ranks of bird society
second author in 2023: the following document was written by another hbf fan in 2019. it will be emphasized later too, but this is a highly speculative document, and an attempt at connecting a few scenes and even dubiously-canon sources. because of this, it’s difficult to link canon sources to each statement, but an attempt will be made!
original author in 2019: bear in mind that uplifted species seem to (quite commonly) have individuals who are not uplifted, even pigeons. this adds a sense of vagueness as to whether a feral representative of a species truly means that species has not been uplifted. so in general if a group of birds has uplifted species in it, ive said that that group as a whole is uplifted. just remember exceptions will always exist. this is a highly speculative document.
1. highest privilege definitely seems to go to columbiformes, meaning pigeons/doves. this includes all of the students, ryuuji, ichijou mino, and most of the hatoful house orphans. they have been shown to have access to at least one exclusive school not available to any other birds (which is also a school that's held in very high regard) and are sometimes even nobility.
because this is very pigeon-centric i don't believe any other birds are in this group, though they may be close. also note that there have been cases of pigeons - namely, wild-type rock doves - being looked down at by other pigeons and even gulls, but that could possibly be more influenced by classism.
2. next are charadriiformes: waders and relatives, such as the gull clerk and gull guard. the gull clerk shows these birds can own successful, "high society" businesses and may even have an elitist attitude. they might not get as many benefits as pigeons, but they do seem to be better off than most other birds. the gull clerk especially seems to have a racist streak.
3. there are then uplifted birds that do not share the same rights as the above groups, but also have not been shown in canon to have experienced the same mistreatment as some others. it is still possible that they DO experience that mistreatment, but i've made a distinction just to be safe. this is the BIGGEST group by far and would include kiwis like pyonpyon, flamingos like domingo santos from the web series, penguins like hoppe, parrots like leone, rabu, and kenzaburou, passerines like azami and albert, and accipitriformes (based on hiyoko fighting a hawk in the manga, and yuuya mentioning being attracted to secretarybirds).
4. the following groups have uplifted members, but also have been shown being cooked in meals and even experimented on with apparently no controversy, so it's possible that they face the most discrimination among birds. in the case of the food, it could be presumed that it's only acceptable to eat individuals who are feral, but since they are so closely related it may very well still be disturbing and uncomfortable to the groups in question. you also can't tell if someone was feral or not if they're already dead and cooked... this group includes galliformes, which are chickens and relatives, including the staff of st pigeonations and tohri as well. pelecaniformes appear to be in this group as well, as pelicans can hold jobs (pelican mailman) but also be experimented on (pellicano). however, the prime minister is a shoebill, which is either a special case on its own or storks are held in higher regard. hitori brings up the prime minister when discussing how far other species have come, suggesting it may be the former and is a case of "look how progressive it is that we have a shoebill for prime minister!"
5. finally, we know some species are extinct. it's likely that a handful of species from every group have disappeared, with the two canon examples being what appears to be some sort of heron and some sort of kingfisher. it is possible that entire groups have gone extinct. in the heron's case, we know that other members of the group live, such as the pelicans and shoebill. the kingfisher is more vague and can't be said for sure.
of course many groups have not been mentioned, and are entirely up to headcanon. any one group may be uplifted or feral (speaking in general terms - again, exceptions) or they may even be extinct. in the following sections i'm going to go over the different layers of bird society, this time discussing which groups are closely related to the canon ones, in case you want to use that as a starting point.
as i said before, it seems like pigeons specifically hold the highest status. however, other members of columbaves may be in rank 2 with gulls. this would include turacos, bustards, cuckoos, mesites, and sandgrouse.
next are the ranking of birds that are considered lower than most others, but have not been shown being mistreated: rank 3. i'll start with relatives of the kiwi, the paleognaths. this would include ostriches, rheas, cassowaries and emus, and tinamous. next, relatives of the flamingo: grebes, rails and cranes. relatives (some more distant) of penguins: albatrosses and petrels, loons, tropicbirds, sunbitterns and kagu. relatives of the hawks and secretarybirds: new world vultures and hoatzin. finally, relatives of parrots and passerines: seriemas and falcons.
as mentioned before, it is possible that ranks 3 and 4 face similar levels of discrimination, and the galliformes have it particularly worse just for being species that are commonly eaten. ducks and their relatives can easily be included in this. but once again i've separated the sections just in case there is an actual distinction. related to these birds are nightjars, oilbirds, potoos, frogmouths, swifts and hummingbirds. and related to the pelican group are ibises, boobies, and cormorants.
this leaves afroaves (including the kingfisher) unaccounted for, making it the grayest area of the bird family tree. it could be that they belong to any of the above groups, are mostly or entirely feral, or even all extinct. for your reference, groups included here are owls, mouse birds, cuckoo rollers, trogons and quetzals, hornbills, kingfishers, and woodpeckers. the majority of birds appear to belong to rank 3 so that would likely be the safest option to assume for these birds as well, assuming they are uplifted and not extinct.
2023 author: there are three birds that i've added post-scriptum, because we didn't know of them at the time. a mallard duck appears in one panel of the manga (at the scene where yuuya is a lifeguard during summer vacation), a puffin operates some kind of booth/kiosk in the land belonging to okosan's parents (manga), and most interestingly: terry mukai, the brewer's blackbird, hatoful's first character who's an actual foreigner.this whole document says, in a very matter-of-fact way, that non-dove bird species are oppressed in the worldbuilding, but i can imagine that that's something that not a lot of other people have talked about. i think one of the key scenes that canonize this indication is, hilariously enough, a hatoful lost media; the story about nanaki and shuu in the guidebook. this short story is not only a source that confirms that phasianids are biologically and socially disadvantaged compared to pigeons, but it's also actually the only place in the source material where nanaki's diagnosis of "narcolepsy" is namedropped.
on a similar note, read more about birdkind's evolution and what characteristics hatoful birds have that are different from ours, here.