FAMILY CAPRI MULGIDAE I95 



On the mainland it ranges from southern Mexico through Central 

 America and South America to northern Argentina and northern 

 Uruguay. The most northern population in Mexico, Nyctibias g. 

 mexicanus, pale in color, is of maximum size, with the wing 297-307 

 mm. The race panamensis, which is smaller, and has two color phases 

 is found from western Panama south through Colombia (except east 

 of the Andes) to Ecuador and western Peru. The subspecies costari- 

 censis to the north, also named by Ridgway, from comparatively few 

 specimens seen is larger and apparently is a connecting group leading 

 to mexicanus. Birds from western Chiriqui are larger than most, and 

 appear intermediate toward costaricensis in size and color. 



Family CAPRIMULGIDAE: Goatsuckers, Chotacabras y 

 Tapacaminos 



The long- winged birds of this family are marked by short, weak 

 bills, and extremely large, broad mouths that open widely and so serve 

 to capture their food of flying insects. The plumage is soft, rather 

 loose, with a mottled pattern of inconspicuous colors. All are night- 

 birds, only the true nighthawks being active also by day. They are 

 known, therefore, mainly from the curious calls of the males heard 

 during the breeding season. The flight like that of owls is noiseless. 



The family is widely spread through the warmer countries of the 

 world, those that nest in colder regions being migratory to escape the 

 winter period when their insect food is not available. The common 

 countrywide Spanish name given collectively for all species of the 

 family is capacho, 3. word of uncertain derivation in aplication to a 

 bird. Another name, tapacamino is sometimes varied to ataja camino. 



KEY TO THE FAMILY CAPRIMULGIDAE 



1. Rictal bristles very small, barely evident 2 



With long, prominent rictal bristles 4 



2. Tail truncate, central rectrices equal to the lateral pairs, or slightly longer. 



Short-tailed nighthawk, Lurocalis semitorquatus noctivagus, p. 196 

 Tail emarginate, the central rectrices shorter than the lateral pairs 3 



3. White wing bar located at center of wing. 



Common nighthawk, Chordeiles minor, p. 204 

 White wing bar located nearer tip of wing. 



Lesser nighthawk, Chordeiles acutipennis, p. 199 



4. Rictal bristles with lateral filaments toward base; larger, wing more than 



200 mm Chuck-will's-widow, Caprimulgus carolinensis, p. 213 



Rictal bristles smooth, without lateral filaments at base; smaller, wing less 

 than 190 mm 5 



