We are purple martin colony managers for several years now. This year we had 18 breeding pair and fledged 71 birds. I need to add space if we are to have a larger colony. I am ordering PMCA Excluder Gourds with all accessories.
Question: which type entrances should I order, crescent or modified? I have ruled out the Excluder entrances. I currently have all crescent entrances on my apartments/gourds. They have worked well in that no starlings have entered that I have seen. We do have many starlings around that come and check out the gourds and nest boxes on a daily basis. I am unfamiliar with the modified excluder entrance. What are the pros and cons? Which do you recommend?
Dan in Fredericksburg, TX