Bat exclude device

I take it you have a fruit bat problem? Oh well, it could be worse; like a belfry bat problem.

I would approach the problem by recording the sound of the bat's. Determine the frequency of the sound with an oscilloscope, getting a copy of some old Radio Shack electronics books and building a high powered sound system that blasts that frequency out into the night.

If it works you can sell them to your neighbors.

Poor Bats; all they are doing is looking for something to eat.

Gavilan

Dear Gavilan;

Thanks for ready to help.Hope you will be success and wish you every success.

Ya;I think can sell so many units, since the fruit bat problem is a menace here in Sri Lanka.

Shanthasl

If your fruit bats are similar to our "flying foxes" in Australia, they don't use echo location like the insect eating bats.

A possibility is to try and find their alarm call and broadcast it at frequent intervals, with some variations so they don't readily adapt.

Another is to mess up their sight by flashing lights in the orchard. The neighbors probably won't be too happy, but it might mess up the bats.

I don't know if it's true, but I have been told that they don't like UV light, which is supposed to be why they come out at night. Bathing the orchard in long wave UV may help. Short wave may damage the fruit or the trees.

Here in Cairns, the Lychee farmers were using an electrified grid above the trees to catch and electrocute the incoming bats. Apparently effective and cheap until the EPA banned it.

The farmers now simply net their trees during the fruiting season - expensive but effective.

It is incredible how quickly these bats can strip an unprotected orchard.

Please advise if any of these approaches work. If I manage to try some I will post the results, but my lychee season has ended for the year. However, there are still the mangos.

I tried one of the high frequency sound devices which are supposed to scare mice etc and it worked for a few hours then they wised up.

Pity about that Doctor with nothing better to do than stake out Lychee orchards causing all that trouble. You'd think with the incurable diseases they carry, ever increasing numbers and no worthwhile purpose that open season would be declared. Not in this overurbanised country.

Further to the other post, find out the sort of range of frequencies the Bats use, as far as I am aware, the Bat can change his voice (frequency) when hunting with other Bats of the same ilk, so that each can fly, without interfering with the other(s)....

This means that you need to sweep the relevant frequencies quickly.

Also, the loudspeaker could be revolved to allow a wider area to be covered. This means slip rings for the power and maybe a short range radio to supply the revolving loudspeaker/amplifier with the frequencies needed......I would start with 60 RPM as a place to begin. Go to 120 if a higher speed is needed......that should not stress anything too much. Or go for 4 separate loudspeakers.......

I would start with around 50 watts of power as the Piezo speakers needed for the above human audible range speakers do not need a particularly high power to work effectively, nor can they take a lot of power either (I am assuming that as I could as a young man, hear some of the "squeaks" of the European Bats, that the frequencies needed are probably between 16 to 20 Khz., though I am not giving any guarantees you understand!!), but these frequencies are extrememly directional. (Which means that it either needs to revolve or many speakers, raised up around the height of the tree crowns to work best.....)

Hi Andy, and happy new year.

I think that you will find that all types of bats are a protected species within the EU, and that any type of interference with them will land you in court!!!

One example here in the UK was when someone was doing what you are thinking of doing, he was taken to court and fined heavily and warned that the next time he interfered with these animals he would be jailed!!!!!!!!

Spencer.

I was answering for our friend in India.....

I like bats and would not harm them, confusing their navigation radar should not do more than get them to leave, better than putting up thin nets and killing them!!.....

Andy,

Bats are fine, Flying Foxes are not. The OP is having fruit destruction problems. Flying Foxes look like bats but have entirely different behaviour. They destroy fruit orchards like locusts. In their dogma of protecting all pest species the greenies claim these vermin pollinate the forests, when in fact they destroy the blossoms.

They have bred up because food is plentiful in farmers' orchards, and protection has made it much worse.

Your real bats control insects and a large number of them live in caves and similar wheras Flying Foxes roost in trees and carry incurable diseases, Equine Morbili virus, Lyssa virus, Hendra virus. They are in plague proportions especially in such "enlightened" places as Tropical Australia. Handling damaged fruit, or working around it, is a high risk activity.

Hello Shanthasl,

I assume you have checked into any legalities but Scap is right - make sure whatever you do is acceptable in your area.

Just good stewardship.

Best of luck - I'm interested in this outcome - I'm trying to figure out how to get bats or birds to "come" to dinner and reduce the fly and mosquito problems out here in the plains.

Any ideas in the opposite realm would be appreciated!

I live on a pond, and I have very few mosquito's. There is a quite substantial bat population. I added a few of something like these, many years ago:

http://www.cleanairgardening.com/bathousthati.html

The "no vacancy" sign is always out.

I've also added some bird houses.

That's all you have to do, and it really makes a difference.

I used to live in semi desert at Mt Isa, Australia.

The river was either flooded or not running, there was no in between.

We had very few mosquitos because whenever the river stopped flowing, the pools left started shrinking due to the very high evaporation rate which forced the fish and frogs into a fairly small space.

Any mosquito larvae were eaten by the fish.

If you want to keep free of mosquitos, make sure your pond is well stocked with fish.

If they multiply too much you can always catch and eat the surplus.

Give them a place to sleep in during the day.....import a few breeding pairs.

Also, grow large bushes of Lavender around your house, Mosquitos do not like the smell, we have had major success in our garden on this score. It smells great!!

Lavender (many types around) are available for almost any climate.....

Cool - I guess Kevin Costner is right - if you build it they will come.

I appreciate it!

Once I build them, I wonder how to advertise "available, free" housing??

There are all kinds of animal sound recordings on the net: here's a page with a variety of bat noise that might be useful:

http://www.partnersinrhyme.com/soundfx/batsounds.shtml

good luck