This just contains some thoughts and notes on creatures introduced at Disney's Pandora: The World of Avatar, through the Flight of Passage ride.
The first we see is the smaller (though probably direhorse sized) ilu, jumping and swimming together like dolphins. I'll re-post the text from the "Pandoran Field Guide" (at Disney) here:
"The ilu is a large plesiosaur-like sea creature that is the direhorse of the Pandoran ocean. With multiple fins/flippers and a long streamlined shape, this aquatic pack animal serves the reef Na'vi clans like direhorses serve the Na'vi of the forests, jungles and plains."
By studying the Flight of Passage ride carefully, it can be seen they swim in the up-down motion of dolphins and porpoise (jump) out of the water as they go. It is not known if ilu need to breathe air, and it is not specified, but one can also be seen breaching (it looks like a belly flop) like orcas do and another a flip, breaching the water upside down and twisting sideways before disappearing under a massive wave. They are shown both in shallow, near-shore waters and deeper waters.
The ilu, shown in a pack of over a dozen individuals, has colorful patterns and markings on top (including blue, yellow, purple, orange, green and white) while their undersides are a smooth, white belly. Like the ikran, the patterns of the ilu extend on the bottom side along the tips of its four back "wing flippers". The head and queue tentacles are set up very similarly to an ikran, from what can be seen, with the two queue sweeping backward from the side back of the skull. A long neck attaches to a rounded, pear-shaped body. The front two flippers are small and seem to be mostly white on bottom like the belly. The front set of small flippers and the large 'wing flippers' behind it sit horizontally in the middle of the body and are moved up and down, while the last large pair of 'wing flippers' are positioned on the underside of the peduncle, also horizontally positioned. These last two seem to serve the function of a tail, as the middle, very back of the ilu has an inward horizontal "c" shape (when viewed from below) that evolve into the tail flippers; above it, the body seems pointed--hence the second, vertical "c" shape arising on the drawing on the ilu. It is very likely the last, underside tail flippers are used for balance and steering, while the middle, upper wing-flippers are used for thrust, as are the very front, small flippers.
Lastly, after many viewings of the Flight of Passage ride, I came to note that the ilu that jumps near the reef barrier is also jumping upside down, so it's important to keep that in mind while watching. Its white underside with few markings is clearly visible.
Curiously, they are shown to live in close proximity to the nalutsa, an animal so big it makes the ikran look like a tasty treat and not a whole meal.
From the Field Guide: "Nalutsa: A cousin of the more elusive and fierce akula, this six-gilled ocean behemoth can be seen leaping out of the near-waters. Birthing and parenting behaviors are not dissimilar to those of orca whales on Earth."
It first makes its appearance breaching out of the water in a similar manner to a humpback whale, with the twist and all, and it even has flippers that look like a humpback's. While the first one seemed to be breaching for no apparent reason, the second had a clear goal, and it was to snatch something out of the sky. A few more rides showed it, too, was trying to snatch something out of the sky, but failed horribly. I was trying to figure out WHAT the nalutsa was snapping at, because whatever it was was so tiny in comparison--only to realize it was trying to eat an ikran flying ahead of us! While both nalutsa failed in this task (probably because it would be distressing on a Disney ride to witness a successful kill), I don't see them failing in the upcoming Avatar movie. For those who do not know, James Cameron has already said it will take place in and around Pandora's oceans.
This brings up a curious thought, because I need to stress the Field Guide text above specifies the nalutsa has GILLS, which means it doesn't breathe air, so in this it is like a shark. What is it about ikran that the nalutsa would spend all that energy trying to devour it, when similarly-sized ilu were jumping all around in the water? I must draw a parallel to a humpback again here, since the nalutsa were inspired by them. Humpbacks, being baleen whales, use a lot of energy to feed, and need to get the maximum reward for their efforts. They have been shown to avoid complete lunges at clouds of krill if the krill cloud is not dense enough; that is, there aren't enough of them that are worth the effort for a complete lunge. The humpback will then purposely avoid charging into them. So what is the nalutsa up to? It doesn't need to breathe air and there does not seem to be a reason for it not to eat the ilu. What's the logic here?
The only thing I can think of is the comparison to orcas. While the field guide only mentions parenting behaviors, there are three nalutsa together in the first appearance, and at the end, two of them, with a third swimming up in the water from the left side (you really have to be paying attention to see it). It can be safely assumed they live in small groups, not dissimilar to orcas or humpbacks. But I want to mention orcas because they have very picky eating habits: The Southern Resident Killer Whales of Puget Sound are suffering in their population because they only have one food source--Pacific salmon, mostly chinook salmon, and because the salmon populations are suffering (especially Chinook), so are they. Conversely, the other orcas who call Puget Sound home, the Transients, are doing very well and are not experiencing all of the problems related to food shortage that the Residents are experiencing. Transients eat mammals, including porpoises, whales and pinnipeds (like seals and sea lions). Perhaps it can be surmised that due to culture and what has been passed down over generations, the nalutsa, at least these ones, simply prefer to eat ikran that live along the coast, and leave the ilu alone.
Like the ilu and whales on earth, I was under the impression the nalutsa swims in an up and down motion. However, after a second trip to Pandora I realized that you can indeed see it moving in a side to side motion--if you happen to be on the right side of the ride and look far left BEFORE the ikran lands on the final perch, you can see the nalutsa coming up who is doing to do the large breach at the end. It does look to be doing a large, long side-to-side motion.
It is a dark blue, not bright, on top and has a distinct white underside, including on its flippers. While both sets of front flippers (big front ones, smaller rear ones) look like a humpback's, and they twist as they jump, that is where the similarities disappear. The nalutsa is also clearly reminiscent of a great white shark in its coloration pattern and the fact it was rows of triangular-shaped teeth in a shark-like mouth. Two flaps of skin hang from the upper jaw on each side of this mouth, and right behind it are the gills. Like the direhorse, the nalutsa seems to sport plates on its back, but these distinctly do not sit completely flat, at least in the official line drawing, and the hint of them can be seen out of the close nalutsa that breaches near the rider during Flight of Passage. The Nalutsa's tail is two pronged and is proportioned like a great white shark's. It is a bit confusing, at least to me, how the nalutsa swims with an up-down motion if it's tail is vertical. (The up-down motion is evidenced by the one swimming under the big wave). The nalutsa swimming at the very end of the ride, under the water, seems to be gliding and so I have not been able to 100% verify if the nalutsa does indeed swim in an up-down motion, or side-to-side.
Very curiously, I also noted on my last trip a mural in Windtrader's, on the ceiling, that shows the nalutsa and the ilu. The painting has the nalutsa with undulating 'flippers' (I'm not sure what they're actually called) on the back half of it along its sides. While I am inclined to take an artistic representation of the nalutsa at Pandora as accurate, I DID note that the large creature has a pronged tail (two horizontal flaps and one top vertical one) before the tail tapers off into a long narrow end in Flight of Passage; the mural painting does not seem to indicate this on the tail.
The nalutsa though, looks very much like a dakosaurus or plesiosaurus: i.huffpost.com/gen/799933/imag…
I also highly advise watching this, for the first and forth creatures were clearly inspiration for the nalutsa:
That concludes all of my thoughts and observations on these two new creatures. I can't wait until we get to glimpse them again... maybe we will get them in the upcoming Avatar comic, if we're lucky, or even in the book that's supposed to come out (No news on this book for years, though, so no getting hopes up too much!).