l82 BIRDS OF THE REPUBLIC OF PANAMA — PART 2 



Male and female, taken on the Quebrada Carriaso, on the southern 

 slope of the Cerro Azul, April 25, 1949, had the iris hazel; bill black ; 

 cere neutral gray ; claws black. 



A female shot at Sona, Veraguas, May 28, 1953, had the iris light 

 cinnamon-brown, exactly the same shade as the feathers of the crown. 



Measurements. — Males (6 from Panama, Costa Rica, and Vera- 

 cruz) wing 223.0-236.0 (229.5), tail 119.1-131.5 (125.7), oilmen 

 from cere 19.5-23.2 (21.2) mm. 



Females (7 from Panama and Guatemala), wing 228-242 (235.0), 

 tail 121.4-134.2 (126.4), culmen from cere 20.7-22.7 (21.7) mm. 



Resident. Local, in the lowlands of the Pacific slope. Recorded 

 from Chiriqui (locality uncertain), Veraguas (Sona) ; Herrera (Pa- 

 rita, Santa Maria) ; Canal Zone (Ancon, Balboa, Paraiso) and 

 eastern Panama (Pacific side of Cerro Azul) ; to the lower Chagres 

 Valley on the Caribbean side (Juan Mina) . 



These interesting owls are found in open areas of grass and marsh- 

 land, where thickets and low trees offer shelter at need. They rest 

 regularly in low trees, but nest on the ground. When seen clearly the 

 long feather horns are prominent, as is the distinctly buff plumage. At 

 Juan Mina I have seen them at sunset flying low over marshes, quarter- 

 ing the broad expanses of grasses and other floating vegetation. In 

 other areas I found them resting during the day on low perches, some- 

 times in lines of trees that separate open fields. Small birds gather to 

 scold them, so it appears that they are definitely predatory. I have 

 never identified a nocturnal call of this owl. 



At Juan Mina, Canal Zone, Enrique van Horn showed me a nest on 

 December 17, 1955, placed on the ground in an open space in a citrus 

 grove. The location was on a slightly elevated section where grass and 

 weedy plants grew to a height of more than a meter. The 2 white 

 eggs were placed on flattened plant growth, with no semblance of a 

 formal nest depression, but were overhung by the surrounding herbage 

 to give a measure of seclusion. A parent bird flushed from the nest, 

 and perched in a nearby tree to watch as I took several photographs 

 and packed the eggs for removal. The nest area was so well located 

 that it was dry in spite of a tremendous rain the previous night that had 

 left standing water in all depressions. The site appears to be one that 

 these owls use regularly as Dr. F. A. Hartman (Condor, 1956, p. 73, 

 fig. 1 ) recorded 2 young in down on January 8, 1953, and on Janu- 

 ary 5, 1962, van Horn found there 2 young, old enough to sit erect in 

 the nest. 



One of the 2 eggs collected was fresh. In the other incubation had 



