Bats (flying rodents) and bluray lasers...

Bats are blind, they "see" by listening to ultrasound. It is very possible one of the components of the laser is making an ultrasound noise which of course you can't hear, but they can.

bats a freaking great.... Anything that eats that many insects every night is cool in my book! I don't care for insects or spiders too much (even though they serve a purpose too).

no, bats definitely are not blind. they rely heavily on their hearing, obviously, but they stop producing ultrasound near their home (batcave?), for example.

yes, they are freaking awesome!

manuel

I found a nest of them, one time, repairing a rolling window (or whatever you call them ) ..... they was funny, looks as little fur balls with wings ..... i left them there, after the repair (anything eats insects and mosquitos is welcome, for me )

The flex drive has been known to make high frequency sounds from time to time. The on spec drives will swith thier ICs at ultra sonic frequencies that could most likely be easily heard by a bat. If your blu rays are being driven by a flexdrive, it might be possible that true bats get alarmed by your drivers! Just a suggestion really, but hey, if bugs are attracted to violet light, why not bats?

The "noise" described by the animal expert would not be a sound wave, but rather some kind light interference or distortion that could disorient or simply agrivate a bat.

But who knows for sure?

I'll be interested to see an experts explanation.

^ not at 2.4 MHz ..... if you mean the oscillator frequency, sorry but no, there's no way that any living creature can hear 2400 KHz as a sound.

If it make different resonant noises, maybe, if they are in the range of 30 / 60 KHz, but don't know how it can be possible ..... maybe the shutdown circuit works in that range, with flexdrive configuration ? ..... have to undertake my old ultrasonic converter an made some tests, maybe .....

nice!
that will answer that question for good!
..an oszi could do the job too.. no idea what sensorhead to use though?

manuel

Wow, I didn't know that the flexdrive went at such high frequencies!

Wow, really cool stuff.

Bats rock! but a rodent is a mammal in the order rodentia while a bat is a mammal in the order chiroptera.

I too have seen different reactions to different wavelengths in different species of animals.

Fish will swarm to a green pointer and largely ignore red, never tried blu ray yet.

Some of my garter snakes (yes I have 50+) will chase around after the green dot, but don't even seem to notice red.

For the curious folks... Thamnophis

Our dog chases the green, but the cat runs the other way, however the cat chases the red????

We have weird animals, so these are just observations not absolutes.

Uhm, still not found a decent chart about color perceptions in different animals, but some informations i found ..... some rhodent and chiroptera classes, have shifted color perception, still trichromatic like our one, but starting in the UV and ending in yellow (so they don't see red), some others are just blind to green and red (like squirrels and related ones), dogs see in the range of blue and yellow (they are dichromatic) and their combinations (so also green, that is blue + yellow), cats see in purple, blue, yellow and green range, but they see red, orange and brown as different grades of gray and white (anyway, they have almost the double of our perception about light level and also more about movement of it, so they probably see the red dot of a pointer as a "ghost image" reflected from other surfaces ..... and, other than this, have you never noticed how a red dot from a laser looks as composed of thousand of little points in continuous movement ? ..... now imagine how it may appear to a cat, that probably see it white, much more bright, and with a sensitivity to the movement 3 or 4 times our one, and you can understand why they chase red dots ) ..... and so on .....

It's interesting, anyway ..... need to find more info about how animals see colors, or not see them .....

Interesting story on the bats - never read it before.

The theory of any noise from switching drivers like the flexdrive could easily be eliminated by powering the diode from a linear current source.

I guess the anecdotes on here are enough to have me thinking there must be something going on, but there are very few bats around here to try anthing on. I'll have to bring a bluray on a trip to asia some time, loads of bats in the warmer countries down there.

It would be interesting to see if all bats react to it, or only certain kinds. There are 2 basic groups of bats, those that feed on insects (or blood) and those that feed on fruits and plants.

This would answer if the light affects the bats directly, or it somehow distrubs insects that make bats go after them or something like that. Insect eating bats are practically blind, so if they react it would give the insect theory, while fruit eating bats actually have pretty decent vision good enough for a direct response.

Perhaps someone here lives near colonies of either kind and could figure it out

How cool would it be to have a bluray beam as a homing beacon to attract bug-eating bats... no more mosquito bites while sitting in the garden

as an interesting note, It is currently believed that at least all mammals can seen blue light. This is not proven, just suspected, due to all mammals have retinal ganglion cells. and it's been discovered that a small percentage of retinal ganglion cells (1-2%) are photosensitive, mostly to blue. however as this puts the total percentage of photoreceptors of this type as less then 1%, some people argue this is not enough, however since retinal ganglion cells are connected to the other cells in your eyes, it's believed they route the signals of other cells to the brain, thus allowing a fewer number of this cell type to provide more input to the brain. Kind of odd. either way, compelling evidence for a blue laser to be more visible to even an animal believed to be colorblind (not that that many animals are perceived as being colorblind still). But still all theory, nothing proven. Just thought I would add my 2 cents.

StridAst

@ Benm: but this also attract flying pests and mosquitos ..... almost all the insects have a great sensitivity in blue and UV range, and are practically blind in red/orange range, and cause they are attracted from light .....

That's why "bug lights" are yellow and bug zappers are UV:yh:

I suppose bluray might attract more bugs, and it would be a bit of a tradeoff.

The bugs that bother most of us the most, mosquitos, don't really need any light to find their human prey - they can find targets by both CO2 exhaled and temperature.

In that regard attracting bugs in general would not be a bad thing, as most of them won't bite but could attracts bats that gobble up both harmless bugs and ones that do.

I suppose the best critters to rid you of mosquitos would be dragonflies, but any environment they thrive in is also ideal for mosquitos (both need still water to breed). Also, they're a lot more annoying to have flying around than bats are, and could even bite you themselves if provoked (trapped under clothing or such).

Very lucky, the swamps I have out back are full of frogs, they and the tadpoles wreak havoc on the bugs and larvae.....

Plus they provide an excellent source of snake food. (the frogs & tads)

Wouldn't it be cool to use a high power blu ray laser AS a bug zapper??

They would be drawn into the beam and subsequently fried by it. (like that scene in the family guy star wars spoof.)