Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

Diet and Hunting Behavior of the Crane Hawk in Tikal National Park, Guatemala

Jason Sutter, Walter E. Martínez A., Francisco Oliva T., Nery Oswaldo J. and David F. Whitacre
The Condor
Vol. 103, No. 1 (Feb., 2001), pp. 70-77
Stable URL: http://www.jstor.org/stable/1369679
Page Count: 8
  • Read Online (Free)
  • Download ($12.00)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Diet and Hunting Behavior of the Crane Hawk in Tikal National Park, Guatemala
Preview not available

Abstract

We studied the breeding diet and hunting behavior of Crane Hawks (Geranospiza caerulescens) in Tikal National Park, Petén, Guatemala in 1994 and 1995. We observed 227 prey items while conducting observations at six nesting attempts, and during opportunistic sightings in the breeding season. Among 181 identified prey items, rodents comprised 47.5%, lizards 19.9%, frogs 16.0%, bats 6.6%, birds 6.1%, and snakes 2.8%; a juvenile skunk also was represented. Rodents accounted for 77% of estimated biomass, including at least eight species representing terrestrial, cursorial, and arboreal habits. More than half of all prey items weighed <20 g, but 40% weighed >50 g; many were nocturnal species presumably taken from daytime hiding places. We observed hunting attempts in all strata of the forest and in several forest types. Hunting behavior included still-hunting from a perch and probing with head or feet in holes, bromeliads and other epiphytes, palm leaf axils, crotches of branches, behind bark in living and dead trees, and in puddles. Compared to other raptors studied at Tikal, the Crane Hawk had a moderately broad food niche that overlapped most with other raptors deemed dietary generalists. However, the Crane Hawk's unique anatomical features and hunting behavior enabled it to capture diurnally reclusive prey presumably unavailable to many other raptors, thus facilitating relatively low dietary overlap. /// Estudiamos la dieta y el comportamiento de cacería del Gavilán Ranero (Geranospiza caerulescens) durante 1994 y 1995 en el Parque Nacional de Tikal, Petén, Guatemala. Observamos 227 presas durante observaciones de seis nidadas y otras observaciones oportunas en la estación reproductiva. De 181 presas identificadas, roedores constituyeron el 47.5%, lagartijas 19.9%, ranas 16.0%, murciélagos 6.6%, aves 6.1%, y culebras 2.8%; un zorrillo infantíl también fue representada. Roedores constituyeron el 77% de la biomasa estimada, e incluyó al menos de ocho especies con hábitos terrestres, cursoriales, y arbóreos. Más de la mitad de las presas pesaron <20 g, pero el 40% pesaron >50 g; muchas fueron especies nocturnas, por presunción capturadas de escondites durante el día. Observamos intentos de cazar por todas partes del sotobosque y en el dosel en varios tipos de bosque. El comportamiento de caceria incluyó posando quieto en una percha, y buscando con cabeza y pies entre hoyos, bromélias y otras epífitas, hojas de palmas, bifúrcaciones de ramas, detrás de la cortesa de árboles ambos vivos y muertos, y en charcos. En comparación con otros rapaces estudiados en Tikal, el Gavilán Ranero tenía un nicho alimenticio algo amplio que coincidió más con rapaces considerados como generalistas dietéticos. Sin embargo, la anatomía singular del Gavilán Ranero y su comportamiento de cacería permite la captura de presas con hábitos diurnamente secretos que probablemente son indisponibles a otras rapaces, así facilitando menos coincidencia de la dieta entre ellos y los demás especies.

Page Thumbnails

  • Thumbnail: Page 
70
    70
  • Thumbnail: Page 
71
    71
  • Thumbnail: Page 
72
    72
  • Thumbnail: Page 
73
    73
  • Thumbnail: Page 
74
    74
  • Thumbnail: Page 
75
    75
  • Thumbnail: Page 
76
    76
  • Thumbnail: Page 
77
    77