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2014 Southeastern Naturalist Notes Vol. 13, No. 2
J.A. Cox, C.D. Jones, J.W. Tucker, Jr., and G.F. Budney
An Unusual Song-like Vocalization Produced by Female
Bachman’s Sparrows (Peucaea aestivalis)
James A. Cox1,*, Clark D. Jones2, James W. Tucker, Jr.1, and Gregory F. Budney3
Abstract - We describe a new female vocalization for Peucaea aestivalis (Bachman’s Sparrow) that
may represent a type of female song. The vocalization has characteristics that are similar to the “excited”
or “flight” songs that male P. aestivalis produce, and similar song characteristics can be found
among other members of the genus, including one congener for which female singing is common.
Two marked female P. aestivalis were observed producing the vocalization as well as four unmarked
individuals that were paired with territorial males. A recording of one of these unmarked individuals
collected in 1989 is similar to the vocalizations observed for marked females. Field notes collected at
the time the recording was made suggested the “odd song” was produced by a female, and we provide
a sonogram of this new vocalization based on this recording. The vocalization appears to be rare and
may be difficult to link to external stimuli and social function .
Peucaea aestivalis Lichtenstein (Bachman’s Sparrow) has a widely celebrated song that
features elaborate male repertoires and male vocalizations that mimic the songs of other
species (Borror 1961, 1971; Mengel 1951; Murray et al. 2004). Bachman’s Sparrows also
produce a number of call notes that include: short, simple distress and alarm notes (pseet)
given when predators approach nests or fledglings; short chitter and hissing sounds (chay)
also given around nests and that may serve to distract potential predators; more-agitated,
twittering notes produced during the breeding season when conspecifics encroach on territories;
and crepuscular contact notes (including a high-pitched yip) given primarily in winter
(Weston 1968).
Although female Bachman’s Sparrows have been documented producing all call notes,
singing is thought to be restricted to males (Dunning 2006). In this note, we describe an
unusual vocalization produced by female Bachman’s Sparrows that differs from the many
call notes that have been described (Borror 1971, Dunning 2006) and may represent a form
of female singing. Most of our field observations stem from work conducted over the past
10 years with large, marked populations on the Wade Tract in southwest Georgia (30°47'N,
84°04'W; Thomas County; 273 marked individuals), Ft. Benning in west-central Georgia
(32°19'N, 84°48'W; Chattahoochee, Muscogee, and Marion counties; 68 marked individuals),
and Tall Timbers Research Station in north Florida (30°39'N, 84°14'W; Leon County;
87 marked individuals). The three sites contained mature pine forests that were burned
frequently (approximately 2–3-year return intervals), and sex for marked individuals was
assigned at capture by the presence of brood patches (females only), cloacal protuberances
(males only), and behavioral observations.
Although females are elusive, we observed two marked females on the Wade Tract
that attracted attention because their vocalizations were much longer in duration and
more complex than any of the call notes previously described. The vocalization resembled
the complex chattering that can be heard at the close of the “excited” or “flight” song produced
by males (Dunning 2006), and one marked female observed in April 2010 produced
1Tall Timbers Research Station and Land Conservancy,13093 Henry Beadel Dr.,Tallahassee, FL
32312. 2D.B. Warnell School of Forestry and Natural Resources, University of Georgia, Athens,
GA 30602. 3Macaulay Library, Cornell Lab of Ornithology, 159 Sapsucker Woods Road, Ithaca, NY
14850. *Corresponding author email - jim@ttrs.org.
Manuscript Editor: Wylie Barrow
Notes of the Southeastern Naturalist, Issue 13/2, 2014
2014 Southeastern Naturalist Notes Vol. 13, No. 2
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J.A. Cox, C.D. Jones, J.W. Tucker, Jr., and G.F. Budney
the vocalizations uninterrupted for approximately 5 sec. A second marked female produced
the vocalization for approximately 3–4 sec in September 2007. Both individuals
produced the vocalization from an exposed perch (making their unique color bands easy
to read) with their heads tilted in a position similar to that used by males when singing.
Dunning (2006) described the male’s excited song as a bubbling, exuberant combination
of notes that resembled the songs of a wren or Passerina cyanea L. (Indigo Bunting) produced
with unnatural speed. The vocalizations produced by the females that we observed
had similar complexity but qualitatively sounded more like the hastened song of Passerina
caerulea L. (Blue Grosbeak).
One of us (G.F. Budney) recorded an “odd song” of an unmarked individual near Abita
Springs, LA, in May 1989 that closely resembled the vocalizations produced by the two
marked females as noted here. This individual was paired with another unmarked bird that
produced a typical male song, and field notes collected at the time stated the odd vocalization
“… appeared to be the female of the pair.” The recording with audible field notes is
available on-line (http://macaulaylibrary.org/audio/62939) and was used to produce a sonogram
(Fig. 1; segment 0.18–0.22 in the recording). The length of the recorded vocalization
is abbreviated compared to the other vocalizations observed in the field but otherwise has
all the qualities of the vocalizations observed for the two marked females.
We observed similar vocalizations produced by unmarked individuals in the field on three
other occasions and believe that these also were female vocalizations because observations
occurred near known nests during the early part of the nesting season (April) and males were
observed singing typical songs near the putative females that produced the vocalization.
Males defend territories vigorously against conspecific males, and an observation of two
sparrows together without aggressive interactions is frequently used to assign paired breeding
status in this species (Sirman and Cox 2010, Tucker et al. 2006). One of the unmarked females
we observed appeared to produce the vocalization in response to playback of a male’s song at
Ft. Benning as the male approached the playback device. The male sang as well, while the female
continued to produce the vocalization for more than 5 sec.
The length and structure of the vocalizations observed for all six individuals differed
from chitter and hissing chay calls that females use near nest sites (Dunning 2006, Weston
Figure 1. Sonogram of a complex, song-like vocalization produced by a female Bachman’s Sparrow
near Abita Springs, LA (available online at http://macaulaylibrary.org/audio/62939; recorded by G.F.
Budney). The vocalization begins at 00:18 in the recording and continues for approximately 3 seconds.
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2014 Southeastern Naturalist Notes Vol. 13, No. 2
J.A. Cox, C.D. Jones, J.W. Tucker, Jr., and G.F. Budney
1968). Although the chitter call contains multiple syllables and might be repeated to form a
more lengthy vocalization, it lacks the diversity and range of pitches that we observed and
also descends in pitch once initiated (J.A. Cox and C.D. Jones, pers. observ.). The vocalizations
we observed ascended in pitch at times, contained more complex rhythms, and were
much longer in duration than any of the chitter vocalizations that we have observed.
Juvenile Bachman’s Sparrows produce a partial adult song a few months after hatching,
but juveniles are easily distinguished from adults until they attain adult plumage toward the
end of the breeding season. All observations of unmarked individuals occurred early in the
breeding season (April and May) when young birds (if present) would be easy to recognize
and lack the capacity to produce partial songs because of their age (J.A. Cox and C.D. Jones,
pers. observ.). The single female observed singing late in the breeding season in September,
when juveniles have been observed singing, was marked the previous year. In addition, the
partial songs we have observed for juveniles seem to be produced by males and include the
sustained introductory note that is characteristic of the primary song of adults. There was
no introductory note in the female vocalizations we observed.
We have difficulties classifying this vocalization definitively as a female song because
it could be an unusual type of extended call note. Most of our observations were recorded
near nests where agitated call notes would be expected. However, the vocalizations we observed
were much longer than any other calls known for this species, and one observation
in September was toward the close of the known nesting period for this region (March–September).
In addition, in five of the six observations reported (including marked individuals
and the individual recorded), the females uncharacteristically perched above ground and did
not display the agitated, wren-like bobbing typically performed when disturbed near nest
sites (Dunning 2006).
Another difficulty in classifying this vocalization stems from the generally limited
knowledge we have of female singing (Riebel et al. 2005), which has been documented
in several North American sparrows (Arcese et al. 1988, Illes and Yunes-Jimenez 2009).
Interspecific variation in the extent to which female singing occurs is great, and the circumstances
under which females sing often are rare and limited to specific social and ecological
conditions such as shortages of mates or nest sites (Riebel et al. 2005). Interestingly,
the genus Peucaea includes at least one member (P. ruficauda Bonaparte [Stripe-headed
Sparrow]) in which females sing more frequently than males and produce an extended,
complex song (Illes and Yunes-Jimenez 2009). Riebel et al. (2005) suggested that singing
in both sexes may be an ancestral condition in birds. This possibility makes classification
of this vocalization even more problematic because most members of the Peucaea produce
distinctive flight or excited songs that contain the complicated, rhythmic twittering that
characterized the vocalizations we observed for female Bachman’s Sparrows (DaCosta et
al. 2009). Given the broad occurrence of this type of vocalization among members of this
genus, the vocalizations that we observed could be a female song produced under very rare
circumstances, a vestigial type of ancestral female singing that is no longer firmly rooted
in a specific social function in Bachman’s Sparrows, or an extended type of agitated call.
Regardless, we hope additional recordings of this vocalization can be obtained and encourage
others studying this species to note the circumstances under which they encounter this
newly described female vocalization. Those studying other members of the genus Peucaea
also should try to determine whether females produce song-like vocalizations.
Acknowledgments. We thank Jeptha H. and Emily V. Wade for establishing the Wade
Tract Research Area. Financial support was provided by the Jelks Family Foundation,
the Nongame Wildlife Grants Program of the Florida Fish and Wildlife Conservation
2014 Southeastern Naturalist Notes Vol. 13, No. 2
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J.A. Cox, C.D. Jones, J.W. Tucker, Jr., and G.F. Budney
Commission, the Power of Flight Bird Conservation Program sponsored by the Southern
Company and the National Fish and Wildlife Foundation, and the Georgia Department of
Natural Resources. Two anonymous reviewers provided helpful comments on an earlier
draft of the manuscript.
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