https://www.magichalo.org/2022/01/magic-halo-3-years-in-revi... https://www.magichalo.org/2022/01/as-we-enter-our-4th-year.h...
We find that, overall, the Halo is about 85% effective according to those surveyed. Cheers, -Francis
Another observation: Because of the number of sparrows, I did pull the whole feeder down and kept it down for months. Then, when winter approached, I put the feeder and the halo back up, and no house sparrows made it through again. Did the adults who were defeating it before forget? Move on? Die? Who knows!
Reminds me of this guy, who thought it would be a good idea to introduce the birds in Shakespeare's plays to the US.
- Resist feeding non-native invasive HOSP to encourage native species
https://www.rspb.org.uk/birds-and-wildlife/wildlife-guides/b...
https://www.rspb.org.uk/our-work/conservation/projects/cause...
https://www.ua-magazine.com/2019/09/25/an-unsolved-mystery-t...
Why so sure? Did you read the papers and have any reasoning to why they will adapt?