Colyton Wildlife: Spotted Redshank and more juv Yellow-legged Gulls

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Monthly walk at Vermont

Hermanus Bird Club

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John and Sheelagh Bowman will lead our August walk along the Vermont Coastal path on Thursday 2 August.  Participants are asked to meet at the parking lot adjacent to the Jan Rabie Tidal Pool at 8:00 am.  After the coastal walk there will be a visit to the Vermont Pan, which, once again, has water in it, so there should be some good birds.  See previous notice for directions.

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Probing the Puzzling Plumage Patterns of White Wagtails

Avian Hybrids

How can we explain plumage patterns in white wagtails subspecies?

Wagtail taxonomy is a mess. Numerous subspecies have been described based on morphological differences, but they are not supported by genetic data. A recent study in Journal of Evolutionary Biology took another look at several subspecies of the White Wagtail (Motacilla alba). Could they explain the mismatch between plumage and genetics?

Six Subspecies

Georgy Semenov and his colleagues sampled six of the nine recognized subspecies – alba, personata, baicalensis, ocularis, lugens and leucopsis – and sequenced 17 microsatellites. In line with previous studies, the genetic analyses revealed little population structure and weak divergence among the subspecies.

MotacillaAlbaDistribution.svg Distribution of White Wagtail (Motacilla alba) subspecies (from http://www.wikiwand.com/en/White_wagtail)

Puzzling Plumage Patterns

How can ornithologists explain this peculiar pattern of clear morphological differences without genetic differentiation? Recent genomic studies have shown that a small fraction of the genome…

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Are Wagtail subspecies supported by genetic data?

Avian Hybrids

A phylogenetic perspective on the relationships between Wagtail species and subspecies.

Ornithologists love to delineate subspecies. One differently colored feather can already trigger a response in the most extreme splitters. But are subspecific divisions always supported by genetic data? Rebecca Harris and her colleagues test this idea for a bird group that has its fair share of subspecies: the Wagtails (genus Motacilla). The paper was published in Molecular Phylogenetics and Evolution.

Some Subspecies

There are 12 species of Wagtails, distributed across the Old World. Two species complexes have fallen prey to subspecific splitters: the Western Yellow Wagtail (M. flava) consists of 13 subspecies, while the White Wagtail (M. alba) “only” comprises 9 subspecies. Some time ago I wrote about hybridization between two White Wagtail subspecies (alba and personata, read all about it here).

wagtails.png An overview of the subspecies in White Wagtail (left) and Yellow…

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Watch Your Head: Why White Wagtails Won’t Mix

Avian Hybrids

Hybridizing White Wagtail subspecies are separated by head plumage.

The White Wagtail (Motacilla alba) is one of my favorite bird species to observe. They frantically hop around the lawn occasionally wagging their long tail up and down. This small black-and-white passerine has a wide distribution across Eurasia and is divided into several subspecies. Some subspecies interbreed in narrow contact zones. A recent study in Molecular Ecology focused on a hybrid zone between two subspecies: alba and personata.

MotacillaAlbaDistribution.svg Distribution of White Wagtail (Motacilla alba) subspecies (from http://www.wikiwand.com/en/White_wagtail)

Sampling across Siberia

Georgy Semenov and colleagues collected samples across a 3000 kilometer long transect which ran from the Altai Mountains in Western Siberia (home of the alba) to Kazakhstan and Uzbekistan (where personata resides). They compared the distribution of several morphological and genetic traits along this transect. Genetically, the center of the hybrid zone was located in…

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