The Bigg Bird Forum

Silver Sparrow · Posted: Tue Jul 11, 2006 6:21 pm Post subject: Audible bats

Am i missing something here? We used to have bats about 6 or 7 years ago (back in my GCSE days wo00o0h0000) they lived in the church i think. anyway, we could hear their sonar thingies very clearly, they'd even come quite close and nearly swoop over our heads sometimes!

now all the articles on bats say u need that special equipment to modify the bats sonar thing to make it audible to human ears, but our bats were very much audible without any equipment at all. whats going on?

Martin · Joined: 03 Nov 2005 Posts: 843 Location: Stevenage, Herts

age

as you get older you lose more of your high frequencies

I think a device was demonstrated as an effective method of dispersing unwanted youths by emitting high frequencies that only humans below a certain age could hear !

Tricia · Joined: 08 Apr 2005 Posts: 3579 Location: Surrey

Silver Sparrow · Posted: Wed Jul 12, 2006 2:49 pm Post subject:

but even my parents could hear it and they were in their late 40s! are we just abnormal... and could this be the reason we could ALL hear the cat repellent (my mum is now in her 50s and she heard it too)

Hampshire Hogg · Joined: 28 Nov 2005 Posts: 119

Another myth is dog whistles.

Where we walk the dogs a lady we know always calls her dogs with a special dog whistle.

The dogs appear to ignore it, but it takes the top of my head off every time she uses it.
I'm 74 ! and my hearing is not what it was, so it's effectiveness is suspect.

I once read an artical by a top wildlife expert who visited the Amazon to make a written record of moths.
He sat outside his tent with his yellow labrador who, as soon as night fell went berserk and refused to leave the tent.
It took him some while to realise that it was the sound from bats which was driving the dog mad.
To a dog it must sound like an express train coming straight at them.

Silver Sparrow · Posted: Mon Jul 17, 2006 6:50 pm Post subject:

Does anyone know of any recordings of bat calls available for download - at the original frequency? i want to do a little experiment

Nobby · Joined: 24 Mar 2005 Posts: 327 Location: Kenley Surrey UK

Silver Sparrow · Posted: Sun Jul 23, 2006 3:08 pm Post subject:

I was wondering about that. But then if mobile phones can play those high frequencies I'm sure my Pc could.. unless of course the story of the ultrasonic ringtone was just a bit of fiction.. like those stupid baa baa rainbow sheep stories everyone always falls for Rolling Eyes

the problem is how to get hold of a sound clip in the first place.

Hampshire Hogg · Joined: 28 Nov 2005 Posts: 119

How do you know when you have got one.???

Silver Sparrow · Posted: Tue Jul 25, 2006 9:56 pm Post subject:

what? good speakers?! LOL who knows! its an experiment bound to failure, but one that i want to try anyway Cool

Nobby · Joined: 24 Mar 2005 Posts: 327 Location: Kenley Surrey UK

Do bat sounds have side tones?

I mean if they produce sound at 44KHz then they would also produce a 22KHz sound at half power.

Perhaps a human with good hearing is hearing this sound?

Brett.

Karwin · Joined: 24 Mar 2005 Posts: 2554 Location: 61N25E

Twenty years younger I remember having heard Eptesicus nilssoni. It was like tinnitus from inside my head, but I noticed I heard that always when the bat flew over my head. Here is instead ultrasounds of Eptesicus & Myotis progressed with Pettersson D200 bat detector. The video is by Finnish Association for Nature Conservation, recordings are by me Cool

http://www.youtube.com/watch?v=DOZP7MYVD_s

Peter · Joined: 21 Apr 2005 Posts: 772 Location: South-west England

Karwin · Joined: 24 Mar 2005 Posts: 2554 Location: 61N25E

Karwin · Joined: 24 Mar 2005 Posts: 2554 Location: 61N25E