What on earth is this...?

[John Roberts]

Hello to everyone on the forum from a Newbie

I've noticed something squirming around in my pond today, which I have never seen before. There are a number of them, varying in length from around an inch or so to around three inches, including the 'tail.'

I can best describe them as a globby mess, with some black blobs and wavy white lines squirming around inside a jelly-like mass. Behind each jelly mass follows a relatively very long and wire-like 'tail.'

I have always had a number of frogs in my pond but curiously none this year so I wonder if they used to eat whatever these are, which could explain why I have never seen them before.

Sorry about the rather blurred photograph, if a clearer picture is required I can try and capture one but hopefully this might be enough to aid identification.

Many thanks in advance - John

Link to a photograph of the weird mobile globby mess

[Deb London]

It looks like a Rat-tailed Maggot, the larval stage of a species of hoverfly.

I imagine frogs/tadpoles might eat them.

PS Welcome to WAB

[John Roberts]

Thanks for the reply Deb, and also for the welcome

I've just Googled it, and it looks suspiciously like what I have in my pond. I'm just curious as to why these larvae appear to live in "stagnant oxygen-deprived water" because I have oxygenating plants as well as a capable pump running 24/7. I've never had problems with water before

I also don't have any frogs this year but an abundance of mosquito larva, which again suggests stagnant water

[Deb London]

I would have thought the oxygenators and pump would mean plenty of oxygen to be honest.

There are always plenty of forum members ready to diagnose any potential pond problems if you are worried John. Especially if you post a picture.

[John Roberts]

No, it's something I don't understand either. The only thing I have done differently this year is to use Barley Straw on recommendation of my local 'pond shop' to cut down on string-like algae, as opposed to using various proprietory chemicals as I have done in the past.

I never had a problem with stagnant water but had an abundance of algae, now it appears to be the other way around!

[Deb London]

Barley straw is fairly benign. I used it and it had no effect on anything, blanket weed included.

Lots of midges this year and not last (at the same time of year, give or take) suggests that you have a reduced number of one/more predators. I say this because midges etc really do lay and complete their life cycle in almost any body of water, regardless of quality.

I have three ponds and only the one with fish has none. In another there is a type of leech that polishes them off when its numbers have increased sufficiently (numbers of larvae in this pond cycle up and down). The third (new puddle really) is teeming with these creatures.

Mind you, they are all supporting life. I'm not concerned about the levels of these larvae.

Tip - go out at night with a torch. You will see the creatures that live there more easily. You might discover for example, that this year you have newts instead of frogs (they don't tend to breed in the same ponds). Newts breed a little later than frogs. Just a suggestion.

[John Roberts]

OK - thanks for that tip, I'll have a look after dark and see what's happening in there, I might also have a trip to my local pond shop and see what they can suggest

Many thanks!

[King Edward]

I normally see these in water where there's a lot of rotting plant material, e.g. in water-filled plant trays that have become clogged with fallen leaves. They can tolerate very poor water quality due to the long breathing tube which reaches up to the surface, although I doubt they actually require foul water. I imagine newts and fish might eat them - do you have fish in the pond?

[John Roberts]

There's very little in the way of rotting vegetation in the pond, although the water does seem quite green and cloudy now, in fact I can't even see the pump anymore even though the pond is only about 20" deep.

There are no fish in the pond, that's something I'm not overly interested in, so it's more of an ornamental feature although the frogs have moved in over the last few years.

I may have to resort to the good old 'Greenaway' in addition to the Barley Straw

[King Edward]

What's the pump for? Do you have a fountain/spout type setup, or just a filter. If the latter, you should be able to maintain good water quality without one (and without various additives as well).