The Otway Forester Strepera graculina ashbyi: A neglected and misunderstood subspecies of the Pied Currawong from southern Victoria
Peter Menkhorst, Craig Morley
pp. 37-46
Abstract
The most southerly of the six described subspecies of the Pied Currawong, Strepera graculina ashbyi, is perhaps the least known and most controversial. Because it has reduced areas of white at the bases of the primaries and at the bases of the rectrices, its appearance is superficially similar to the Grey Currawong S. versicolor, and this has caused confusion from the time of its first description to the present day. Subspecies ashbyi is considered to be extinct by some authorities, yet our observations indicate that birds showing the phenotypic characteristics of ashbyi are common breeding residents in the Otway Ranges of southern Victoria and in the regional city of Geelong and surrounding areas. Here we review the taxonomic history, morphological characteristics and current status of S. g. ashbyi. We identify errors of citation and misinterpretation of the literature which, combined with a lack of ground-truthing, have resulted in the classification of a seemingly common taxon as Extinct. We then present a re-assessment of the distribution and biogeography of S. g. ashbyi and discuss the suitability of the type specimen. The true taxonomic status of S. g. ashbyi can probably only be determined by studies of rates of genetic introgression amongst Pied Currawong populations across western Victoria, but in the meantime its conservation status should be revised to Least Concern.
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