Here is the list of the 338 species (275 lifers) I saw on a VENT tour of Costa Rica, July 7-July 20, 2004. You can also read an account of the trip or go directly to a list of photo links. Species are listed in AOU order, according to the 45th supplement (2004). A hash mark (#) indicates birds previously seen.
I also have photos of a Howler Monkey, Hoffman's Two-toed Sloths, Arenal Volcano, the clouds hanging on the hills, a Torrent Tyrannulet nest, and a waterfall at La Paz Waterfall Garden (#1, #2).
Non-passerines
Ducks, Geese, and Swans: Anatidae
#Black-bellied Whistling-Duck
Muscovy Duck
Chachalacas, Curassows, and Guans: Cracidae
Gray-headed Chachalaca
Crested Guan
Black Guan
Great Curassow
New World Quails: Odontophoridae
Black-breasted Wood-Quail
Pelicans: Pelecanidae
#Brown Pelican
Cormorants: Phalacrocoracidae
Anhinga: Anhingidae
Frigatebirds: Fregatidae
#Magnificent Frigatebird
Bitterns, Herons and Egrets: Ardeidae
Pinnated Bittern
Bare-throated Tiger-Heron (#1, #2)
#Great Blue Heron
#Great Egret
#Snowy Egret
#Little Blue Heron
#Tricolored Heron
#Cattle Egret
#Green Heron
#Yellow-crowned Night-Heron
Boat-billed Heron
Ibises and Spoonbills: Threskiornithidae
#White Ibis
#Roseate Spoonbill
Storks: Ciconiidae
#Wood Stork
New World Vultures: Cathartidae
#Black Vulture
#Turkey Vulture
King Vulture
Osprey, Kites, Hawks, and Eagles: Accipitridae
#Osprey
#Swallow-tailed Kite
Semiplumbeous Hawk
White Hawk
#Gray Hawk
#Common Black-Hawk
Mangrove Black-Hawk
Roadside Hawk
#Short-tailed Hawk
Caracaras and Falcons: Falconidae
Barred Forest-Falcon
#Crested Caracara
Yellow-headed Caracara
Laughing Falcon
Rails, Gallinules, and Coots: Rallidae
White-throated Crake
Gray-necked Wood-Rail
#Purple Gallinule
Sunbittern: Eurypygidae
Plovers: Charadriidae
#Black-bellied Plover
Collared Plover
#Wilson's Plover
#Semipalmated Plover
Jacanas: Jacanidae
Sandpipers: Scolopacidae
#Willet
#Whimbrel
#Ruddy Turnstone
#Sanderling
#Least Sandpiper
Gulls, Terns, and Skimmers: Laridae
#Laughing Gull
#Royal Tern
Elegant Tern
#Sandwich Tern
#Common Tern
Doves and Pigeons: Columbidae
#Rock Pigeon
Pale-vented Pigeon
Red-billed Pigeon
#Band-tailed Pigeon
Ruddy Pigeon
Short-billed Pigeon
#White-winged Dove
#Inca Dove
#Common Ground-Dove
Ruddy Ground-Dove
#White-tipped Dove
Olive-backed Quail-Dove
Chiriqui Quail-Dove
Ruddy Quail-Dove
Cockatoos and Parrots: Psittacidae
Crimson-fronted Parakeet
Olive-throated Parakeet
Scarlet Macaw
Orange-chinned Parakeet
White-crowned Parrot
Red-lored Parrot
Mealy Parrot
Cuckoos and Anis: Cuculidae
Squirrel Cuckoo
Striped Cuckoo
Lesser Ground-Cuckoo
Groove-billed Ani
Barn Owls: Tytonidae
#Barn Owl
Strigidae: Typical Owls
Pacific Screech-Owl
Bare-shanked Screech-Owl
Crested Owl
Spectacled Owl
Mottled Owl
Black-and-white Owl
Striped Owl
Nighthawks and Nightjars: Caprimulgidae
Short-tailed Nighthawk
#Lesser Nighthawk
Common Pauraque
Potoos: Nyctibiidae
Great Potoo
Swifts: Apodidae
Chestnut-collared Swift
White-collared Swift
Gray-rumped Swift
Lesser Swallow-tailed Swift
Hummingbirds: Trochilidae
Green Hermit
Stripe-throated Hermit
Scaly-breasted Hummingbird
Violet Sabrewing
White-necked Jacobin
Brown Violet-ear
Green Violet-ear #1,
#2
Violet-headed Hummingbird
Green Thorntail
Canivet's Emerald
Violet-crowned Woodnymph
Fiery-throated Hummingbird
Blue-throated Goldentail
Blue-chested Hummingbird
Steely-vented Hummingbird
Rufous-tailed Hummingbird
Cinnamon Hummingbird
Stripe-tailed Hummingbird
Coppery-headed Emerald #1,
#2
Bronze-tailed Plumeleteer
White-bellied Mountain-gem
Purple-throated Mountain-gem #1,
#2
Green-crowned Brilliant
#Magnificent Hummingbird
Purple-crowned Fairy
Long-billed Starthroat
Magenta-throated Woodstar
Trogons: Trogonidae
Black-headed Trogon
Violaceous Trogon
Orange-bellied Trogon
Black-throated Trogon
Slaty-tailed Trogon
Lattice-tailed Trogon
Resplendent Quetzal (#1, #2)
Motmots: Momotidae
Blue-crowned Motmot
Rufous Motmot
Broad-billed Motmot
Turquoise-browed Motmot
Kingfishers: Alcedinidae
Ringed Kingfisher
Amazon Kingfisher
#Green Kingfisher
Puffbirds: Bucconidae
White-necked Puffbird
White-whiskered Puffbird
White-fronted Nunbird
Jacamars: Galbulidae
Rufous-tailed Jacamar
Barbets and Toucans:Ramphastidae
Red-headed Barbet
Prong-billed Barbet
Emerald Toucanet (Blue-throated form)
Collared Aracari
Keel-billed Toucan
Chestnut-mandibled Toucan
Woodpeckers: Picidae
Black-cheeked Woodpecker
Hoffmann's Woodpecker
Smoky-brown Woodpecker
Rufous-winged Woodpecker
Cinnamon Woodpecker
Chestnut-colored Woodpecker
Lineated Woodpecker
Pale-billed Woodpecker
Passerines
Ovenbirds: Furnariidae
Red-faced Spinetail
Spotted Barbtail
Ruddy Treerunner
Buff-throated Foliage-gleaner
Streak-breasted Treehunter
Plain Xenops
Woodcreepers: Dendrocolaptidae
Tawny-winged Woodcreeper
Ruddy Woodcreeper
Olivaceous Woodcreeper
Long-tailed Woodcreeper
Wedge-billed Woodcreeper
Northern Barred-Woodcreeper
Cocoa Woodcreeper (sometimes lumped with Buff-throated)
Black-striped Woodcreeper
Spotted Woodcreeper
Streak-headed Woodcreeper
Antbirds: Thamnophilidae
Fasciated Antshrike
Great Antshrike
Black-hooded Antshrike
Russet Antshrike
Dot-winged Antwren
Dusky Antbird
Chestnut-backed Antbird
Antpittas and Ant-thrushes: Formicariidae
Black-faced Antthrush
Tyrant Flycatchers: Tyrannidae
Yellow Tyrannulet
Yellow-bellied Elaenia
Lesser Elaenia
Mountain Elaenia
Torrent Tyrannulet
Ochre-bellied Flycatcher
Slaty-capped Flycatcher
Paltry Tyrannulet
Northern Scrub-Flycatcher
Black-capped Pygmy-Tyrant
Scale-crested Pygmy-Tyrant
Northern Bentbill
Common Tody-Flycatcher
Yellow-margined Flycatcher
Royal Flycatcher
Black-tailed Flycatcher
Tufted Flycatcher
Tropical Pewee
Yellowish Flycatcher
#Black Phoebe
Long-tailed Tyrant
Bright-rumped Attila
Rufous Mourner
#Dusky-capped Flycatcher
Great Kiskadee
Boat-billed Flycatcher
Social Flycatcher
Gray-capped Flycatcher
White-ringed Flycatcher
Streaked Flycatcher
#Sulphur-bellied Flycatcher
Piratic Flycatcher
#Tropical Kingbird
Rufous Piha
Cinnamon Becard
Rose-throated Becard
Masked Tityra
Black-crowned Tityra
Cotingas: Cotingidae
Three-wattled Bellbird
Manakins: Pipridae
White-collared Manakin
Orange-collared Manakin
White-ruffed Manakin
Long-tailed Manakin
Blue-crowned Manakin
Red-capped Manakin
Vireos: Vireonidae
Yellow-green Vireo
Tawny-crowned Greenlet
Lesser Greenlet
Jays and Crows: Corvidae
Brown Jay
Azure-hooded Jay
Swallows and Martins: Hirundinidae
Gray-breasted Martin
#Mangrove Swallow
Blue-and-white Swallow
Southern Rough-winged Swallow
Wrens: Troglodytidae
Band-backed Wren
Rufous-naped Wren
Black-throated Wren
Bay Wren
Riverside Wren
Stripe-breasted Wren
Rufous-breasted Wren
Rufous-and-white Wren
Plain Wren
#House Wren
Ochraceous Wren
White-breasted Wood-Wren
Gray-breasted Wood-Wren
Dippers: Cinclidae
#American Dipper
Old World Warblers, Gnatcatchers, and Gnatwrens: Sylviidae
Tropical Gnatcatcher
Thrushes: Turdidae
Black-faced Solitaire
Black-billed Nightingale-Thrush
Orange-billed Nightingale-Thrush
Slaty-backed Nightingale-Thrush
Ruddy-capped Nightingale-Thrush
Sooty Robin
Mountain Robin
Pale-vented Thrush
Clay-colored Robin
White-throated Robin
Silky-Flycatchers: Ptilogonatidae
Black-and-yellow Silky-flycatcher
Wood Warblers and Wrenthrush: Parulidae
Tropical Parula
#Yellow Warbler (Mangrove form)
Olive-crowned Yellowthroat
Gray-crowned Yellowthroat
Slate-throated Redstart
Collared Redstart
Rufous-capped Warbler
Three-striped Warbler
Buff-rumped Warbler
Wrenthrush
Bananaquit: Coerebidae
#Bananaquit
Tanagers: Thraupidae
Common Bush-Tanager
Sooty-capped Bush-Tanager
Dusky-faced Tanager
Olive Tanager
White-shouldered Tanager
Tawny-crested Tanager
White-lined Tanager
Crimson-collared Tanager
Passerini's Tanager
Cherrie's Tanager
Blue-gray Tanager
Palm Tanager
Plain-colored Tanager
Emerald Tanager
Silver-throated Tanager
Golden-hooded Tanager
Spangle-cheeked Tanager
Scarlet-thighed Dacnis
Blue Dacnis
Green Honeycreeper
Shining Honeycreeper
Red-legged Honeycreeper
Seedeaters and Sparrows: Emberizidae
Blue-black Grassquit
Variable Seedeater
White-collared Seedeater
Thick-billed Seed-Finch
#Yellow-faced Grassquit
Peg-billed Finch
Slaty Flowerpiercer
Sooty-faced Finch
Yellow-thighed Finch
Large-footed Finch
White-naped Brush-Finch
Orange-billed Sparrow
Black-striped Sparrow
White-eared Ground-Sparrow
Stripe-headed Sparrow
Rufous-collared Sparrow
Cardinals, Grosbeaks, and Saltators: Cardinalidae
Grayish Saltator
Buff-throated Saltator
Black-headed Saltator
Black-faced Grosbeak
#Blue Grosbeak
Blackbirds, Orioles, and Oropendolas: Icteridae
#Red-winged Blackbird
#Eastern Meadowlark
Melodious Blackbird
#Great-tailed Grackle
#Bronzed Cowbird
Giant Cowbird
Black-cowled Oriole
Yellow-billed Cacique
Scarlet-rumped Cacique
Chestnut-headed Oropendola
Montezuma Oropendola
Finches and Euphonias: Fringillidae
Scrub Euphonia
Yellow-crowned Euphonia
Thick-billed Euphonia
Yellow-throated Euphonia
Elegant Euphonia
Olive-backed Euphonia
Tawny-capped Euphonia
Golden-browed Chlorophonia
Old World Sparrows: Passeridae
#House Sparrow