Alarm Calls and Information Use in the New Holland honeyeater
type: CreativeWork
description: Predation is a major source of mortality, resulting in strong selection on strategies to avoid being captured. Individuals have access to multiple sources of information on predation risk: they can detect danger directly themselves, and they can attend to behavioural cues or warning signals produced by others. Rapid responses are vital when hunted by aerial predators in particular, as split-second decisions can mean the difference between life and death. I studied New Holland honeyeaters, Phylidonyris novaehollandiae, as a model system to examine how alarm calls encode information about danger and to understand how this information is used by receivers. In Chapter 2, observational data showed that these honeyeaters produce multi-element, aerial alarm calls in response to flying threats. Male honeyeaters had more opportunities to detect threats than did females and showed a greater propensity to alarm call when presented with gliding model predators. In Chapter 3, a combination of observational data and model presentations demonstrated that aerial alarm calls encode urgency in both the number of elements, with more dangerous threats receiving more elements, and the acoustic structure of the first element. Playback presentations of alarm calls and video recordings to measure responses revealed that honeyeaters made extremely fast decisions about fleeing to cover based on the acoustic structure of the first alarm element, while the number of elements determined for how long they hid. These two chapters demonstrate that receivers have rapid access to detailed information about the type and degree of danger from conspecific alarm calls. In Chapter 4, I investigated how birds integrate personal information about danger with social information from alarm calls. Perched birds were faster to detect model predators than feeding birds, suggesting that they have greater access to personal information. Consistent with this, perched birds were less likely to flee to cover in resp…
abstract: Predation is a major source of mortality, resulting in strong selection on strategies to avoid being captured. Individuals have access to multiple sources of information on predation risk: they can detect danger directly themselves, and they can attend to behavioural cues or warning signals produced by others. Rapid responses are vital when hunted by aerial predators in particular, as split-second decisions can mean the difference between life and death. I studied New Holland honeyeaters, Phylidonyris novaehollandiae, as a model system to examine how alarm calls encode information about danger and to understand how this information is used by receivers. In Chapter 2, observational data showed that these honeyeaters produce multi-element, aerial alarm calls in response to flying threats. Male honeyeaters had more opportunities to detect threats than did females and showed a greater propensity to alarm call when presented with gliding model predators. In Chapter 3, a combination of observational data and model presentations demonstrated that aerial alarm calls encode urgency in both the number of elements, with more dangerous threats receiving more elements, and the acoustic structure of the first element. Playback presentations of alarm calls and video recordings to measure responses revealed that honeyeaters made extremely fast decisions about fleeing to cover based on the acoustic structure of the first alarm element, while the number of elements determined for how long they hid. These two chapters demonstrate that receivers have rapid access to detailed information about the type and degree of danger from conspecific alarm calls. In Chapter 4, I investigated how birds integrate personal information about danger with social information from alarm calls. Perched birds were faster to detect model predators than feeding birds, suggesting that they have greater access to personal information. Consistent with this, perched birds were less likely to flee to cover in resp…
author: McLachlan, Jessica Ruth
language: en
keywords: alarm call, information use, acoustic communication, anti-predator, social information
license: https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/d6f0b2b0-309c-45b4-b12c-f11613676f47/download
license: https://www.rioxx.net/licenses/all-rights-reserved/
date published: 2019-04-27
date modified: 2026-07-22T22:24:27Z
provider: Cambridge University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Cambridge

PropertyValue
property ID: DOI
value: 10.17863/CAM.33897