Thoughts on what makes a new site attractive to purple martins
Every year at this time, wanna-be purple martin landlords have the same question. Even experienced Purple Martin landlords are not always absolute in their answer to this question as there are many factors to consider.
The question?
What is the best housing to attract Purple Martins?
Answers vary from :
Use what others in your area use, to definite opinions regarding gourds, or particular house designs. The ease of attracting martins for the first time is often related to the Martin population in that area of the Martin range. Many seemingly ideal sites go unoccupied leaving one to offer an assortment of housing styles in order to cover all the bases.
For me, before I developed ChirpyNest, I would have recommended natural gourds, to someone trying to attract martins for the first time. My colony of martins never preferred plastic gourds. In fact until I added tunnels I was regretting buying plastic gourds at all. Even now for a new landlord I recommend offering natural gourds along with ChirpyNest in order to attract that first pair. Once established though, ChirpyNest is far better and I would wean off natural gourds.
I built my colony on natural gourds, added a T-14 along with enlarged trio houses. After ten years I began to replace my natural gourds with plastic super gourds and Troyer horizontals. Lack of time to keep naturals in top shape and the time to initially prepare them is why converted to plastic.
Coinciding with my switch to plastic gourds, 2011-2015, my colony declined from 70 to 25 pair and low occupancy of the plastic gourds was disappointing . The addition of tunnels to the plastic gourds helped make them more attractive but as more and more conversions were needed ,such as vents, and vented lids in order to make these gourds livable, I developed the ChirpyNest as a better way to house my martins.
What makes a potential nest site stand out to purple martins? Is it the shape of the cavity?
The opening as seen from afar? Have we conditioned the martins to look for housing sitting atop a pole? Maybe passing martins see telephone poles as tree snags, their instinctual nesting place, and upon investigating these potential nest sites they stumble upon our house offerings, presented from their perspective in a similar way.
Given a choice, I feel martins prefer a bit of space between cavities, hence the current preference for gourds, especially when starting a colony. Considering the issue with porch in condominium style housing reassures this belief. Once a colony is established and the birds are secure that the site is a safe one, they will take up residence in housing with closer neighbors. I have experienced this at my own colony where the area wide Martin population is small. This also seems to hold true range wide as one thing Most landlords seem to agree on is to add gourds to traditional houses if you are trying to attract martins for the first time. This advice would seem to support the theory that the additional space between cavities makes the cavity and site more attractive. It could also support the theory that the birds are attracted to the gourd shape but when you ask the question Why? It forces you to think a bit further. I think gourds are attractive because a gourd hangs as an individual nesting cavity, with territorial space between the next cavity.
Once a nest site is productive , the martins remain loyal to that site and will return to nest year after year. From an initial colony, related birds will find nearby sites more easily but the first seed is that tough one to sprout, especially in low Martin population areas. Do martin fledglings imprint on housing type they are raised in? I have doubts, but I do think parents will return to the same type housing if they were successful in raising their young.
When I envisioned the ChirpyNest, I set out to develop housing that is better for purple martins and better for the Martin landlord. I think I have succeeded by overcoming the deficiencies of gourds, such as poor ventilation ,while enhancing the positive aspects of current Martin housing, retaining the the territorial space purple martins prefer.
The martins have filled the ChirpyNest cavities better than they ever used plastic gourds at my sites. Because of the superior cavity environment the ChirpyNest will be even more attractive than gourds to purple martins looking to establish new sites. ChirpyNest has become the preferred cavity at my established sites and my colony has rebounded.
I am looking forward to another Martin season, the fourth using the ChirpyNest. I hope to gather more information from other landlords on the success their birds have using the ChirpyNest. Time will tell just how much better the martins do while raising young in ChirpyNest houses. I am most excited to see how landlords incorporating ChirpyNest, do in their attempt to attract that first pair of martins.
As the calendar turns to February I am thinking of warmer days ahead and the return of my Purple Martins.
I welcome your thoughts or comments on this topic.