Sunday, September 22, 2013

overview of today, and possibly a good night to listen for migrants after dark


Lots of birds were reported in the area today, including around the metro area.  I just snuck over to LaSalle Park in Metairie and, in the difficult light around 6 pm, had 7 Northern Waterthrushes, 3 American Redstarts, and singles of Black-and-White, Hooded, and Magnolia Warblers.  Also a Pewee and two Ruby-throated Hummingbirds.

A couple of birders who went to Grand Isle reported lots of birds, with 23 species of warblers.  Among their counts were 67 Red-eyed Vireos, and 20+ each of Black and White, Magnolia, and Tennessee Warblers, and American Redstart and Northern Waterthrush (which led the warblers at 41).  They also reported 36 Pewees.

It is never possible to predict with certainty, but tonight seems a good setup to detect nocturnal migration. The vast majority of small land birds migrate at night. Low cloud cover with north winds are good conditions to listen for the flight notes of migrants passing overhead.   On the best nights, the calls may be audible at around one per second or better.  But even a night with just a few calls detected per minute can be fun. Thrushes often make up the bulk of call notes at night (this is something of a paradox, since we tend not to find so many "grounded" during the day, but call note frequencies can sometimes suggest large numbers overhead at night).

The most common are usually the heep of the Swainson's Thrush, and the husky veer of the Wood Thrush. There are recordings available that sort out the nocturnal flight calls of different species, and some birders really get into identifying them.

One problem in the city is ambient noise; I find it helps to cup my hands behind my ears to amplify sounds.

Start listening about a half hour after dark, and on into the night.

Good birding!

Peter

2 comments:

  1. At 9:30 pm, call notes are audible at a good rate in Old Jefferson. I counted 25 in 2:00 minutes, or one per ~5 seconds. Everything loud enough to resolve appeared to be a thrush; most seemed to be Swainson's.

    At 9:10, a similar (perhaps greater) rate was audible near Bonnabel High School three miles to the north of Old Jefferson.

    Peter

    ReplyDelete
  2. At 9:30 pm, call notes are audible at a good rate in Old Jefferson. I counted 25 in 2:00 minutes, or one per ~5 seconds. Everything loud enough to resolve appeared to be a thrush; most seemed to be Swainson's.

    At 9:10, a similar (perhaps greater) rate was audible near Bonnabel High School three miles to the north of Old Jefferson.

    Peter

    ReplyDelete