Sunday, January 23, 2022

Magic Halo 3-years in Review

To start 2022 in a good direction, let’s recap the most critical articles of the past few years. Some of our customers have passed the 3-year warranty point of their Magic Halo, and should be mindful of the toll that the elements may take on it. We carry all replacement parts at lower cost than retail from e.g. Lowes or Home Depot, available just by emailing us. Replacement wire sets are already offered on our products page. We will also have a Halo tune-up and safety check video coming out with the Spring edition of our newsletter. In the meantime, please review these past titles for anything that may help your bird-feeding and Halo experience:

It is important to note
that Magic Halo is a not for profit, conservation-minded cottage industry. We do everything we possibly can to minimize cost, and bring you this product at the lowest price possible. If you were to round up the parts individually at e.g. Lowes, it would cost you more to build one of this quality yourself – never mind the labor involved. Just the 24 AWG wire roll alone costs $6, for example. Therefore, we are very happy that we can bring this product to you -- and it arrives with minimal assembly required!  😇

Sunday, November 21, 2021

Magic Halo Newsletter, Autumn 2021

Web version HERE. Includes:

  • 2021 Efficacy Survey almost to a close
  • 2022 Survey will seek innovative input
  • Magic Halo safety video set for 2022
  • Other News/Misc

Tuesday, April 27, 2021

Mainly positive survey results into mid-Spring

Our ZoHo Magic Halo Survey results appear to be strong, or about 85% of customers report that the halo is helping reduce or even eliminate House Sparrows (HOSP) at their feeder. This appears commensurate with Sialis' estimate of a 88-94% deterrence rate in Winter and 84% in Summer.

For those of you that don't already know, Survey Monkey grew intolerant of us "freeloading" (using the free version for years) and forced us to switch platforms as of February. If you were among dozens of customers who took the Survey in early 2021, and haven't already re-taken it, we hope that you will HERE. It is only 3 easy multiple choice questions with a comments section.

If you are among ~15% reporting poor or failed results, you can email us (include a photo of your feeder and halo, if possible) for troubleshooting measures that we hope will turn things around for you. Please be sure to read our User Guide first.

As always, thank you so much!  --Admin

Monday, April 12, 2021

Are neighbors to blame for drop in Halo efficacy?

The view over the fence into our neighbor's yard
As always, and in spite of good survey results, we at are striving to learn why there can be a significant difference in House Sparrow (HOSP) behavior from year to year, and from one Magic Halo user to the next.

Starting in 2015, we were 100% HOSP-free at our feeders with halos. Given the success, we designed and produced our own Magic Halos for on-line sale. Then last year, for the first time, our halo efficacy dropped by ~20%. HOSP were now part of the feeder mix, albeit brief visits -- not full time or to the exclusion of native birds. Now in Spring 2021, HOSP are a regular presence, with young adult pairs going around menacing our nest boxes and platforms that are designed for native birds that include Chickadees, Wrens Mourning Doves, Robins, etc. The Halo continues its job in deflecting most HOSP from the feeders, at about 80%.

What changed from 2015-2019 to 2020? We fed through the entire year in 2020, including Summer, which may have contributed to the issue of HOSP juvenile Halo adaption/immunity. But a recent look over our fence may provide an even better explanation. Our western neighbor installed multiple nest boxes, well designed and situated for HOSP. We think this may have begun in 2019, but cannot be certain since we rarely looked over the fence.

Purple Martin house overtaken by House Sparrows
A weakness of the Magic Halo is HOSP juvenile immunity and adaptation into adulthood. If your neighbors are providing cavity nesting sites, they can rapidly multiply, with your yard and gardens as their home territory. If the young birds are using your feeders as juveniles, then it is possible that no counter-measures will deter them, because they will have grown into its presence. This is a theory, that just happens to match the evidence. But it makes a lot of sense.

It is much better not to install a nest box than to allow HOSP to reproduce in one. Unfortunately, many boxes are sold on the cheap, in stores like Home Depot or Lowes. These often have 1.25"+ entrance holes -- the minimum diameter that HOSP can fit through. These (and sadly, many Purple Martin communal houses) end up as breeding meccas for HOSP. Without active education at the point of sale, most buyers believe that they are "helping wildlife" regardless of species occupant. Even some specialty stores avoid the topic, and even encourage their customers with HOSP feeding and nesting. They may be afraid of the perceived monetary loss (selling less seed). On the other hand, they should know and understand the non-native, invasive and damaging nature of HOSP (and Starlings) on the north American continent. Any gains made by Bluebirds, for example, are largely owed to conservationists who are up to the task of monitoring and evicting HOSP from nest boxes. For those of us living in urban or suburban areas, simply dropping the hole diameter to 1.12" (1 1/8") will safely accommodate native species such as Chickadees and Wrens while excluding HOSP from entry.

As part of our ongoing Halo experiments and efforts at continuous improvement, we began trapping and clearing HOSP from the property in the 2nd week of April. Halo efficacy has returned to almost 100%, given that it disrupted this newly created colony as described above. In a return to years past, we are taking down our feeders for the June-Aug time period. We also wrote a friendly letter to our neighbor, explaining the HOSP problem in the hopes that they will adapt their boxes with hole size reducers and distribute them properly. Stay tuned on these efforts.

Humans created this problem 150 years ago by deliberately releasing HOSP mated pairs in urban centers across the U.S. Now we must try and reduce them, using all the tools in the toolbox. This includes halo/hoop devices, spookers, traps, or whatever means are necessary. Below are several valuable links you can use in your own efforts to control the scourge of HOSP, and maximize your Halo's efficacy and thus help native birds:

Managing House Sparrows (the most comprehensive guide, includes site map and history)
Magic Halo User Guide (measures to improve your Magic Halo's efficacy)
Backyard Birds (YouTube videos that include trapping and eradicating)
House Sparrow Control (Facebook)
Birdhouses, Bird Feeders & Garden Designs for Native Species (Facebook)

Sunday, February 14, 2021

Is your feeder wasting bird seed? Quick tip on what to look for

One of the most puzzling aspects of bird feeding is how poorly designed most feeders are. It is not uncommon at all to hear folks complaining about refill rates, sometimes multiple times per day. When factoring the cost of good quality seed, this can become very expensive. Fortunately, just sifting through the ground "waste" (usually full of whole, uneaten seed) may provide the clues needed to remedy the situation.

Most commercially available feeders are designed to bring the seed level up and even with the station edge (tube) or trough edge (hopper). That, or with little raised edge to spare. This results in seed falling out even with the tidiest of native birds eating. House Sparrows and Starlings accelerate the problem, by deliberately throwing seed overboard thus emptying these feeders in a fraction of the time. Good design goes a long way toward reducing this.

When choosing your feeder, don't be afraid to ask for a seed fill-up demo to verify that waste is minimized. In the case of a tube, you can easily examine this by looking at the station roof trailing edge. You want to ensure that it comes down at least even with the station edge itself. If it does not, it is likely that the seed will come up too high and readily spill out. The below photos more than illustrate this problem:

Above/below: Avian Woodlink Series feeders (white) are correctly designed. It is clear in these photos that the station roof trailing edge comes down even with the station edge itself. The result is seed staying in the feeder, with birds having to reach in that little bit further to access. Debris (husks, in this case) and some dropped seeds are contained by the tray below, giving it a second chance among platform-friendly birds e.g. Cardinals. 
Above: A closer look at the Woodlink. The seed (in this case Black Oil Sunflower) is well contained in the station and will not spill out on its own. This is what you want to look for when selecting a feeder. Ask for a seed fill demo if necessary, but a look at the station roof line is usually enough.

Above/below: An inexpensive tube feeder purchased at Lowes. The above (and below, with Safflower) are exactly what you don't want in a feeder design, which accounts for most store-bought models unfortunately. You can literally empty these feeders with barely shaking them. During normal feeding, multiple seeds fall out for each one taken and eaten. The ground below your setup will quickly accumulate whole seed, and unless you have hoards of ground feeding birds, it may start to germinate -- probably by Spring.

Above: A closer up look at the Lowes no-name brand feeder, this time with Safflower. This is a 100% terrible design. The station roof trailing edge is split, and makes it only halfway to the station edge itself. If we were to use millet-types seeds which have lower viscosity, this feeder will literally empty itself sitting still.

In summary, avoid any feeder where the fill line of the station edge(s) isn't at least 1/8" lower, otherwise your bird seed will not stay in the feeder even under normal feeding conditions.

Sunday, February 7, 2021

PLEASE READ: Magic Halo 2021 Efficacy Survey 2.0

Please take or retake the Magic Halo Efficacy Survey for 2021 (2.0), by Zoho

Survey Monkey stripped features from our 2021 survey to the point it was dysfunctional and useless. First, they made the comments field a paid feature, which we needed for feedback and testimonials. Their latest move was to cut our number of visible survey results to 40, after we reached 48 and were hoping for 50. This is less than half of what was allowed for unpaid accounts. In a "nutshell", they want us to pay $33/month to run a single survey for an entire year, that has little chance of seeing 100+ participants anytime soon.

That said, we switched to ZoHo, a refreshing new platform that, unlike Survey Monkey, won't put the squeeze on us over the longer term. Simply said, we're not paying $300+/yr for what amounts to very little usage.

We would sincerely appreciate your participation (or re-participation if you already completed the 2021 Survey Monkey survey, even recently) which has been deleted with data unavailable. We lowered it to 2 Questions and an optional comments box, which can be used for feedback or a testimonial. We basically need to replace what was lost, with your help. Click HERE to access the new survey, with only seconds of your time required..

We thank you so much and appreciate your understanding!

--Frankie (Admin,

Thursday, February 4, 2021

Quick Tip: Use a tiny binder clip to shorten hanging wires

Some of our customers have shown an interest in shortening their Magic Halo hanging wires. One customer claims that the weighted ends (hex nuts or bulbous sinkers) must fall even with the feeder trough or lowest station edge in order to work effectively. There is no hard study data making the case for wire length. In fact, in the original U of Neb paper, the "lines" (twine) were not weighted, but instead extended and pinned to the ground below for tension. Given that, we still believe that the weighted ends should fall a few inches below the feeder's lowest point, by preferably 6" or more. But given the subjective nature of feeding birds, and at least one customer's claim, you can always experiment.

If your hanging wires fall well lower than your feeder, there are a few easy methods for shortening them. We recommend "pigtails" using tiny binder clips. Simply wrap the wire around two fingers at the point they connect to the Halo and its crossbar, and clip in place as per the photos (older "Classic" model shown) below. Contact us if you have any questions or need assistance!

Wednesday, February 3, 2021

Customers confusing HOSP with native species

We have seen in the past few months that some of our customers are confusing House Sparrows (HOSP) with native bird species. We have had several complaints and even a Halo returned, citing its failure and that it actually encouraged more "sparrows" by providing additional perch space. Subsequent emailed photos revealed that it's not HOSP crowding their feeder, but Pine Siskins (PISI) or House Finches (HOFI).

As a result, we have updated our Disclaimer and Product Pages to better illustrate HOSP and how to identify them. We urge folks to read about the Pine Siskins and what is going on with that species (among others) and why they are suddenly "mobbing" feeders in the U.S.

The above said, we have been up front at all times that the Magic Halo isn't necessarily HOSP-proof. Our position is that it is a deterrent -- a tool in the anti-HOSP toolbox -- and at the very least, it should reduce them at bird feeders. We encourage folks to read our 2020 survey data and customer feedback and draw your own conclusions before buying a Magic Halo. Thank you so much.

(below is courtesy of Bayou City Birding, and can be found HERE in pdf)

Friday, January 15, 2021

Early 2021 Efficacy Survey Results: Analysis

Our 2021 Magic Halo Efficacy Survey
has just arrived, and the results are flowing in. If you haven't already, please click HERE to participate. It's only 3 multiple choice questions, and 100% safe and secure.

If you have already participated, and are among ~25% reporting poor or failed results, feel free to email us (include a photo of your feeder and halo, if possible) anytime for troubleshooting measures that we hope will turn things around for you: Please take note of the following:

  • If you bought your Halo before Sept 2019, the model "Classic" was only offered with 30" hanging wires in a 4 line config. This was ample length for most ordinary tube and hopper feeders, but the weighted ends fell about even or slightly above the feeding ports on jumbo tubes (e.g. Yankee Flipper, Brome Squirrelbuster Plus, etc). If this is you, we offer free wire extenders to anyone who requests them from before that time period. Email us at:
  • Consider adding additional hanging wires. Some of our customers report this as making the difference. If it is juvenile House Sparrows (HOSP), it may not make much difference, however, given their immunity to halos and lines-type devices in the first place. It's a matter of experimentation. If you are planning to add your own additional wires as a test, just ensure you add makeshift weights on the ends to tension them.
  • Among those reporting poor results, all but one feed year-round. The evidence suggests that HOSP deterrence is highest when the Halo is installed in the Autumn with continued feeding through Winter and mid-Spring. Feeding through the Summer may see Juveniles appear at your feeder, followed by continued immunity with adult adaptation into Winter and beyond. After 4 straight years at 100% deterrence, we fed through the Summer for the first time in 2020 and are having this problem now. We plan to "reset" our feeders by returning to a Fall-Winter-Spring schedule in 2021, and see if we return to 100% HOSP deterrence as in years past.
  • It seems to be the case that the presence of the Halo and its hanging wires does incite anxiety and nervousness in HOSP, and their visits shorter as a result. You may consider removing your Halo for a few weeks, and observe behavior in order to demonstrate any differences in this regard, and their numbers overall. 
  • Seed type and feeder design does not appear to make a difference so far. Husk seeds such as black oil sunflower or safflower still attract HOSP to feeders, where they may decide it's too much work to crack seeds. Because of this, they may move on elsewhere -- making this an effective deterrent in itself.
  • If you are one of those that saw Halo deterrence rates start to drop in the Summer with continued HOSP presence into Winter, consider taking down your feeder(s) by late Spring and reinstall come Oct or Nov. This may have the effect of "resetting" your system, with Juvenile HOSP having moved elsewhere, e.g. neighbor's feeders or other food sources in the region.
  • If you are on Facebook, consider joining one or both of these groups, which include lively discussions about HOSP and the use of Halos and similar means to control them: Birdhouses, Bird Feeders & Garden Designs for Native Species | House Sparrow Control
Our 2021 survey results are following a similar trajectory as years past, that at least 3/4 of users are seeing some level of positive results. We would love for this percentage to be higher so again, if you want us to try and help, email your questions and include a photo of your feeding station setup for analysis: Thank you so much! --Admin, Magic Halo

Monday, January 4, 2021

2021 Magic Halo Efficacy Survey Has Arrived!

Our 2021 Magic Halo Efficacy Survey has arrived. Please click HERE. It's only 3 multiple choice questions, and 100% safe and secure.

Even if you just took the 2020 survey, we ask that you please take this one too, and anytime a new one is presented. This is your chance to record your results, positive or negative. You can also let us know if you have stopped using your Halo for any reason.

 Halo efficacy can vary over time. Like FeederWatch, your data helps determine how best to market the Magic Halo -- which in the long run helps wildlife conservation.

Before you begin, please be sure of what you are seeing, that you can fully identify House Sparrows (HOSP). Do the best you can to compare before vs after, with vs without using the Magic Halo.

Try not to count juvenile HOSP, which are immune to Halos and other lines and wire devices. These can be difficult to discern from adults as the Summer goes on, if you feed year-round.

Visit our website for articles, mods and additional products that may help you to improve Halo performance.

For all issues and inquiries, please contact us at: Thank you so much!

Sunday, January 3, 2021

Magic Halo Newsletter, Winter 2021

Web version HERE. Includes:

  • 2021 Efficacy Survey Has Arrived
  • Possible HOSP Juvenile to Adult Timeline?
  • Bye bye UPS; back to USPS
  • Other News/Misc

Tuesday, December 8, 2020

Possible House Sparrow Juvenile to Adult Timeline

Thanks to Cornell U's Lab of Ornithology, we might have a better understanding of when House Sparrows (HOSP) fully mature. Juveniles are generally immune to halos and other lines/wires devices. According to this infographic, HOSP may not reach adulthood until sometime in mid-Nov, on average, throughout its range. We continue to wonder if continued adaptation is the case, especially if HOSP are resident and mature on site, where you live.

A single HOSP pair can spawn 10 to 20 fledglings per year. If you are one of only a few feeders in the neighborhood, they may be abundant -- regardless of seed type you are using. We know that the Magic Halo isn't always 100% effective, and in some cases, may only "help". Juvenile populations may account for that, since they begin to resemble adults as the post-nesting season goes on. Despite this issue, most folks will acknowledge that they are still better off using a Halo than not. Read about HOSP proliferation, courtesy of Sialis, HERE.

Sunday, November 29, 2020

Magic Halo Newsletter, Autumn 2020

Web version HERE. Includes:
  • Hanging wire clips will rust (but not to worry)
  • Test Cast: Year-Round Feeding
  • 2021 (brief) Efficacy Survey TBA
  • Other News/Misc

Test Case: Year-Round Feeding

Since 2016, we have been feeding birds from Fall through early Spring using halos, starting out with the original Bird-X model. Then, upon its disappearance from the shelves, we started hand making and selling our own. Theirs or ours, House Sparrows (HOSP) were 100% eliminated -- not just from our feeders (2, pure black oil sunflower and safflower), but from the entire gardens it seemed.

After 4 HOSP-free years, for the first time, we decided to keep the feeders going year-round (2020), to ensure Halo efficacy remained consistent during the hot weather months. As it turned out, this was not the case; at some point during mid-Summer, a single HOSP would appear at a time. Then one became two, and then a few at a time as we entered late Summer and Fall. Now as many as 3-5 HOSP can be seen at a time making it through the hanging wires, but their behavior at the feeder is usually nervous and erratic, and they usually don't stay long (some longer than others).

So, in order to test efficacy, we did a few experiments. We found that removing the Halo does bring about a surge in HOSP numbers, and makes them more comfortable and thus more aggressive at the feeders. Therefore, at least in our observation, keeping the Halo up still serves as a deterrent and helps reduce seed consumption -- and thus cuts refill rates and costs. If this wasn't the case, we would have to consider ending Magic Halo production and quit selling the device. We hope it never comes to that.

So the question becomes, how did this happen, after years of 100% HOSP-free feeding? It is impossible to know without a university taking up the cause with scientific studies. But the most plausible theory has to do with leaving the feeders up through Summer (year-round). It would seem likely that HOSP juveniles nesting nearby (20 chicks avg per year per pair) commandeered our gardens in Spring, making it their territory and regular source of food. As first year birds, they started out immune to lines (wires), as shown in the original U of Neb studies. As the season went on, continued adaptation followed. Given this observation, we had to update our disclaimer to further emphasize the issue of juveniles and that Halos are best viewed as an adult HOSP deterrent, not "-proof" though many folks continue with feedback that it is (and it was for us, until this year).

We hope this helps our customers understand, and to continue using their Magic Halo as just one tool in the toolbox in the effort to reduce or eliminate HOSP from their feeders. Each year, we offer a new survey in order to keep efficacy data rolling in, so please participate as much as you can. Our surveys do not require any personal info and are 100% safe and secure. If you haven't already, please take the 2021 Survey. Written feedback ( with attached photos of your feeding setup is also very much appreciated, and will be considered for this blog. As always, let us know your experiences using the Magic Halo!

Sunday, November 22, 2020

Hanging hardware will rust or tarnish (but not to worry)

We've had customer concerns regarding rust overtaking the Halo's hanging wire clips. At this time, there isn't much we can do about this issue. Other than their aesthetic appearance, functionality is not effected nor is it for other parts. This clip is the highest quality and most suited to our purpose of hanging weighted wires from the Halo, but it is chrome plated steel. We are not able to find a commercially available, weather-proof clip that is similarly sized and designed.

That said, if any of you are aware of a clip that you think could work, and maintain its appearance through the elements over years time, please email us at with a link. We are open to trying new components and offering additional options if the demand is there. Until then, we maintain our 3 year warranty on all parts of our Magic Halos regardless of location and weather conditions -- though we expect them to last longer even with rust discoloration.

Saturday, September 19, 2020

Magic Halo Newsletter, End of Summer 2020

 Web version HERE. Includes:
  • A check of your strap hanger for tightness
  • 2020 Survey contest winner
  • End of Summer survey results
  • Replacement wires now on offer (with elegant weights option)

Sunday, September 6, 2020

Strap Hanger Safety Inspection

We saw it recently where the strap hanger on the Magic Halo's crossbar began to loosen, with one or both pan head screws lifting up from the threads. We think this is extremely rare, but are asking our customers (especially long time users ~2018) -- to periodically inspect this part of the Halo to ensure it is snugged properly. It is important because we don't want to worry about feeders crashing to the ground; many are delicately made and could be damaged in a fall.

Though an isolated event, it can't hurt to check yours just to make sure. If at all loose, snug both screws down with a philips head screwdriver, being careful not to over-tighten. If you want to doubly insure good purchase (thread security), you can also remove the strap completely and inject a couple of drops of your favorite super glue into both screw holes. This will solidify the threads that are in there. Wait a few hours and then re-install the strap. The same process can be applied to the feeder hook on the opposite side, should any thread instability be detected; this part is easily checked/unscrewed with a counter-clockwise twist. Email us with any questions:

Tuesday, July 7, 2020

Magic Halo Newsletter, Summer 2020

Web version HERE. Includes:
  • 2020 Survey Contest Winner Announced!
  • Halo leveling issue? Try this simple procedure
  • Latest Testimonials and Survey Data
  • New Offering: Replacement Hanging Wires 

Saturday, July 4, 2020

2020 Survey Contest Winner Announced!

Ray Denenberg of Silver Springs Maryland wins a Magic Halo Regal from Winner was drawn from a pool of customers that participated in our 2020 results survey. Congratulations, Ray!

Latest Testimonials and Feedback, 2020

The reason we strive for results and input is to know our product is a success, but also to have this available for potential buyers -- those considering the purchase of a Magic Halo.

Here is what we collected from our 2020 Survey comments, along with our latest testimonials. We did not include names for privacy reasons. Overall, the results are very positive, considering that House Sparrows (HOSP) are one of -- if not THE most adaptable bird in the world and can learn to overcome almost anything.

We thank all of you, the approx 15% of our customers who participated in the survey.


The Halo absolutely has improved the situation. We previously had gangs of HOSP then after the first halo, zero. Recently (May/June) I returned to a mixed feed to attract a wider range of birds and we have seen HOSP pairs breach the halo. You definitely need to pay attention to both seed choice and halo configuration. Together you can definitely reduce HOSPs.

I purchased the Deluxe version with two additional wires since I had a very bad infestation. I tried it first without the additional wires and some were bypassing. When I added the additional wires, they quit attempting to access the feeder.

I’m very pleased you decided to manufacture this product!!!

The halo eliminated house sparrows off my hanging tube feeder/squirrel proof cage (weight triggered). It also cut down on the sparrows which come to all my feeders. Feeders are in a patio area of 15'x20'. Also stopped grackles and starlings from getting on the feeder. and RWBD still get on but don't stay long. Woodpeckers and Chickadees still come in full force. Halo is a big success!

I do think they are reduced overall. Initially they were greatly reduced but over time, they have figured it out.

I just wanted to let you know how much we love and appreciate the Magic Halo we purchased from you about a year ago. We live in Washington, DC, and I truly thought we were going to have to give up our bird feeders because they were just mobbed by house sparrows all the time and it was so depressing knowing we were feeding them. My husband had basically given up on having bird feeders until I ordered a Magic Halo and I truly cannot believe how well it works. I have never seen a single house sparrow on our feeder, while all the other birds flit happily past the wires. It may be the single most impressive product I have ever bought. Thank you SO MUCH for coming up with this amazing invention.

I must have had 20-30 HOSP per day; filled the bird feeder 3 times each day......found out how stupid I was when I read up on what they do! Now I will see 1 HOSP per every few days or longer. It has made life so much better!!

Works great! Have bought two and they both repel >90% of HOSP. Keep it up!

Although it has very effectively repelled all house sparrows, we are also seeing very few native birds, despite their presence elsewhere in our neighborhood. We're not sure yet if that's the halo, the type of seed, other features of the feeder, etc., so we're going to give it some more time and experiment. We're currently missing the House Sparrows a little because there are no birds to watch!

The product has worked great. Our feed is lasting much longer. Yes you can enter me in the drawing. Thank You!

Magic Halo is a great product and it has held up well through the seasons. The Starling and Squirrel mafias have gotten used to it however and it has gradually become less effective. Still, I am happy to have had it and I think it continues to make some difference.

I was being wiped out by Sparrows. They emptied my large bird feeder daily and shut out other birds from feeding. Since I put in the halo, the Sparrows have disappeared and our native birds are back. Now, if I could only get rid of that rogue squirrel......

The Magic Halo paid for itself in a very short amount of time. I don't have to fill the feeder nearly as often and the other birds have returned.

Wanted to let you know that I'm very happy with our Magic Halo purchase. I've attached a video showing it deterring a house sparrow while a finch dines at the feeder. I have a blog and wrote about it here:

I used it over a bluebird house as sparrow kept moving in. It worked! However, the bluebirds haven't moved in...yet. It might be too early as they haven't moved in to their favorite house location either. BUT the sparrows have been deterred from the one Halo I own.

This was immediately 100% effective. Not one house sparrow has used my main feeder in the 2 weeks since I've been using this. I have gone from having 15-20 house sparrows in my backyard to 3 or 4 (they use my other feeders that don't have halos). This purchase was a last resort for me. Other methods, like switching to safflower, and using cling style feeders, had been ineffective. I'm undecided on whether I would purchase halos for my other feeders, as the house sparrows are down to a reasonable number now, and the halo is a bit unsightly. Maybe one day you could make a slightly more attractive model. Maybe something other than nuts could be used to weigh down the wires. Just an idea. I am overall very happy with the product.

The Magic Halo has been 100% effective in keeping HOSPs off my thistle feeder. Goldfinches, House Finches, Siskins, and Juncos still come to the feeder, but the English Sparrows completely stay away.

It is more than a year now since I attached the Magic Halo to my thistle feeder. I have not had one HOSP on the feeder. Not one, even though there can be as many as 30 on the platform feeder not 20 yards away.

I have two of the halos, when I bought them, the only place I could find them was on eBay. I have five feeders, two halos, so the HOSP still can get to three feeders. Those three feeders are on a Shepherd's hook in the yard. The Halo doesn't fit on it. I would love to see one modified to fit the Shepherd's hook, I could get rid of all the HOSP.

It has worked far better than I had anticipated it would. Totally eliminated my Sparrow problem.

I have noticed a slight dip in all birds to the feeder, but a significant drop in house sparrows. Over all I was happy with my purchase.