Baby Frogs Dying

[ymm]

Hi all, wonder if anyone can give me some advice please?

We've had loads of pleasure this year watching lots of tadpoles develop into tiny frogs and seeing may of them hopping in and out of the pond. We counted at least 20 baby frogs just last week, (plus about 20 tadpoles with legs & tail that still need to complete their develpoment) and they seemed to have been thriving in the pond. Today, however, when I went to check on them, there were 2 baby frogs dead and floating in the pond. Nothing has changed in the pond as far as we're aware and there are still a few tadpoles swimming around, but I can't see any actual frogs any more. The dead ones seem to have a blue/grey colour to them, but I don't know if this is normal once they die.

If anyone could help, I would be really grateful.

Regards,
Yvonne

[aland]

Hi is it possible the pond as got contaminated or as any blue type [alggey] ? on it, our neighbors pond once had a problem with farm type effluent every thing died, my wife and i put a new bottom in it as it was seeping in from farm land, aland.

[aland]

I forgot to mention this warm weather can cause problems with still water, if this is the case you need to agitate the surface or oxygenate the water have a hose with a sprinkler on it for some time if poss, ponds need some shade, this is why fish keepers use pumps to circulate the water, our pond has seventy fish some large and we have three pumps to brake up the surface also large trees surround it, other wise our fish would certainly die, any disturbance of the surface you can do will help, aland.

[Bullseye]

Could be Dragonfly nymphs,they suck the juice out of them.

[ymm]

Hi Aland & Bullseye,

Thanks for your replies.

I'm pretty sure the pond hasn't been contaminated, but I must admit, we haven't used the pump much lately, although I usually top up the water with the hose every few days, so maybe this is why. Now they're all much bigger, I'll keep the pump/fountain going, (I was worried about the little tadpoles being sucked into the pump!).

We also have loads of dragonflies around too, which is great, but I never thought about their nymphs doing any damage.

Hopefully, we won't find any more dead frogs now, but really appreciate your advice.

Cheers, Yvonne

[aland]

Hello, it probably is down to warm weather i have had to call out the environmental people to a gravel pit near warwick one year it became covered in a blue algey and chub were dieing they used a pump to oxygenate the water, i think it only happens in extremes of warm weather, aland.

[Paul mabbott]

Could be something toxic in the ground water but unlikely to be lack of oxygen - they should be lung-breathing at that stage, I think.
Do the dead ones have all their limbs? Cannibalism is a possibility.
Do they have enough food? At the limbed stage they will be switching to a carnivorous diet (although marmite sandwiches are acceptable).

[crazylilthing]

Yvonne, I used to keep frogs and toads for many years and reared them from egg stage onwards.

What aspect is your garden pond? (north, south, east or west facing) Unless it is very deep, it is possible that it will get very warm to hot if it is in direct sunlight and facing south to west. This will kill the frogs very easily.

The pond should ideally be partially to heavily shaded by plants (at least 50% shade) for the hottest part of the day in midsummer. There should also be shade areas around the pond, such as low-growing plants with broad leaves, flower pots (clay/terracotta) or similar.

The discoloration is a normal decay indicator.

The survival rate of froglets is very low, not surprisingly, given their tiny size, which makes them a very appealing snack, but you can give them a good start!

[Gill Catton]

My money is on predators like greater waterboatmen and dragonfly larvae. Where there is life there is death and really that is how it should be.

Amphibians breath air should should be able to cope relatively well with wamer water and lower oxygen levels, in addition if they have their legs they are able to leave a pond if the conditions become unsuitable and as they haven't I'd guess that they'be been eaten!

Tadpoles develop in the wild quite succesfully in everything from tyre rutts to disused swimming pools so are pretty resiliant to a wide variety of water conditions. If everything else is living happily in the pond then you can probably rule out contamination and a healthy aquatic ecosystem with predators and prey in!

[crazylilthing]

Originally Posted by Gill Catton

Amphibians breath air should should be able to cope relatively well with wamer water and lower oxygen levels, in addition if they have their legs they are able to leave a pond if the conditions become unsuitable and as they haven't I'd guess that they'be been eaten!

True, but I've noticed that some garden ponds have difficult exits for froglets. Even if they want to escape the warm water, they can't because there's nothing for them to help them get out.

Paradoxically, some tiny froglets may be able to clamber up near-vertical surfaces when there's a high surface tension, like wet glass, but not sheer-sided pond walls.

[Gill Catton]

I think there is a risk with surfaces they can get stuck to like paving slabs or concrete but if they can get out they will.

[ymm]

Thanks so much all of you for your advice.

I'm pleased to say we haven't found any more dead frogs and most of them seemed to have left the pond now, just spot the odd one or two now & again.

We inherited our pond when we moved here and the water level always goes down to about 2-3 inches below ground level, (think we have a leak in the liner), but we've made it as frog friendly as possible, by building 'bridges' from rocks and wood and keeping the pond well stocked with plants for them to shelter in. We've also made a 'frog house' out of old clay pots in the shady plants around the edge, so hopefully they'll enjoy their habitat.

Like you said, I think I just have to accept it's predators and that's nature of course. I'm just glad, from what you've all said, that it wasn't any nasty disease or anything.

Once again, many thanks.
Yvonne

[Gill Catton]

Originally Posted by ymm

Thanks so much all of you for your advice.

I'm pleased to say we haven't found any more dead frogs and most of them seemed to have left the pond now, just spot the odd one or two now & again.

We inherited our pond when we moved here and the water level always goes down to about 2-3 inches below ground level, (think we have a leak in the liner), but we've made it as frog friendly as possible, by building 'bridges' from rocks and wood and keeping the pond well stocked with plants for them to shelter in. We've also made a 'frog house' out of old clay pots in the shady plants around the edge, so hopefully they'll enjoy their habitat.

Like you said, I think I just have to accept it's predators and that's nature of course. I'm just glad, from what you've all said, that it wasn't any nasty disease or anything.

Once again, many thanks.
Yvonne

Predators as beautiful as dragonflies are well worth a few tadpoles/ baby frogs in my book

[Kayleigh]

We had a problem one year with waterboatmen killing tiny toads..They would wait for the toads to run the gauntlet from a water lily to the bank then attack and kill the toads but not eat them..
So we removed the waterboatmen and the rest of the toads survived..
I would not normally intervene if they were being killed for food but they were not..

[Gill Catton]

Originally Posted by Kayleigh

We had a problem one year with waterboatmen killing tiny toads..They would wait for the toads to run the gauntlet from a water lily to the bank then attack and kill the toads but not eat them..
So we removed the waterboatmen and the rest of the toads survived..
I would not normally intervene if they were being killed for food but they were not..

They were being killed for food though... Why else would the water boatmen do this? They don't consume the outside of a prey item them suck the juices from inside with a piercing mouthpart which is not obvious to our eyes. Leaving a shell that would look like a normal body to our eyes.

Its a semi-natural ecosystem an sould be encouraged in all of its forms surely.

[southlonder]

Originally Posted by Bullseye

Could be Dragonfly nymphs,they suck the juice out of them.

Do they? I thought they ate solid food

[Kayleigh]

Originally Posted by Gill Catton

They were being killed for food though... Why else would the water boatmen do this? They don't consume the outside of a prey item them suck the juices from inside with a piercing mouthpart which is not obvious to our eyes. Leaving a shell that would look like a normal body to our eyes.

Its a semi-natural ecosystem an sould be encouraged in all of its forms surely.

No Gill, I watched a waterboatman sense the ripple on the water and target the tiny toads as they were leaving the pond maybe the taste of the toads put them off eating them but left one dead and went straight to its next victim and so on killing a considerable number when they were leaving the pond..
This year there is too much weed and less open water so the toads will be safe as they leave the pond..

[Gill Catton]

Originally Posted by Kayleigh

No Gill, I watched a waterboatman sense the ripple on the water and target the tiny toads as they were leaving the pond maybe the taste of the toads put them off eating them but left one dead and went straight to its next victim and so on killing a considerable number when they were leaving the pond..
This year there is too much weed and less open water so the toads will be safe as they leave the pond..

but surely it was the insertion of the needle-like mouth parts that killed the toads its their only 'weapon'?

I mean its fine obviously its your pond and its up to you how you manage it of course it is, I just think they probably were eating the toads - just maybe a little bit of each - there's probably not a great deal of juicy stuff inside a tiny toad.

[acherontia]

Going back to the original post it sounds like a lot is being done for the frogs which is commendable.
There'll always be plenty of non survivers which is why the frogs produce so much spawn.

We had probably 2000+ tadpoles - some are still in the 'tadder' stage and 100s of 'froglets' are now knocking about all over the garden. The blackbirds love a bit of tasty tadpole and frog but our favourite frog feaster at the moment is a young hedgehog who will probably survive because of the extra food that's there.

Then - if I mow the lawn I have to shut off about how many will be cut down before their prime - although (soft s.d me) I have been setting the blade a bit higher

I'm sure all will be well if you've read up on how to make a pond wildlife friendly and followed some of the advice here.

Acherontia

[ymm]

Hi all,
Thers's so much good information here, I've learnt loads, so thanks for all that.
The one thing that really surprised me was that Waterboatmen are such a threat. We've got literally hundreds in our pond, (or maybe Backswimmers, I can't really tell the difference). My dilemma now is, do I leave nature to sort itself out or do I remove some of them from the pond to give the tadpoles and frogs a fighting chance? What do you all think?
Thanks, Yvonne

[Kayleigh]

Originally Posted by ymm

Hi all,
Thers's so much good information here, I've learnt loads, so thanks for all that.
The one thing that really surprised me was that Waterboatmen are such a threat. We've got literally hundreds in our pond, (or maybe Backswimmers, I can't really tell the difference). My dilemma now is, do I leave nature to sort itself out or do I remove some of them from the pond to give the tadpoles and frogs a fighting chance? What do you all think?
Thanks, Yvonne

You have to make that decision....I know what I would do..

[Gill Catton]

Originally Posted by ymm

Hi all,
Thers's so much good information here, I've learnt loads, so thanks for all that.
The one thing that really surprised me was that Waterboatmen are such a threat. We've got literally hundreds in our pond, (or maybe Backswimmers, I can't really tell the difference). My dilemma now is, do I leave nature to sort itself out or do I remove some of them from the pond to give the tadpoles and frogs a fighting chance? What do you all think?
Thanks, Yvonne

lesser waterboatmen swin the right way up and are vegetarian so don't confuse those.

Backswimmers or greater waterboatmen will take tadpoles and baby toads. However. This is one of the many reasons that toads and frogs have so so many tadpoles because almost every omnivorous or carnivorous animal that can eat them, will. Greater waterboamen may not be pretty, but they are pretty fascinating they way they seem to cling to the top of the water and carry air on their backs and are part of the natural aquatic environment. Their offspring will fall prey to other invertebrates or perhaps even to frogs and toads and as they fly the adults are food for bats and birds tooso are part of the whole cycle .

They also won't suceed in eating all the babies. I have seen artificial ponds with no vegetation and seemingly nothing but great crested newts and loads of these greater water boatmen. I did see the greater waterboatmen taking newt tadpole after newt tadpole but there were still almost hundreds of newts in all life stages illustrating their lack of impact.

I hope you leave them, but if you do feel you have to remove them don't handle them as they can give a nasty bite. Not that any have ever bitten me. Infact they use to turn up in mum and dad's old pool from time to time and when I was little I used to follow them around underwater with my goggles on!

[Scubapauly]

Some of this is just survival of the fittest. I fished 3 dead frogs out of my very small pond the other evening. But then saw another 3 alive and kicking. So I put it down to the first 3 being too stupid to find there way out (hey it makes me feel better).