# General Topics > General Discussion & News >  Garden Frog In frozen pond

## Andy

Hi, I have a small garden pond and this winter has been bad and today it froze the pond over badly, Now having supported my frog and toad community for over 7 years I now have the suprise of finding a frog still in it. He was struggling under the ice, so I broke it and let him breath i asume.  Now does anyone here have some advice as to what to do? do you have any tips to stop the pond or a part freezing over? Personaly I want to bring the little chap into the house but the wife says no way :Frown: 

Andy :Frog Smile:

----------


## John

Generally it's a bad idea to break the ice on the pond.  The pond still gets air exchange.  Common frogs (_Rana temporaria_) often hibernate in the mud at the bottom of ponds, even when the pond freezes over.

If you want to try and keep the pond somewhat ice-free, float a football or something in it (soccer ball to Americans).

----------


## tess

Can you explain how this works - I'm concerned now that I'm doing the wrong thing as I have been clearing the ice from the pond. Last year it was the first winter of our pond on the allotment and I didn't clear it and had the hideous experience of going up once the weather warmed up and finding 6 dead frogs floating on the surface of the pond. This year I've been up and cleared the ice several times - previously there was no evidence of the frogs, but today the ice was 2 1/2 inches thick and as I removed it two frogs swam about and some others were just under the surface and much more lethargic. Now I'm concerned I've done the wrong thing and disturbed them whilst they were hibernating. I've put things on the surface of the pond in the hope that they will stop or reduce freezing but the forecast is for seriously below zero temperatures. 

Any more info or links would be great.

Thanks

----------


## BEETLE

I have often seen common frogs moving around under the ice on garden ponds, I have even known them to spawn before all the ice has melted. Ice forms on the surface of ponds because water is at its greatest density at about 4 degrees C. One of the dangers of removing ice is that unless you replace the water the pond gets shallower increasing the risk of freezing the water to the bottom, killing the frogs.
I have had frogs die in a frozen over garden pond, there was a lot of spruce needles in the pond and I think that as they decayed the either took out too much of the oxygen, or judging from the smell, produced hydrogen sulphide.
After this I used to put a ball on the surface to try to keep a hole open and when this failed I would use some *warm* water to melt a hole every few days just to allow some gas exchange, I was never certain it helped but it did seem to stop the frogs dying. Frogs have hibernated in ponds for a long time in this country without human help and I guess they are pretty good at it.

----------


## John

When the ice forms on a pond, it actually helps to insulate the water of the pond from the extreme temperatures above the ice/at ground level.  When you break it you remove this insulation suddenly and the pond's overall temperature will drop, relatively speaking, rather sharply.  For a small pond this can help kill hibernating frogs in and of itself, and shock any other animal life in there too.  The effects are more pronounced on small ponds.  If you want to know more about this, search for the words thermocline and ponds.

Assuming you break the ice, any frogs "freed" are then exposed to the sub-zero temperatures your ice was protecting them from.  British frogs don't have any protection against freezing, so you could be doing more harm than good.

Regarding the frogs under the ice, think about it - if they were suffocating don't you think you'd already be finding bodies?  Another point is that severe winters kill frogs.  Fact of life.  This either occurs because of prolonged freezing conditions (British frogs simply can't withstand conditions like this so huge numbers die each winter), or because the frogs didn't build up the reserves needed to last the winter without food.  

The frogs that hibernate in a pond are taking a measured risk of dying during the winter in the hope that (a) they are in a safe environment with fewer predators and (b) they won't have to migrate to their breeding pond in the spring time, thus potentially saving energy for breeding and getting first pick of mates.

----------


## tess

Hi there,

Thanks for your responses. i think part of the problem is that our pond is near some trees so no matter what I do I can't keep all the decaying vegetation out so it's probably this combined with the freezing which creates problems. I think I need to make sure there's a hole in the ice to ensure there's enough oxygen in that water for the frogs but not disturb things so much and risk the water temperature dropping. I have put some plastic balls and objects floating on the water so it should be easier to remove these to enable oxygen to get in. the pond it pretty deep and there's a good layer of mud in the bottom so hopefully they'll be Ok down there and the water level shouldn't be a problem.

To be fair, despite last year's fatalities there was no shortage of spawn in the pond this spring and we seem to have quite a healthy population, but I was hoping to avoid the grizzly task of fishing out the bodies this last yea.

----------


## John

You're right about the decaying vegetation - too much can cause problems as it breaks down and with little surface area for gaseous exchange.

----------


## zakaspfc

Have a look at the product called the "Pond Breather"

Pond Heaters & De-icers

Itll keep a hole in your ice for gas exchange, without causing huge temperature swings (according to their website).

----------


## antoinetteolesen

> When the ice forms on a pond, it actually helps to insulate the water of the pond from the extreme temperatures above the ice/at ground level.  When you break it you remove this insulation suddenly and the pond's overall temperature will drop, relatively speaking, rather sharply.  For a small pond this can help kill hibernating frogs in and of itself, and shock any other animal life in there too.  The effects are more pronounced on small ponds.  If you want to know more about this, search for the words thermocline and ponds.
> 
> Assuming you break the ice, any frogs "freed" are then exposed to the sub-zero temperatures your ice was protecting them from.  British frogs don't have any protection against freezing, so you could be doing more harm than good.
> 
> Regarding the frogs under the ice, think about it - if they were suffocating don't you think you'd already be finding bodies?  Another point is that severe winters kill frogs.  Fact of life.  This either occurs because of prolonged freezing conditions (British frogs simply can't withstand conditions like this so huge numbers die each winter), or because the frogs didn't build up the reserves needed to last the winter without food.  
> 
> The frogs that hibernate in a pond are taking a measured risk of dying during the winter in the hope that (a) they are in a safe environment with fewer predators and (b) they won't have to migrate to their breeding pond in the spring time, thus potentially saving energy for breeding and getting first pick of mates.


John, I have a cement garden pond (6' x 6') just under 2' deep. It is now frozen over and there were quite a few leaves in it as I didn't know about the vegetation problem. I have 4 bullfrogs in there (about 6" long) and wonder if I should break a hole in the ice? Also what do you think about the "Pond Breather" or any type of pond heater? Thanks, Antoinette

----------


## John

Not knowing where you live exactly makes it hard to answer that.  2 feet deep is very shallow for a pond - I would not be surprised if that was prone to freezing solid in most temperate countries.  I would try the floating ball solution first to see if that helps (doesn't work on ponds that have thick ice on them though).  

Looking at those products from a nature pond point of view, it really depends on how much they heat the water.  However it seems like they only keep a small area ice-free, and if this is the case I'm all in favour of them but I advise you trial one before leaving it in there permanently.

----------


## Andy

Thanks

----------


## antoinetteolesen

> Not knowing where you live exactly makes it hard to answer that.  2 feet deep is very shallow for a pond - I would not be surprised if that was prone to freezing solid in most temperate countries.  I would try the floating ball solution first to see if that helps (doesn't work on ponds that have thick ice on them though).  
> 
> Looking at those products from a nature pond point of view, it really depends on how much they heat the water.  However it seems like they only keep a small area ice-free, and if this is the case I'm all in favour of them but I advise you trial one before leaving it in there permanently.


Hi John, I live in Nashville TN., we only get a tiny amount of snow once in a great while. It has been a particularly cold winter (for us anyway... 10 degrees or so at the coldest) without warm days in between. Now it is expected to snow tonight and stay cold for a while. The top of the pond is frozen solid. I've never seen it freeze all of the way. But it's never stayed so cold so long.  I'm wondering if I should go buy a heater. But I don't want to cause problems from that either. One more thing, there is a fountain that is flowing into the center of the pond that has a filter. I leave it on all year. Any thoughts or suggestions would be appreciated.  Thanks! Antoinette

----------


## BEETLE

The fountain question is a difficult one, because water reaches its maximum density above its freezing point, if the pump is mixing the water round it could make the bottom of the pond, were presumably the frogs are, colder and may increase the chances of it freezing through. But most pumps also put a little heat into the water and if it is keeping part of the surface ice free it might be good (I couldn't tell if that is what you ment). I would check the temp, at the bottom with the pump on and off. My bet is it would be warmer with it off.

----------


## RHD

I have a half barrel water feature with a couple of water lilies and a fountain. The half barrel is about 3' wide by 18 to 20 " deep. In this three large frogs have decided to live. At first I couldn't figure out how they got in but then one day I saw one hop out and then a little while later, hop back up the side again from the grass. Those guys really can jump. 
Last spring, after much croaking and splashing about, there were two blobs of spawn and they all hatched but very few tadpoles grew legs and made it out. I think maybe the big frogs ate them as I never saw any corpses.

With the unusually cold weather for Central London, UK, I have been worried the big frogs are running short of oxygen in such a small amount of water as I have seen one up at the surface trapped under the ice which is quite thick. This is unusual behaviour as they don't usually surface at this time they hibernate at the bottom and I don't see them for another month or so. I leave the little fountain off over winter it is not up to prolonged use  so I only have it on a few hours a day when I'm in the garden in the summer.

I melted a couple of holes five or six inches across in the ice with hot water (keeping it well away from the frog) as I have heard breaking the ice by impact can cause shock waves which can kill fish. I'm glad now I did it this way after reading what you said about the ice keeping the temperature up. 

Now I have made a sort of floating device out of tin foil and a tea light. The idea is that the tea light heats up the tin foil and melts a hole in the ice hopefully leaving a small hole to allow some oxygen in but 95% at least of the surface will remain frozen. I hope this strikes a medium between the ice keeping the frogs warm and the hole giving them enough oxygen. I'll let you know how it goes.

----------


## Will

hi guys, I am new here, found the site when searching for advice on whether or not to break pond ice.

I would say to be safe DO make a hole in it. I've just found 15 dead frogs (and a dead goldfish) in my tiny (smaller than a bathtub) pond. It has always been very popular with frogs, but I never imagined there were that many hibernating in there.
It could have been the cold that killed them, rather than lack of oxygen, as such a small body of water loses heat more rapidly than a larger pond. However, I am tending towards thinking it was lack of oxygen resulting from the fact there were so many of them, as well as two fish, in such a small space. There is also a fair bit of decaying vegetation in the pond, which I hear eats up oxygen.

If you have a similar situation in your pond - crowded, fish as well as frogs, decaying vegetation or silt at the bottom, lack of oxygen generating underwater foliage - then definitely melt or gently break the ice.

I am pretty sad about my poor frogs  :Frown:  I hope the species as a whole hasn't suffered to greatly with this cold winter here in the UK

----------


## RHD

The tin foil float with a tea light candle in it worked well. Even after the candle went out the wind blew the foil about and kept the hole open. No dead frogs to report so far.

----------


## John

RHD's idea is a good one.  Glad to hear it works.  

Will, regarding your frogs dying under the ice, how big is the pond?  Something to take into account is the size of the pond versus how many frogs are in there.  Obviously the smaller the pond versus the higher the number of frogs, the harder it will be for them to get a sufficient share of the dissolved oxygen before it's used up/isn't replenished fast enough by gaseous exchange.  

In the UK this year it has been a record poor winter and this has caused a lot of severely frozen ponds, and many ponds have frozen solid throughout the country.  It may sound harsh of me to say it, but it is natural for a significant portion of the frog population to die off under such rare conditions.  They will certainly bounce back.  Since most of Common Frog population, all of the Common Toad population and most newts don't spend their winter in the pond, they obviously won't drown in ponds, but they will also suffer losses because the average depth of their refuges will likely not be sufficient to escape the effects of the severe winter.  So all in all, not a bright year ahead for British amphibians.  Take heart though- the populations will recover, though it may take a few years.  I suspect the Common Toad will fair far better than the Common Frog this year, as should the newts.

----------


## mcdebs

I live in the UK - unfortunately we had to fish out over a dozen dead frogs from our pond today although the only fish we have in there is very much alive.  Just hope enough frogs survived to spawn when the warmer weather arrives (if it ever does)

Debbie

----------


## Andy

Well funny you reply to this, Last night one large toad came out for a nosey around the pond from under the mess of leaves, I was amazed it survived the winter. Seriously it was the worst with 2 Inches of frozen ice on top and it was -12 up here in Scotland and sub zero for weeks. Only thing I changed this year was loads of plants and that oxegenating plant type weed. I necer cracked the Ice as i risked splitting the liner as well as stressing what lay under  :Smile:  I wish i had a pic. I did a video clip on you tube of thelast winter and the pond and its not a big one :0
YouTube - Frozen pond with frog in winter
Bye 
Andy

----------


## Juliet

Hello! This is my first time here and I would be very grateful for any help and advice I can get from you fellow frog lovers! I have two small garden ponds, each with very good natural eco systems. I have frogs in each pond and each year when they have iced over I've broken some of the ice to allow oxygen through and there hasn't been a death toll when it melts. However last year when I was away for a week in those freezing temperatures, the ponds iced over and when the water melted, I had three dead frogs. We've had a very mild winter here in the UK and last weekend I noticed my frogs had started mating. They were all very close to the surface. Three days ago the freezing temperatures set in and each morning and evening I've been breaking and clearing away two 1ft x 1ft sectons of ice in each pond to allow oxygen through (I'm currenlty melting that ice by the fire to pour back in so I don't lower the water level too much). The frogs have been visible, right under the ice and up against it. As soon as I cleared the ice, they came to the surface and stayed there for quite a while. I have also put balls, flower pots and some wood in the pond to see if that would help ...but I don't think it is . Having read this forum I poured some hot water in a few places to create a few 'air vents'...but in doing so , I hope I don't burn the frogs! (Oh, it is a dilema!). I've read all the articles here, and I'm not sure if I am doing the right thing. If they weren't mating and were in the mud hibernating, I don't think that would be so bad, but they're not. I want to keep the ice as insulation but given last years deaths I feel that I should remove some of it... but then in doing so, I don't want to kill them by lowering the water temperature. I will try the night light trick aswell ... but if anyone can offer advice, I would be SO grateful. Thank you!

----------

