Search

An Eastern Kingbird Tyrannus tyrannus was found on Barra, Outer Hebrides, on 29th September 2016 and remained until the following day. What is believed to have been the same individual was relocated at Bornish, South Uist, on 2nd October. This is the firs t British and the third European record, following sightings in Co. Galway in 2012 and 2013. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Field Ornithology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nest placement presumably reflects selection for secure sites to minimize failure. Most tests of this hypothesis, however, have failed to support it. We used artificial nests (ARTs) to experimentally evaluate nest-site-choice behavior by an open-cup-nesting bird, the Eastern Kingbird (Tyrannus tyrannus). In 2010 and 2011, we placed ARTs in trees in the riparian zone at Malheur National Wildlife Refuge, Oregon, USA, to test whether (1) characteristics describing the physical location in trees of used and unused ARTs differed, (2) used ART sites more closely resembled naturally chosen sites, (3) successful natural nests (NATs) and successful ARTs were similarly located along the major axis describing nest placement, and (4) unused ARTs resembled failed NATs. Used and unused ART sites differed, but unused ART sites were more similar to NAT sites. The latter unexpected result occurred because (1) unused ARTs were located at sites between more heavily used higher and lower locations and (2) most kingbirds nesting at lower locations used ARTs instead of building their own nest. In both ARTs and NATs, differences between successful and failed nests exhibited the same pattern for most nest-site variables, and the major gradient describing nest location was the same; successful nests tended to be placed on more vertically oriented branches that were placed closer to the top of the tree. Kingbird nest placement was thus selective. However, extensive overlap in the locations in trees of failed NATs and both successful and unused ARTs suggests that other factors, such as macrohabitat characteristics or prior experience of individual birds with particular nest sites, may have influenced success and/or decisions to use or reject nests in particular locations. Thus, consideration of phenomena beyond the nest site itself may be required to fully understand the process of nest-site choice in birds. [ABSTRACT FROM AUTHOR]

Harsh weather in spring presents energetic challenges to birds during migration and upon reaching the breeding grounds, and yet, birds often arrive well before breeding begins. We studied a population of Eastern Kingbirds in eastern Oregon from 2004 through 2007. Early arriving kingbirds faced the poorest weather conditions, and therefore we predicted that benefits of early arrival must exist to balance the presumed costs. Early-arriving kingbirds were more likely to both acquire a high-quality territory and to replace nests after failure. Early-arriving birds also bred early, and early breeding led to larger clutches and greater production of young. Early-arriving males also sired more extra-pair young than later arrivers. Our data suggest that arrival date is in part influenced by individual quality, and that arrival date has reproductive consequences, with the primary benefits of early arrival being the acquisition of a high-quality territory, early breeding, and increased probability of replacing failed initial nests. [ABSTRACT FROM AUTHOR]