Bird Conservation International

Table of Contents - 2007 - Volume 17, Issue 03  

Research Article

Time budgets and habitat use of White-naped Cranes Grus vipio in the Ulz river valley, north-eastern Mongolia during the breeding season

Ute Bradtera1 c1, Sundev Gombobaatara2, Chuluunbaatar Uuganbayara2, Tracy E. Graziaa3 and Klaus-Michael Exoa1

a1 Institute of Avian Research, An der Vogelwarte 21, 26386 Wilhelmshaven, Germany

a2 Department of Zoology, National University of Mongolia, P. O. Box 537, Ulaanbaatar 210646A, Mongolia

a3 Mississippi Sandhill Crane National Wildlife Refuge, 7200 Crane Lane, Gautier, MS 39553, U.S.A.

Abstract

Habitat loss and degradation are critical threats for the globally threatened White-naped Crane Grus vipio. We estimated the size of the area used per day and the time budgets of parental and non-parental White-naped Crane pairs in north-eastern Mongolia during 2000 and 2001. Six parental crane pairs used an area of 11–155 ha per day. The maximum distance of a focal parental crane from the roosting-site was 3,030 m. Habitat conservation measures for breeding White-naped Cranes need to be targeted to within at least 3 km of the roosting-site or nest-site. Parental cranes spent 79.6 ± 4.8% of the daylight period foraging and had reduced preening and resting behaviour to 4.4 ± 1.9%. Pairs without juveniles showed a pronounced period of resting and preening behaviour during midday, which was absent in parental cranes. This indicates that parental cranes may be time-stressed. We conclude that increases in feeding-related activities (e.g. caused by a decrease in food availability) are likely to be at the expense of parental vigilance. Conversely, increases in vigilance (due to e.g. increased disturbance) may have a negative impact on feeding-related activities. Both increases can potentially negatively affect reproductive success in this Vulnerable species.

(Received February 14 2006)

(Accepted October 31 2006)

Correspondence:

c1 Author for correspondence. e-mail: verandering@gmx.de