Unfezant has the highest base stat total of all the Pokemon you showed.
Noctowl has the highest HP.
Staraptor has the highest Attack, although Swellow has Guts.
Unfezant has the highest Defense, although Staraptor has Intimidate.
Noctowl has the highest Special Attack.
Noctowl has the highest Special Defense.
Swellow has the highest Speed.
However, Unfezant is definately not the strongest. Noctowl, Swellow, and Staraptor are better than it. Maybe Pidgeot, but Unfezant's support function helps it be better than Pidgeot I think.
Staraptor is the best. WHile the others have stats all over the place and never in one good area, Staraptor knows what it is doing. It's Sweeping with 120 base Attack and 100 base Speed. And with Intimidate making it weasy for it to switch in on weaker physical attacks and take priority better, it does the job all that much better. It can also use its DW ability of Reckless to hit everyting even harder. Because it has powerful STAB recoil moves with Brave Bird and Double-Edge. Also something that makes it best of the Pokemon you listed is the fact that it learns Close COmbat, allowing it to use a base 120 power attack against the Steel and Rock types that would usually wall the birdies.