After Tens of Thousands of Pigeons Vanish, One Comes Back | Hacker News Reader

After Tens of Thousands of Pigeons Vanish, One Comes Back

phenomena.nationalgeographic.com

90 pointssrikar24 comments

> Mouritsen thinks, that the reason those warblers left Tennessee was not because they heard wisps of a distant superstorm but because of changes in atmospheric pressure.

Sound is changes in atmospheric pressure, and we're talking about infrasound which is really low frequency, so there's not exactly a sharp distinction here.

There's still a pretty good distinction here. The baseline pressure actually changing vs. the pressure rising and falling every 4 seconds over and over.

TLDR - the pigeon problem coincided with high-decibel infrasound from sonic booms from the Concorde SST. That suggests they were temporarily deafened in that frequency band. (At 11 octaves below middle C, they're sensitive to anything over 0.1 Hertz.)

Is it actually possible to be specifically deafened at such a low frequency? There's no resonance down there, and it would be so much lower energy. I would expect all other hearing to be severely and possibly permanently impacted before infrasound could be deafened.

I'd like something that keeps pigeons off my balcony. Surprisingly little works. I have a motion detecting sonic alarm that doesn't work - maybe it's in the wrong frequency for pigeons. I wonder if a motion detecting laser frightener would work better. Kickstarter anyone?

Have someone bring over their falcon every now and then: http://www.airstrikebirdcontrol.com/

My mom bought a weak super soaker and has been spraying pigeons with water, she says it works.

Not sure I'd recommend it.

You just need to militarize your balcony with Python: https://www.youtube.com/watch?v=QPgqfnKG_T4

Have you tried a feline alarm system? Worked for us.

Thanks. I'd like to give that a try. Do you have a link to the type of model that has worked for you?

I'd get one used or second hand, since they tend to be better at detecting the birds.

sure, but 'feline alarm system' is kind of vague - what type or model worked for you?

You can try with a plastic or resin bird of prey figure.

I've got a feeling in a couple decades the military will declassify how they used some kind of new ULF device to talk to submarines and it had a power level equal to nuclear weapons.

And that as a side effect it screwed up all kinds of wildlife.

Just plain sonar is bad enough, and that's been public knowledge for a while:

http://www.scientificamerican.com/article/does-military-sona...

For sure this is interesting, but it's curious that articles of this sort are appearing on HN with increasing frequency. There used to be purely tech news, now it seems that anything interesting qualifies for an up vote.

"On-Topic: Anything that good hackers would find interesting. That includes more than hacking and startups. If you had to reduce it to a sentence, the answer might be: anything that gratifies one's intellectual curiosity."

A post like the parent and a reply of the guidelines happens multiple times per weekend. I wonder when the complainers will notice the pattern and accept it.

New people come along all the time. I was also confused by the guidelines. Possibly they need to be in a more prominent place.

https://news.ycombinator.com/newsguidelines.html

HN is for anything that gratifies one's intellectual curiosity. The only time it was purely tech news was when it was called Startup News.

Two people have posted the guidelines. Here's the guidelines from 2008, which shows that this intellectually curious thing has been there for many years.

https://web.archive.org/web/20080616133301/http://ycombinato...

> On-Topic: Anything that good hackers would find interesting. That includes more than hacking and startups. If you had to reduce it to a sentence, the answer might be: anything that gratifies one's intellectual curiosity.

Check out pg's (the creator of this site) own submissions: https://news.ycombinator.com/submitted?id=pg

The first page alone includes articles on the migration of monarch butterflies, boardinghouses, income taxes by US counties, doodles by medieval kids, health benefits of eating nuts, and more.

For what it's worth, I love reading HN, compared to other news sites.

It's a refreshing change from say, Reddit's technology subreddits, which are a continuous regurgitation of the same old Comcast, Google, Apple and Microsoft opinions every single day; a thinly-veiled political and astroturfing soapbox at best, where anything remotely interesting in regards to what we're learning about this universe and how our technology applies to it, barely gets above 50 points.

"Tech" is not just computers.

Nonsense, this is of huge interest to any startups and other tech companies using RFC 2549 [1] in their tech stack.

[1] https://tools.ietf.org/html/rfc2549

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