If they move around during the first year, they continually change their song to match the adult males they are with... eventually they sing the final first-year song for the rest of their life...
It is conceivable that these first-year males might pick up the song of another species...
When INBUs occur with Lazuli and Painted Buntings, the INBU males tend to sing a similar song as the other bunting species...
It is thought to function in interspecific territoriality and aggression... laboratory experiments have shown that the females can sort out which male they should breed with, although Lazulis have been known to hybridize with Indigos...
Kimberly G. Smith
Distinguished Professor of Biological Sciences
Department of Biological Sciences
University of Arkansas
Fayetteville, AR 72701
Phone: 479-575-6359 fax: 479-575-4010
Email: <kgsmith...><mailto:<kgsmith...> ********************************
From: The Birds of Arkansas Discussion List [mailto:<ARBIRD-L...>] On Behalf Of Bill Shepherd
Sent: Saturday, July 15, 2017 10:44 AM
Subject: strange songs from Indigo Buntings
Early Thursday morning (July 13) I took a bird walk from the Pointe West Motel & Suites on Highway 187 in Carroll County, AR. This location is approximately one mile south of Beaver Lake Dam and more like half-a-mile south of the big water-filtration plant.
Near the motel I heard, I think, three Indigo Buntings singing. I didn't actually see any of them, but it certainly did look like good habitat for Indigo Buntings, and the tonal quality/timbre of the songs also fitted Indigo Buntings. Not far from there I also heard a Blue Grosbeak singing. Furthermore, I didn't notice any glades, much less any large ones, in the vicinity.
But the songs I heard Thursday were far from typical for Indigo Buntings. Instead, THEY SOUNDED MORE LIKE RUFOUS-CROWNED SPARROWS!
Forty-plus years ago I recall hearing (and maybe recording) similar songs from Indigo Buntings that lived cheek-by-jowl with Rufous-crowned Sparrows on the south-facing slope of Magazine Mtn. It was easy then to theorize that infant male buntings had heard lots of Rufous-crowned Sparrow song from their nests and that that experience influenced how they sang when they became adult.
But my experience Thursday morning now makes me strongly question my previous interpretation of what I heard on Magazine way back when. Unfortunately, I didn't have with me any equipment for recording the songs that I heard Thursday morning. Do the Indigo Buntings on Magazine still sing like RCSs? Do they, Don?
Bill Shepherd 2805 Linden, Apt. 3 Little Rock, Arkansas 72205-5964 <Stoneax63...><mailto:<Stoneax63...> (501) 375-3918