[texbirds] Re: Today's field trip (with regards to Purple Martins)

  • From: Jake McCumber <jake_mccumber@xxxxxxxxx>
  • To: "texbirds@xxxxxxxxxxxxx" <texbirds@xxxxxxxxxxxxx>
  • Date: Sat, 7 Jul 2012 23:00:43 -0700 (PDT)

Hi Lori et al.,

I've been doing some sampling of the Highland Mall Purple Martin roost again 
this year.  They have been a bit tougher to survey this year due to weather and 
earlier initiation of dispersal.  However, based on the counts I've done so far 
I've calculated an average estimate right about 600,000 Purple Martins.  Radar 
suggests the samples have been representative of the roost though weather 
hasn't cooperated when I've tried sampling at sites around the dispersal ring 
other than my primary one.

They did start early this year, fitting with reports I heard of fairly early 
fledging.  It's hard to know if they are peaking, but my presumption is that 
the roost is about as big as it's going to get.  What I don't know and would 
really love to see studied is where birds are coming from to populate the 
roosts along the northern gulf coast.  Are there still birds en route from the 
north?  Are birds leaving for wintering roosts already and being supplemented 
by northern birds?  There are plenty more interesting questions about these 

Anyway, Travis Audubon Society will be hosting evening roost observations the 
next three Fridays and next three Saturdays from 8-9.  

Jake McCumber

Quoting Lori Markoff:
"Has anyone good at estimating bird numbers been there lately?  There were so
many I have to wonder if they are peaking early?"

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  • » [texbirds] Re: Today's field trip (with regards to Purple Martins) - Jake McCumber