Andean Cock-of-the-rock Rupicola peruviana nest under a bridge.
Transcripción
Andean Cock-of-the-rock Rupicola peruviana nest under a bridge.
COTINGA 9 Andean Cock-of-the-r ock Rupicola peruviana nest under a bridge Vinicio Pérez and Jane A. Lyons de Pérez Según varios estudios y observaciones, la hem bra del Gallo de la Peña Rupicola p eruviana siem pre construye su nido de form a vertical en rocas o piedras dentro de cuevas o quebradas. Se describe aquí u n nido de esta especie construido de form a horizontal dentro de u n p u en te de cem ento sobre un río cerca de Mindo, Ecuador. Se observó el sitio d u ra n te unos 48 días, período d u ra n te el cual la hem bra y dos pichones ocuparon el nido. Andean Cock-of-the- r ock nesting bridge (J. A. Lyons de Pérez) Andean Cock-of-the- r ock nest (J. A. Lyons de Pérez) On 22 S eptem ber 1997, n e a r Mindo, north-w est Ecuador, VP discovered an A ndean Cock-of-ther ock R upicola peruviana n e st w ith two young in it and a tte n d e d by a n a d u lt female. The n est was placed on a crossbeam u nder a concrete bridge. The ad u lt fem ale h ad been observed by VP on 8 Sep tem b er near th e bridge, and a sub seq u en t search revealed th e nest-site. It was c. 5 m above th e river, directly over its m id-point and w ell-hidden w ith only a few sm all sticks visible. The fem ale w as v is ible as a d ark lum p on the crossbeam , and usually only one w ing or the head was visible from certain angles. The n est was c. 1 m below th e top and 5 m from the sides of the bridge, an d th u s appeared extrem ely w ell-protected from m am m alian p re d a tors. T he n est-site is 5 km dow nstream from an active lek of th e species. O ther n ests have been reg u larly discovered a t various sites u p stream of th e bridge. S ubsequent visits to the n est on 26 Sep tem b er (at 10h 00), 27 S eptem ber (at 16h00) and 28 Septem ber (at 10h30) alw ays found th e fem ale on th e nest. U nless disturbed, she rem ained there. Once disturbed, she would fly directly into shrubs on th e riverside, on two occasions rem aining th e re u n til we left. On th e th ird visit, she stayed only briefly in th e sh ru b b ery before re tu rn in g and se t tlin g on th e nest, facing us. The a rea aro u n d th e bridge is m ostly cut-over secondary forest, w ith some p rim ary forest 0.5 km away. T here are several farm s along th e road a t th e bridge w ith livestock which cross th e bridge to graze ad jacen t grassy areas. People reg u larly u ti lise th e riv er a t th e bridge and birds are h u n ted for food by some local people. T h e n e s t w as o b serv ed d u rin g su b se q u e n t weekly visits u n til 12 Novem ber 1997. Each time, th e fem ale was on th e n est w ith th e two young birds, of different sizes and one obviously a male. As we approached, th e fem ale would fly to thick vegetation ad jacent to th e bridge. Once, she called and quickly re tu rn e d to th e nest, b u t on all other occasions rem ain ed hidden and quiet in th e veg etation. On 8 November, 48 days after th e n est was discovered, the chicks were large and obviously near fledging. On 12 November, th e n est was em pty and no b ird s w ere seen. This is a p p aren tly th e first record of eith er spe cies of R upicola n estin g on a bridge. According to th e available lite ra tu re , both R upicola p eruviana and R. rupicola typically place th e ir n ests on rock 81 COTINGA 9 A n d e a n C o c k - o f - t h e - r o c k n e s t u n d e r a b r id g e faces am ong b o u ld ers in caves, crevices or r a v in es1,3,4,5. The fledging period for th e young birds u n d er th e bridge was a t le a st 4– 6 days longer th a n th e 42– 44 days described in th e lite ra tu re 2,5. 3. M eyer de Schauensee, R. & Phelps, W. H., Jnr. (1978) A g u id e to the b ird s o f Venezuela. Princeton: Princeton U niversity Press. 4. Ridgely, R. S. & Tudor, G. (1994) The birds o f S o u th Am erica, 2. A ustin: U niversity of Texas Press. 5. Snow, D. (1982) The co tin g a s. Ith a c a , NY: Cornell U niversity Press. R efe r e n c e s 1. Hilty, S. L. & Brown, W. L. (1986) A guide to the birds o f Colombia. Princeton: P rinceton U ni v ersity Press. 2. M anosalvas N icolalde, R. (1993) A cerca del cortejo, la anidación y la dieta del Gallo de la Peña, Rupicola p e ru v ian a sanguinolenta en el bosque nublado de M indo, Ecuador. U npub lished thesis, Pontificia U niversidad Católica del Ecuador, F acultad de Ciencias E xactas y N aturales. V in ic io P é r e z a n d J a n e A. L yon s de P érez Eloy Alfaro 3651, Casilla Postal 17-17-717, Quito, Ecuador. 82