusks such as shellfishes, which they detach from rocks using their hooked beaks, and crush the shells with their impressive battery of teeth. They also occasionally catch crabs, but hardly ever even try chasing ammonites like their smaller and swifter cousins. There have also been reported cases of walroosters scavenging. It seems that with their powerful jaws and teeth they can crack the bones to get to the marrow, inaccessible to most predators.
Walroosters can often be seen in large numbers resting on arctic rocky beaches or ice floats. Using their hooked bills and powerful legs to haul their great mass ashore. The males have a very loud and recognizable voice, used during the mating season and related social disputes, which resembles the crowing of a cock. Not all walroosters are strictly artic animals. Southern regions such as New England and Iceland harbor large brooding colonies of walroosters. Walrooster eggs rival those of grassbags in size.
Atlantic Sea Parrot *Maripsittacus atlanticus*
The Atlantic sea parrot is a generalist species. It is average size for the clade, at around 2.5 meters and 200 kilos in weigh. They may be found in a wide variety of near shore environs from tidal flats digging in shallow mud, out to depths of 100 feet. Favored prey are clams between 200 grams to 1 gram in size and similar sized ammonites easily caught. A recent division has raised the closely related Bering sea parrot *Maripsittacus stelleri* to species status. Both species tend to have large rookeries of hundreds to thousands on off-shore islands shared with jarrks and duckotters.
Sea Jars *Maricaprimulgini*
The sea jars very much resemble nightjars with their wide mouths lined with innumerable stiff feathers and lamellae to catch zooplankton and baitfish. They often follow baleen squid to large concentrations of food. Sea jars have also been known to cooperate with jarrks, large ammonites, teleosts and even certain sharks and mosarks to concentrate bait balls of fish or crustaceans. Such behavior is necessary, since the 8 known species of sea jars are all deep ocean wanderers, visiting various upwelling nutrient hotspots.
Knight Jar *Maricaprimulgus dracophagus*
Named with tongue in cheek for their feeding habits. Knight jars are deep diving seaguins who sweep huge numbers of immature sea dragonflies into their craws. Knight jars have a huge cosmopolitan range across the cooler to tropical waters of the northern hemisphere. A Galapagos colony is known. They are generalist predators of most sea dragonfly species, but will also take Argonautoids and join bait ball congregations if they come across them.
Knight jars are primarily nocturnal feeders, they meet the rise of sea dragonflies every night. These birds are also known for their grisly habit of snatching pirhanakeets during their main feeding and breeding season. While the tiny penguins are busy devouring ample numbers of exhausted male baleen squids; the knight jars zip through their feeding frenzies. A single knight jar, at nearly three meters and 300-400 kilos can take up to 10 pirhanakeets. These seaguins are lightning quick and can dive to depths far below the terror penguins’ perceptions within moments. Besides, the pirhanakeets are too busy gorging themselves on cephalopod flesh.
Speckled Sea Jar *Sednaornis geladus*
The speckled sea jar lives permanently below ice in waters between 30 to 500 feet deep. This is the smallest of sea parrots at less than a meter and 40 kilos. These birds have very thick, ragged bills to allow them to saw away at the thinnest spots of ice within their territories. They are much more generalist in their diets, taking winter slowed fish and ammonites under the ice as well as diving to depths of 500 feet to crunch shellfish. Their whisker like bill feathers are exquisitely developed to allow them to sort out prey items.
These animals form snow caves for their two offspring. Like HE ringed seals, the female birds nestle for much of the 3 week incubation period; diving into the sea only when polar draks burst through. Several caves may be found throughout her territory. Still, up to 40% of the hatched chicks may fall prey to the draks. Also, when ice break up occurs, selkies take their share.
True Seaguins *Dagonavinae*
The 10 to 15 species of true seaguins are primarily fish eaters, with a few exceptions. Most seaguins are very large animals, average 4 meters in length and some 300 to 500 kilos. These are deep water birds, closely resembling many dolphins in their long distance migrations. Unlike the sea parrots and sea jars; females beach themselves only when hatching is imminent. The young are quite precocial, being lead down into protected coves and grottos for the first two to five weeks before they are allowed to join the larger flock on their never ending search for food.
Seaguins tend to have temporary monogamous associations during the breeding season. Successful males might have up to three mates. The reverse is true for some species, with one gravid female having two males providing for her and their shared clutch of up to three eggs.
Seaguins *Delphigavini*
After the speckled sea jar, these hespies were among the first described seaguins. The deep ocean fishers that sport among walducks, mosarks, jarrks and sea jars. They spend most of their lives at sea, coming ashore only for a brief month to hatch their eggs and shelter their young before racing back out to sea with the chicks in tow. Little is known of these birds. They mysteriously appear in the thousands to herd fish and cephalopods in enormous bait balls and quickly disperse again when the glut is over.
Little is known of these animals; including their rookeries. They have several species in northern hemisphere oceans. One species is known from the Mediterranean and a possible rare, separate species found in the Indian Ocean.
Hylekki *Delphigavus balticus*
The specific nomer is somewhat misleading, since these birds are also known from carcasses and flocks in Iceland and off the Faroes. Unlike most true seaguins, hylekkis tend to nest in large rookeries alongside other sea critters like their maripsitticinine relatives and jarrk selkies.
This has been a boon, allowing spexplorers to see they have a polyandrous mating structure.
Females have one to two tiercel; the males, who are around three quarter of the female’s size, will hunt for her while she is gravid with up to 4 eggs. Surprisingly, the female seems not to make land-fall until well after egg laying. The chicks hatch within a week. The 300 kilo males heave ashore to their 400 kilo mate time after time for three weeks before the chicks scramble behind their mother into the surf. The whole family may remain near shore for another week before shooting out into the deep sea to parts still unknown.
Tuna bird *Delphigavus thunnoides*
The tuna bird is probably the fastest of the hespies. Top speeds of 70 kph have been reliably recorded. They literally rocket out of the surface to heights of 20 feet in the pursuit of their main prey, bait fish and squid. These enigmatic north Pacific birds are little known. They seem to travel along the Pacific Gyre from warmer waters to the south up to the frigid Bering seas. Only one small rookery has ever been discovered in the Priblof islands. It seems that a single male mates with several females and has no further care for the offspring.
Tyrant loons *Orcavini*
The tyrant loons are a small tribe consisting of just two members. They have the unusual habit of beaching on ice floes or shallow sandbars when gravid. The young are hatched into open waters. Fish and ammonites are the primary prey of the lesser species; while the larger species seeks tetrapods. Both have short, broad beaks to allow them to crush prey with great force.
Blue tyrant loon *Orcavis velocinatans*
The blue tyrant loon is a common artic hespie. These generalist feeders mostly take fish and ammonites; but will also snap up the young of mammals and birds alike. At 2.5 meters and some 300 kilos, they are too small to threaten the majority of adult marine mammals and birds.
Blue tyrant loons are easily recognized by their stout bills and dappled coloration. The flanks flash vividly blue when caught by the pale artic summer light; the rest of the bird is a mottled white and dun blue coloration. This serves them well in all seasons. The blue tyrant loon remains quite close to the ice in all seasons. Females haul out for the incubation period while males hunt for food. Leads in the ice are sensed with their delicate hearing, allowing them to penetrate far north during especially warm years.
Polar draks are their principle predators. Nesting females live in matrilineal families that offer good protection. Even a starved drak will turn back at crushing tooth lined jaws. However, when leads close and trap flocks; they hope against hope that a polar drak will not discover their breathing hole or several of them may end up dragged up onto the ice with their throats torn out.
Like many other Spec marine denizens, blue tyrant loons may be found in Spec’s St. Lawrence River and Lake Ontario. There they feed on warm blooded prey such as selters and walrooster chicks.
Empress Seaguin *Orcavis regina*
The empress seaguin is the terror of the cold northern oceans. Murders of these birds have been known to tear apart kronosharks and chilled giant mosarks with impunity. At some seven meters and close to 4,000 kilos, they are the lords of the bitter frigid seas. They can be found across the cooler waters of the northern Atlantic and Pacific into the Artic. An Empress raising her unmistakable head above waters near a rookery provokes an instant reaction. That reaction may be a quick head raising or an all out race to higher beach. These extremely intelligent birds are totally in control of their realm and enjoy it.
Empress seaguins live in life-long monogamous pairs within matrilineal rookery flocks. They prey on all life in the sea, but prefer warm blooded animals. All their cousins are torn apart, as well as all unlucky mammals who stray into their jaws. Only the presence of giant mosarks in the tropics prevents them from taking over the oceans of the world.
During the breeding season, the murders find safe havens on sandbars in estuaries near large rookeries of their prey. The females lug their huge mass half ashore; digging out enough sand so their chests float easily in water while their hind ends remain beached. No known terrestrial predator has ever threatened these birds and lived to tell of it. A spexplorer saw a saber tyrant dragged to death by two sister empress. The whole flock ripped it apart and feasted. The eggs seemed not to suffer since the females were soon back ashore; stuffed by their mates with tyrannosaur flesh.
Empress seaguins have short, broad mouths much like their smaller kin. They also possess a hooked beak and a scooping bill like any raptor. Acting in concert, the tearing tip works with the shredding posterior teeth to yank away huge chunks of flesh. They do not roll like crocodiles to secure meat; instead, they hone keratin and tooth against gravel, driftwood and bone to razor sharpness.
Dagon *Dagonavini*
When spexplorers first arrived, they were divvied up into dozens of teams. One team doing paleontological work in some New Jersey late Pliocene shore beds recovered the enormous skull of a seaguin. Naming it after HE’s sperm whale *Physter macrodon*. The 2.5 meter skull was stored away and spoken of mainly in academic and Spec fan circles. Impressive, but regarded much like HE’s *Andrewsarchus* or *Daeodon*, an after thought monster of a close, but still by-gone era.
But a young mammalogist affectionately known as Coyote was diving off of Bermuda studying and filming an adolescent male striped walduck recently kicked out of his pod. He was preparing to tag the animal when a massive…thing rose up from the dark depths and slammed its 3 meter golden jaws around the hapless monotreme. Blood spattered and bloomed like squid ink. The poor man was less than two feet away from the pitiless eye of the monster.
Coyote was raised shaking from the sea. All that could be heard from him was “Dagon, Dagon!!!!”. Eventually he recovered. But the nomer stuck unofficially. Luckily, he had tagged the sea monster with the camera. This allowed more sane members of the expedition to observe the creature over several days. This results were surprising. This animal was a hespie; the largest ever known. They watched the female return to a shallow Bermuda island cove where she remained for the following days. The film tag frustratingly showed her hatching a chick before it went dead. The location was tracked, divers later recovered several eggshells; partially reconstructed, they showed an egg larger by far than any other tetrapod known in either timeline.
By this time Coyote had recovered and named the species *Dagonavis*, he spend the next few years searching for these mysterious birds and following their living patterns. It turned out that dagons were deep divers, hunting at depths of more than half a mile. Tagging and filming as well as dissection of beached specimens in Iceland showed a preference for cephalopods and fish, with some sharks and walducks occasionally present.
Ambergrans are the only cosmopolitan member of the hespies. They are found in all seas, but prefer the cooler latitudes, mostly heading into the tropics only when certain deep sea prey are massed for breeding. Their own breeding can be varied, but is primarily limited to cooler waters, where giant mosarks cannot go.
The modern seaguin tribe was christened after this monster; however, in one of those ironies, it turned out that the Pliocene *Physteravis* was close enough to the dagon to be regarded as an extinct representative of the genus. The dagon, also known as the ambergran; was rechristened *Physteravis marovum*.
Still, when the huge females cloak their eggs, they can no longer dive to great depths. Their ravening hunger turns to the supine prey close to the surface. Any reptile, mammal, or cephalopod unlucky enough to catch her eye or alert her ear will be torn apart for food in primal need to feed herself to care for her unhatched egg. Fear the dagon, for she rises with speed and jaws of death.
Ambergran….or Dagon *Physteravis marovum*
The ambergran must be the most magnificent of the already great hesperornithine clade.
Females reach over twelve meters and males are little smaller at nine to ten meters. The big females weigh up to 12,000 kilos lean and may be close to 16,000 kilos during the breeding season. Unlike all other hespies and indeed unlike all other archosaurs, the female ambergran remains out at sea for the duration of her pregnancy. The one or rarely two eggs are incubated for three months; the mother burping them every few minutes. When the eggs are hatching, the mother will often gently roll the egg in her mouth to crack it, much as some crocodilians and qurry ornithischians will do for their young.
Even though ambergran eggs are enormous, the hatchlings are still only 10 kilos in size. They are kept well protected by their mother within her jaws in bays and estuaries while their father hunts for both of them. Growth is rapid. The chicks put on hundreds of kilos within months. Their first year may see them nearly 1,200 kilos in weight. Both parents will take the chicks with them out into the open sea after eight months to join the larger flock.
The chicks will remain with their parents for nearly three years; helping with the next hatchling before reaching their adolescent weight of 5,000 kilos and joining their relatives out in the open sea. It will be another 5 years before they consider raising their own chicks.
The latter nomer, ambergran, comes from regurgitated pellets. Ambergrans eat large quantities of deep sea prey, many of while have bones or keratins than cannot be digested. This grain-like oily mush is much like the regurgitations of HE sperm whales and giant diving mosarks in its pungent odor. The musky vomit is being studied with great interest as a possible perfume base.
posted by Raymond @ 10:56 PM
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