16 August 2014 – Olive-backed Pipit

The tape-record of two birds at Immouzer by Arnoud van den Berg on 16 January 2012 was not accepted by MRBC. However, this record is reconsidered, and Arnoud sent the following: ‘For explaining why they were Olive-backed, I used the information on the website paper by Ralph Martins (www.avesrares.wordpress.com/2013/09/27/identification-of-olive-backed-and-tree-pipit-by-call): on Olive-backed vs Tree Pipit identification. I also sent the sound-recording to Ralph Martins himself. Today, I received his reply. Obviously, he agrees that there is no doubt for identifying the calls as belonging to Olive-backed. However, the wording of his reasoning is different from mine and more to the point. Therefore, I hereby enclose his reply, to attach to the record: I had a look at your recording. There is no doubt, the calls belong to Olive-backed Pipit. The MSF value (starting frequency in the center of the main part of the call) is in both distinct calls more than 8 kHz (8050 & 8500) – this is a good value for Olive-backed Pipit and out of range of Tree Pipit. The gradient is typical for OBP with a value of 14 and 18 (Tree Pipit around 5.9, max 13). Duration for one modulation is also typical with 11 ms

One thought on “16 August 2014 – Olive-backed Pipit

  1. The question is, if movements of the bird influence the frequencies of recorded calls (Doppler effect).

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