Structure and Function Of Pair Duets In Yellow-Naped Amazons (Amazona Auropalliata)

EPA Grant Number: F6F70564
Title: Structure and Function Of Pair Duets In Yellow-Naped Amazons (Amazona Auropalliata)
Investigators: Dahlin, Christine
Institution: New Mexico State University - Main Campus
EPA Project Officer: Zambrana, Jose
Project Period: September 1, 2006 through September 1, 2008
Project Amount: $95,721
RFA: GRO Fellowships for Graduate Environmental Study (2006) RFA Text |  Recipients Lists
Research Category: Academic Fellowships , Biology/Life Sciences , Fellowship - Avian Behavior and Communication


I am conducting observations on wild populations of A. auropalliata in Costa Rica to observe natural patterns in duetting behavior. I conducted observations during February and March 2006 and will continue with observations in 2007 and 2008. I am primarily conducting observations at nesting territories where pairs duet.

Playback Experiments

I have already completed one playback experiment in which I played complete duets and duets that had the male or female notes removed. A complete duet represented a foreign pair invading the local pairs territory. A single sex duet represented an intruding bird that did not have a mate, and was possibly looking for a new one. The experimental design included three playback types for each pair:

  1. Complete Duet: Contains both male and female notes
  2. Single sex, male: Female notes removed, leaving 3-5 male notes.
  3. Single sex, female: Male notes removed, leaving 3-5 female notes.

I hypothesize that if duets serve a cooperative, territory defense function against all intruders, birds should have responded equally to playback types 1, 2 & 3. However, if duets are cooperative, but only intruding pairs pose a threat, they should have responded most strongly to playback type 1. If duets represent conflict, and are used to mate-guard (prevent their mate from getting extra-pair copulations), then birds should respond most strongly to a single intruder who has their same sex, and may be attempting to usurp their mate. My predictions are:

Playback Type

Hyp.1: Cooperative function against all intruders

Hyp. 2: Cooperative function against intruding pairs

Hyp.3: Conflict, mate guarding function


M & F response: strong

M & F response: strong

M and F response: weak


M & F response: strong

M & F response: weak

M response: strong, F: weak


M & F response strong

M & F response: weak

F response: strong, M: weak

During 2007 and 2008 I will continue with playback experiments in Costa Rica to further test duet function. Future experiments may test the importance of duet length, note composition or note order, among others.

Nest Box

A. auropalliata populations are declining primarily due to lack of good nest cavities and poaching in my area. I have begun a nest box program to investigate whether the parrots will utilize nest boxes if available, and whether playbacks at nest boxes can increase usage of them.


Cooperative communication signals, such as the leaping of male manakins during their courtship dance, are both inspiring and intriguing. Why would two organisms invest time and energy to signal together when they could signal alone? Presumably it takes more time and energy to signal with another organism, yet many species do so. Another type of coordinated display is a duet, when two or more organisms coordinate their communication. I have begun researching the function of duets in A. auropalliata, in which duets are given by pairs of mated birds.

Many functional hypotheses have been proposed for duets, but two primary hypotheses; joint resource defense and mate guarding, have found the most support. Since many duets are precisely coordinated, authors have hypothesized that they have a cooperative function, such as resource defense. Duets may also result from mate conflict. A bird may mate-guard by responding to their mate or singing simultaneously (duet), to announce that their mate is paired. I will investigate these hypotheses in A. auropalliata through a combination of long-term observations and playback experimentation.

Expected Results:

My expectation is that my observations and playbacks experiments will support a cooperative duet function, primarily against intruding pairs. I expect that duet research will also help me understand the importance of year round territories in A. auropalliata.

Supplemental Keywords:

Key Words: Parrot, communication, duet, cooperation, territory defense, nest,, Scientific Discipline, Ecosystem Protection/Environmental Exposure & Risk, Habitat, Environmental Monitoring, Ecology and Ecosystems, Biology, habitat species co-occurrence, animal responses, community composition, avian habitat quality, avian community dynamics, birds, breeding habitat

Progress and Final Reports:

  • 2007
  • Final