Gulf Crossings

The BigSit!

This past Sunday, the opening day of the Great Texas Birding Classic featured the BigSit! competition.  A team selects a prime spot, and reports all birds seen from within a 17 foot circle in 24 hours. Competitors are allowed to come and go, but cannot count any birds while not in the circle.  Our GCBO team utilizes a spot along a levee road at San Bernard National Wildlife Refuge, due south of Houston on the coast.  The refuge provided us a marsh buggy to sit on (about six feet high), which helped see stuff at a distance.  The levee separates a brackish marsh from a small woodlot.  Open water can be seen a ways out with a scope.

Our team totaled 103 species.  I haven't seen the other results yet, but I think the teams from south Texas did better.  We missed a lot of expected things, and had very few shorebirds and very few migrant passerines.  Since a north wind had been blowing since Saturday morning, we suspect that most of the migrants left the night before, although spots east of us like High Island reported tons of birds on the coast.  Most of the Friday night arrivals apparently were directed slightly eastward, as the wind shifted from the south, then the west, and then the north that night.

Best birds?  A Golden-fronted Woodpecker was very unexpected - only the second record for the upper Texas coast.  Raptors were scarce - Caracara, Broad-winged, Red-tailed, and Swainson's.  There were thousands of soaring Anhingas.  Lots of snakes and alligators.  Not much else of note.  It was a beautiful day, and I have the sunburn to prove it.

Bill

Photo by Greg Lavaty

It's spring, so let's gather 'round the radar

Migration is heating up on the Upper Texas Coast, so now the fun begins watching radar and mulling over bird movements, which we do a lot here.  I'm going to post a couple of radar images from today as an intro - if you've never looked at birds on radar, I suspect you'll find this interesting.  I won't go into the details, which are much too involved for a blog, but I'll try to make a few comments about each image.  Note that these images are in "clear air" mode instead of "percipitation mode", so the objects shown have nothing to do with weather.  Please email me if you have any questions. I may post some more radar images and explanations later if folks find this interesting...

This is a "velocity" snapshot taken at 9:17 am local time this morning. The radar station is in the middle of the circle. The blues and greens are "objects" moving toward the station.  The reds, oranges, and yellows are objects moving away from the station.  The speed in knots is given in the legend on the right.  Note the Max Towards and the Max Away numbers, which indicate that the darkest colors may be greater than the max speed on the legend.  It is often difficult to distinguish birds from other objects, like insects and dust particles, especially if the other objects are being carried along by a strong wind.  In this case, however, the movement is from the gulf and toward the north.  Insects and dust would not occur in this pattern offshore, so these objects are probably birds.  Also, with south winds, this time of the morning would roughly coincide with the arrival of trans-Gulf migrants.

The following image is from the same station at 3:52 pm local time.  Most migrants have probably completed their trans-Gulf flight by now, so the pattern is much less exciting.