Hello James
Your comments are very much appreciated. One thing that has always bothered
me is that everyone seems to assume that the difference in alarm call is due
to the TYPE of threat. Logically, it could be due to the DISTANCE or even
DIRECTION of the threat? These sorts of issues would have to be addressed
in any proper study, I think.
I will try and get hold of a copy of the Emu article. Thanks again.
Andrew Thelander
Cooran, Qld
----------
> From: James Davis <>
> To: Sandra Wilson <>
> Subject: Re: CALLS OF THE NOISY MINER
> Date: Thu, 13 Aug 1998 16:59:38 +1000 (EST)
>
>Sandra:
>
>Unfortunately, there is a lot of unconfirmed information circulated in the
>lay literature. Although I am not an expert on the Noisy Miner, I am
>familar with the species and somewhat knowledgeable within the topic of
>animal communication. I offer the following summary comments:
>
>1) As a rule, most social species (including birds) emit between 15 to
>30 different vocalizations - sounds that can be identified as belonging to
>a particular acoustical and/or functional category.
>
>2) However, many species may also use what is called graded signalling.
>If they do, then they will varying one or more aspects (acoustical
>features) of their voice - such as repetition rate, frequency, cadance,
>etc.. For example, as a bird gets more excited the pitch of its voice may
>rise and the rate of calling may also increase. At any point along such a
>continuum would you classify any particular sound as a distinct call? I
>would not unless it can be shown that the listener partitions the sounds
>into meaningful categories. With this said, it is also true that changes
>in volume, frequency, etc, can convey information (e.g. when you are angry
>you may scream and this sudden increase in volume will draw the attention
>of people around you regardless of your words, etc.). I would not,
>however, classify the word "help" as necessarily having a different
>meaning because it is scream louder or softer. Would you?
>
>3) I have heard people say that Noisy Miners have two or three
>different alarm calls (acoustically distinct calls) that are associated
>with different types of predators (hawk, ground predator, and snake).
>This is possible, but I have not been able to confirm this. It is also
>possible that the miner's alarm calls fit along a continuum - if so you
>could argue that they have an infinite number of alarm calls. Few people
>would agree to this interpretation. You must also keep in mind that in
>many species, young birds learn to give particular alarm calls
>under different circumstances by observving the behaviour of
>other birds.
>
>4) Birds that can mimic sounds are capable of producing a large number of
>distinct "calls", but in most species it is unlikely if any of these
>"copied" or "invented" sounds convey a unique message. I don't believe
>that the Noisy Miner mimics sounds, but I am open to the possibility.
>
>5) Doug Dow's 1975 paper (published in the Emu) lists a
>number of different calls and behaviours of the Noisy Miner.
>
>I hope this helps.
>
>Dr. Wm. James Davis, Editor
>Interpretive Birding Bulletin
>
>
>On Tue, 11 Aug 1998, Sandra Wilson wrote:
>
>> In her latest "Bird Talk" column in a Sunshine Coast newspaper, Valda
McLean
>> comments that a keen raptor observer once told her that the noisy miner
has
>> fifty (50) different calls and he had learnt what each one meant.
>> I am interested in this. Does anyone know of any scientific studies into
>> the calls of the noisy miner? I know it's not one of our favourite
birds!!
>> Regards.
>> Andrew Thelander
>>
>
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