Casts Raise Thread
Bird companion can be made pretty good, if you invest in it:
1: At 4th level, use the option to take +2 Dex & Con instead of the listed upgrade. Sticking with that means weapon finesse stays good and you just get more AC / Initiative & reflex for your evasion. Net attack roll goes up instead of down ;-)
ALSO...
2: Get it an Agile Amulet of Mighty Fists (4k gp), it will now add its Dex to damage instead of Strength (should be a +5 dex mod or more by 4th, if you follow advice #1 above.)
3: Consider being human, and taking the "Eye for Talent" alternate racial ability --gives up your bonus feat for +2 Dex to your bird, and you get a bonus on Sense Motive or something. That's another +1 to hit / ac / reflex / initiative / dmg (with Agile).
OR it could be +2 Int to start with an Int of 4... that's 6 more Tricks, and you can have your bird take -any- feat from level 1... How about juicy ones like Death From Above? Additional Traits? Flanking Foil? etc...
OR, ALTERNATIVELY: Be an Aasimar which allows you to take the Celestial Servant feat --gives your bird the simple Celestial Creature template: Darkvision, scaling damage reduction & elemental resistances, and Smite Evil 1/day... lol!!
4: If you're open to multiclassing, you could consider:
Hunter dip 2 levels: May seem redundant but a free Precise Shot feat for you (if ranged) or Outflank for both you and Bird (if melee) is nice, and so is ability to give your bird +2 all day to any physical stay, and hey also you get Resist Energy as a 1st level spell --bonus! Also, if you do this you can use some of your animal's tricks to teach it special Skirmisher Ranger abilities... like Entangling Strike, Tripping Strike, etc... That's pretty boss.
OR SIMILARLY: Sacred Huntmaster archtype for Inquisitor would give you Hunter style Animal Companion option for thos Skirmisher tricks (but not the Animal Focus buff).
ALSO If you push Hunter to 3rd level you get more options like either Teamwork feats with Bird or the Divine Hunter archtype: So humans can now make bird celestial anyway (and still get their +2 bird stat from Eye for Talent), OR, Aasimar can use Celestial Servant to make bird Celestial AND ALSO use Divine Hunter 3rd to make Bird Fiendish at same time... crazy but legal RAW. So bird now has scaling resist to all 4 elements and his DR is both Good & Evil (aka +5 weapon or Smite is only way past his DR.)
OTHER IDEA: Another weird dip is Huntmaster Cavalier. At 3rd level their Bird gets to make free Dirty Trick checks on every attack, from a limited set: Deafened or Dazzled, but, if target already Dazzled (say from your Death from Above partial charge in the Surprise round) then bird can do Blinded.
...That's strong. Especially if they also have Skirmisher tricks like Entangle and Trip. That means at 4th level, in round 1 or 2 of combat the bird has made 1 target Blind, Deaf, Dazzled, Tripped and Entangled off of 3 or 4 attacks. And done damage 1d3/4 +5 or +6 like 3 or 4 times. That makes the summoner's Eidolon look like a chode, and the other druid's boring Big Cat look like a Big Pussy. lol...
Feats & Traits:
Trait: Blackthorn Rancher (regional). Take this to give your bird +3 Hp at 1st level. Gives you bonus to handle Animal as well.
Trait: Deadeye Bowman. Take this (and worship Erastil) to ignore soft cover from your Bird or your party meat shield... err... fighter, so you can shoot lots of Abundant Ammo Trip Arrows, Tangleshot Arrows and maybe even Pheromone Arrows (if anyone in your party has Scent) from a safe distance, without the Pesky -4 to hit. Works best paired with Precise Shot from Hunter 2nd.
Feat: Andoran Falconry (aka Master of Falcons). Requires Animal Affinity (sigh) but gives choice of bonuses to Bird. Best: +2 morale to Will saves if you took Totem Guide (since Bird lost Devotion in that case), or, +1 morale to attack rolls... IF you then give Bird Additional Traits feat and give it trait: Adopted: Half Orc (menacing or whatever it's called racial trait that adds +1 to damage whenever you have morale bonus for attacking... which is 100% of the time for your bird ;-)
Spirits Gift (non PFS only): Best feat for anyone with an animal companion. Probably use the DR 5 option most days at low level, though the 24 hours Blur is great too if you have Bird invest in stealth (effectively Hide in Plain Sight... yes, it's true, with 1 feat you take your Bird becomes a better Shadow dancer than the damned prestige class.)
Hunmaster: Requires being Human, Half-elf, half-orc or Aasimar (w/ Scion of Humanity alt trait): +1 effective level for your Bird companion, which unlike Boon companion or similar feats THIS CAN raise level past PC a actual level.
Evolved Companion (non-PFS again): this breaks the game. Avoid it unless you need revenge on a trash talking melee party member or whatever... in which case, reach on you bird is nice, as are all the other broken summoner options.
Totem Beast: Scaling +2/4/6 to a stat of your choice for your Bird. Sweet!
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There's more you can do than this, but this should get you started.
Enjoy.