I use Troyer Horizontal Gourds, Troyer Verticals, Excluders and Super Gourds in my purple martin colony. These are high quality gourds made from opaque (non-translucent) plastic and well-liked by martins in my colony. I bought my first Super Gourds about 15 years ago and these gourds are still almost like new, particularly when I clean the outsides. My other brands of plastic gourds are durable too and show almost no “wear and tear”. The plastic has withstood the relentless “attack” of UV rays from the sun down here in the Deep South and I believe my gourds will be still around when I am long gone!
All these gourds have access ports so that the landlord can monitor the insides and clean out old nests. You simply unscrew the cap and check the inside of the gourd. There are two types of caps available for the commercial plastic gourds mentioned above. One is the older style which I have used for many years and the other is a newer heavy-duty cap developed by Andy Troyer for his gourd brands. For the upcoming 2014 martin season I have now replaced ALL my old caps with the newer ones; I started doing this in 2012 when these new caps became available.
There are significant differences between the older cap and the newer one. First, this new cap is thicker, made from heavy polyethylene for maximum UV protection and has a “built-in” liner that blocks sunlight from entering. The original cap is thinner and has a painted paper like liner that is glued in. The original liner is opaque but is not thick and can eventually pop out as the paper degrades or the glue gradually loses its grip. If the liner comes out, the old cap plastic is translucent and allows sunlight to come through and into the gourd nest cavity. Also the old cap’s thinner plastic is more vulnerable to sun damage particularly the rim and can become brittle and eventually start crumbling/cracking. As the plastic deteriorates from UV damage, the plastic may become more easily cracked/punctured by hail.
Second, the outer rim of the new cap has multiple ridges spaced about one inch apart which makes it easy to grasp and twist on and off. The original cap rim does not have these ridges and is not as thick. However, the older cap is still easy to twist on and off.
Third, the inner threads of the new cap are thicker and seem to grip and hold better when twisted on the gourd. The original cap threads are thinner and I have had problems with the caps popping off some of my older Troyer Horizontal Gourds. I never had any issues with caps popping off involving Troyer Verticals, Excluders or Super Gourds. Since I have used these heavy-duty caps, none have popped off.
Fourth, the new cap fits the Troyer Vertical and Horizontal Gourd, the Excluder Gourd and the Super Gourd. Some landlords have told me that these caps haven’t fit some of their Super Gourds. I tried the caps on some of my Super Gourds and they fit nicely. But there could be some of my Super Gourds that will not work with the heavy-duty cap. The Super Gourd now has its own heavy-duty cap and I’m using them on all my Super Gourds. This Super Gourd cap is very similar to the Troyer heavy-duty cap in quality and design.
And lastly, there is some logo on front of the new cap that I like. It says, “Thank You For Caring For The Purple Martins” “Made In USA”. There are also four purple martins “engraved” on top of the cap. I particularly like the “Made In USA” logo! All of the Troyer, Excluder and Super Gourds are made in America. So when you buy these access caps and gourds you are not only getting a high quality product but helping American workers, too.
The older style access cap will last longer if you store them out of the sun/weather during the off season. You can also paint the outside of the cap white to help minimize sun damage and even the inside if the paper liner deteriorates. However, I prefer to have an access cap like the heavy-duty brand which will last longer with limited maintenance.
If your older access caps are showing signs sun damage or the paper liner is deteriorating, you might want to consider replacing them with the newer heavy-duty cap. The heavy-duty cap should last longer and require less maintenance issues. You can order these heavy-duty caps through the PMCA’s online catalog and I have done that on several occasions. Here is the link to these caps:
http://shop.purplemartin.org/Heavy_Duty ... tails.aspx
This photo shows five plastic gourds with the heavy-duty access caps in place: Troyer Horizontal with cling plate, Troyer Horizontal with tunnel/porch, Troyer Vertical with tunnel/porch, Excluder Gourd and Super Gourd. I now have 300 plastic gourds in my 2014 martin colony and all have the heavy-duty access caps.
This photo shows a comparison between an older access cap and the newer heavy-duty one.
Here’s another photo showing a comparison between an older access cap and the newer heavy-duty one. You can see where the paper liner in the older cap is coming loose.
Steve