Wednesday, May 12, 2010

Update 5/12, next wave May 14?

Wednesday May 12: We've reached that point in the spring when some migrants are going to push northward even if conditions for migrating are not favorable. That's the only explanation I can see for the fact that a number of new birds showed up today. Tuesday night there were heavy rains and cool temperatures, and only a brief period during the night when winds were southerly, but today it was obvious that many thrushes had come in overnight. In the woods at Ottawa NWR and Magee Marsh, all five brown thrushes were seen, with numbers of Veery and Swainson's Thrush especially noticeable. White-crowned Sparrows and Rose-breasted Grosbeaks also appeared to have increased in numbers. Once again, the numbers of individual warblers were only moderate, but the variety of warbler species was excellent.

As of late afternoon Wednesday, winds are from the northeast, it's raining to the south of us, and rain is very likely tonight and tomorrow. I don't expect that many migrants are going to come in tonight. On Thursday rain is likely for much of the day, especially late morning and afternoon, and the forecast calls for possibly severe storms in late afternoon and early evening. So the migrants that were around today are likely to still be here tomorrow, but if you're pursuing them, be prepared to dodge rain showers.

On Thursday evening, even though scattered showers will continue, temperatures will be warmer and winds are predicted to be out of the south for most of the night. Also, it appears that there won't be a lot of rain to the south of us, so migrants that have been dammed up to the south will probably be moving this direction. It's too early to say for sure, but this could be a setup for a big arrival of migrants on Friday, May 14. It will depend on exactly where the rain showers are located late at night on Thursday, but if we get lucky, we could have a major influx of the second wave of warblers and other neotropical migrants on Friday. Keep your fingers crossed!


Joseph W. Brown said...


I'm not sure where to post rare Magee Marsh bird finds so I thought I would tell you about it.

Today (12 May) my birding companion George Kulesza and I found a very cooperative Bicknell's Thrush! We walked with it from sign posts #21 through to #24. It hopped nonchalantly along the shore, stopping several times so that we had great looks at < 6 feet. It had a stubby bill with yellow on the lower mandible, slightly contrasting tail (rufous), brownish flanks, no buff on the face and a partial eye-ring. Unfortunately we didn't have a camera to document the bird. However, if the above is not enough, it was singing! Open-and-shut. People around us fought over whether it was a Swainson's Thrush (with an inexplicable absence of buff on the face, no complete eye-ring, and an overall browner colour) versus a Hermit Thrush (with the palest red tail ever, and inexplicable absence of a complete white eye-ring). However, I think this is because Bicknell's is simply not on anyones radar (it certainly was not on ours to begin with). I wonder, has Bicknell's Thrush ever been reported before (it is not on the check-list)?

I am a graduate student in ornithology at the University of Michigan Museum of Zoology if you want a follow-up interrogation the next time you visit.


Anonymous said...

Whether there going to be still big warbler population on Sunday, MAy 16? or it will all over on May 14?

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