Daphnia

[Insomniak]

My wildlife pond is just starting its second year and while I had millions of Daphnia last year, I could plainly see them when kneeling at the edge, so far this year I can see none.
When they "arrived" last year the water cleared within about 2 days.

The pond is in partial shade now, but through the winter months it gets no direct sunlight.
Water plants are starting to grow, putting up new shoots and I think the oxygenators are thriving in the deepest part of the pond.
Btw, it's a small garden pond, about 5ft x 5ft.

I *think* daphnia survive the winter, just wondering how long before they should reappear this year?

[Deb London]

All the "wild" ponds I've visited this year have been teeming with Daphnia etc. They are in my pond, but their numbers are still small. The water is still murky and there is a lot of animal activity. Not sure what is eating them (if anything) and why they are not so abundant. I expect their numbers to increase in the next few weeks.

[Richard Baber]

I've got more mosquito larvae than daphnia in my pond at the moment, which is a little unusual, and my water's murky too. It was hit hard by the cold this winter. Can't say I'm worried though, I'm sure all will balance out as usual and I expect yours will too.

BTW, you think your pond's small? Mine's tiny in comparison!

Richard

[Insomniak]

At the moment all I can see are the snails and the water slaters and there are lots of those.
I watched the pond today and the sun shone on about half of it in the afternoon, so I'm hoping that'll wake up the daphnia!

[Red Robin]

Last summer (my pond was created last June) I saw lots of Daphnia and also Mosquito larvae but then I didn't have newts which like to eat them. So far this year I've only seen one small 'cloud' of Daphnia and I think they got eaten. I have a few, not many, tadpoles too.

The water has always been very clear except when the bottom silt was disturbed by something for a couple of days. I exclusively use local chalk stream river water.

[Dogghound]

Isomniak where in Britain are you? Daphnia populations fluctuate depending on phytoplankton levels and water temperature (and predation). They are highly abundant and are likely to become re-established as soon as plankton and temperature increase in your pond. It may be that the shade is keeping the water cool as we are only in April. It can take a while for a shaded pond to regain a warm temperature especially when its been such a cold winter, even after several warm days the water may still be cool.

[Red Robin]

How do Daphnia arrive in a pond? Are they the larvae of a species?

[Dogghound]

They usually disperse through pond weed, birds, invertebrates, some species use the wind (apparently), directly through water change etc. They are an actual animal and are not larvae. The are a type of freshwater zooplankton.

[Insomniak]

Originally Posted by Dogghound

Isomniak where in Britain are you? Daphnia populations fluctuate depending on phytoplankton levels and water temperature (and predation). They are highly abundant and are likely to become re-established as soon as plankton and temperature increase in your pond. It may be that the shade is keeping the water cool as we are only in April. It can take a while for a shaded pond to regain a warm temperature especially when its been such a cold winter, even after several warm days the water may still be cool.

Dogghound, I'm in Dublin, Ireland.
I was coming to the conclusion that the lack of direct sunlight to warm up the water was responsible, alright.
As far as I can remember I noticed huge numbers of Daphnia around the middle to end of June last year and that's when the pond was getting sunlight all day.
Although we've had very warm days lately, it's not sufficient to heat the water to any significant degree.
I shall just be patient and hope the pond doesn't get too cloudy in the meantime.
Thanks!

[Dogghound]

If the pond is cool and shaded and does not contain fish etc it should stay relatively clear. So although you may not have as many grazers like daphnia you probably wont get as much phytoplanton. If your struggling with water quality there are thincan be done to solve it.