We were very fortunate two years ago when we put up a cheap, farm-store Purple Martin house and within days had a small colony forming. I think we had six pairs that fledged chicks that first year. The photos below are from last year – April, May and July.
Last year, we added a gourd tower (manufactured plastic, individual houses hung on a tower.)
Sure enough, some of the Purple Martins chose the gourds over the standard square house and the colony of these cheerful, vocal birds increased in numbers.
While they showed they were able to meet the needs of the Purple Martins, I wasn’t terribly pleased with the gourds I acquired. They were not manufactured very well. They came in two pieces with one screw. The two sides were supposed to snap together and the single screw (at the very top) was supposed to hold the unit together. Just manipulating the two plastic pieces to fit into the groove was challenging. The bottom design didn’t hold the sides together as it was specified to do. In the end I ended up placing a long strip of tape down each side of each gourd because I had little faith they would not pop open at some point and little, baby birds would tumble to the ground. I hoped the tape would last the summer breeding season. Fortunately, it did.
After the Purple Martins had fledged their new broods and flown south for the winter, in late autumn we had a heavy wind and a few of the gourds fell to the ground. The tower I purchased had metal clips to secure each gourd and apparently they failed. I realized that if we wanted to continue to provide summer breeding housing to these lovely birds, we would need to make some improvements.
There’s a saying that necessity is the mother of invention. We train dogs and we have a small, therapy pool. Those are unrelated ventures! However, they both require the use of bleach. One day, I noticed a large stash of empty bleach bottles Robert had set aside. It brought forth an idea. Those bleach bottles (BB) looked similar in shape and size of the plastic Purple Martin gourds. I wondered if we could repurpose the empty bottles into the 2021 Purple Martin colony upgrade.
For inspiration, I went to the PurpleMartin.org website to see what sort of products they offered. Of course, they have many versions of manufactured “gourds” as well as the actual, natural gourd options. Some of the plastic options are incredibly fancy – and of course, expensive (we are talking hundreds of dollars!)
The price point for an eight gourd until was hundreds of dollars over what I could spend. However, I did purchase three fairly inexpensive products which I thought could be added to our BB experiment. Then, I waited for them to arrive while I contemplated all of the pros and cons of adding a BB tower to our farm-store basic housing unit and the gourd tower. Finally, I discussed the project with Robert since he was likely to be the man in charge of building the hanging structure and assisting on the individual units, too.
Today I decided to create a prototype in order to have the opportunity to touch and manipulate the new apartments. It was the beginning of this experiment and I was quite excited to get started. Purple Martins send a scout in advance of the rest of the breeding age adults. That bird’s arrival is tracked by the experts. We live in a zone of “March 15” as the time we should expect a scout to arrive. That is when we should have our housing available so that the scout can direct the later arriving colony members to choose our location! I’m feeling a time crunch coming on!
MY BB UNIT PROTOTYPE PROCESS
First, I allowed the BB to hang off my finger to see how it settled. It hung fairly perpendicular to the ground with only a minimal tilt. I decided to put the hole on the downward tilt side (opposite of the handle.) I figured the birds could make that approach and positioning the hole on the “underside” would prevent the elements like rain or wind from entering the interior.
Next, I used one of the prefab gourds I had purchased last year to determine where to place the hole – measuring from the bottom of the bottle. I am aware that the BB have more space above the hole than the gourds provide. I am not certain how much that might affect the birds from finding them suitable. But, I figured that the space from the hole down to the bottom is more critical than the space that is above the hole. That is where the nest will be built and the chicks will be fed. I’m no expert. It’s just an educated guess.
I used a template that I purchased from the PurpleMartin.org site to draw the outline of the hole. This half moon design is referred to as a “Starling Resistant Entrance.” It’s not exactly the same shape as the hole in the gourds we have, but it’s from the Purple Martin experts. So, I chose to use this template rather than to sketch the shape from the plastic gourds. We didn’t have an issue with Starlings in the last two years, so I’m hoping this will still be sufficient to prevent them from attempting to occupying a BB housing unit.
I used a dremmel tool to cut the hole. It was a bit of a fiasco. I couldn’t move along quickly enough for the bit to refrain from zipping a slice in any direction it choose to take my hand. I suspect controlling the bit is just one of those skills one needs to practice. I attempted rectifying the imperfections using an exacto blade and realized that’s a fairly dangerous tool to use on a slippery, curved surface that isn’t secured in one place.
Don’t freak out. The image below isn’t testament to my inability to even get close to the pre-drawn line!!!! I actually realized I had made a measurement error the first time I drew where the opening should be. Then, I drew a new hole and cut along that line.
Another of the goodies I acquired from the PurpleMartin.org site was a preformed, metal “porch.” While the gourds we used last year do not have any sort of “perch” outside the hole, there’s actually a reason for that omission. House Sparrows are said to prefer houses with a front door perch. Leaving it off is considered a method of discouraging HS from moving in. When the Purple Martin chicks fledged from our Red house (which did have some issues with House Sparrow invasion), we were able to see them sitting on their little porches before flying off. That option was lost to the gourd fledged chicks. So, I purchased a few of the metal porches. It’s part of the experiment.
Curiously, when I tried to install the metal porch though the hole I created using the half-moon template, the porch didn’t fit. I had to trim the hole a bit larger.
When I compared the somewhat larger hole in the BB unit to the original gourd, it was clear that the gourd opening was significantly smaller than my premier BB unit opening. I worried about a Starling take over. Perhaps, that’s merely because this recent deep freeze has brought many Starlings to my feeding station on my back patio, and at times it’s a bit like watching the Alfred Hitchcock movie, “The Birds” as I look outside.
Note that the plastic gourd opening is quite a bit smaller than the template opening.
In a second bleach bottle, I cut a hole using the Starling resistant template. When I tried to fit the metal porch through the hole, again it didn’t fit. This time, rather than cutting the hole in the BB larger, I chose to trim the metal porch. I left one side (the exterior porch) the original size. I trimmed the side which would become the interior platform just a bit smaller. That way I didn’t have to enlarge the hole and make it even larger than the original gourd entry port. In the following photo, the pencil is pointing to the side that I trimmed versus the unchanged porch on the right.
The final product that I purchased as a means of exploring options to make our BB units the best they can be, was a “gourd canopy.” Some of the fancy plastic gourds have an “awning” of sorts molded into their design. It is intended to reduce the effects of wind and rain from entering the nest unit. This little piece of shaped and curved metal is offered to people who prefer using the natural gourds, but with the canopy enhancement.
The written instructions suggest that one use a bead of silicone calking to attach it to the gourd. I just used a couple of pieces of tape to see how they might fit the BB units – we can attach it permanently later. The first photo below shows it attached to the BB quite high versus the opening (which is above a horizontal groove line that is designed into the bleach bottle.) The second photo shows the two prototype BB units with the canopy attached closer to the opening.
With two prototypes completed for examination and contemplation, I invited Robert to come add his two cents. We had a good discussion about the entry holes, the canopy placement and the design of a porch. I only purchased a couple of the professionally manufactured items, and we discussed whether to purchase more of the same, or whether to create our own design.
We also discussed how many BB units we should implement into the experiment (Robert said 50!) And we talked about the support poles and placement of the units on the poles. I envision hanging the BB units on a horizontal pole at the same height as the current gourd tower and another pole for a second story of the BB units a bit higher or lower than the first. I don’t think it needs to be as “three dimensional” as the gourd tower. After all, many species that nest in colonies, do so on the side of a hill or mountain where the nesting units are positioned in a far more column/row orientation than a circular format. Robert may have another strategy. We’ll see what we come up with when we are ready to hang the BB units for occupancy. It brings a smile to my face to think about that day.
In the meantime, we must continue to do “real” work and tend to many other projects. But, it didn’t take long to create one BB unit, so once we decide on the best design I can create a unit or two every day just as a way to put my mind and hands to work on something a bit creative and fun!
I will update on this project as we move forward! Comments are always welcome.