London (change)
Today 15°C / 9°C
Tomorrow 16°C / 10°C
7 messages
10/05/2013 at 17:22

Hi,

about three years ago in the autumn  I made a wildlife pond out of a bath tub and did everything I'd read you should do in terms of helpful plants, rocks etc but that winter was incredibly cold, down to at least -12c at which point I would imagine the entire pond froze. I never had the pleasure of seeing any life in the pond but when the pond thawed about a dozen swollen dead frogs floated to the top!

im now in a new garden and am very keen to have an area to encourage frogs And toads but am desperate not to be responsible for more frog genocide! Any help hugely appreciated in terms of creating a helpful wet area.

thanks 

harvey

10/05/2013 at 18:21

 How deep was the water Harvey? I assume it was buried in the ground or the frogs wouldn't be able to get it there.

Aim for a good depth of water in at least part of the pond, a couple of feet or so. People are successful with a lot less but the frogs need some under the ice space and water can freeze a foot thick some years. Also a bigger body of water maintains a more even temperature at both extremes of climate. A pond liner is better than a bath, you can grade the sides and run it into vegetation at the edges. But you need some hard surface round the pond so you can lie on your front and peer into the pond to see what's there

 

10/05/2013 at 18:37

And you need a good depth of mud in the bottom for the frogs to snuggle down into.

Was it an old cast iron bath - I imagine that it would've got very cold indeed.  As Nutcutlet says, you'll do much better with a pond liner, and the pond should be roundish in shape, rather than long and thin like a cast iron bath, then there's a chance that the deep water middle won't freeze as quickly down at the bottom.

And a bog garden at the side of the pond will attract no end of wildlife - good luck

10/05/2013 at 19:09

Thanks very much! It was an old metal bath and it was buried to ground level, yes. So it was maybe 1 foot 2 or 2 inches throughout

so to improve I should use a liner and dig deeper in part. I would love to do this and may well do BUT unlike my big old allotment this is now my small back garden to my terraced house and my partner will need some convincing to let me dig a large pond! So to explore an alternative, If a large pond were ruled out do you think I'd be attracting much just with some kind of small trays and bowls of water along with lots of rotten leaves, rotting logs, pots etc etc maybe good for toads but not frogs? 

thanks again!

10/05/2013 at 19:19

I have just been listening to a previous edition of Gardener's Question Time all about this. The problem with thick ice forming is that noxious gases are trapped and the frogs die because of that. The best way to prevent this is to float a tennis ball or football/beach ball depending on the size of the pond to prevent the ice from completely closing over, and to check it daily. Apparently cracking the ice after it has frozen can cause deadly vibrations to overwintering frogs, so the ice should be kept clear from the outset, where possible, and never use salt, boiling water or chemicals to clear it (apparently some have resorted to these ideas). Also, be sure to include lots of oxygenating plants such as hornwort, to help keep oxygen levels up and provide cover. When snow falls on top of ice, clear the snow off, to allow these oxygenators to carry on photosynthesising. Also, you could line even the bath and that would help to insulate. It is apparently not so much the depth of water, but the lack of air circulation that causes most deaths.

10/05/2013 at 19:27

I used to use a little block of polystyrene floated on the top of a previous small pond. I had to tie it to the side to stop it disappearing on windy days but it also had a hollowed out bit underneath so it meant there was always an air pocket. (If you can imagine something like a small shoe box with an indent a small ball would makeon one face that's the general idea) Worked a treat. I found the 'ball' ineffective as it just got frozen in place. Boiling water etc not good as you say Pipstrelle!

13/05/2013 at 23:36

Google Germaine Greer's recent article in the Telegraph about National Frog Week, it's very interesting and could be really helpful.

email image
7 messages