I have an outdoor enclosure, a large cuboid like 30' x 15' by 8' tall, a wooden framed structure covered in chicken wire.

Sparrows can get through the chicken wire and fly around and steal chicken food.

I want to mount some optical detectors inside this, so that birds flying say above 2ft above the ground can be detected.

So imagine two wooden posts 8' tall and 15' apart, how could I do this?

I can imagine an infrared light source, mounted say 5' up onto one post "shining" across to the other post. On that other post I could mount several IR detectors, say 6 inches apart starting at about 12 inches from the ground, using say 14 or so detectors.

Any sparrow flying between these posts would, likely, cause an interruption to one of the LEDs and be detected.

In reality there are many sparrows that come and go in numbers, so its likely the device would trigger reliably, we're not trying to reliably detect single birds with high resolution.

Is there any approach you'd take to this, it sounds like my idea is fine but a bit fiddly, there may be stuff like this already built, arrays of detectors and so on.

Thoughts...?

 

...Is there any approach you'd take to this...

I would try a 'human presence' / 'occupancy' wall switch first to check how well it works with sparrows.

----> https://search.brave.com/images?q=human presence wall switch

There is many flavors; wifi, zigbee, time delay...

 

Hi AK,
Asking the obvious, is it possible to use a 'finer' chicken wire mesh, or double layer your existing mesh size with a 45degree offset.

Have you considered an articulated model of a bird of prey, say with recorded bird 'alarms' sounds?

E

 

Hi AK,
Asking the obvious, is it possible to use a 'finer' chicken wire mesh, or double layer your existing mesh size with a 45degree offset.

Have you considered an articulated model of a bird of prey, say with recorded bird 'alarms' sounds?

E

I have considered netting, covering the enclosure in netting which is cheap but the logistics of covering the enclosure is bothering me.

I'll post a picture shortly of the enclosure.

 

Hi AK,
Instead of the blow up figure to scare the birds, consider a simple figure of a bird of prey that says flaps its wings and emits a bird alarm sound,
Your IR beam will IMO not work as you expect.
E

 

Look into the new millimeter wave (24GHz) FMCW radar modules. They can be programmed to detect all sorts of specific motions and object sizes. They are small, cheap(ish), and very clever. I am partial to HiLink modules but there are others.

 

Check out the RCWL-0516 - https://www.sparkfun.com/products/21242

 

Consider current technology motion sensors as used for security lights. The one I has will sense squirrels at 20 feet. If it does not work like that, add an IR light source so that light reflected from the birds will trigger it. A second scheme would be light beam sensors using small lasers. A few beams along the length would be interrupted by the birds in flight.

 

What are you going to do when you detect them?
I understand chickens are skittish and will stampede if anything spooks them.

 

What is it with chickens, chicken coops, etc. that attracts automation? "Automatic chicken coop door opener" is probably in the top 10 repeat posts here. I say that not in a disparaging way, I'm genuinely fascinated by it. When I had chickens I felt the pull toward it too and I made some pretty elaborate raccoon traps.

I think your beam break sensors will not work reliably. Chickens themselves can get several feet off the ground even with clipped wings and they're a helluva lot more likely to set off your alarm than sparrows are. I wager 9 times out of 10 the alarm goes off, it wasn't a sparrow.

I think prevention is a better solution than detection but if a finer mesh (check out "hardware cloth") isn't feasible then I think the only thing that is going to be able to discern a chicken from a sparrow is AI. Those radar modules sound cool but there's also AI cameras. Check out OAK-D camera, it has AI built in, and should be able to learn the difference between a sparrow and a chicken I would think.

 

Place a perch outside of the coup, and sense on that with a single beam. Place it in a spot that they’ll alight on prior to entering the coup.

 

Place a perch outside of the coup, and sense on that with a single beam. Place it in a spot that they’ll alight on prior to entering the coup.

The outside perch can work. THEN add a voltage source of the type not allowed on this site.