Predator Guards: A Story of Love and Betrayal

Per the PMCA, pole-mounted predator guards are an important part of being a conscientious and successful landlord, yet at the beginning of each Purple Martin season, as sure as the sun rises in the East and sets in the West, the inevitable debates regarding whether landlords should use predator guards or not begin on the multiple online forums. Yet, I have never met a purple martin landlord that wanted to set up purple martin housing so they could offer 'free food' to a raccoon or a snake.

Screenshot taken from video by Dan Pancamo (Full video linked below). The bulge in the snake's head is from the first 8-day old nestling he just consumed.

So many Purple Martins are lost each year to snake and raccoon attacks. It makes me sad every season to read about the losses - sad for the landlords who worked so hard to attract them, sad for the purple martins who died needlessly, and even more sad for the loss of what could have been a productive site contributing to the overall population and well-being of the species. We need MORE purple landlords hosting these magnificent birds - but not just throwing up a pole and a house / gourds and ignoring it, because, that's where the predators will take advantage.  What we need are MORE purple landlords that know how to make their sites safe AND productive - the very pleasant side effect of that is the landlord has an even more enjoyable season.

After all, who wants to pull a snake out of their purple martin housing, or clean up the blood & mess after a raccoon attack? That's not 'enjoyable' to me. Who wants the stress of not knowing whether the surviving martins will return in the next season?

A landlord removed the predator guards for one night and found this snake in the cavity the next morning - full of 3 nestlings.

Many experienced landlords are well aware that after a predator attack, the surviving martins may never return - in fact, many sites remain empty for years afterward. People don't go out and buy chickens & ducks and then not protect them from the resident coyotes, raccoons & owls, so why are our purple martins - a resource that is so much more precious - treated as expendable?

A fourth nestling was found on the porch and had been squeezed to death by the same snake in the picture above.

The impact of a predator attack is well documented by the PMCA and by landlords who have experienced the regrettable losses firsthand - they will be the first people to tell you - "Don't let it happen to you".  Check out the link below to see what is the number ONE reason for why people lose their martins.

See the PMCA page: Twelve Reasons Why People Lose Their Purple Martins

By the time the martins get here, they have already had to deal with a multitude of obstacles and aerial predators. The PMCA estimates 50-60% of purple martins are lost during migration both to and from Brazil.  With such challenges and losses already, it becomes even more critical to protect them when they get here. I am a firm believer that we should NOT create a free 'all-you-can-eat buffet' for any predator by giving them free reign and unhindered access to our nesting sites.

The Basics- Recommended Predator Guards (from the PMCA): 

Pole Guards—Also called predator baffles, pole guards are cylindrical or conical in shape and help prevent raccoons or snakes from climbing up the pole.  No matter if your pole is 12 or 20 ft tall, round or square, metal or wood, it can easily be climbed by snakes or raccoons.  Pole guards are commercially available (PMCA recommends a quick release pole guard for ease of use) or you can make your own. Per the PMCA, they should be installed at least 4 ft above the ground (higher if possible), 8 inches in diameter, and 2 ft long.

Netting—For those in areas with large snakes 1/2 - 3/4" bird netting can be used as a secondary line of defense.  Netting should be placed above the predator baffle in puffy layers, ensuring there is no space for the snake to climb between the netting and pole, or over the netting. 

Electric Fence Guards -  If you have an electrical outlet nearby, or can connect to a fence charger, this is a great way to protect your poles from any climbing critters. The only drawback to this method is, unless you have your fencing also plugged into a backup power source, then a power outage would leave your poles open to a predator attack. Even a fence charger can fail though, so backup guards are still needed, in form of baffle and netting.

Predator Baffle w/ Netting - Materials & Mounting:

The combination of a cylinder / pole guard with the netting mounted above the guard will predator-proof your poles and protect your nesting martins.
You can purchase a 'quick release' predator baffle here: https://www.purplemartin.org/shop/

...or you can make your own.  Here's a link on how to make your own predator baffle / cylinder guard: https://www.purplemartin.org/uploads/media/8-2-predatorbaffles-496.pdf
**Note: A good coat of Carnuba car wax helps prevent your metal baffle from weathering and helps keep it smooth & slick so a predator cannot grasp it and bypass it. 
(See the bottom of this post for my DIY ideas for predator baffles).

For mounting my netting above my predator baffle, I use the following materials. 

My 'frame' to hold the netting - a piece of fencing - cut so that there are 'arms (wires)' to support the netting and hold it out
approx. 8" from the pole.

The top of my predator baffle is mounted up as high as I can comfortably reach. I then set the netting frame on top of the baffle and zip tie it together around the post. I can then just cut the zip ties and lower the system for nest checks later, then re-secure the frame with new zip ties.

The netting is approx 3/4" (you can use both 1/2" or 3/4") mesh layered & 'poofed' out and hooked on the wire frame hooks. The netting is available at Lowe's, Walmart, etc. Here's a direct link if you want to order from Walmart: https://www.walmart.com/ip/Easy-Gardener-604-7-x-20-Bird-X-Protective-Netting-For-Fruits-Vege/21945377

 

Electric Fence Guards: Some landlords prefer this method and if you know anything about electricity, then this is the absolute best way to go. You'll want something insulating your pole to ensure your pole itself is not electrified. The landlord below uses a four-foot tall piece of PVC pipe around his pole, then wraps that with approximately 24" tall hardware cloth. The hardware cloth is then attached to the 'live' wire. The few inches open at the bottom are left in case a bird comes in contact with the pole, he / she won't be electrocuted.

Photo provided by Malcolm Stephens, an experienced landlord who takes the protection of his very large purple martin colony very seriously.

You can either purchase a solar-powered fence charger or buy one such as the one below and enclose it in a weather-proof container.

Photo provided by Malcolm Stephens, an experienced landlord who takes the protection of his very large purple martin colony very seriously.

I am not an expert in this area, so if you'd like to try this method, you can either: Login to either of the most popular Facebook Purple Martin Forums (Purple Martin Fanatics or the Purple Martin Conservation Association) and ask for assistance with setting this up, or if you don't have Facebook, send me an email at purplemartin@centurytel.net and I will put you in contact with an expert who can advise you.

Snakes - Large & Small

Friends have shared their pictures with me of successful 'captures' of the snakes that never made it into their housing:

Snake ID: Texas Rat Snake

To remove any captured snake, hold the snake by the head while wearing heavy gloves and use scissors to cut the netting away from the body.  Snakes should be removed unharmed and released a few miles away from the colony.  Netting does not prevent raccoons from climbing the pole and should always be used along with a baffle.  Netting is a trap, rather than a guard and like all traps it needs to be closely monitored to ensure that any species caught by the trap are removed and released unharmed. **PLEASE NOTE: we should value our native predators and NOT kill them - they serve a purpose in our environment.

Snake ID: Texas Rat Snake

Don't let anyone tell you a snake cannot climb a pole - there are multiple recorded events showing they really can.

Photo provided by Greg Ballard - a southern purple martin landlord, where the rat snakes are HUGE!

Purple martins are at their most vulnerable when sleeping inside their nest cavities at night and have very little chance of escaping if a wily racoon or a snake comes calling.

From the PMCA: Once a snake has digested its meal and left, there are no signs that a predator has visited a site, other than missing eggs and birds.

 The next video is hard to watch (spoiler alert - the female, thankfully, escapes). But, I can't imagine putting my purple martins through this kind of terror. (Video credit: Dan Pancamo)

A landlord removed his predator guard for only ONE NIGHT. The snake in the picture below took advantage and wiped out all 4 nestlings overnight by eating 3 of them and the 4th was found dead on the house porch. How would you like to open a nest compartment and see THAT staring you in the face?

Snake ID: Texas Rat Snake

Snake ID: Black Rat Snake (Missouri)

A new landlord here in Missouri added the netting to her pole right after her first 2 purple martins arrived at her colony. She really didn't think anything would go after only 2 birds, but a few days after mounting the netting, she caught this snake before it destroyed what would have been her first and only pair of nesting purple martins.

The "Other" Ground Predator  - Raccoons

Raccoons can be found natively throughout most of the US and Canada, as well as in parts of Latin America, from Mexico extending down to the northernmost regions of South America. 
Raccoons are agile climbers, handling both wood and metal poles easily. Signs of a raccoon attack are finding severed martin wings on the ground, blood, fur and feathers on the martin housing and ground, and claw marks on wooden poles. Nesting material maybe hanging from entrance holes and doors may be pulled off.  

A landlord reported that nesting material had been torn out of each nesting cavity on this Trendsetter house. The torn-off wings and feathers were left on top of the house - a classic indication of a raccoon attack.

Feathers and a bent owl guard were clear signs of a raccoon attack.

Landlord Testimonial (northern Missouri): We left for a 4-day weekend and when we returned all three of our gourd racks (72 gourds) were totally empty. It was only early June (too early for the martins to have left already), so we knew something was wrong. After talking with Kathy and then lowering the housing and viewing the ground below the racks, we discovered that a local raccoon family had likely raided our gourd racks over the weekend. It was a bloody slaughter - feathers and torn off wings on the ground beneath the racks. We had seen the family of 5 raccoons in our nearby woods, but we did not have guards on our poles since we had no idea they (raccoons) could climb the poles.
**Note: It has been over 3 years since this attack, and no purple martins have returned to this site.

I always have at least 4 or 5 raccoons in a family here on Gobbler's Knob too. Last year, while monitoring my housing with a security camera to see what my resident Great Horned Owl was up to, I caught one of the raccoons on camera as he waddled across my yard and tested each guard to see if he could ascend and have a meal of purple martins. (He's hard to see, but click on the YouTube link after you hover over the video, then enlarge it - he enters from the left - watch for the movement).

With a decline in the number of landlords across the country offering housing, it becomes imperative that we offer safe housing to the birds we host. And, for the new landlords that are attracted to this hobby, it's really the responsibility of the experienced landlords to teach and help them provide safe housing. Really. It's not that hard, and with all the experienced landlords on the various forums, help is at your fingertips.

Our purple martins exhibit a lot of trust & faith in us by returning to our sites. It's up to us to not betray that trust by providing them with the needed protection.

A very special thanks to Louise Chambers for her most patient help with editing and providing some very helpful guidance in writing this post.

For more help dealing with aerial predators, you can access this link on my blog:
https://kathyfreeze.blogspot.com/2015/01/the-fob-part-3.html

More links for DIY guards:
https://www.zbestvalue.com/baffle0001.pdf
http://www.zbestvalue.com/baffleimprovements.htm

Predators are on the Prowl

As we replenished the mulch in our landscape bed by the house last Saturday, Bob told me to turn and look at who was being nosey.  She was lying stretched out on the mulch, warming her long, lovely, green-speckled body.  This is one of my favorite snakes in Missouri - the speckled king snake - (see information on them and other snakes here): http://fisheries.tamu.edu/files/2013/10/Snakes-of-Missouri.pdf.
We had scared a mouse out of the old mulch and it had run right into the same hole from which she had emerged.  I liked to believe she came out to express her gratitude; what are those lumps in her body, anyway?  Check out the description of her foods in the picture caption below - "including venomous species"!  Bonus!

Speckled King Snake, sometimes also called, "Green" Speckled King Snake - non-venomous. Foods include rodents, bird eggs, small birds, lizards, and other snakes, including venomous species. It is immune to the venom of the various pit vipers in Missouri. The speckled kingsnake kills its prey by constriction.

With the warmer weather being more consistent now, the snakes are starting to move, as well as other ground predators, including raccoons, so it's time to ensure there is protection not only on your purple martin housing, but also on your bluebird, tree swallow and chickadee nest boxes!
We had placed 6" pvc pipe on some of our 4x4" posts, but we have been moving to stove pipe now.  It seems to be a longer-lasting material and has not faded and gotten as rough on the sides as the old PVC has.

This is 6" pvc - due to be replaced by the better-quality stove pipe.  A TRES pair discuss proper territorial boundaries with another interloping male.

The 8" stovepipe snaps together easily and with a coat or two of wax each year seems to be the best protection against climbing predators.  Albeit, there is nothing I can do about the woodpeckers enlarging the holes, or rather, nothing I really WANT to do about it.  If they want to nest there, let them nest.

I know I have raccoons and snakes about, so predator guards get put on all my nest box poles, even the ones that are mounted on T-posts as the one below.  By the way, I found out the hard way - these little rubber "catches" on the nest boxes below are absolutely no match for the strong talons of a Great Horned or Barred Owl.  We found one pulled open one misty morning and the adult female and her chicks had been killed, so now I drive a screw into the door from the side to keep it solidly closed when a flying predator attacks.  

This is a great video showing some different options for predator guards for your nest boxes:

For my purple martin poles, I have purchased the 'quick release' predator guards from the PMCA.  It makes my life easier with being able to quickly remove these guards as I do nest checks every weekend on these 4 systems.  I mount the inside support of this guard as high as I can reach (I'm 5'3" tall and my reach is comfortably about 6'8" high).  These guards are then high enough that a raccoon or squirrel cannot easily get above them and climb on up the pole.

As added prevention, some people also add netting on their poles. You can purchase what's commonly called "bird netting" in the gardening section (intended to keep birds from stealing the fruit from your fruit trees) of Walmart or other stores.  The netting with the 3/4" openings are recommended to stop larger snakes. 

Scroll through these posts to see some ideas of how to mount your netting to effectively prevent the snakes from climbing your martin poles:
http://www.purplemartin.org/forum/viewtopic.php?t=29210&highlight=snake%20net

Other options for mounting the netting to your poles (good pictures of a very angry, large black snake from Louisiana in this post):
http://www.purplemartin.org/forum/viewtopic.php?f=2&t=27233&hilit=double%20layer%20net%20trap


Please note - the netting will NOT stop climbing predators such as raccoons, so it is best to use both types of protection.  In order to keep you from having to remove multiple snakes from your netting, the netting is best placed above the metal predator guards - and if you use a good metal predator guard, you shouldn't find any snakes in your netting anyway.  Mounting it above also keeps the raccoons from using the netting as a 'boost' to help themselves get over the metal guards.  After all, who wants to go out and wrestle with a raccoon, feral cat, squirrel or possum who is tangled up in their netting?  Thanks to all these preventative measures, the least of my problems come from the ground predators.
A last note about releasing snakes from your netting; as I mentioned above, our native snakes contribute to a balanced ecosystem.  With my speckled king snake and prairie king snakes roaming about (even nesting in my landscape beds), I have yet to encounter a Copperhead around my house.

Prairie Kingsnake - Photo taken 2014, by Aya Katz, Missouri. See more of her pictures here on her blog site:  http://notesfromthepens.blogspot.com/2014/10/the-weather-and-creatures.html

Without the good snakes, we would be overrun with venomous snakes, rodents, and other prey species.  You can easily remove the snake from the netting by grasping the snake behind it's head and cutting the netting to free it (yes, you'll have to replace your netting).  Place the snake in a 5-gallon bucket and move it to another safe territory, but please, do not kill it.  Love'em or hate'em, we need more of them to keep our environment in balance.