Wintering species are well in place by January. The northern third of the state hosts visitors such as Northern Shrike, Rough-legged Hawk and American Tree Sparrow. All three species of Rosy Finches are found at feeders in Taos and on Sandia Crest near Albuquerque. Several species of loons frequent the larger lakes around the state. Thousands of Western Grebes find Elephant Butte Lake to their liking as do a surprising assortment of gulls. The Rio Grande Valley from Socorro south is mild enough to attract a superb mix of waterfowl, cranes, raptors and sparrows. By the end of February, the lengthening days prompt the Sandhill Cranes to embark north and the Crissal Thrashers to begin singing in our southern desert.
As we head into March, far north breeders such as Bald Eagle and Common Goldeneye have departed the state. Warmer days in mid-month herald the arrival of the year's first Turkey Vultures and Swainson's Hawks. The hardier swallows, Tree and Rough-winged, push into the state by then as well. Many resident owls, such as Western Screech, Spotted and Boreal, are in courting mode by this time, even with heavy snows still blanketing most of the mountain ranges. April is ushered in with the astounding calls of the Lesser Prairie Chicken as the birds begin to gather on leks in the sandhill country east of Roswell. The winds of mid-April signal a real changing of the guard with almost all wintering species gone and shorebirds, ibis, some passerines and even hummingbirds surging north. Cave Swallows return to to their northern outpost at Carlsbad Caverns as well. By the end of the month, many neotropic migrants, such as Painted Redstart and Elf Owl, are on territory in the southwest mountains of the state.
The beginning of May marks the songbird migration in earnest. Flycatchers, warblers, vireos and more are streaming north, primarily along the Rio Grande and Pecos River corridors. Some are bound for the mountains of northern New Mexico while others will ultimately claim a spot in the boreal forest of Northern Canada. The shorebird migration is strong at the beginning of the month but dwindles rapidly except for the rear guard of White rumped Sandpipers, who are still passing through the second week of June. While breeding for some species is finished in the souuthern deserts by early June, it is just getting into full swing in the northern mountains. At this time we will hear the stunning chorus of the Hermit Thrush throughout the mountainous regions while its rarer cousins, Veery and Swainson's Thrush, are confined to a few limited outposts in the northern Sangre de Cristos. The highest forests, up to 12,000 feet, will hear the basso profundo of the bird world, the Blue Grouse, hooting well into June. Other high altitude avian delights include Gray Jay, Clark's Nutcracker and, in wet years, roving flocks of Evening Grosbeaks and Red Crossbills. For hardier birders, June is the time to hike above treeline in search of White-tailed Ptarmigan (before the lightning season commences in July!).
Even while late breeders, like Cordilleran Flycatcher and Yellow-billed Cuckoo, are still feeding young, the southbound migration has begun. Early July finds the first wave of shorebirds such as Solitary and Stilt Sandpiper, already in our middle latitudes and by the second week Rufous and Calliope Hummingbirds are well represented statewide. Fall songbird migration lacks the urgency of spring and is far more protracted. Most mountain species have drained into the lowlands by mid-August. Certain species that visit only in fall, such as Hermit Warbler in the southwest mountains and Upland Sandpiper in the eastern plains, have largely departed the state by the end of August. Shorebird numbers peak in mid-August, particularly at major stopovers such as Bitter Lake National Wildlife Refuge where the birds, newly arrived from the arctic tundra, seem unfazed by the 100 degree heat. August is also the month when southern herons wander north up the Pecos and Rio Grande into New Mexico. Reddish Egret and Tricolored Heron are almost annual and infrequent sightings of Roseate Spoonbill add an exotic element to our high desert birding landscape.
The peak passage for songbirds is witnessed in the first half of September and hummingbird numbers have dropped way off by mid-month. At the same time, waterfowl numbers are on the rise. As with August, September provides us with a chance to view several species rarely seen in spring such as Townsends's Warbler, Sabine's Gull and Red-necked Phalarope. By early October, the first major cold fronts of the season have pushed most of the tropic-bound songbirds out of the state. The first snows on the northern mountains by mid month confirm that the kingbirds and swallows we grew accustomed to are now memories until next spring. As the winds turn to the northwest, the bugling of Sandhill Cranes can be heard over the Rio Grande Valley.
As the cold blasts of November become more frequent, we tend to think migration is over yet there is still a great deal of movement. Bald Eagles are taking up winter residence at major lakes and rivers statewide. Snow and Ross' Geese descend enmasse from Canada furing the first week of the month. Waterfowl and sparrow numbers increase steadily. November is usually the only month we see scoters in the state, most commonly first year birds. Chesnut-collared and McCown's Longspurs continue to pass through, with some settling in the southern part of the state to overwinter. In December, migration is winding down although Tundra Swans and various gulls still filter through during the first half of the month. Many species, such as Townsend's Solitaire and American Pipit, have now completed their "vertical migration", simply dropping from treeline breeding grounds into protected foothills and valleys.