Comparison of Azorean atlantis with Other Forms

Table 1 shows how features of Azorean atlantis compare to those of the other two proposed Atlantic forms -- Iberian atlantis and Southern atlantis. It will be noted that only two features of Azorean atlantis are tentatively identified as being distinctive:

Three features are closer to Southern atlantis:

One feature does not provide any distinction:

Four features are too poorly known to provide any information:

One feature possibly favours Iberian:

Four features are closer to Iberian:

On this analysis it is not possible to classify Azorean atlantis as either Iberian or Southern atlantis. It does have a small number of characteristic features so should perhaps be treated as a form in its own right: Azorean atlantis.

Obviously further information is required for a more definite view of the atlantis of the Azores.

  

 

Form of atlantis to which Azorean atlantis is closer

Distinguishing feature of Azorean atlantis

Comments

References

Adults

 

 

 

 

Mantle shade/colour

Southern

 

 

Mantle shades

Biometrics

Southern/Iberian

 

 

Biometrics

Wing tip P10/P9

Southern

Smaller mirror P10, more often no mirror P9 (only 13% with mirror here, Teyssèdre, 1983); one study (per Dubois, 2001) reports only 2% have mirror on P9 compared to 10% in Madeira

 

Wing Tips ; Dubois (2001)

Wing tip P6-P8

Southern

 

atlantis has 60% more black on wingtip than smithsonianus, compared to 40% for michahellis

Wilds & Czaplak (1994)

Wing tip P5

??

 

 

 

Wing tip P4

??

 

 

 

Calls

??

 

 

 

Head streaking

Iberian

Possibly in fourth-winters mainly, extensive heavy streaking on entire head and upper neck sometimes extending to lower neck; further work needed to see how many adults have strongly streaked heads

 

Dubois (2001); Wilds & Czaplak (1994); Dubois

Timing of head streaking

??

 

 

 

Timing of primary moult

Iberian?

 

Very slightly later than Southern -- no more than 2 weeks (one feather). Timing of Iberian atlantis moult poorly known.

 

Timing of breeding

Iberian

 

 

Bannerman & Bannerman (1966); Bannerman Azores

Genetics

Iberian

 

Included in northern atlantis (with Iberian forms)

Liebers, Helbig, and de Knijff (2001); Genetics

2nd and 3rd years

 

 

 

 

Head streaking

Iberian

Extensive heavy streaking on entire head and upper neck sometimes extending to lower neck

 

Dubois (2001); Dubois

1st years

 

 

 

 

Head streaking and general duskiness

Iberian

 

 

Dubois (2001); Dubois

Many tertials have fine pale fringes or pale indentations or notches.

Iberian

 

 

Dubois (2001); Dubois

Views of Earlier authorities

 

 

 

 

Dwight

Southern

 

 

Dwight

Stegmann

Southern/Iberian

 

 

Stegmann

Bannerman

Southern/Iberian

 

 

Bannerman

Table 1: Comparison of Azorean atlantis with other forms of atlantis

 

© Copyright Nick Rossiter 2003

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