A 



Arizona 



UNITED 



New 

 Mexico 



tat had already driven them from the United States, 

 though the birds had lived in the southwest until the 

 early 1900s [see map on this page]. Early naturalists 

 had spotted them fairly often in parts of southern 

 and western Texas, southwestern New Mexico, and 

 southeastern Arizona. But heavy livestock grazing 

 and fewer natural fires had turned grasslands into 

 scrublands. Wet savannas, moreover, had been con- 

 verted to cropland. The last sighting of aplomado 

 nesting pairs in the U.S. was in the 1950s. 



But Keddy-Hector did find aplomados in Mex- 

 ico. They stood out brightly against the blue sky 

 in the coastal state of Veracruz, perched above the 

 rich grasslands in the tops of lone acacia trees. They 

 laid their eggs in the abandoned nests of other large 

 birds and in bromeliads, or air plants [see photograph 

 on opposite page]. And, like all tropical falcons, they 

 ate insects. 



Keddy-Hector showed, however, that insects 

 make up only a small part 

 of the aplomado diet — 

 appetizers, you might 

 say, though still impor- 

 tant to young, inexperi- 

 enced falcons learning to 

 hunt. The staff of life for 

 aplomados proved to be 

 other birds: a myriad of 

 resident and migratory 

 species passing through 

 the falcon territories. 

 The aplomados could 

 catch these prey from 

 standing starts in treetop 

 perches. And, once in 

 the air, they could easily 

 close a quarter-mile gap 

 in pursuit of, say, a pass- 

 ing flock of doves. 



Hunting is not the on- 

 ly chance for aplomados 

 to show off their talent 

 for stupendous flying. 

 They are fiercely territo- 

 rial and seek to drive 



away any large bird that enters their turf. Highest 

 on their list or undesirables are other aplomados; 

 nests are therefore wiciely spaced across the land- 

 scape, usually miles apart. Other species singled out 

 for special disdain are hawks, owls, and ravens — and 

 for good reason. The low trees of the savanna offer 

 little protection from such predators for aplomado 

 nestlings. The best strategy for parent aplomados, 

 then, is to attack on sight, giving the territory itself 

 a hostile reputation. Whenever they attack, the aplo- 



STATES, 



, ic. A, 



Current known aplomado range 

 Historically known aplomado range 



Texas 



Current and historically known ranges of aplomados in the 

 U.S. and Mexico are plotted above. Colored question marks 

 indicate historical ranges that are not well documented. The 

 small areas in Texas marked as current ranges are regions 

 where aplomados have been reintroduced. The species also 

 occurs in Central and South America. 



mados also steal any prey the intruders may be car- 

 rying, giving them yet another reason to stay away. 



By the late 1970s, the loss of breeding aploma- 

 dos in the U.S. had stirred enough regret among 

 conservationists that they began taking action. 

 Eggshell thinning caused by DDT in eastern Mex- 

 ico was also detected by Keddy-Hector, attracting 

 more attention. People began wondering whether 

 the aplomado in Mexico might be going the way 

 the peregrine had two decades earlier: total loss of 

 breeding pairs in the eastern U.S. The Peregrine 

 Fund, an organization founded in 1970 by one of 

 us (Cade), was already restoring peregrines to their 

 native habitat by releasing captive-bred young. So 

 it was a small step to suggest that aplomados might 

 benefit from similar intervention. 



With the cooperation of the Mexican govern- 

 ment, John Langford, a biologist at the Chihuahuan 



Desert Research Insti- 

 tute in Alpine, Texas, and 

 his coworkers brought 

 eight young aplomados 

 from Mexico back to 

 Texas. There, in 1982, 

 the first captive-born 

 hatchling emerged. In 

 1990 more birds from 

 Mexico were bred, in or- 

 der to enrich the genet- 

 ics of the original seed 

 population. After fits and 

 starts with artificial insem- 

 ination, rearing meth- 

 ods, and pilot releases, 

 more than fifty young 

 aplomados were being 

 raised and seemed ready 

 for release. Conserva- 

 tionists were finally in a 

 position to make the first 

 large-scale attempt at 

 restoring the species to 

 nature. But where? 

 The savannas of coast- 

 al southern Texas seemed to offer the best chance 

 for re-establishment. The region had included vast 

 savannas at the time of the Spanish settlement in 

 the 1600s. Brush invaded, though, and by the ear- 

 ly 1900s, most of southern Texas w as either devel- 

 oped as farmland or blanketed in brush. But even 

 with such large-scale loss of habitat, aplomados bred 

 just north of Brownsville, Texas, until the mid- 

 1 940s. The final loss of the species in southern Texas 

 coincided with the arrival ofDDT in 1947 for cot- 



May 2006 NAT UKAl HISTORY 



