I have 2 red ear sliders, gambiosa, comets, hyacinths (mostly dead now) and water lettuce in a kiddie pool pond. In the winter I noticed some crustacean looking things on the roots of the water hyacinths. When disturbed they would crawl deeper into the root, and curl up. They look like a cross between a brine shrimp and a flea, and get up to an eighth of an inch big. I didn't worry about them, because I thought the turtles, and/or fish would eat them. Now all of the hyacinths are dead and the crustaceans seem to be in the petals of the lettuce, just like an aphid infestation on roses. Are they bad for my plants and/or pond critters? There seem to be many more of them and much fewer plants. Thanks for any help. I live in Los Angeles area.

If they're swimming around and sort of like fleas, they may be water fleas which are daphnia. If so, they're harmless. But, you say they curled up? In that case, maybe scuds but they get bigger than 1/8 of an inch. No matter what they are, I would have thought the mosquito fish (Gambusia) would have eaten them. They are probably harmless. Plant pests aren't usually active swimmers. Aphids can't swim. If in the plants, they could be plant pests but I'm not sure which kind as they don't fit any I know. You could add more fish to see if they can eat more of whatever the small animals are. The mystery animals are probably no harm to your other animals but I'm not positive on the plants. Some small crustaceans may nibble on plants if there's not enough other things to eat.

I think you are right, they are scuds, the smaller variety Hyallela. From surfing the 'net I understand they are a favorite food of trout, but I can't find any info as to whether the sliders, gambiosa or comets will eat them. If I don't get rid of a quite a few, I will be buying new plants soon, when last summer I had an abundance, and had to throw out some hyacinths and lettuce. :angry:

Thanks for your help!

The turtles, Gambusia, and goldfish should all eat some of the scuds. I'm not sure why they are not.

Robyn - thanks for your help! Monday night, after reading your suggestion about the scuds, although most of what I found on the 'net had to do with trout fly fishing, I came across this from http://www.ariverneversleeps.com/backissue...0/nature.shtml:
"Scuds can be found wherever there is decaying plant material, and dead animal life for them to scavenge upon. They are most active from dusk to dawn. During day they tend to seek out dark shadowy areas to rest. Even so, one can almost always find a few clambering and darting among the leaves and stems of submerged grasses, rushes, bur-reed, bulrushes, pond-lily, and pondweed species (Potamogeton spp) - especially if you stir up the bottom or lift a rock or log. Scuds typically live in shallow waters up to 7 m deep but can be found down to depths of 20 metres. Greatest numbers are found in the first 1 - 2 metres. Adults mate several times during the year. A female can produce up to 7 broods, and up to 20,000 offspring in a single year. Scuds hatch from eggs, the young being miniature versions of the adults. Growth is by series of moults. The entire life cycle is spent under water. Locomotion is by swimming. At rest the back is humped, while swimming the body is completely outstretched. Legs located along the abdominal segments propel the scuds through the water. Typically, a scud will swim up from 15 to 30 cm, then rest in a curled position, slowly settling downward, before darting forward again. It is this erratic movement that a flyfisher must mimic when retrieving a shrimp imitation, like Werner's Shrimp pattern. The retrieve should be relatively slow, and steady for up to 15 to 30 cm, and there should be frequent stops interspersed with quick short movements. When fishing a scud imitation during bright daylight concentrate on shadowy areas along weed beds, around rocks and submerged logs."

My problem started with seeing a few scuds on the hyacinth roots early winter, and thinking the turtles and/or fish would eat them. Our winter was rainy and chilly enough that I didn't venture outside much on the weekend to muck out the pond (I have no filter), the turtles/fish went into a partial hibernation and weren't eating much. I had read that the hyacinths and water lettuce would die back in the winter (even though SoCal is mild) so when the plants started looking scrappy, I thought it was natural. We had a couple of weeks of very sunny weather and thus the string algae was in full bloom. Lots of plant material for those nasty scuds. It's funny how seeing maybe 5-10 in the hyacinth roots is interesting, but seeing 100+ on a tiny brussel-sprout sized watter lettuce really grosses you out! Last night at 11pm I was swishing my plants and blasting them with water to shake as many off as I could. I transferred what was left of the plants into (hopefully) clearer water. This morning at 6am I did the same thing and I'm happy to report that this evening there were much fewer nasties on the plants. Hopefully my brussel sprouts will grow back into full sized lettuces and I'll have hyacinth blooms late summer. Thanks again, Linda :)

I hope your plants recover. It's too bad you don't have any large pond or aquarium fish to eat all those scuds as "treats."