Laguna Atascosa National Wildlife Refuge (WH)

Location: South coast of Texas, near Brownsville

Why Special: Most of the southern Texan habitats, complete with their Mexican specialties, are present in this National Wildlife Refuge, with grassland and coastal habitats present that are not found in any of the other famous Lower Rio Grande birding locations. Within the refuge boundaries it is possible to see a wide assortment of birds, ranging from northern and prairie migrant waterfowl and waders, through southeastern waders like Rosette Spoonbill and Reddish Egret, to Mexican “exotics” like Green Jay and Plain Chachalaca. This sort of diversity cannot be matched anywhere else in southern Texas in a single day of birding at one location.
Habitat: thorn scrub, grassland, coastal beach
When To Go: winter; mornings and afternoons
Birds to Look For: Green Jay, Crested Caracara, White-tailed Hawk, waders, waterfowl, Plain Chachalaca

Bentson-Rio Grande Valley State Park (WH) (AW)

Location: Lower Rio Grande River, near McAllen, Texas
Why Special: Accessible to the public not just during the day, but also at night when birds like Common Pauraque can easily be seen by walking the roads in the park. (WH) It’s one of those legendary birding places that has earned its reputation. The park no longer allows trailer or RV camping but numerous trailer and RV campgrounds are available nearby. Tent camping is still allowed. A World Birding Center is located near the entrance to the park and WBC staff can help visitors enjoy the nearby mind-blowing birding. I remember arriving right before dusk near the tree a pair of Elf Owls were using. There were dozens of birders already there, with scopes and cameras ready. When the tiny owl popped up into the cavity, in full view, there was a collective, “Ooohh.” Added bonus: saw my first free-ranging tarantula here (headed straight for the women’s bathrooms!) (AW) Habitat: Riparian forest, thorn scrub
When To Go: Winter and early spring
Birds to Look For: Elf Owl, Hook-billed Kite, Common Pauraque, Plain Chachalaca, Neotropical Cormorant, Harris’ Hawk, Tropical Parula, Common Pauraque

Chapinga and Salineno

Location: Texas, just south of Falcon Lake
Why Special: These two locations are ideal for birders looking for great birds but are unable to move around as well as when they were young. Look for the "bird lady" at Chapinga and the beautiful but natural birding locations right on the Rio Grande River. 

Just south of Chapinga is a small trailer parker where the Dewinds welcome birders each winter.  The area is now owned by the Valley Land Fund.
Why Special: The great mix of both common and rare birds, please the laid back approach.
When to go: November to March is the most productive.
Birds to Look For: Here's a sample.

Big Bend NP (JG)

Location: Texas
Why Special: The variety of habitats makes this a great place to bird and hike.
Habitat: River, desert, coniferous and deciduous forest, desert scrub
When To Go: Spring and fall (when the agaves are blooming)
Birds to Look For: Quail, Colima Warbler, Painted Redstart, Gray Vireo, Zone-tailed Hawk, western sparrows, Lucifer and Blue-throated hummingbirds.

High Island (JG)

Location: Texas
Why Special: If you time it right, I don't know any place that will give you better/closer looks at warblers.
Habitat: Hammock forest, fresh and salt marsh and beach
When To Go: Spring migration immediately after a storm front has gone through the gulf.

Birds to Look For: Spring migrants, warblers including Swainson's, grosbeaks, tanagers, orioles, cuckoos, etc.

Santa Ana NWR (JG)

Location: Texas
Why Special:
Never know what you'll see here, always seems to have a rarity or two.
Habitat: Scrub forest, grassland, ponds
When To Go:
Winter and late summer, though I'd go anytime
Birds to Look For: Altimira Oriole, Hook-billed Kite, Ringed Kingfisher, and who knows?

South Padre Island Convention Center (WH)

Location: South Texas coast, northeast of Brownsville on South Padre Island
Why Special: Rails, particularly the elusive Yellow Rail and Black Rail, are much sought after by birders. At this location it is possible to see every single species of U.S. rail, particularly in winter, using a couple of short boardwalks built into the salt marshes that lie between South Padre Island and mainland Texas. Sora and Clapper Rail are particularly visible in winter…even Clapper Rails eating Sora can be seen at the Convention Center. Also Reddish Egret and Roseate Spoonbill.
Habitat: Coastal saltmarsh
When To Go: Winter, best time determined by the tides (higher is better for flushing the rails out of the salt marsh).
Birds to Look For: Rails, herons, Roseate Spoonbill

Quivira NWR/Cheyenne Bottoms (MP)

Location: Great Bend, KS
Why Special: Wetland habitat surrounded by grasslands and agricultural fields attracts an incredible diversity of birds.
Habitat: Salt marsh, sand dunes, prairie grasses, tree lines.
When To Go: Spring
Birds to Look For: Migrant passerines; waterfowl, shorebirds and waders including Snowy Plover, phalaropes, and Black Rail

Lake Fayetteville (MP)

Location: Fayetteville, AR
Why Special: Nice mix of bird species all year round, easy access and walks.
Habitat: Open water, old fields, bottomland and upland forests
When To Go: Year round
Birds to Look For: American Woodcock, warblers, vireos, thrushes, and other songbirds in spring, Bald Eagle, Bufflehead, Ruddy Ducks and others in winter, sparrows in fall and winter

Centerton Fish Hatchery (MP)

Location: Centerton, AR
Why Special: Easy access, great looks at expected shorebirds and the occasional rarity, western vagrants
Habitat: Man-made ponds and mudflats surrounded by agricultural fields, stands of deciduous trees, shrubby areas.
When To Go: Fall, Winter, Spring
Birds to Look For: Shorebirds and raptors in migration, waterfowl in winter, warblers and vireos in spring, sparrows in fall/winter

Willow Slough State Fish and Wildlife Area (JG)

Location: Indiana
Why Special: A great variety of birds (this is where I started birdwatching)
Habitat: Marsh, swamp, coniferous and deciduous forest, grassland
When To Go: Early spring to early summer
Birds to Look For: ducks, rails, eastern migrants, western vagrants.

Jasper-Pulaski State Fish and Wildlife Area (JG)

Location: Indiana
Why Special: Sandhill Cranes by the thousands
Habitat: Forest, grassland, agricultural fields and ponds
When To Go: Mid-October to November
Birds to Look For: Sandhill Cranes

Hawk Ridge (JE)

Location: Duluth, Minnesota
Why Special: Incredible hawk migration during most of fall.
Habitat: Mixed decid/coniferous woods around the ridge.
When To Go: Go in late September, October or early November.
Birds to Look For: Hawk Ridge is at the south end of the North Shore of Lake Superior, which funnels migrants down the shore in fall. Very large (100,000+) movements of Broad-winged Hawks have occurred here, as well as large movements of Sharp-shinned and Cooper's hawks. This is a reliable spot late in the season for Northern Goshawk and Golden Eagle. Passerine migration can be quite good, with large numbers of birds (sometimes including crossbills and Evening Grosbeak) moving through. Early in fall, large numbers of Common Nighthawks pass by as well.

Minnesota Valley National Wildlife Refuge (JE)

Location: Bloomington, Minnesota (in the Saint Paul/Minneapolis area)
Why Special: It's long and it's urban, and is therefore easily accessible. It protects habitat both for resident breeding species such as Prothontary Warbler and Dickcissel, and for a massive number of migrants of all types, from ducks to wood-warblers.
Habitat: Covers a wide range of habitats, ranging from backwater marshes of the Minnesota River to upland prairies and remnant and restored oak savannah.
When To Go: Go almost any time - there are gulls in the winter at Black Dog Lake, warbler fallouts in spring and fall, and breeding marshbirds in summer.
Birds to Look For: Nesting Prothonotary Warbler, Virginia Rail, Least Bittern, Scarlet Tanager, Dickcissel, Bald Eagle, Peregrine Falcon. Migrant: Over 20 species of wood-warblers, ducks galore. Winter: Gulls of several species, including Minnesota rarities like Iceland Gull, Thayer's Gull, Great Black-backed Gull, Glaucous Gull. Large concentrations of wintering waterfowl, including Common Merganser, Snow Geese, and goldeneye.

Park Point (Minnesota Point) (JE)

Location: Duluth, Saint Louis County, Minnesota
Why Special: A great migrant trap in fall and spring, both for birds on the lake (Lake Superior), and migrating passerines moving up the shore.
Habitat: Open beach, lake, park, parking lot, and a strip of woods down the middle.
When To Go: The point is best during migration, and is worth checking both early in spring and late in fall.
Birds to Look For: This is one of the best places in Minnesota to find Red-throated Loon. Shorebirds may turn up on the beach, and on the bay side of the point, and scotors (tough to find in MN) may be found in either the bay on the south side or the lake side. Foggy mornings in spring sometimes cause a buildup of migrating passerines on the point, waiting for better weather to cross the lake, and some mornings have 20+ warblers (including Mourning, Golden-winged, and Connecticut), and many other passerine birds.

McGregor Marsh (JE)

Location: McGregor, Aitkin Co, Minnesota
Why Special: A western oasis in eastern Minnesota, with Yellow Rails and Nelson's Sharp-tailed Sparrows
Habitat: Sedge marsh
When To Go: summer, when both of these birds are breeding and calling
Birds to Look For: Yellow Rail is very reliable here, as is Nelson's Sharp-tailed Sparrow. For the former, you have to much further north to find them again, and the latter, north and far west.