27 Oct 2009

Skylark migration.

A beautiful clear moonlit night last night and I stood outside about 10.30 listening to Redwings calling as they flew overhead. Next thing I knew I was listening to a Skylark! At night? I'd always thought they were diurnal migrants. A quick internet search turned this up:

Night-migrating skylarks (Alauda arvensis) were captured during four successive autumns in France. The study aimed at detecting a possible influence of the lunar cycle on the nocturnal migration of this species. Though nocturnal postnuptial migration of the skylarks can occur during every phase of the moon, main nocturnal movements occurred when the moon was in its waxing gibbous phase. This phase gives the best conditions for migration because from the very beginning of night, it provides the necessary horizon for individuals to navigate and its light allows the use of topographic cues. In addition it allows the species to benefit from optimal conditions of illumination for almost a week.

Checked phase of moon at moment and its waxing gibbous! Just goes to show you're never to late to learn something new!

Just sortedsome photographs out and found this one of the Eastern-crowned Warbler. Unbelievably the golf buggy made it all the way from St Mary's. No wonder it took them two days!

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