Owls and snakes declare the owls' superiority over birds because owls regurgitate pellets instead of producing regular droppings, and theydo! And the fact that plenty of other birds, such as crows, also regurgitate pellets is never even touched upon.
They certainly wouldn't be the first race or group of people to think — literally in this case — their sprink don't stink.
Ahem. "Although owls did digest the soft parts of their food in a manner similar to other birds, and indeed passed it in a liquid form, for some reason they were never associated with these lesser digestive processes."
While that explains the first bit, it doesn't explain the second. And that's not even the only example of Dan Browned. The book also goes on to claim that burrowing owls dig all their own burrows (not true; most don't); and that no owls are ever up during the day (some, such as the short-eared owl and great gray owl, are, on occasion).
Heck, snowy owls spend a fair amount of time up during the day in spring and summer, due to their natural range being fairly far north - when the sun is up for longer amounts of time, you really don't have much choice. (Though this does get some mention with the owls in the Northern Kingdoms.)
Not to mention that seagulls, the butt of owl jokes on the subject, also regurgitate pellets.
These books also continuously have the owls taking note of various scents, both strong and faint. Owls are one of the primary predators of skunks. Think about that for a moment. In truth, most birds (except for kiwis, members of the tubenose family, and some vultures) have almost no sense of smell. Evidently this was pointed out to the author at some point, as a few characters starting with the eighth book Hand Wave this with what basically boils down to "in this universe an owl's sense of smell is only poor compared to that of wolves and some other animals."
Probably the most glaring example of this is when a skunk attempts to spray Coryn partway through book eight. He's said to be safe from the smell because he's flying too high to be hit, when in reality it shouldn't bother him even if it did hit him.
The idea that crows are idiots. They're not. In fact the corvids (crows/ravens/etc.) are among the smartest birds - usually considered the smartest. The magpie trader and ravens, however, are portrayed as somewhat smarter than their crow cousins, though nowhere near as smart as the owls. In real life, it's the other way around: owls range in intelligence from roughly average as birds go to fairly smart, but typically nowhere near the level of corvids.
The owls, as essentially narrators of the series, are speciesist and thus unreliable?
This could be it, except that the crows' behavior in the books seems to support the "idiot" stance. Maybe the author just doesn't like crows...
Actually, it's more that the two sets don't really like each other. I once witnessed a horned owl being harassed by a small murder.
In early books, falling into the ocean is treated as a real danger because the owls' feathers would become saturated and they would not be able to lift off again. Then we come around to the books entailing the story of Hoole, and suddenly we've got owls willingly diving into the ocean to catch fish, and the sea is now only dangerous to hagsfiends. Never mind the fact that even fishing owls really only grab for fish from the surface, rather than diving.
Kind of a mix of Fridge Logic and It Just Bugs Me!. Weapons like battle claws and swords of ice were somehow invented long, long before fighting with burning branches. Even if we decide to roll with the idea, one would think that it wouldn't take a few hundred years for some owl to figure out that a lighted branch could be useful in battle, but apparently it simply didn't happen before the Band came along.
Fighting with fire did exist, it just wasn't popular until the Band made it into a strategy. Plus, think about it- owls usually live in or near combustible objects. How many innocents could one kill if they decided to fight with fire on unknown territory? Of course, hagsfiends wouldn't be concerned about that, but it's stated that hagsfiends aren't the sharpest tool in the shed.
Additionally, the Northern Kingdoms, which was the centre of power in Hoole's time and still is a central location for many of Owl Kingdoms in Soren-Coryn time lack trees and tinder to make fire-fighting an effective strategy. Heck, battleclaws and forging were invented on the only island with trees on it, so hence, ice weapons make the most sense. The Southern Kingdoms, where the Band invented fighting with fire as a strategy actually had the forest growth to allow such a thing.
Not entirely sure if this is the right area, but a brain large enough for complex thought should also be too heavy for flight except for exceptionally large birds. Now throw on the numerous items they claim to carry and it leads one to question how they fly at all.
Could be considered an acceptable break from reality. Any story featuring nonhuman animals behaving in ways that could be seen as humanlike requires this sort of thing - really, complex thought and brain size take a back seat to all the rest of the things going on in this series. note Also keep in mind that brain size and mental capacity don't correlate nearly as cleanly as many people think. Rats are capable of rapid, complex problem-solving on the same level (and in some cases, arguably on a higher level) as dogs, for example, while giraffes have brains roughly equal in size to humans while not showing nearly the same level of complex thought. Not to say that brain size plays no role in determining intelligence, as it's definitely a factor, it's just not a very clean cut one in some cases.