28 Oct 2002, 02:04, Joe Paulson (1:150/115), wrote to All:

Hi Joe.

......

 JP>   I started wondering if ,in these days of electronics,if it was
 JP> possible to make a bird box that would be selective .If a box
 JP> would only allow birds in with the color blue,bluebirds only 
 JP> could come in if the entrance hole was small.Bluejays would be too 
 JP> large.
 JP>   Similiarly,a barrier that would prevent brown birds from 
 JP> entering would keep out sparrows,and allow chickadees in.

 JP> A box could be powered with a small battery and photovoltaic cells 
 JP> on the side of the box.A color detector at the entrance would 
 JP> make choices.I'm assuming daytime conditions.
 JP> The only problem is HOW to activate a barrier for going IN and 
 JP> for going OUT.Maybe some kind of fiberoptic sensor.
 JP> And HOW to design a mechanical barrier that stops a bird.
.......

Wonder if it might be simpler to work on what different breeds of birds may
"see".  ??????

Illuminate the entrance with an led with an 'oversize' series resistor so
that it barely lights up, and use different colors on different birdhouses,
then observe the results.  I know LEDs come in IR, Red, Yellow, Green,
Blue, Orange, (White would seem to be useless).  Certain colors might have
the effect of attracting or repelling certain breeds. 

Just a thought...


     Good luck...  M.

--- Msged/386 TE 06 (pre)