Fast Food For Snakes- the Avian Nest Box


Humans delight in trying to improve the lives of our beloved birds, but sometimes this can go horribly wrong. A case in point is the nest box which is erected for hole nesting species such as bluebirds and tree swallows. The easiest way to erect a box is just to attach it to a post or tree. However this has a huge downside in that it provides no protection against climbing predators such as raccoons and snakes.

One result of my being lazy and not providing predator protection for a small number of our nest boxes was revealed recently when I suddenly noticed a snake head protruding from a nest box I had simply screwed to a post holding up my wood shed roof. A large black rat snake had climbed up or down the pole and crawled into the box. I believe that this brood of tree swallows had left already and were safe. However our other boxes still have young birds in them and would be at risk if not protected. Indeed the black rat snakes in our area seem to be almost entirely bird eaters and refuse to eat mice and rats in captivity.

I am a huge fan of reptiles and in fact previously taught a course in herpetology. Thus I certainly am happy to see snakes and believe in allowing nature to take its course. Snakes must eat and they just happen to be predators as are many humans. But it upsets my wife to see this happening on our land so I remove and transplant any snakes we find on our farm near the house. One solution is to place stove pipe baffles on all nest boxes which are erected on metal pipes. This will protect from all but aerial predators.

So I urge you to be responsible landlords of your nest boxes and protect them as well as possible from predation. I also urge you to resist irrational fears of snakes which may be rooted in religious myths and possibly also in the response of early humans to the unusual shape of snakes (which can be considered phallic symbols) and their unusual ability to shed their skin intact. Although we all have our irrational fears, they can be no ecological justification for selecting out certain groups of animals for persecution. Let us strive to live in harmony with all of nature and impact it as little as possible.

Bill Dunson

About Bill Dunson

Bill Dunson, born in rural Georgia, skipped 12th grade and went directly to Yale. Bill subsequent-ly received a PhD in Zoology from the University of Michigan, studying softshell turtles. Bill is Professor Emeritus of Pennsylvania State University thanks to a career spent entirely at that institution, teaching and doing research on the physio-logical ecology and ecotoxiciology of reptiles, amphibians and fish. Always curious about nature, Bill has dedicated his life to learning and sharing his knowledge with others. He has served on many advisory boards here in Southwest Florida to preserve the water that gives life to our region.

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