This site is ripe for a serious outing.

Earlier today I stopped by one of my usual locations on Swamp Creek, about 5 miles from its Conasauga River confluence. The first thing I noticed was a lot of turned gravel in mound like structures. Then noticed what was apparently either White sucker (Catostomus commersonii) or Black redhorse (Moxostoma duquesnei). From the bank I could see the slightly arched back, sucker snout, ans some distinct redishness around the lower fins. They were loosely swarming a shallow pool between riffles.

After dark I went back with a flashlight and a camera. The numbers and diversity of species was greater than I have ever seen at this location. Seen a lot of different that was impossible to identify from a distance but one appeared to be a Striped shiner (Luxilus chrysocephalus). The Rainbow shiner (Notropis chrosomus) in full color was unmistakable. There were some other suckers likely either Northern hogsucker (Hypentelium nigricans) or Alabama hogsucker (Hypentelium etowanum). Something else I noticed was the pond snails that are normally a range of sizes and ages were all young and tiny.

Good pictures are very hard to get in the dark with a flashlight but I got one good picture of a Southern studfish (Fundulus stellifer).



Here is a zoom of it:


Not bad with a flashlight at night.

I just noticed what appears to be eggs in the gravel just below the fish in that pic.

Jump In.
This time of year is great for some up close and personal snorkeling.
Rainbow Shiners... awesome. Lay in next to those gravel mounds and watch the show.

Today I did get in. Waded about a half mile of that section of creek. Did not realize till I got back that the memory card for my camera was still in the computer card reader.

Hey Casper, you want to come down and seine a little on swamp creek? I can provide a full species list of what can be expected. I need a good seine and photo tank. My nets work best at night and my throw seine is limited in shallow regions.

The recent heavy rains has created a pool completely cut off from the rest of the creek. I believe I seen rainbow shiner in it but it is harder to tell from a distance during the day. The color does not show as well and it is harder to get as close, hide under a root mass when approached. They looked more like zebra danios at a distance in the daylight due to reflections giving the apparent multiple stripes. So it could have been Burrhead shiner. They were also just below were the rainbow were last night. All I had was a small hand net but I will be checking back on that pool often. I will be wanting to keep some of them soon.

The water is crystal clear with brilliant green algae growing on the bottom rocks. The moss was limited to above the water line. This is a riffle area interspersed with slower pools and a few slower moving shallows. The areas deep enough to snorkel are fairly limited but likely worthwhile. The only suckers I seen today were the smaller Alabama hogsucker. I seen a lot more shallowed out depressions in the gravel but did not see the fish associated with them.

Burrheads are definitely sediment divers, more so than most shiners.

I did not know that about burrheads. The thing that makes me think rainbows is that I am accustomed to tricks of lighting make it appear like they have 3 strips in a spotlight or 4 in daylight. The reality up close is different from perceptions at a distance through water. Burrheads tend have the appearance of 2 stripes or transition in spotlight. What remains of the water feed for the pool they were in is also the shallow area the rainbows were in last night. Identification based on obscure tricks of lighting is usually problematic at best but something I am accustomed to. I can recognize certain snakes by the sounds they make crawling through leaves also, especially hognosed snakes. There were other cyprinids in the same pool to. The pool was not the ideal hangout for rainbows but anything in there is trapped.

I took pictures but had forgotten to bring the memory card. Why the Canon Digital Rebel EOS takes pictures and displays the 2 second preview without a memory card present I do not know. I use the eyepiece rather than the LCD so I did not see the no memory notice before each pic.

I went back for a long trip up Swamp Creek again, and remembered to bring the memory card for my camera this time. I started at the original location and winding my way all the way upstream to the beginning in the mountains. So I will start here at the lower regions. The album for this trip can be found here, which I will add to as I post:
http://gallery.nanfa.../mywan/May-2nd/

Lower riffle region:
Gone was the brilliant green filamentous algae on the bottom and the snails are maturing, but it appears to be a different species of physidae than what usually dominates. The usual most abundant appears to be Physa acuta(?) mixed with a with one with a much longer spiral. Apparently the heavy spring rains stripped the snail population clean, allowed an algae bloom, followed by a the snail eggs hatching a new crop of snails. I suspect, based on both river and tank observations, these snails are having a negative effect on green algae that goes beyond simply eating it. These snails usually form a thick coating over nearly the whole bottom of the creek. I also want to know more about which fish are predators of these snails.

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These things, eastern dobsonfly (Corydalus cornutus), were thick (mass emergence) and many stuck wiggling in spider webs over the water. From a distance you could see fish trying to jump high enough to get at the ones struggling in webs. When you catch one it no longer looks like it has white spots but it was impossible to keep them still enough to take a photo. Nice source of fish food but also highly predatory in the larval stage. Most of the white you see in the pic is actually in the web.

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Next up is a very sick unidentified fish (poor thing). Perhaps I can get some help on this but no fish listed for the Conasauga region seemed to fit completely, but perhaps a redhorse of some kind. This one was far easier to sneak up on for photos than any others but it would still meander away if you splashed or moved too fast. Otherwise it would just slowly meander in a small circle.

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I wonder if the cyanobacteria in the following photo has something to do with the sick fish. This is in a side pool just upstream from the sick fish. Last year is was clean and harbored many tadepoles, but since finding a bag full of dirty diapers in it early last fall it has been like this. I would like to learn more about what this means to the water quality?

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Here is another sad case, but apparently just an accident while going over a little fall. It apparently got wedged in the thick stems as it went over.

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The following fish photos are not nearly as clear as the sick fish. Fish are hard to sneak up on. I also need a better telephoto and a polarized lens filter. I guess I should go ahead and order the polarizer. Here is a redeye bass (Micropterus coosae). You are likely to see more by clicking the image for a larger photo.

EDIT: Wrong pic, wrong location. Likely wrong about ID. This pic belongs with the group upstream in an upcoming post

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Here is another good redeye bass pic if you zoom in the larger picture. I tried to get the small school it was with in the picture it did not come out that well so I got the school separately.

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Here is the school near the second redeye bass. You can see the redeye bass to the right near the edge of the shadow. It takes a little patients just to shift my position while only making them a little suspicious and then wait for them to calm down and go back to being fish.

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Here is a large sunfish. I have trouble with sunfish IDs but presume this is a redbreast sunfish (Lepomis auritus) based on the fact that the two edges of the black ear flap were parallel and the ear flap angled slightly up and back. It was a bit too cautious for me to get a better angle. Ever time I tried it ended up somewhere other than in the picture. It was fairly large for a redbreast, about 8 inches.

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The rest of the fish photos at this location is pretty non-specific or not relevant. I will follow up with some pictures to show perspective here, and then move on to the upstream areas.

Edited by mywan, 02 May 2011 - 06:51 PM.

Here are some pics giving some perspective of the area I was in. This is looking downstream from about where the redeye was and the sick fish behind me. Just on the backside of that grass island nearest me is where I took the pick of the southern studfish (Fundulus stellifer) from the first post. That location now has lots of very tiny fry, but the pics did not come out so well on them. The shallow grassy area on the far left side is where I seen the rainbow shiner and below that is the trap pool. The deeper overflow on the right side is where the fish got stuck in the vegetation as it went over and died in the pic above.

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This is looking upstream from near the same location.

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This is the trap pool, which is a bit larger than what it looks like here. The shallow rainbow shiner location is behind me in this pic.

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I would also like to identify this plant. It is the most abundant biomass of plant in the creek both summer and winter, though the root system is mostly what hangs on through the winter. It forms a mass of runners and root system over areas of the stream bed. It is also the plant that trapped the fish that dies going over the little water fall. You can see parts of it in the first, second, and fifth pic above.

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This area is characterized by a very high pond snail population with a low green algae, riverweed, and moss populations. There is also a significant population of Southern two-lined Salamander (Eurycea cirrigera) here. Though the algae will bloom rapidly without the snails as evidenced following high water when the snails were washed out. Several areas had the stoned washed off the bottom exposing very soft gooey white clay (kaolinite), which can look like muddy water from a distance. Though the water over it is actually quiet clear. The species conspicuously missing from this part of the creak is hogsuckers (Alabama or northern), and any sculpins. This changes and other characteristics change significantly several miles farther upstream and into the mountains, which I will get to in another post.

Nice shots! I love that area.
I believe your sick fish is a large male Luxilus chrysocephalus. I have seen males of this species and Campostoma sp. in similar condition during spawning season; I would guess their spawning-related stress levels have more to do with it than water quality issues. The plant looks like water willow, Justicia americana.

Those snails appear to be a pleurocerid. I want to say Elimia, but I'm not sure. In the smaller streams, crayfish are probably the major snail predators. In mid-order creeks and larger, turtles (especially stripeneck musk turtles) and drum eat a lot of snails; I've seen large populations of both in the Conasauga. I'm sure suckers, sunfish, bass, and some darters take them opportunistically as well. Etheostoma blennioides is a snail specialist in the Tennessee drainage, but I believe it is absent from the Conasauga. Lepomis auritus is also a snail specialist, but is usually in sluggish waters.

Mountain base: Between lower riffles and the mountains:

I made a boo boo in the post above and the first pic label redeye is actually from this region. The other redeye did not come out so well and I think the redeye ID is likely wrong. I have a couple of other pics of that one but I will let it be .

Here is a pic of a Alabama hogsucker (Hypentelium etowanum). There is also a sculpin of some kind in that pic, but if you can see it you have better eyes than I do.



This stretch of river is characterized by the addition of sculpins and suckers seemingly missing further downstream. The snails are also missing or greatly reduced, but the green algae, riverweed, and mosses in the water are still at a minimum.

Nice shots! I love that area.
I believe your sick fish is a large male Luxilus chrysocephalus. I have seen males of this species and Campostoma sp. in similar condition during spawning season; I would guess their spawning-related stress levels have more to do with it than water quality issues. The plant looks like water willow, Justicia americana.

Thanks, I did see them apparently spawning several weeks back right near that sick fish.

Those snails appear to be a pleurocerid. I want to say Elimia, but I'm not sure. In the smaller streams, crayfish are probably the major snail predators. In mid-order creeks and larger, turtles (especially stripeneck musk turtles) and drum eat a lot of snails; I've seen large populations of both in the Conasauga. I'm sure suckers, sunfish, bass, and some darters take them opportunistically as well. Etheostoma blennioides is a snail specialist in the Tennessee drainage, but I believe it is absent from the Conasauga. Lepomis auritus is also a snail specialist, but is usually in sluggish waters.

Those snails are different from what is usually most abundant there, but snail ID is hard. Is there any published or other indication that these snails might suppress the growth of certain kinds of algae beyond simply eating it? Several years of tank and river observation has me questioning that. I appreciate the snail predation information.

Good question. I wouldn't think snails would suppress algae recruitment, as it would be disadvantageous to them. Certainly they limit the biomass and affect the structure of the algal community. I suppose you might see snails preferentially grazing on filamentous green algae, which could encourage the growth of less-obvious diatoms and microalgae. If the snails are in a low-flow environment, accumulation of their feces could conceivably render substrate surfaces un-colonizable to certain algae. I doubt that's a major factor in most ecosystems though. Algae display seasonal and hydrological succession through the year, and snail populations fluctuate with this cycle, weather cycles, predator abundance, etc. So apparent correlations between snail density and algal presence may in part be coincidental.

Upper river, in the mountains:

Just as I passed into the national forest area I noticed a farm right on the river with an unusually high fecal load throughout the property and on the road itself. I did not get any fish picks further up than this, as everything I seen was smaller faster and far more skittish. They did not waste time being nervous and was gone as soon as there was any hint of a reason to be nervous. This part of the creek is legally designated as trout water by the state and fall under somewhat different use rules.

The characteristics of the ecology changed pretty drastically though. It was devoid of snails with a very healthy biomass of riverweed and mosses, and also had a fair amount of very mature filamentous algae. The riverbed was coated in drowned caterpillars. Six or eight per square feet any many places and the floor of the forest and roads, when looked at more closely, was specked heavily with tiny black caterpillar droppings. The easiest live thing to find in the water was crawdads. Many plant species not seen or extremely rare down lower were common here. Here is how it looked in general. I want to know more about those clumps of grass also.

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Here is one of the crawdads placed on some riverweed for the photo op. I have pics of another crawdad species not shown.

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Here is some mature filamentous algae not found further downstream.

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One of the caterpillars coating the riverbed. Everything that can eat these must be awfully fat about now.

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This would be an aquarium filter to die for. That is a solid mass of riverweed and mosses, so thick is provides a bed for those grasses on solid rock and slows the water flow over that steep grade way down.

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I got many more pics of plants, bugs, fungi, and other versions of the posted photos but I should place some limits number and relevance. There was one beatle running everywhere with florescent green and black striped wing parts and a shiny reddish gold margin around the wings and midsection and above each eye. I suspect the were collecting caterpillar dropping but do not know. Right now I want to learn more about what I found.

Good question. I wouldn't think snails would suppress algae recruitment, as it would be disadvantageous to them. Certainly they limit the biomass and affect the structure of the algal community. I suppose you might see snails preferentially grazing on filamentous green algae, which could encourage the growth of less-obvious diatoms and microalgae. If the snails are in a low-flow environment, accumulation of their feces could conceivably render substrate surfaces un-colonizable to certain algae. I doubt that's a major factor in most ecosystems though. Algae display seasonal and hydrological succession through the year, and snail populations fluctuate with this cycle, weather cycles, predator abundance, etc. So apparent correlations between snail density and algal presence may in part be coincidental.

I agree that the idea seems at odds with expectations, yet the algae always seems to disappear faster than what seems predation should account for. This applies for aquariums to when only a few snails are added. What really started making me seriously question this was when my brother added a few to a 55 gallon with an algae problem. The few pond snails promptly died and within a few days the algae also died and did not come back for months. Even then it was much subdued over what it was before.

What is needed is an algae tank with some of the algae growing inside a very finely netted box that allows water exchange but no snail access. That would at least establish the first step. The fecal idea does not seem sufficient in my questionable observations. If the fecal matter was sufficient then the snail population would be sufficient to never bring up the question in the first place.

There are good examples where the removal of a predator of a species results in a reduction of the prey population.
Darold P. Batzer, Christopher R. Pusateri and Richard Vetter, "Impacts of fish predation on marsh invertebrates: Direct and indirect effects"
http://www.biomedsea...0000576657.html
Also there is this:
http://www.mendeley....is-using-tanks/

So it is at least in principle possible that the snails benefit more by inducing a food web cascade than they would by the extra supply of food. The snails certainly do not seem to have any trouble maintaining an extremely dense population on the available food with no visibly apparent algal biomass. Perhaps the presents of a fair amount of algal biomass would directly or indirectly encourage predators that would be more harmful to the snails. I cannot think of any other case of species inducing a cascade as a survival strategy, but it cannot be ruled out with what I know.

You have to be willing to be wrong to find anything really new, but it is possible to be wrong and still find something new.

I gots to know - what is that thing in that dog's mouth?

I gots to know - what is that thing in that dog's mouth?

I reach to pet him and he bit my finger then looked at me to make sure it was ok, so I took a pic.

A disembodied human finger - got it! Cool Avatar!!

The water plant in the lower region, that trapped and killed the fish that went over the small fall, is apparently alligator weed (Alternanthera philoxeroides). It is an invasive from South America and is reported to reduce water flow, is not edible to any native species, and can prevent light penetration and oxygenation of the water in sufficient density. The most effective control is the alligator weed flea beetle (Agasicles hygrophila) which was imported for control. This beetle has no other native food source than the Alligator weed.

From what I have observed the alligator weed appears restricted to a relatively short stretch of river, but I will follow it down several miles to investigate. So far the damage it appears to have done to this area is minimal and the root mats appears to be plowed through during high water when the roots mats extend too far out from the banks. I have a picture of this occurring but the mass of what survives the winter has increases over the last couple of years. This hydrological plowing can also result in infestations further down stream due to vegetative reproduction. If this weed get embedded well enough to form thick mats completely across the river, like where it trapped the dead fish, it could potentially prevent the passage of many fish up and down the river altogether. After investigating further downstream I will contact some local or regional agencies to see what they have to say.

Agree with Newts ID's on everything. The snails could also be Leptoxis, if not Elimia (both are in Pleuroceridae).
Black-wing bug in spiderweb looks like Nigronia, similar but smaller than dobsonfly.
Are you sure about alligatorweed in pic with dead shiner? I woulda guessed Justicia like the lower pic.

"beatle running everywhere with florescent green and black striped wing parts and a shiny reddish gold margin around the wings and midsection and above each eye" -- maybe Fiery Searcher, a groundbeetle

Edited by gerald, 03 May 2011 - 05:09 PM.

Quick test to distinguish Justicia from Alternanthera: crush a stem. Justicia has tough stringy stems. Alternanthera has juicy, hollow stems that make a lot of noise when you mash them. (Or you could just wait a few weeks and look at the blooms). I agree that your beetle could be a fiery searcher, though I'm not aware of any with stripes. They are caterpillar predators.