How to translate text using browser tools
1 May 2013 Provisioning Rate, Dietary Composition, and Prey Selection of Breeding Bobolinks and Grasshopper Sparrows
Ben R. Skipper, Daniel H. Kim
Author Affiliations +
Abstract

We examined parental provisioning behavior of 2 grassland obligate birds, Bobolink (Dolichonyx oryzivorus) and Grasshopper Sparrow (Ammodramus savannarum) in south central Nebraska. We assessed rates of food delivery (provisions * nestling_1h_1) and prey composition by using video recordings. We estimated arthropod availability from sweep net samples collected during 2 breeding seasons. We evaluated the effects of provisioning rate and prey composition on nestling quality inferred through nestling mass. We focused our efforts on lepidopteran larvae and orthopterans, as these orders comprised the bulk of identified prey deliveries. Total provisioning rates at 53 Bobolink nests and 32 Grasshopper Sparrow nests did not predict nestling mass for either species in either year. In one of 2 years, we observed a positive relationship between unidentified prey items and Bobolink nestling mass and a negative relationship between percentage of lepidopteran larvae and Bobolink nestling mass. These observed relationships are likely spurious, however. Parents of both species provided lepidopteran larvae at higher rates than were expected based on availability, and this particular result highlights the potential importance of dietary content to developing nestlings.

© 2013
Ben R. Skipper and Daniel H. Kim "Provisioning Rate, Dietary Composition, and Prey Selection of Breeding Bobolinks and Grasshopper Sparrows," Western North American Naturalist 73(1), 35-40, (1 May 2013). https://doi.org/10.3398/064.073.0103
Received: 18 August 2011; Accepted: 1 June 2012; Published: 1 May 2013
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top