Answers.Body: <p>Here, I recall one of the classic papers on <strong>Sound Attenuation and physical constrain</strong> <a href="https://link.springer.com/article/10.1007/BF00300047" rel="nofollow noreferrer"><code>(Wiley and Richards, 1970)</code></a>. <strong>Flat frequency</strong> sounds are advantageous for their low attenuation rate in <strong>open landscapes</strong> and high <strong>frequency-modulated sounds</strong> are advantageous in close forests where sounds get more resistance. Bird calls evolved in such a way that <strong>forest-dwelling birds have high-frequency modulation whereas grassland birds tend to have flat frequency vocalisations</strong> <a href="https://www.jstor.org/stable/4139395?casa_token=p_vYAyFeykMAAAAA%3Ae0fQcwFkhJ0_9Jq3rz_RTBpwvsQahG-RcGESY6G_N97OMoKvpW3-UxmtARVNS5Mmwdimz-vLcnd1RlZk3bP0NNHedrqjfv3I9ZbQ8BXRQP1N769Zees&amp;seq=1" rel="nofollow noreferrer"><code>(Boncoraglio and Saino, 2007)</code></a>. There are birds who use multiple call types depending upon purpose and physical situations. It will not be impossible for them to use different call modulation based on the physical environment. Therefore, it can be a nice domain to explore.</p>
  <p>PS. I don't know about any paper focused on call modulation in specific bird species based on open and close forests. If anyone finds it please post it here.</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2022-07-09T07:01:03.093Z
Answers.LastActivityDate: 2022-07-10T04:58:13.323Z
Answers.LastEditDate: 2022-07-10T04:58:13.323Z
Answers.UserDisplayName: Sougata Sadhukhan
Body: <p>Do birds alter their calls/songs when they are in open areas vs in closed areas (e.g., grassland vs forest)?</p>
  <p>This kind of habitat based response is seen a lot in active sensing animals (bats emit louder calls in open spaces, and also increase call duration) - but the 'selection pressure' to optimise echo detection is intuitively high.</p>
  <p>I know birds alter their calls and song in the presence of natural and anthropogenic noise (Lombard effect), but I haven't found any studies looking at short term alterations in bird vocalisation to the physical environment.</p>
  <p><em>Note</em>: I am not referring to geographic/evolutionary patterns  of bird song with physical habitat, but rather short-term, reversible alterations in song/call behaviour that individuals show.</p>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2022-07-07T07:44:07.980Z
Comments.Text: I smell a cool paper idea...
Comments.UserDisplayName: etgriffiths
Tags: <bird><birdsong><adaptation>
Title: Bird call/song adjustment to the physical environment
ThreadText: # Bird call/song adjustment to the physical environment
  
  (Asked by: username_0 on 2022-07-06)
  
  Do birds alter their calls/songs when they are in open areas vs in closed areas (e.g., grassland vs forest)?
  
  This kind of habitat based response is seen a lot in active sensing animals (bats emit louder calls in open spaces, and also increase call duration) - but the 'selection pressure' to optimise echo detection is intuitively high.
  
  I know birds alter their calls and song in the presence of natural and anthropogenic noise (Lombard effect), but I haven't found any studies looking at short term alterations in bird vocalisation to the physical environment.
  
  *Note*: I am not referring to geographic/evolutionary patterns of bird song with physical habitat, but rather short-term, reversible alterations in song/call behaviour that individuals show.
  
  **Tags:** bird, birdsong, adaptation
  
  > **Comments:**
  > **username_1**: I smell a cool paper idea...  
  
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  ## 1 answers
  
  ### Answer by username_2 on 2022-07-09. Score: 3
  
  Here, I recall one of the classic papers on **Sound Attenuation and physical constrain** [`(Wiley and Richards, 1970)`](https://link.springer.com/article/10.1007/BF00300047). **Flat frequency** sounds are advantageous for their low attenuation rate in **open landscapes** and high **frequency-modulated sounds** are advantageous in close forests where sounds get more resistance. Bird calls evolved in such a way that **forest-dwelling birds have high-frequency modulation whereas grassland birds tend to have flat frequency vocalisations** [`(Boncoraglio and Saino, 2007)`](https://www.jstor.org/stable/4139395?casa_token=p_vYAyFeykMAAAAA%3Ae0fQcwFkhJ0_9Jq3rz_RTBpwvsQahG-RcGESY6G_N97OMoKvpW3-UxmtARVNS5Mmwdimz-vLcnd1RlZk3bP0NNHedrqjfv3I9ZbQ8BXRQP1N769Zees&seq=1). There are birds who use multiple call types depending upon purpose and physical situations. It will not be impossible for them to use different call modulation based on the physical environment. Therefore, it can be a nice domain to explore.
  
  PS. I don't know about any paper focused on call modulation in specific bird species based on open and close forests. If anyone finds it please post it here.
  
  
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