Within the field of Behavioral Ecology,
there are many topics that pique my curiosity, but my main
interest is the problem of how and why birds use song and
other vocalizations. Studying communication is a way to pursue
many questions simultaneously, as it is the mediator of social
interactions in many settings and situations. I first became
interested in song in particular when I read about the complexities
of song development in brood parasites (Payne 1998) and about
intraspecific song dialects (as in Treisman 1978), but it
was during my undergraduate research when I was able to listen
to male American Redstarts in the field when my interest became
I am interested in
how females make pre-breeding choices about males and territories,
and how song can affect these choices. In particular, I
want to know whether song can affect a female's choice to
stop migrating. Can she be "persuaded" to stop early if
she hears an appropriate or "attractive" song? While working
as an undergraduate assisting Sarah Mabey (past graduate
student in the Migratory Bird Research Group), I became
involved in her doctoral project on captive Eastern Kingbirds,
Tyrannus tyrannus, which examined sex differences
of patterns of migratory activity. A bit of serendipity
resulted after she noticed a decrease in nocturnal migratory
activity in females after males began to sing, and a corresponding
increase when the singing males were removed. She noted
that "the onset of breeding behavior and concurrent decrease
in male activity suggest that the termination of spring
migration is more strongly controlled on an endogenous level
for male Eastern Kingbirds than it is for females. It is
possible that the presence of males in breeding disposition
may be an important Zietgeber for the termination of vernal
restlessness in females"(Mabey dissertation 2002). I plan
to address this problem in the following hypotheses in a
research design with laboratory and field components.
use song as an exogenous cue to terminate migration in the
absence of other cues.
Prediction: If females use
song as a cue to stop migration in the absence of other
cues, then females prematurely exposed to song will terminate
migratory restlessness before females that are never exposed
to song or exposed to song later.
Hypothesis 2: Song
is one of several important exogenous cues for the decision
to terminate migration in females, including habitat and
Prediction 1: A female that
is closer to a general breeding site goal will be more likely
to be influenced by song cues than females that are a long
way from their breeding grounds.
Prediction 2:Resident and
partial migrant species will be more likely to orient towards
song cues than long-distance migrants at a coastal stopover
site on the Gulf of Mexico.
As an undergraduate
I was hired as a field assistant for Rob Smith's (past graduate
student in the Migratory Bird Research Group) doctoral work
on how parental energetic arrival condition affects reproductive
success with American Redstarts in the Upper Peninsula of
Michigan. The summer after my sophomore year I worked primarily
as a mist-netting assistant (with some arthropod collection).
The following summer I returned to Michigan with the intent
of studying American Redstart song while fulfilling my duties
as a field assistant, which included foraging observations,
nest searching and monitoring, and target-netting and resighting
In my undergraduate
thesis I used my field observations of American Redstarts
to test the current hypotheses about the function of song
modes in this species. American Redstarts have two song
modes, a repeat mode that is sung early in the season and
serial mode that is sung after copulation. Current literature
suggests that the repeat mode, the only song sung when females
arrive on the breeding grounds, is a female directed song
(Lemon et. al 1994). However, I found that repeat mode is
also the only song sung during male-male territory formation
and can illicit aggressive responses to playback in males.
I also found that females paired with serial sing males
(not all males proceed to serial mode- see Sherry & Holmes
1997) had earlier clutch initiation than females not paired
to serial singing males. These observations led me to generate
a hypothesis for future tests, namely that serial singers
have some advantage, perhaps physiological as song production
is tied to hormone levels, that affects female choice. I
also believe that the link between male-male aggression
and repeat mode should be more closely examined. I presented
these findings and hypotheses at a poster session at the
North American Ornithological Conference in New Orleans
in September 2002.
song mode and parentage in American Redstarts
Can different variables
such as rate, individual variation, or conspecific diversity
affect the effectiveness of a song as a cue to end female
Lemon, R.E., S. Perreault, & D.M.
Weary. 1994. Dual strategies of song development in
American Redstarts, Setophaga ruticilla. Animal
Mabey, S.E. 2002. Sex-based differential
migration:An examination of proximate and ecological
consequences. Ph.D. dissertation, University of Southern
Payne, R.B., L.L. Payne, & J.L. Woods.
1998. Song learning in brood parasitic indigobirds
Vidua chalybeata:song mimicry of the host species.
Animal Behaviour 55:1537-1553.
Sherry, T.W. & R.T. Holmes. 1997.
The American Redstart. The Birds of North America.
No 277. A. Poole and F. Gill, eds.
Treisman, M. 1978. Bird song dialects,
repertoire size, and kin association. Animal Behaviour
Department of Biological Sciences
The University of Southern
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