White-throated Swift (Aeronautes saxatalis)   NMPIF level: Species Conservation Concern, Level 2 (SC2)    NMPIF assessment score: 15 NM stewardship responsibility: Low National PIF status: Watch List New Mexico BCRs: 16, 18, 34, 35 Primary breeding habitat(s): Cliff/Cave/Rock Other habitats used: Widespread foraging in highlands   Summary of Concern White-throated Swift is widespread in mountain areas across the western United States, associated with cliffs and high rock formations. It has been raised to Watch List status by PIF because of long-term population declines; trends in New Mexico are uncertain.   Associated Species Peregrine Falcon (BC1), Prairie Falcon (SC2), Common Raven, Violet-green Swallow, Canyon Wren   Distribution White-throated Swift is a summer resident across most of the western United States, from southern Canada to southern Arizona and New Mexico, and from central California east to the Great Plains. Year-round, the species is resident in highland areas of the far southwestern United States and Mexico south to Central America.   In New Mexico, White-throated Swifts occur in the western two-thirds of the state, but are less common in the east where less suitable habitat exists.    Ecology and Habitat Requirements White-throated Swifts are associated with rocky terrain at middle to high elevations. They build their nests in crevices in cliffs, canyon walls and large rock formations, and forage widely in the air over adjacent open or forested areas. This species occupies nesting cliffs in coniferous and deciduous forest, shrubland and grassland. In New Mexico, it is most common in middle-elevation forest areas, but may be seen at higher or lower elevations when foraging or during migration (Ryan and Collins 2000).  White-throated Swifts are fairly common in New Mexico from March to September, rare in the far south in winter (Parmeter et al. 2002). Birds rarely land except to spend the night in large, communal roosts, and when nesting. Early nesting may begin in March, and continues through July. The species nests singly or semi-colonially, with nests placed on shelves in rock fissures and crevices (Ryan and Collins 2000).    Conservation Status Species Assessment   DISTRIBUTION  3  THREATS  3  GLOBAL POPULATION SIZE  4  LOCAL POPULATION TREND  3  IMPORTANCE OF NEW MEXICO TO BREEDING  2  COMBINED SCORE  15 White-throated Swift is a Species Conservation Concern, Level 2 species for New Mexico, with a total assessment score of 15. It receives a high vulnerability score of 4 from PIF for its relatively small population size.    Population Size Total population for New Mexico is unknown. PIF estimates a species population of 410,000, and that New Mexico holds about 6% of the species population, or about 24,000 birds.    Population Trend Overall trends are negative, though the population is expanding in some areas. Nationally, PIF gives this species a maximum score of 5 for population trend, which helps raise it to Watch List status. However, this score is not indicated by current BBS data for the United States and Canada (1966-2004 survey-wide, annual trend = -1.7, p = 0.29, n = 197). It should be noted that White-throated Swift is not considered well-sampled by BBS in any portion of its United States or Canadian range. In New Mexico, limited data suggest a sharp downward decline, but because of the small number of routes the species receives only a 3 from NMPIF for local population trend. BBS data for 1966-2004 are:      Annual Trend (%)  P-value  Number of Routes  New Mexico  -6.3  0.14  13  FWS Region 2  -1.4  0.64  40  Western BBS  -1.6  0.34  182   Threats White-throated Swifts are not highly vulnerable to most human impacts, and may benefit by using some man-made structures for nesting. Local impacts to breeding may occur from rock climbing, mining and quarrying, or removal of structures used for nesting. Overall, however, these impacts are probably minor. The degree to which swifts may be affected by pesticide use on breeding and wintering grounds is not known (Ryan and Collins 2000).    Management Issues and Recommendations No special management is needed for this species in New Mexico, but monitoring of nest colonies and roost sites should be conducted to determine population trends.     Species Conservation Objectives PIF Objectives The PIF North American Landbird Conservation Plan places White-throated Swift in the conservation action category Management. It sets a population objective of doubling the current population over the next 30 years.   NMPIF Objectives Devise and carry out surveys to assess the status and trends of this species statewide.  Seek to maintain or increase the present population.  Research potential causes for suspected declines in the state.   Sources of Information Parmeter, J., B. Neville, and D. Emkalns. 2002. New Mexico bird finding guide. New Mexico Ornithological Society, Albuquerque, NM.  Ryan, T. P., and C. T. Collins. 2000. White-throated Swift (Aeronautes saxatalis). In The Birds of North America, No. 526 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.