Protect Cavity Nests, Tree-mounted Nest Boxes and Feeders – Effective Predator Defense
How to Protect Cavity Nests, Tree-mounted Nest Boxes and Feeders - Effective Predator Defense Taking drastic measures to keep the nest safe?
This project shows what methods I used to create a predator defense system, protecting a nest that Northern Flickers built in our apple tree. This same treatment should also work for other cavity dwellers and for tree-mounted feeders of most types. So far, no creatures (that do not fly) have been able to get to the nest. See the video on Creating a Cone Baffle just below the Cavity Nest Video.
See how we built a simple, inexpensive nest box for woodpeckers since this one was becoming too small for so many babies!
Predator protection system - defend cavity nesters, tree-mounted feeders
Easy way to create a Cone Baffle
When a pair of Northern Flickers found our apple tree, they decided to make it into their perfect home. They spent weeks hammering, drilling and excavating to make a cavity nest to raise a brood in.
While we were excited to see them moving in to the neighborhood, we were pretty concerned that the nest was vulnerable. Normally, they choose to make their nests higher off the ground. Since this one was only about six feet up, it would be easily reached by most predators.
We have lots of raccoons and cats that would think of the nest as a cafeteria, and squirrels that would love to move into such spacious digs. We had to act fast!
Version 1.0: The first attempt worked pretty well, or so we thought. Bird B Gone bird spikes were a great idea! I lined both sides of the tree trunk on either side of the nest, and then put two rings of both above the nest, and two below. With so many spikes, it seemed to be a great solution, and it was… for cats anyway.
We put up a security camera to watch the nest. We began to notice squirrels were getting past the spikes. The scary moment was when a raccoon managed to somehow get around them and was caught on camera reaching into the nest, attempting to grab the female Flicker who slept in the nest at night. She didn’t sleep in the nest again for weeks after that.
The problem turned out to be how the bird spikes were mounted. I had them cinched down with long zip ties, but those had enough flexibility that the raccoon’s weight allowed them to bend, thus not being spiky at all! The other issue is that the squirrels were light enough to just stretch over the spikes.
Since the bird spikes were not preventing access or even deterring the marauders, I had to up my defense! I decided that if they couldn’t hold on to anything, they wouldn’t be able to stay on the tree long enough to cause problems. With two apple trees and a fence all near the nest, keeping these bandits out of the trees was unrealistic, and I actually like the squirrels—just not in the nest.
Armor is the solution I came up with. I used sheet aluminum (roll flashing from the hardware store) and surrounded the sides and back of the nest for several feet above and below. Then, to prevent creatures from jumping from the ground onto the uncovered front area around the cavity, I made a cone baffle (see second video above).
Then, I put the bird spikes back up and doubled the amount in an offset, overlapping pattern. This time I only placed them above the nest, and I used screws rather than zip ties.
The metal was very shiny and I don’t think the Flickers would have been too enamored with all that bling, so I painted it with two satin-finish colors in a sort of camo pattern. All in all, it seems to blend in well, and the Flickers didn’t give it a second thought.
I must admit, the sheet metal doesn’t look as intimidating as all the spikes did, but this time around, it has been very effective. We, and the Flickers are pleased to announce that five babies were born and raised in the nest last year! And currently, they are prepping the nest for another brood this year too!
The videos above contains more detail about the design of the protection system, and fabricating the metal cladding and the cone baffle.
Summary of Steps:
- Make a sheet metal cone baffle using free software linked below
- Attach it and sheet metal cladding to the tree
- Spray paint the metal in a camouflage pattern
- Add bird spikes
- Add a wireless security camera
- Watch your bird parents bring up a family!
If you have any tips or tricks, especially for excluding Starlings, please make sure to leave a comment below.
Disclosure: Some of the links below are affiliate links. At no extra cost to you, I may earn a small commission on items bought using them. These are the same recommendations I would make regardless of any compensation. For products that I have older versions of, I recommend the items that I would replace them with if I were buying them new.
Resources for Protecting Cavity Nests, Tree-Mounted Feeders
Cone Calc for Windows, OSX, Linux
Greatly simplifies the math involved in creating a cone baffle
Cone Calc 3D for Windows, OSX, Linux
Adds full-size printouts, 3D visualization, multiple segments. Full function trial may be all you need.
REOLINK Outdoor Wireless Security Camera, Solar Powered, 1080p, 2-way audio, night vision
Great way to see what’s happening when you aren’t looking!
9-3/4 in. MetalMaster Compound Action Straight Cut Snips
For cutting sheet metal for sheathing and cone baffle. PLEASE wear gloves to protect you from sharp edges!
12 oz. Protective Enamel Satin Dark Taupe Spray Paint
From Home Depot
Use colors that blend in with your yard
20 in. x 25 ft. Aluminum Roll Valley Flashing
From Home Depot
Sheet metal for sheathing and cone baffle