Wingull in depth
From 鴎 to キャモメ
The Japanese name is almost untouched as a noun: キャモメ, Camome, comes from 鴎 (kamome), which means seagull in Japanese. English reaches the same place by another route, combining wing and gull. Two languages and no metaphor involved.
The design follows that literalness. White body, blue markings near the ends of the wings, a long, pointed beak for fishing, webbed feet and a tail split into three. There is no layer of fantasy over the real animal, and in the third generation that worked well: Hoenn has more sea than land, and whatever flew over the boat had to look like harbour wildlife.
The behaviour is copied from nature too. Stealing food and shiny objects to hide them in several places is standard seagull repertoire, and following the flocks to locate schools of fish is an old, real fishing technique, not a writer's embellishment.
A seagull with a name of its own
The appearance most people remember is not a catchable specimen, but one with a name: Peeko, Mr. Briney's Wingull, an NPC in Ruby, Sapphire, Emerald and their 2014 remakes. The fact that a species with 270 base stat points has a speaking role in the story of an entire region says quite a lot about how little the numbers matter outside battle.
The only significant change it has undergone since its debut is a matter of bookkeeping. In Generations III and IV, defeating it awarded 64 base experience points; since the fifth generation, it has awarded 54. Its hidden ability, Rain Dish, was not available from the beginning either: it arrived in Generation VII. Neither its type, its stats nor its evolution level have been touched in more than twenty years.
The countdown to 25
As a playthrough teammate, it is best treated for what it is: a stage. It gives 1 Speed effort point when defeated, which is useful if the aim is to train something else, and it learns Supersonic at level 10, which in the hands of a patient player turns any difficult catch into a confused opponent that hits itself. Agility, at 26, is no longer needed by anything with 85 Speed.
Compared with Taillow, the other bird found early in Hoenn, it loses out in power and gains in coverage: one hits things and the other gets you places. Against Ducklett, Unova's marine equivalent, the difference is in the distribution—the seagull puts everything into Speed, while the duck spreads a little more into staying power.
The interesting part comes immediately afterwards. Wingull is one of the few cases where evolution does not improve the creature so much as turn it into something else: it loses its light silhouette, gains bulk and changes jobs. The forty-five levels of moves listed for it, up to Hurricane, are a plan that in practice is never carried out, because nobody leaves a creature with 40 HP unevolved for twenty levels just to see the bottom of the list.