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Franck Hollander
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Weibl. Fichtenammer
Guten Abend,
Wie schön, dass wieder Fichtenammern in Deutschland auftauchen ! Aber soll man seit Hellquist (2016)* nicht noch vorsichtiger sein mit der Bestimmung von weiblichen Fichtenammern ? Ist es eigentlich überhaubt möglich, ohne DNA-Proben? Nur eine Frage...
VG, Franck
Concluding summary
Admittedly, any attempts to define the demarcation and extent of overlap between females in Yellowhammer and Pine Bunting, including those in this paper, are to some extent speculative in the absence of DNA establishing the identity of studied birds. The extensive hybridization further leads to inevitable difficulties in drawing the line between pure birds and back-crosses that are similar to either species.
There are indications that absence of yellow plumage hues is not enough to identify female Pine Buntings – at least not in the field and outside the normal range of the species. There is convincing evidence that Yellowhammers can lack yellow in the primaries and, at least in field conditions, on the body. The yellow on the underwing can be faint and hard to assess. As hybrid males can lack yellow plumage hues entirely, it is very likely that the same goes for hybrid females. That male Pine Bunting records in Finland and Sweden have been followed during the last decade by a series of female candidates lacking yellow but showing heavy streaking and less rufous below than normal in Pine Bunting has raised suspicions that Yellowhammers and/or hybrids are involved. Male hybrids reach Scandinavia regularly, and it is likely that cryptic female hybrids occur as well.
In order to avoid distortion of vagrancy patterns and detect more hybrids or atypical Yellowhammers, it is suggested that the following is taken into account along with presence/absence of yellow when assessing female Pine Bunting claims:
• very few Pine Buntings entirely lack rufous in the supercilium, whereas extensive rufous in the supercilium, in the submoustachial and lateral throat-stripe and on the throat seems to rule out Yellowhammer (checking this feature often requires examination in the hand, in particular when the plumage is fresh);
• Pine Buntings usually show extensive rufous below, and it is uncertain whether pure birds ever show as limited rufous as in many Yellowhammers;
• extensive yellowish or flesh hues on the lower mandible indicate Pine Bunting;
• limited white on the fifth rectrix indicates Yellowhammer;
• a small percentage of Pine Buntings lack dark shaft streaks on the undertail-coverts, which is rare or does not occur in Yellowhammer;
• the falling clear call of Pine Bunting is probably diagnostic; there are small differences in other calls as well that might be useful.
*Hellquist (2016) Identification of female Pine Bunting – new pieces to the puzzle. Dutch Birding 38: 129-146.
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