38 replies to this topic

[gerald]

Auban wrote:  "The thing I find interesting to think about is that drainage ditches are entirely man made structures. They are providing environments for all kinds of little critters to live in that may otherwise have no other suitable habitat later on down the road."

 

In most cases, a drainage ditch is a man-made replacement for a natural drainageway (stream or wetland).  These sites presumably had all sorts of native critters for millenia before they were converted into ditches.  Relatively few ditches are "entirely man made" (in places that were not waters or wetlands prior to ditching).  This is a hot button in the arguments for and against regulating construction impacts to "ditches" to protect water quality.

[Auban]

I wouldn't argue that the environment was there for these critters before we obliterated them and constrained them to mere roadside ditches. I'm mostly interested in knowing what happens to those tiny communities. I would think that any affects that we can produce on them would be much more immediately visible than affects we have on larger aquatic ecosystems.

To me, they seem like an opportunity to study the effects of farm runoff, pollution, etc. They aren't exactly large... Just a little bit of change would probably be easily and quickly observable.

Anyway, to dispel any doubts that I may have clam shrimp, here is a pic of one of the little clams climbing up the side of its tank: https://vgy.me/r6Csvr.jpg

[gerald]

Looks just like a booger that my kid flicked on a tank once.  Re ditches, yup, just one uncaptured oil change, radiator hose failure, or car wreck could pretty much render a ditch uninhabitable for gill-breathing critters for a year or more.  And in places with public water systems, hydrant flushing poisons them with chlorine a couple times a year (and the headwater creeks they flow into).  Chlorine is gone much quicker than motor oil or antifreeze, but the frequency of  impacts doesn't allow much chance for recolonization.

[mattknepley]

Booger Clam does seem to be an accurate moniker!

[Auban]

So, after observing these guys for a while, I have found something interesting...

They have a tendency to hang out in floating clumps of algae. I am not sure if they were already in the algae and the oxygen bubbles caused the algae mat to lift them to the surface or if they crawled their way up the sides of the tank. But given that I found 23 of the little clams in a single clump of floating algae, I suspect that they seek the floating clumps out.


Someone with more knowledge than I about these things(ahem... Gerald) told me that they do not persist long in the presence of mosquito fish. If they seek the highest level of their environment, this may help explain why. Surface feeders would obviously have more impact on them if they are spending their time near the surface of the water. While they cannot eat the adult clams, they may be able to eat the babies.

I need to get some mosquito fish and test this idea...

[mattknepley]

Knowing the enthusiasm many fishes have for baby snails, I have no doubt surface feeders could find those clams palatable. I don't doubt they (those clams) may look for/ prefer floating algae for a home. Lots of sea critters like to live in the floating forest of the Saragasso Sea, why couldn't freshies find a reason for that type of lifestyle to work for them?

[gerald]

The fingernail clams in my tubs outside (without fish) seem to stay on the bottom in the sediment.  I've never noticed them climbing sides or in floating algae or plants.  I guess different kinds have different behaviors.  I do find some in flowing streams (often in moss mats or leaf litter) and floodplain pools with Gambusia, but they're typically more abundant in fish-free pools with amphibians.

[Debecran]

I happened upon some of these many years ago at my grandmother's house. First, there was one clamped onto the toe of a baby terrapin I caught in the creek. Then, I found some attached to grass leaves under water, that had been left in a cow pasture by that same creek overflowing, not many days earlier. In graduate school, my Freshwater Ecology professor, Dr. Dan Hornbach was using them in research. Alas, that was many years ago, I am now retired, and try not to crawl through the mud and water...that would only mean I had fallen and I don't bounce but rather break nowadays. Anyway, if anyone knows where these could be purchased or begged from, please let me know. I would really like to have a few in my aquatic plant tank.
Debbie Cranford

Edited by Debecran, 04 December 2017 - 01:46 PM.

[gerald]

" ... and try not to crawl through the mud and water ..."   That's the saddest thing i've ever heard; I hope to be crawling through muddy water until the day I die.   I will check around my various plant tubs and see if I can scrounge up some pea clams for you.

[Matt DeLaVega]

I also have a couple local sites that I can net some. So if Gerald can't find any in his tubs, let me know. I do not think they would do well in a new aquarium. Yours may be well established. I think you need a good bit of gunk. Or mulm if you prefer.

[Debecran]

I have one with "gunk", 1 just set up, 1 coming along nicely, and 1 that is established. I use live plants in all. I have Physa snails the last, cleaning up some to promote the growth of infusorsia. Most of my tanks have softer and more acidic water than normal... for killifish. A small pre-formed pond outside for shubunkins and a couple of koi.

I am now 64 yo. I did a LOT of crawling around in mud and water from the time I could sneak away get in it until a few years ago. My mother must have told me a million times that little girls were supposed to have clean fingernails! Little more difficult now and a lack of nearby water...other than marine and drainage ditches for agricultural and runoff. Our altitude is about 40' feet above sea level. When my daughter comes to visit (taught her well!) she and my 2 granddaughters (and she is teaching them well!!), we do go to the beach and mud flats to see what we can find. 

I would happily pay for the clams and the postage if someone could round up a few and not have to ship them overnight with those exorbitant.costs.

[Moontanman]

So, after observing these guys for a while, I have found something interesting...

They have a tendency to hang out in floating clumps of algae. I am not sure if they were already in the algae and the oxygen bubbles caused the algae mat to lift them to the surface or if they crawled their way up the sides of the tank. But given that I found 23 of the little clams in a single clump of floating algae, I suspect that they seek the floating clumps out.


Someone with more knowledge than I about these things(ahem... Gerald) told me that they do not persist long in the presence of mosquito fish. If they seek the highest level of their environment, this may help explain why. Surface feeders would obviously have more impact on them if they are spending their time near the surface of the water. While they cannot eat the adult clams, they may be able to eat the babies.

I need to get some mosquito fish and test this idea...

 

Have you tried keeping this small fish like least killifish? I have a colony of least killies I keep in a 30 gallon , I'd be will to swap few killies for a few of the clams. Do you think they would in a tank with the least killifish? 

 

 

[Debecran]

I keep 3 species off killifish and apx 15 of another species eggs have hatched 3 days so. My smallest are Clown Killifish. Killifish need a lower pH than a lot of fish but my nerite snails seem to be doing OK. (Their shells don't seem to be getting thinner, which was my only concern.) But hey, I would make a tank for just the clams if I needed to and of course if somebody is willing to sell and ship me some. I haven't heard back from anyone to make the arrangements.

[gerald]

Sorry about that.  Here's some from my Nuphar tub, where they've been reproducing for several years.   Some of them get up to about 10 mm but these look like all young-of-year, about 4 to 7 mm.  Maybe they're "annuals" ?  Send me your address if you want these.   Sphaeriid PeaClams NupharTub.jpg   131.67KB   3 downloads

[Matt DeLaVega]

I am seeing lifespan as 1-3 years. I suppose that may vary by species, good luck determining that.

 

https://nas.er.usgs....x?SpeciesID=129

 

https://nas.er.usgs....x?SpeciesID=131

 

https://link.springe...A:1004066609445

[gerald]

15 fingernail/peaclam species reported in NC:  http://nc-biodiversi..._2017-11-03.pdf

Based on range mine could be any of these except probably not the Little Tennessee species (Rusty peaclam).  I've never tried keying out Sphaeriids. Maybe Debecran will give it a try.

[Moontanman]

As soon as I get out collecting again i plan to give them a whirl... 

[Matt DeLaVega]

I have enjoyed reading more about them. Glad this topic was brought up. These guys are one of those things that I run into. that I fully intend to learn more about, then drop the ball. Well while reading up on them, I found this. http://www.aces.edu/pubs/docs/A/ANR-1340/ANR-1340.pdf I found it interesting, but not totally surprising that native fingernail clams, and the few native unios that can live in man made ponds are generally not a problem. Zebra and quagga mussels and corbicula seem to still be a major problem even in a farm pond! One of the most artificial habitats I can think of besides Rubbermaid tubs and aquaria. Why? What in this mostly artificial environment still provides balance with native mollusks but still allows these introduced species to become invasive?

[Moontanman]

I have enjoyed reading more about them. Glad this topic was brought up. These guys are one of those things that I run into. that I fully intend to learn more about, then drop the ball. Well while reading up on them, I found this. http://www.aces.edu/pubs/docs/A/ANR-1340/ANR-1340.pdf I found it interesting, but not totally surprising that native fingernail clams, and the few native unios that can live in man made ponds are generally not a problem. Zebra and quagga mussels and corbicula seem to still be a major problem even in a farm pond! One of the most artificial habitats I can think of besides Rubbermaid tubs and aquaria. Why? What in this mostly artificial environment still provides balance with native mollusks but still allows these introduced species to become invasive?

 

 

That is why we need to introduce sheepshead fish (Archosargus probatocephalus) to those bodies of water, rumor has it they live well in freshwater but do not reproduce...