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| Domain |
Eukarya |
| Kingdom |
Animalia |
| Phylum |
Chordata |
| Sub-Phylum |
Vertebrata |
| Class |
Aves |
| Order |
Charadriiformes |
| Family |
Laridae |
| Genus |
Larus |
| Species |
spp.? (hybrid) |
| Common Name: |
Western Gull-type hybrid ? |
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| On October 27, 2007, we received from PB these pictures of an unidentified gull which had just been photographed using the remote camera 5 at Race Rocks. |
| David Allinson has helped us with the identification:" In short, the bird is not identifiable to species...most likely a hybrid gull also with partial hypermelanism (high melanism - darker than normal plumage and/or an example of some other complex colour abnormality which has caused its legs and bill to be darker (carotenism) -- caused by either genetic defect, environmental factors, and/or stress during development or moult). This bird is most likely a Glaucous-winged with Western Gull genes (or a Western Gull with Glaucous-winged genes!). However, the head seems proportionately small which suggests possibility of some other lineage (Thayer's or perhaps Herring). |
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| "Color Abnormalities in Birds: A Proposed Nomenclature for Birders" in "Birding" by Jeff N. Davis, Volume 39, Number 5, September/October 2007
Hybrid gulls are complex and often difficult to classify -- the existing nomenclature on classifying abnormally plumaged birds is fraught with error and misinformation (e.g. albino, leucistic, etc.). The article is a fascinating read (in fact most of the issue is devoted to abnormally coloured birds and also includes an article on bill deformities).
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| This file is provided as part of a collaborative effort by volunteer observers and students and faculty of Lester B. Pearson College |
Date:
Oct 2007 |
Pam Birley/David Allinson |
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