An observation of parental infanticide in Dickcissels (Spiza americana): video evidence and potential mechanisms

Project Type: Graduate Student
Funds awarded in 2015: $9,977.00
Projected End Date: 12/31/2018
Grant Recipient: University of Illinois
Region: North Central
State: Illinois
Graduate Student:
Faculty Advisor:
Dr. James Miller
University of Illinois
Description:
Brood reduction by parents via infanticide is considered rare in passerine birds; however, this behavior may be underreported because of the difficulties observing behaviors at the nest and because researchers tend to attribute partial nestling loss to other causes. Here, we report a confirmed incidence of parental infanticide by Dickcissels (Spiza americana). While video-recording parental behavior, we documented a 4-day-old nestling being removed by a female Dickcissel. This bird was also observed brooding and feeding, so this event was likely a parental infanticide. We subsequently examined monitoring data from 162 hatched Dickcissel nests across 2 breeding seasons to identify instances of unexplained partial nestling loss, which could potentially be attributable to infanticide. Our data indicate that 9.1–12.7% of hatched nests experienced these events. Infanticide by genetic parents could (1) benefit survival of remaining brood mates by reducing food requirements, disease, or predation risk; (2) represent responses to cuckoldry or intraspecific brood parasitism; (3) represent cases of mistaken chick identity; or (4) be triggered by unusual stressors. We recommend that ecologists monitoring bird nests consider infanticide as a possible explanation for partial nestling loss.
Type:
Peer-reviewed Journal Article
File:
Authors:
Jaime J Coon, University of Illinois at Urbana-Champaign
Scott B Nelson, University of Illinois at Urbana-Champaign
Amy C West, University of South Dakota
Iris A Bradley, University of Illinois at Urbana-Champaign
James R Miller, University of Illinois at Urbana-Champaign
Target audience:
Researchers
Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.