@Elspeth Dinsmore did research on this last summer!
		
 
		
	 
That's sweet of you to tag me, 
@tlcmurphy!
Yes, I made a 
thread last summer about trying to cut down on the heat in our aviary!
We ended up using 
privacy screen fencing over our chicken aviary.
Ms. WyorpRock 
suggested it to us, and it was a massive help! We had just hit a really hot week that year, and she helped us exactly when we needed it! I am so thankful!
We had quickly put up a blue and brown tarp for a couple days to try and protect the chickens from the suddenly hot week we experienced. It cut down on the heat, but was such a dark color that it got so hot it warped our PVC pipe frame for the netting over our aviary!
The privacy screen fencing was a beige colored screen that deflected a lot of the heat and sun, but allowed some wind and light through.
It lowered the 
ground temperature by about 45°-55° in the aviary -- going from 145°F - 90°F and 99°F.
It actually became quite pleasant to sit out there under the privacy screen with the chickens.
I also liked that the privacy screen fencing allowed wind through it, whereas the tarp did not. It put less strain on the structure that supported the netting and improved air flow -- which also made it feel cooler that we could feel the wind without the burning sun on us.
I hope this helps! I attached some links to different posts in my thread for more information. I hope you have a nice day!
-- Elsie
Soli Deo Gloria