Bats Bats Bats

[AMc]

As I've mentioned before we have around 150 pipistrelle bats that breed in our roof each summer.
Apart from making the loft pong a bit of bat wee and leaving sticky droppings on the roof of the vinery they are welcome to use the loft.
Last year we had no visitors so I thought that the renovation had finally sealed the remaining holes between the (human) house and the (bat) loft.
The major downside is we have to close the windows and doors towards dusk to stop them from finding their way into the house instead of entering the loft under the edge of the roof.

Unfortunately the young bats are now taking to the air and as with previous years they are finding their way into the house - We had to deal with 3 on Saturday night and 1 on Monday. It's a time consuming process - closing doors, opening curtains and windows so they can find their way out then checking behind all the furniture to make sure they're gone - it usually coincides with our bed time when I'm least in the mood for dealing with a confused flying animal in my bedroom.

I was particularly perturbed to see them starting to leave the roost at 4.30pm on Sunday afternoon in bright hot sun - I don't know if the roost was overheating, they were really hungry or they routinely leave before sunset and I'm not normally about to see. It simply isn't practical to seal the house up from that time of day, its uncomfortable enough sleeping with closed windows in the current heat but shutting the ventilation in the vinery before dusk will cause the house to superheat.

We had the local bat protection volunteer around a couple of times in the last 3 years but he can't find any way that they're getting in though the house so I'm sure they're arriving through the roof windows in the vinery, windows in the house or through open doors. I'm still hoping that they all came in on Saturday evening when we were in the garden until 8ish and the door was left open.

I was investigating if I could use an ultrasonic pest repeller to set up a 'no fly zone' in the vinery which would keep them outside and let us keep the door open but it looks (from the UK based sites) that this could be considered to be interfering with the roost and as that's a criminal offence I don't think I can do it. Just to reiterate I'm happy for them to stay in the loft, but I need to keep them out of the house and get some air in in the early evening.
http://www.bats.org.uk/pages/living_with_bats.html

Has anyone got any bright ideas on polite ways I can keep them from flying into the house?
Anyone know where I can get a butchers shop curtain that will be 'visible' to a bat's echolocation and isn't painfully ugly - the metal ones seem to be over £100?

 

[Feltwell]

Fantastic to have the bats, but you have my sympathy on them coming into the house - that is a right pain. A much, much more minor level but we seemed to be on a flightpath for bees last summer - I was forever rescuing them after they'd come in through our lounge window. It hadn't happened in previous years which was odd. I also used to spend ages rescuing baby sparrows from the garage, as they had managed to get in there from their nest somehow.

Bead curtains - I'd forgotten about those, they were everywhere in the '70's You only see them in Chinese takeaways now! Loads on Ebay (although some are pretty nasty) and it sounds like a good idea.

How about mesh over your windows? A simple temporary frame fixed internally or externally with some mesh stapled across it. Could you put mesh under your vinery roof windows?

And how about encouraging the bats towards a certain area? I was wondering if they are being attracted to your windows after dark by the insects that are attracted to the light from within. My parents put up a low powered exterior light on a fence opposite their lounge window at their last house, specifically to attract insects and hence bats. It was rather lovely to sit there in the evening and watch the bats swooping around.

 

[Penners]

Anyone know where I can get a butchers shop curtain that will be 'visible' to a bat's echolocation and isn't painfully ugly - the metal ones seem to be over £100?

I have no idea of the price, but have you considered a chain screen? As to the "painfully ugly", I'm afraid that's down to your own taste!

http://www.redwoodstripcurtains.co.uk/flyScreen.php

 

[Flyfisher]

Would it be practical to make the attic more accessible to the bats such that they don't feel the need to come into the house? I've no idea how this might be done but wonder if the bat experts could offer advice about such things. Or is the problem just with the young bats who perhaps have not yet got the hang of getting back into the attic?

 

[MattW]

My parents have bats roosting nearby. They fitted fly screens to the windows and doors so that they can be open for ventilation without allowing bugs from the near by marsh to enter this house. It has the fortuitous effect of also preventing the bats from entering also...

 

[AMc]

Fantastic to have the bats

A matter of opinion this morning - another young, stupid and tired bat in the bedroom last night - I had a total and complete sense of humour failure about this as I've had all the doors an windows closed since 5pm. It now knows a number of good old English names for an animal that's not wanted indoors. I caught it in a shoe box and released it near the entrance to the roost and it aint there now so I guess it went home. I'm still hoping it was a straggler from Saturday night as they're so small they can easily hide in the house.

They can't be attracted in by lights as the windows are all closed well before dusk or we turn on the lights and most of the windows have blackout lined curtains.
We have an outside light on the opposite side of the house which is on most of the evening (no street lights) and this is a hunting ground for them.

Screens on the roof windows aren't practical because the motors stick down into the room and move horizontally as they open/close.
We're resigned to closing the house windows at or before dusk but when it's still 27C in the vinery at 9pm it isn't ideal.

I don't think they're coming into the house trying to get into the roost, the timing suggests they're off for the night. When I've watched them closely they tend to leave the roots and head for the country - the only time I've seen them come back is when I was still up at 3am and the sun was starting to come back up.
I think the trapped ones are just young and inexperienced I don't think there is an access problem.
We did get one adult follow my partner into the vinery before they gave birth - it did a couple of circuits and then flew out of the door I'd reopened. I guess you don't get to be almost a year old as a bat without learning how to fly out of a door as well as in.

Finally the fella from the Bat's protection has been twice in previous years. He is a lovely bloke but in all honesty I think he was much more excited about the idea of >100 Pips just up the road from him than he was about my problems with them in the house. He couldn't see any obvious routes in and his advice was ... close the windows before dusk

My BIG worry about the whole thing is the roost is directly above my 7 year old daughters roof. She's got used to them "twittering & tw&ttering" above her head and above her bathroom - but I suspect she will have an entirely different reaction if she discovers one silently lapping her room towards her head after dark. It's a sight that never fails to freak me out so I can only imagine her reaction.

Thanks for the suggestions - off to hunt for a metal chain curtain that doesn't make me want to be ill on the keyboard then see if my partner can stand the sight.
The idea of mesh screens on the windows isn't appealing - may be I'll have to look into that too.

 

[AMc]

Just found a bat corpse in the "guest" bathroom Not sure how long it had been there as we don't use it unless ... there are guests.

By the looks of the cobwebs on the paws/claws(?) it had been trying to clamber back into the loft via the extractor fan vent...or perhaps it had come out of the extractor. Not sure if that indicates it couldn't get in there or that having successfully found its way through the duct it couldn't get back and got stuck in the bathroom.
I guess I'll have to check the hoses when they're gone for the winter.

Grim

 

[Penners]

Just found a bat corpse in the "guest" bathroom.... it had been trying to clamber back into the loft via the extractor fan vent

Honestly - bats! They're absolutely... er.....