Date of this Version
The Prairie Naturalist 43(3/4):92-99 ; 2011.
Male red-winged blackbirds (Agelaius phoeniceus) exhibit a difference in nest provisioning rates along an east-west gradient, in North America. North Dakota is located in the center of North America and harbors a large population of breeding red-winged blackbirds (RWBL). This location provided an opportunity to compare provisioning rates in the central U.S. with those reported for the eastern and western populations. We placed video cameras at RWBL nests to record male and female feeding trips. Thirty-four nests were located on territories with original males and 30 were on territories where a replacement (floater) male had taken over a territory after we removed the original male by shooting or trapping. Original territory owners were more likely to feed young, and males were more likely to feed at nests with older chicks, at nests with more chicks, and later in the breeding season. Red-winged blackbird parental provisioning patterns in North Dakota appear to be similar to those observed in eastern North America.