Yama Tsukami Ecology

Disclaimer: This is merely a plausible explanation for the monster(s) in this article, and should not be considered canon.

In-Game Information
Retired researcher near the training school: Also known as the 'floating dragon', this elder dragon has never been captured before by man. A gigantic floating hot air balloon wit a large mouth and a number of tentacles. Its mouth is so large, I reckon it would swallow wyverns whole. It's wings have degenerated, and instead, it floats on the gas created during decomposition. It's ancestors floated on water, but it evolved.

Infobook magazine: This dragon is supposedly shaped like a giant mountain floating through the sky. According to some documents, the Yamatsukami has a giant mouth at the front of its body which it uses to swallow whole forests and lakes in one gulp! Plus, the large amount of dirt and rotting flesh decomposing inside its body creates a gas, allowing the Yamatsukami to float through the air without wings. Sometimes when the Yamatsukami breathes out, it may also breathe out some Thunderbugs that it had swallowed. They've mutated inside the Yamatsukami's body, so now they explode if you get to close. Yamatsukami seems to appear mostly near the small side tower just after you pass through the middle of the central tower.

Taxonomy
Scientific Name: Dracovelas Curetes. Yamatsukami is a massive creature technically classified as an Elder Dragon. This is a very loose categorization though, similar to the way Kirin has been labeled an Elder Dragon. Yamatsukami has some reptilian features, yet more closely resembles an aquadic octopi or other large mollusk. Very little is known about the floating beast and it currently has no living genetic relatives.

Habitat Range
Yama Tsukami has only been spotted in a few locations, neither of them decent habitats for a large creature. The creature will occasionally drift by and attack human settlements such as Dondruma, yet the reasons behind this are as of yet unknown. Yama Tsukami is much more commonly spotted at the Ancient Tower, where it appears to rest peacefully at the summit. Since both of these areas are man-made its quite obvious to assume that neither of these regions are the creatures true habitat. One theory suggests that Yama Tsukami has no habitat, and that the creature simply floats high above the range of even flying wyverns such as Rathalos, descending only to feed. Another theory states that the creature will inhabit large forested areas such as the Great Forest, where it will use its long tentacles to anchor itself to the canopy of a very large and ancient tree. Sadly though, Yama Tsukami has not been observed often enough to confirm its true habitat.

Ecological Niche
Yama Tsukami's true ecological niche is unknown. The floating leviathan appears to possess a symbiotic relation with Great Thunderbugs, most likely similar to the relationship between sharks and Remora. The thunderbugs use Yama Tsukami as both a form of protection and a feeding ground, consuming either the scraps left over after the beast feeds or eating the Dragonmoss that grows heavily on the creatures back. Thunderbugs also use Yama Tsukami as a breeding ground, laying their eggs inside the creatures mouth, only to have them swallowed and then later regurgitated as they have matured within the beast's stomach.

Continuing on, it is still unknown exactly what kind of diet Yama Tsukami has. Given the beasts's large molar-like teeth, one could assume it is a herbivore. Yet the creature will actually try to eat hunters using its wind tunnel attack. This has lead some to believe the creature is omnivorous. This theory is plausible, the creature is so docile and rare, that most small creatures may not have an inherit fear of it as they do with more aggressive wyverns. It would not be hard for Yama Tsukami to drift slowly toward a Kelbi or some other small herbivore and quickly inhale it using his wind tunnel. This trick would only work once though, as other prey in the area would quickly scatter, suggesting that the creature gets food elsewhere. Given Yama Tsukami's tendency to have large amounts of Dragonmoss growing on its back, some have suggested that this is the result of plant matter left over from a large feeding that has actually begun growing on the creatures moist skin. Given Yama Tsukami's bulk, it must have to consume a tremendous amount of plant matter to sustain its large girth.

Biological Adaptations
Yama Tsukami's most notable adaption is its ability to float with no obvious method of propulsion. It is theorized that the leviathan possesses a unique organ, similar to a fish's swim bladder that is filled with a lighter-than-air-gas, that helps to keep the creature afloat. Certain bacteria, often found in the digestive systems of living organisms, can produce hydrogen gas, which in most cases is harmlessly absorbed and then dispersed by the creature's bodily functions. It could be possible that Yama Tsukami's digestive process is slow enough (which would make sense given the creature's sluggish nature) and the conditions within his stomach are adequate to support such hydrogen forming bacteria. Another idea is that the Great Thunderbug larvae Yama Tsukami consumes actually digest a portion of the plant matter Yama Tsukami ingests, also producing the hydrogen gas needed to keep the creature afloat. This gas is then diverted into said "Gas Bladder" where it is stored, thus keeping Yama Tsukami floating. The creature can then regulate its altitude quiet literally, by passing gas, expelling excess hydrogen. This also means after a large meal, Yama Tsukami would be heavier, requiring it to remain at a low altitude until enough hydrogen has been produced to get the creature to the desired height. This may explain why the creature can be seen resting at the Ancient Tower It is simply waiting for its meal to digest so it can return to the skies. It is possible that the explosive gas attack is used by releasing the hydrogen gas and then igniting it. The Great Thunderbugs may also explode by igniting the hydrogen gas it had absorbed from the Yama Tsukami by releasing an electrical discharge, just as how the Hindenburg accident occurred.

Yama Tsukami has several other noteworthy adaptations. The creature has four large tentacles that serve as multipurpose appendages. It could use these to snare prey, uproot plants, or anchor itself to landmasses or trees. It also uses them like whips when defending itself, crushing anything that tries to challenge it. Yama Tsukami also has a pair of large whiskers. It uses these to detect various forms of movement, in addition to helping the creature balance itself. These whiskers can be used as pseudo-tentacles if necessary. Yama Tsukami has what appears to be Dragonwood and Dragonmoss growing from its back. The exact cause and reason for this remains unknown, but it serves as a form of insulation at high altitudes. Lastly, Yama Tsukami have incredibly long lifespans, numbering in the thousands of years. The exact cause of their longevity is uncertain, but it is clear Yama Tsukami is as old, or even possibly older than the legendary White Fatalis.

Behavior
Yama Tsukami is an incredibly docile creature. This may stem from its incredibly slow metabolism, or simply the fact that in its lifecycle it never has to be aggressive. The beast uses its large size and ability to fly to get itself out of most situations; however, it can become very hostile if surrounded or cornered. If this happens, the creature is driven into a blind frenzy, and it will try to crush its opponent with its tentacles or even consume it with its wind tunnel. Yama Tsukami do not appear to have any kind of territorial nature, they simply float from one destination to the next, in what appears to be an endless quest for food.