At my previous colony site in Tallahassee, Florida, gray rat snakes were plentiful and would have eaten many of the martins if I had not installed snake guards, including bird netting traps on the housing poles. This year at my new home in Louisiana I did not catch a single rat snake in my net traps. Whether rat snakes were either fewer in numbers this year or my colony was just lucky, I don?t know. The upcoming martin season in 2006 may have more snake issues. Everyone should place some kind of snake guards on their purple martin housing poles, particularly folks living in the Deep South. Rat snakes are common down here and predate many martin colonies each season.
Below are two photos of a large gray rat snake that was caught in a net trap composed of ? inch mesh squares. This snake was almost five feet in length and the ? inch mesh caught him/her in several locations. Large snakes with thicker girth are readily caught in the ? inch mesh. However, smaller diameter snakes may be able to weave through it and I now use a combination of ? and ? inch mesh squares. The ? inch mesh has caught both large and small diameter snakes, including some that were around two feet in length.
The netting works when the snake weaves through the mesh by deflating and then inflating its body, using strong muscular movements. Rat snakes have narrow heads which allows them to push through vegetation and enter rodent burrows. The snake reacts to the netting in the same way he/she would to some vegetation and starts to weave headfirst through the mesh. As the snake pushes through, his/her scales eventually get caught in the fine mesh through the body movements and he/she can?t back out or go forward. The more the snake tries to get out, the more he/she becomes entangled. Some large thick snakes will only get their heads and a few inches of their bodies through several mesh squares and then will be caught in that location. Other snakes may weave deeper inside the netting and be entangled in several body areas up to the mid-point of their length. A combination of ? and ? inch mesh squares will probably catch nearly all rat snakes that try to weave through the netting.
It is important to remove the snakes unharmed as soon as you discover them trapped in the netting. Unfortunately, snakes will easily die in these traps if left for several hours unattended or if exposed to direct sunlight. So far, I have not lost a single rat snake in my traps and was able to safely remove them unhurt. I grab the snake?s head and then gently cut the netting from its body until I can free the snake. After that, I take the snake about a mile from my home and release him/her in an area with thickets or other suitable ?snake habitat?. If the snake has been in the trap for a while, then he/she may be rather docile and not try to bite you. However, some large rat snakes can be more aggressive and can bite hard. Several have ?raked? their curved back teeth against my hands or arms and drawn some blood. These rat snakes had apparently been recently caught and were ?rather angry? at their predicament! But I usually manage to grab the snake and remove him/her without being bitten. If you have a snake phobia, then this makes the removal process almost impossible!
Steve
