38 replies to this topic

[Auban]

So, today I went out to a few locations nearby to look for new plants and/or new vernal pools to sample.

It's a hobby of mine, one that takes my mind off of my day job for a little while.

Anyway, I found some pea clams in some vernal pool dirt and detritus that I collected. I have already put the dirt, leaves, etc, in a tank to see what will hatch out. That's when I noticed the clams. I have never encountered them before, and I was wondering if anyone had done anything with them. So far, they have been in the water for about an hour.

When I looked at the tank a minute ago, I was surprised to find what looks like tiny mosquito larvae and a few of those tiny clams. They have not opened up and started moving yet, but since they are at the bottom of the tank, I am assuming they are alive. Otherwise, they would be dried out and would be floating.

Does anyone know of a good source of I formation about these things? I have Googled it for a little while but haven't found a whole lot.

Edited by Auban, 22 July 2017 - 05:13 PM.

[gerald]

Sphaeriidae clams just don't get the attention that those charismatic mega-bivalves the Unionidae do (river mussels).  No amazing mantle-lures, no fish-parasite stage, and not used much for water quality assessment since they're hard to ID to species and most of them are pretty tolerant of low oxygen.  I have some in my outdoor plant tubs that came in on Nuphar roots many years ago.  They are live-bearers.

[Auban]

They sound awesome. Do you know what their conservational status is? I would love to try culturing them, but I don't want to get ahead of myself. If I need to get a specific license to keep them, I don't mind getting one. If I have to destroy the ones I have in order to do so, I don't really have a problem with that. I know where to get more, obviously.

I just don't know much at all about them. Since they are vernal pool critters, I am already interested in them. I am continuously surprised and delighted by what I find in vernal pools...

Edited by Auban, 22 July 2017 - 07:08 PM.

[Auban]

They are alive! I am excited as hell!

I just witness one of them crawling up the side of the tank, just like a snail.

Awesome!

[Moontanman]

They are alive! I am excited as hell!

I just witness one of them crawling up the side of the tank, just like a snail.

Awesome!

  You mention you found these in a vernal pool? Could they be clam shrimp? Clam shrimp are often found in vernal pools. 

 

https://en.wikipedia...iki/Clam_shrimp

[gerald]

Clam shrimp swim; fingernail clams don't.

[Moontanman]

Clam shrimp swim; fingernail clams don't.

 

 

Ok, but he did mention they were climbing up the sides of the tank. We have clam shrimps here in NC, they do look surprisingly like actual clams. On the other hand I have also seen a type of tiny clam that attaches itself to plants as well. The vernal pool thing threw me off a bit... 

[Auban]

I have cultured clam shrimp before. They are not what I have in the tank.

These are tiny clams.

[Auban]

So, has anyone cultured these before? I looked in the tank today and the tank was already showing signs of going very eutrophic. Slight discoloration, bubbles foaming a bit at the surface, a slight smell that I cannot quite describe that always precedes the tank fouling...

So, I moved the whole tank into a larger tank. I now have them in a 75 gallon tank. Ill be keeping them in there and seeing what happens. I put lights on the tank to make it grow lots of algae. That will help keep the water quality good.

I'll also add an airstone to slowly circulate the water.

[Auban]

After doing a lot of googling, I have come to the realization that there really just isn't much known about pea clams.

[gerald]

Can you find a copy of Thorp & Covich's Freshwater Invertebrates?  That should have general biology info on them.  As I recall (from Sam Mozely's invert biology in the 80's) they feed mostly on the fungi/bacteria/protozoa slime on decaying leaf litter, and not so much filter-feeding from the water like larger clams.

http://mkohl1.net/Sphaeriidae.html

[Auban]

I'll see if I can find a copy. If not, I may try contacting some of the people who have published content on them. In the past, I have been successful in getting access to academic papers by simply being willing to tell them where I found stuff and what I am seeing as I culture them.

I might be able to access such papers through the defense language institute. Despite the fact that I am in the army and have never done the regular college thing, I actually have about 90 college credits and am only a few credits away from finishing a couple degrees.

So, I may be able to use one of my accredited institutions to gain access to relevant published studies. I'm not sure how that works. I'll contact the army education center and see what I can do.

[lilyea]

Voshell (2002) has an image plate and two page description of Fingernail or Pea Clams (Family Sphaeriidae) and describes their feeding as "collector-filterers" (p. 228-229).  The section also describes their burrowing that allows them to be the primary bivalve in temporary water habitats and other intermittent ponds although a dry period is not required.

 

 

Voshell, J. R. (2002). A guide to common freshwater invertebrates of North America.  Blacksburg, VA: McDonald and Woodward.

[Moontanman]

After doing a lot of googling, I have come to the realization that there really just isn't much known about pea clams.

Do the clams have thin shells? The ones I get have shells so thin handling them can cause them to collapse. Fish seem to eat then almost immediately. You "flung a craving" on me, I'll have to go and collect a few. That they eat more like snails than clams is intriguing. Being livebearers pretty much seals the deal. 

[Auban]

Do the clams have thin shells? The ones I get have shells so thin handling them can cause them to collapse. Fish seem to eat then almost immediately. You "flung a craving" on me, I'll have to go and collect a few. That they eat more like snails than clams is intriguing. Being livebearers pretty much seals the deal.

Their shells are certainly thin and can be crushed, but no thinner than you would expect a small clams shell to be. They are certainly not as thin as clam shrimps.

I haven't been able to observe them enough to see them eating, but it would make sense if they eat like a snail. They move a lot like one.

[Moontanman]

Their shells are certainly thin and can be crushed, but no thinner than you would expect a small clams shell to be. They are certainly not as thin as clam shrimps.

I haven't been able to observe them enough to see them eating, but it would make sense if they eat like a snail. They move a lot like one.

 

 

I've noticed that very small asian clams are quite tough, we have lots of them here. The small clams that attach to plants are very fragile, fish eat them easily but they are clams. I find them in streams that flow through to swamp. We have clam shrimp here as well but they only occur in vernal pools.. 

[Auban]

If I could find some clam shrimp in vernal pools, that would be amazing. I'm not sure what it is about vernal pools, but I absolutely love them. If clam shrimp are here, I would absolutely love to find them someday.

Everything I have found in a vernal pool I have found a use for. And I have sampled hundreds of vernal pools...

One type of vernal pool that many people don't think about is roadside ditches and drainage retention ponds. If you exclude those, I have sampled a few hundred vernal pools all across the country. If you include them, I have sampled a few thousand. Before I joined the army, I used to go searching for drainage ditches full of water and see what I could find, all the time. For years. I would often go out on a weekend and spend the whole weekend sampling drainage ditches. I always found it remarkable how one drainage ditch would have an entirely different set of organisms from one just a few hundred meters up the road. I would take samples home and use my trustee old American Optics 150 microscope and see what was living in it. Never did see a waterbear...

I used to want to write a book about all the stuff I was learning about and finding in those ditches. I was going to title it "Ditch Biology", targeted to kids. Kind of a play on words, since I learned more about ecology and biology from sampling those roadside ditches(and subsequently looking everything up in the library or online) than I ever learned in school. In my mind, if people are really interested in ecology or biology, they could start learning about it in the same way I did. By just getting out there and seeing what they find. At best, they would know if it's a field they really want to go into before they have to make that choice. At worst, they would learn a little about the world around them.

Anyway, moontanman, shoot me a PM and I will tell you where I collected the clams. If you know of any institution that would like such information, I'm all ears. Im happy to report what i find to anyone who may be interested. If i stay in the army until I retire, my hobby is going to be sampling every source of water within reach to find out what lives where. It's actually already my hobby... with what limited time I have at home, I have gotten pretty efficient at selecting sites to sample, depending on what I am looking for. Takes me about 10 minutes to select a site. Takes me hours to really explore it though...

[mattknepley]

So, lemme git this straight; they're clams, but they crawl and eat like snails, have live young 'uns, and live in waters that dry up? And they're clams? How dang charismatic has a mollusk gotta be to compete with those mussels?

You musta been with me in spirit Sunday, Auban. I was in Jasper County, SC and had just enough time to squeeze in a stop to check out Sgt. Jasper Park. A quick drive to the park showed plenty of good an' interesting looking habitat with signs that actually encouraged fishing. Turned out you needed a $5 day pass to fish, which I would gladly pay, only it was late afternoon and I still had ~3 hours to drive and a slobbering Great Pyrenees with me. So I settled on dipnetting a roadside ditch next to one of their disc golf "holes". Several Least Killifish, a surprising number (to me) of pygmy sunfishes (Banded for sure and I think one Everglades), one dragonfly larvae, swimming "bugs" that looked like daphnia on 'rhoids, no fewer than 47,000 aquatic spiders, and gambusia so small that several were outsized by the female Least Killis.

And now you guys have me wondering what all I missed! FWIW, there is a definite need for the types of projects like your "Ditch Biology" one. Before this blessing and curse of internet and video, many more kids grew up focusing on the world around them rather than the screen in front of them...

So really, they eat and move like snails, bear live young, and live in waters that dry up? And they're clams? That's new to me...

[gerald]

Fingernail clams are pretty easy to find in swampy streams and floodplain pools throughout eastern NC; they can coexist with Gambusia,  Clam shrimp and fairy shrimp are much less common and rarely persist long in waters where Gambusia have access, so they're mainly in vernal pools that don't often get flooded by creeks.  There's some suitable pools in the Sandhills Gamelands area.  Several rare frogs and salamanders also specialize in those habitats.

[Auban]

So, lemme git this straight; they're clams, but they crawl and eat like snails, have live young 'uns, and live in waters that dry up? And they're clams? How dang charismatic has a mollusk gotta be to compete with those mussels?You musta been with me in spirit Sunday, Auban. I was in Jasper County, SC and had just enough time to squeeze in a stop to check out Sgt. Jasper Park. A quick drive to the park showed plenty of good an' interesting looking habitat with signs that actually encouraged fishing. Turned out you needed a $5 day pass to fish, which I would gladly pay, only it was late afternoon and I still had ~3 hours to drive and a slobbering Great Pyrenees with me. So I settled on dipnetting a roadside ditch next to one of their disc golf "holes". Several Least Killifish, a surprising number (to me) of pygmy sunfishes (Banded for sure and I think one Everglades), one dragonfly larvae, swimming "bugs" that looked like daphnia on 'rhoids, no fewer than 47,000 aquatic spiders, and gambusia so small that several were outsized by the female Least Killis.And now you guys have me wondering what all I missed! FWIW, there is a definite need for the types of projects like your "Ditch Biology" one. Before this blessing and curse of internet and video, many more kids grew up focusing on the world around them rather than the screen in front of them...So really, they eat and move like snails, bear live young, and live in waters that dry up? And they're clams? That's new to me...

That's the kind of experiences I have had with drainage ditches. There is NO TELLING what you will find. 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. I have found salamanders, frogs, all kinds of daphnids, ostracods, jellyfish, catfish, baby turtles, etc. I even caught a little garter snake once. What was even cooler was finding populations of little fish that looked different from normal. Like a Gambusia population where all the males are black and white. I used to catch black and white gambusia males from time to time, but I had never seen a population where ALL the males were black and white. I had been trying to breed them to produce the black and white ones, but I had never gotten them to breed true. The genetics seemed tricky...

Makes me wonder what was going on there? What selection pressure favors the black and white ones?