Wednesday, May 08, 2013

Red-winged Blackbird

Red-winged Blackbird - Agelaius phoeniceus

The Red-winged Blackbird males arrived in my backyard and in the bull rush marsh in the Elbow Valley Constructed Wetland late this year on May 4, 2013. 

The table below shows the date I first recorded and the last date I recorded a Red-winged Blackbird in my backyard in the last four years.  

Arrival Departure Total Days
2013 04-May
2012 31-Mar 20-Jul 112
2011 26-Apr 07-Aug 104
2010 17-Apr 15-Aug 121
2009 22-Apr 19-Jul 89

The departure in July or August seems sudden. The birds congregate in flocks and fly south, feeding on grain in fields along the way. While nesting they are mostly insectivores in the wild, but they attend my feeders daily during their nesting season. 

This male has chosen a spot in the marsh and will defend his turf.
They puff up their epaulets and broadcast their call regularly 

in what I imagine is a strong statement of ownership. 

The female usually lays four eggs. Incubation is by the mother alone for 10 to 12 days and then both parents feed the young for 10 or 11 days, after which the fledglings are on their own. The birds stay around the nesting site for another 10 to 14 days before they leave to forage for grain in fields. 
Red-winged Blackbird males can are polygamous. This is an exception in the bird world where 98% of species are monogamous. 

Puffing up the epaulets is mostly about territory and not apparently important in courtship. The red shoulder patches were covered up in a study and the females chose males based on nest location without any regard to whether the male had any color. The epaulets are definitely important for territory. The birds with the covered up shoulder patches lost their territory. Males puff up their epaulets as they fly to one of my feeders, which I presume means that the feeder is considered part of their territory. 

Red-winged Blackbirds will defend their nest from humans by aggressively flying toward the head of a person who comes too close. 


The Atlas of Breeding Birds of Alberta. 
Federation of Alberta Naturalists. 2007.

Baicich PJ, Harrison CJO. Nests, Eggs, and Nestlings of North American Birds. Princeton UP. 2005.

Fisher C, Acorn J. Birds of Alberta. Lone Pine Publishing. Edmonton. 1998.

Sibley David A. The Sibley Guide to Bird Life & Behavior. Alfred A Knopf, Inc. New York. 2001.

Tudge Colin. The Bird. Crown Publishers. New York. 2008.

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