Once again wing entrapment has struck again. Every year (early in the season usually) I have to deal with martins that get stuck in SREH entrances. 2 ASY males, one stuck in the sreh and one within the nest. Unfortunately I was out all day visiting family, came home after dark and this AM this was what I found.
For those that don’t know, Wing Entrapment is when a purple martin becomes stuck in a SREH. It usually happens when 2 or more martins are fighting over a compartment (nest spot) of any gourd or house with SREH (Starling Resistant Entrance Hole) As one bird tries to leave the nest and is trying to fend off attacks from within the nest from a rival or occupant, the bird gets stuck in the entrance. Basically gets stuck when he turns as he is trying to exit. If not discovered fairly quickly the birds in the nest can die as can the stuck bird. I have wondered if vented rooms vs non vented rooms have a better survival time but this nest was fairly well vented. But still the blocking off of the entrance must have happened early in the AM and as I was out all day, there they sat and died. Those that have reported deaths from entrapment usually say that they discovered it either the same day or within a day or two of the event.
It is important to note that this Sunset Inn house did NOT have wing entrapment guards on the inside of the crescent entrances. Also there have been reports of wind entrapment on the large Trendsetter houses that DO HAVE wing entrapment guards. I am not sure if the problem is the thickness of the guard, as the Trendsetter entrapment guard is not the thickest I have seen There is no standard thickness for a guard also and it is hard to just say that thicker may be better, because we are not real sure if at some point, the thickness would hamper their entry and exit into the compartment or cause some kind of situation with young birds crowding at the entrance waiting to be fed.
You can read about wing entrapment in previous blog posts as well as on our parent website, www.PurpleMartins-R-Us.com. Is wing entrapment a reason to not use SREH? Absolutely not. Wing entrapment remains much less common than the threat of Starlings in an unprotected colony. Of course, you have to weigh the pros and cons in your colony along with your sites individual risk factors for both problems.