This morning I hear the bubble and squeak song of a male Brown-headed  
Cowbird and, as I’ve done before, find it perched on the street sign on the  corner 
of the front yard.  A  parabolic mirror is mounted atop the sign – put there 
by my neighbor so he can  see traffic coming when he pulls out of his garage 
drive.  For the first time I spend some time  looking at the cowbird and realize 
that it is interacting with its  reflection!  This mirror has  apparently 
become the focus of the bird’s territory. 
I get out the scope, setting up on the front porch and get a few  pictures.  
The bird leaves after ten  or more minutes but returns several times during 
the day, repeating rituals  of interaction and display each time. 
The bird will face the mirror usually very close – its bill almost  touching 
the reflection – then bow down with its bill pointed straight down –  
offering to be alopreened.  Several  times I see it fluff up its back feathers and 
coverts and nape.  Occasionally it flies atop the mirror,  bending down to look 
at its image then returning to stare and display,  occasionally pointing its 
bill up and uttering a high squeak.  After a few minutes it sits down atop  the 
sign, always facing the mirror.  None of its actions appear to be aggression 
unless the bill-up posture  and call is a sort of passive/aggressive move. 
As I hear the female’s rattle call about once a week, I presume that she  
returns to the male’s territory (or is it her territory?) whenever it is  time to 
begin egg-laying.  The  female can lay as many as 35 eggs in a season (50 
according to another source),  and will do one a day for a week or so and then 
rest for a few days and then  repeat.  [Skutch mentions someone who  called 
female cowbirds "passerine chickens."]  I’ve seen the  female skulking in the 
thick bushes around the house a number of times where the  catbirds prefer to nest 
(four pair in this one acre yard).  I read that catbirds are one of the  
species that will recognize and reject a cowbird egg, so her efforts (and his)  
may well be wasted. 
[The best source for information on the cowbirds that I have in my  library 
is Alexander Skutch’s book “Orioles, Blackbirds, & Their  Kin.”] 
What I find noteworthy is that this is the first year in my 21 years of  
birding this yard that cowbirds have been anything other than transient – also  
true of the nesting House Sparrows this year.  Something has changed ... but 
what?  There are fewer woods (i.e., more houses  and streets and malls) 
surrounding the general area.  Bushes and shrubs in the yards around me  are mature and 
thick, averaging at least 45 years old and many of the trees are  of the same 
age.  Maybe well-treed yards are the new  mixed deciduous woods.  Up until 
early this year we have always  had at least one, sometimes two cats which were 
house/outdoor cats ... but their  presence had never deterred the catbirds, 
cardinals, robins, Chipping Sparrows  and Carolina Wrens that have been regular 
breeders all along. 
Anyone want to help shed some  light? 
Lou
 
Louis Nielsen  
Reisterstown, MD