Hardware stores carry some good materials. Back in the fencing/roofing section, look for long corrugated vinyl panels that are used for roof-overs. I decided to go with these panels for my new pheasant pen. The 26" tall x 8' panels came in white only, and cost $13.65 each at Lowe's. 26" tallx12' long cost $20.48 and come in several colors. They won't allow airflow, but won't retain heat like metal. The price isn't bad, and they are readily available in case you need to replace one down the road. Hope this helps.
Sight Barrier Material for Peafowl Pens - Page 2
I have to have air flow. It's just to darn hot in this part of Texas. We've used some of the polycarbonate roofing in the light grey which is almost clear and green. Alternated the 2 colors to create shade but also light in the back shed area. They work great and are suppose to last about 15 years even in this blazing sun.
Sorry, I know I need to reply to some of the other ideas. Have read them. I can't believe something isn't manufactored for this purpose.
I know you said you can't use plywood, but if you don't mind wood as a material, you could try a "woven wood" fencing along the bottom. The sort that has 2 rows of vertical slats, one on either side of the center support, alternating so that there's no actual gaps straight through, but wind can pass through it. Kind of like this: http://www.obra.at/images/sichtschutz5_big.jpg
How to build them:
Alternately, and I don't know how expensive this would be, but there are companies like this that sell cloth privacy fencing- these guys even have a 'noise reduction' privacy fence... http://www.privacyfencesolutions.com/
There are also mesh screen tarps, which are breathable and since they are not natural fibers, won't rot or mold. http://tarpsurplus.com/privacy-fence-tarps.html
Need to look into these. Thanks.
Might be more than you want to spend but what about the 4x8 sheets of plastic lattic; It does last forever. I put it up on dog pen just to make it look nicer. It comes in different size holes. Don't know if that would be enough to detour them from seeing each other or not, but would let air through and not be as hot. It comes in white, tan, and green I think.
You could try shade cloth. The type they use over greenhouses and dog kennels. It could be cut to the height you need. Air will go through the cloth and it should also be dark enough to stop the fighting. It's a thicker material so should last quite a while. You can get it at Menards or any other place that sells tarps and such.
Has anyone thought of silt fence? You see it around construction areas where loose dirt can be blown during heavy winds,,I think it's an EPA requirement on new construction projects where topsoil is removed and not replaced for more than a week. It is about 24" tall and is black poly film,it's super heavy and sometimes landscapers have scrap rolls left over they will sell for practically nothing.
I agree with the silt fence idea, even if you can't find it used it is not expensive and I've seen it in use at a breeder's facilities.
Looks like Home Depot and Lowes has silt fence. I know they have shade cloth. I'll check them out. I'm thinking the shade clothe will let more air/breeze through. It was 106 today here in Hill Country of Texas about 30 miles north of San Antonio. I had fans, water misting and pans of water for the peafowl to stand in and they were still panting. Sure can cut off circulation between the pens. Thanks everyone.
Since this thread I hatched some swan eggs and now have 2 Black Australian Swans, Gracie and Gunther, 8 months old. Have been working on a habitat for them all summer and about finished. I'm thinking about putting shade cloth up around their Safe Pen where they'll stay nights. They tend to pace and want out through the wire unless they have a big kiddie pool to swim in. Don't think I'm going to supply them with swimming water in their night pen but they'll have a few swimming pools in their big day yard. They have been more work then peafowl could ever be but they are worth it. Love my Aussie Swans!! (-: