Sunday, August 31, 2008

Satellite Image Of Chlorophyll-a In Lake Harris

Above is a satellite-based spectrophotometric image of Lake Harris in Randolph County, Alabama. From the upper left flows the Tallapoosa River, and from the right is the Little Tallapoosa River, all damned to form the lake. What this shows is a very high nutrient level in both tributary rivers and the lake itself, as indicated by high levels of suspended chlorophyll pigments in the water from the presence of one-celled algae.This is especially striking since it was made in April, before typical algal blooms begin. Thus it's a good illustration of how polluted from excess nutrients this river system has become. And it's a graphic illustration of how strongly altered these streams are now, and a measure of what bad habitat they've become for a fish species like the stippled studfish that required clear, low-nutrient water. Our field research indicates that the stippled studfish is found only in tributaries to the Tallapoosa downstream from this lake. The lake may serve a useful purpose as a nutrient sink, trapping much of the crapola in the rivers as they flow out of Georgia.

I'd like to thank Prof. Han at the University of Alabama in Tuscaloosa for preparing this image.

Friday, August 29, 2008

ASB Meeting In Huntsville, AL, In 2011

The Association of Southeastern Biologists (ASB) will meet in Huntsville in March or April of 2011. I will be working as local host on behalf of our Department of Biological Sciences at the University of Alabama in Huntsville. This meeting draws upwards of 1200 participants, so it's a good-sized meeting. It will take place at the von Braun Center (VBC) in town (yeah, shooting Nazi rockets and all of that stuff...) which will be a good venue.

I was part of an ASB group that toured the VBC this morning. We stared at all of the rooms in the place, figured out what events can take place where, and kicked around ideas for food and opening receptions (with barbecue? who knows?). I'll be the one receiving abstracts for talks and posters, which will hopefully be automated by then. I hope to set up a special session or two involving native fishes, maybe with NANFA participation. So I'll help to set up and run parties, and also set up and run academic type presentations, the meeting will go by like a blur I suspect.

My next posting should involve some figures relating to stippled studfish habitat, especially eutrophication of the Tallapoosa. I thought I had it with me this evening but I didn't. Travis and Kris were working this afternoon on purifying DNA from gel cutouts using the Geneclean kits, I'm still not sure what happened. If anyone knows, please tell me.

Tuesday, August 26, 2008

Looking For Other Information About Stippled Studfish Habitat

We've largely finished our sampling of the Tallapoosa basin for stippled studfish, and I think we've demonstrated that the species' range is relatively limited. I've found two sources of information about the physical condition of this basin. The first is Professor Han from the University of Alabama in Tuscaloosa, who's a geographer working with remoting sensing data. He has a set of images that show the Tallapoosa River and Little Tallapoosa River to be largely eutrophic (nutrient enriched), with the exceptions of the impoundments Lake Wedowee (a.k.a. Harris Reservoir) and Lake Martin which are strangely low nutrient. Some of the Tallapoosa tributaries where we collected stippled studfish such as Hillabee Creek show up as low nutrient too, which would be my guess from having seen the clear water of the creek. And this low nutrient environment is crucial to stippled studfish, since they don't do well with creeks with algae growing both on the bottom and in the water column.

The other source of information is something I'd heard of before but hadn't thought to check for this project until I stumbled upon it last week. The U.S. Geological Survey has done a series of Aquatic GAP projects around the country, which basically assess aquatic habitat as being suitable for various species. There is a GAP group based at Auburn who have a very extensive list of likely habitat maps for fish species in the Alabama-Coosa-Tallapoosa rivers system. Stippled studfish are of course really only found in the Tallapoosa, and the GAP map shows likelihoods of finding the species in various parts of the Tallapoosa that generally correspond to whether or not we found the species. For instance, for most of the Cleburne/Randolph counties area the map shows a low likelihood of finding stippled studfish, and we certainly didn't find the species in that area. But the map shows a reasonable likelihood of finding the species in parts of Georgia in which stippleds haven't been seen in ten years or more, so it's an imperfect system. I hope to get some of their published work soon so that I have a better idea exactly how they made these decisions.

We're making progress on the telescope shiner article. Brittany has devised a third figure that represents monthly ovarian maturation status from February through August. That was the last missing results piece, so hopefully the article will come together now. We have three figures and a table for major results, so we can move on to writing that up and weave together a Discussion of what it all means. I still lean towards submitting it to the journal American Midland Naturalist out of Notre Dame.

Wednesday, August 20, 2008

A .pdf Of My Notropis Shiner Article

For a view or download of my article in S.E. Naturalist last December, visit this link:
Observations on the reproductive biology of two Notropis shiners.

Monday, August 18, 2008

Photos Of Cohobadiah Creek On August 8

Here are two photos of the one good stream we found on our last trip to the Little Tallapoosa River system on August 8. On the map it's labelled as Cohobadiah Creek (pronounced "Coh-WHO-ba-die-ah" by locals) although one truckload of passersby claimed that it's really Cool Springs Creek, and indeed there is a Cool Springs Church about a mile down the road. It's just inside of Randolph County on a dirt County Road. The county line between Randolph and Cleburne counties is marked by a poorly paved road in Cleburne County becoming a dirt road in Randolph. The surrounding land is apparently owned by a mining company who used to mine coal in the area, and there are poorly gated mine shafts in the area. Even weirder, there may be some gold in the area, which of course attracts people into the abandoned mine shafts with predictable results.

So, the water in this creek was clear although there was a layer of sediment on the bottom which is why it looks reddish-brown in the first photo. We caught a fair number of fish, especially tallapoosa and bandfin (maybe striped?) shiners and more than the usual number of stonerollers and creek chubs. But, no stippled studfish were found. Even though this creek is in better shape than others locally, it still has no good habitat for stippleds: long stretches of sand, especially in areas of sunlight. Instead the creek bottom was mostly bedrock and cobble, with some gravel. So it's another case of no good habitat meaning no stippleds are found locally, one of the big themes of the summer.The photo below shows a pool constructed by some local people just below the bridge. It's surprisingly well built. The intention of this dam is to create a swimming hole, especially for a legless man who can be driven to the edge of the pool and slide into the swimming hole. I admit that's a first for me. The guy who told me all of this was driving an ancient pickup, with a heavy theme of flaming skull decorations in the cab and his tattoos. I also asked him if there was any timber activity locally, and he said no, explaining about the coal mines and shafts.
This sad result along the Cleburne/Randolph county line furthers my interpretation that stippled studfish are now found no further north than Cornhouse Creek in Randolph County. Cohobadiah Creek flows off of Turkey Heaven Mountain to the north. Such creeks are usually cleaner and have a higher gradient than what we found in the area, so if Turkey Heaven's creeks were ever habitat for stippleds that's long gone as these creeks have been degraded. What surprises me is that a relatively sparse human population has had this profound an effect on the area.

Tuesday, August 12, 2008

A Weekend At Dauphin Island And The Mississippi Coast

I stayed at the Dauphin Island Sea Lab at the mouth of Mobile Bay this past weekend, largely doing my job as liaison between UAH and DISL. I met the new director, Dr. Scott Quackenbush, and talked about DISL's summer school offerings and how they might better serve more students. A big question is scheduling classes so that they don't interfere with the member schools, both at the beginning and the end of the summer. I don't have any snappy ideas on the subject, but then we haven't had any conflicts with UAH classes so it's not an immediate problem for me. All of our students did well this summer as usual; they go to DISL to study and have fun, not to drink beer 24 hours a day (round up the usual suspects).

Ruth and I also spent much of a day driving out along the Mississippi coast looking for a suitable spot to collect some longnose killifish, Fundulus similis, for my long-term study on the population genetics structure of F. similis and its very close relative, F. majalis, from the Atlantic coast. We found a good spot in the town of Pass Christian at the boat marina (the one with the restaurant called Shaggy's). As the tide was going out along the sandy beach we were able to seine 14 subadults from water's edge, which is the typical habitat. They are the westernmost population I've been able to collect. Not very far to the west of Pass Christian the coast becomes tidal swamp and is much more difficult to collect along if you don't have a boat, which I don't. So Louisiana might be problematic for this project. The goal is to collect samples roughly every 200 miles along the coast, from Massachusetts at least to Texas, and I've been able to make several collections along this length. Right now I need fish from at least one site in Texas, as well as the Florida Atlantic coast, Georgia, North Carolina, the Delmarva, New Jersey and New York; I have samples from Nantucket and mainland Massachusetts. This collection might be my next summer's project.

On a purely political note, we also spent an afternoon in New Orleans around the French Market and the Quarter. The place is still recovering from Katrina, but what struck us was the ubiquity of Obama for President material. The tourist traps on Decatur Street all sell at least one type of Obama t-shirt, and a lot of the vendors in the French Market, too. And nary a McCain object in sight.

Wednesday, August 06, 2008

The Little Tallapoosa System Is A Mess

We made it down to the Little Tallapoosa River drainage yesterday, along the Cleburne and Randolph County border. The river enters Alabama from Georgia here, and it's a mess. Below is a photo of the Little Tallapoosa at Cleburne County Road 49 near Ranburne, AL. If, as is likely, this river supported stippled studfish populations, it doesn't now. It's loaded with sediment and the substrate is soft unconsolidated sediment. Several creeks we looked at were smaller versions of this, the result of agricultural land uses and attendant nutrient enrichment running off into streams. All of the structures I saw in Google Earth images that I thought were poultry houses, really were, and there are lots of them in this area and upstream in Georgia. So there are a lot of relatively small contributors to these degraded streams, which is a sad story; you can't blame any one polluter because it's really almost everyone. Below is Knockes Creek along County Road 10. I had high hopes for this creek because it runs off of Turkey Heaven Mountain, a forested area with no poultry farming. But it turned out to be a mess with tires in the creek and broken glass all over, not even counting almost no current, heavy sedimentation and aquatic vegetation more typical of a pond than a creek. We didn't bother to enter the water.
The one kinda OK creek was Cohobadiah Creek just across the Randolph County line. But like some creeks we saw last month, it had the wrong morphology for stippled studfish; rocky but no sand. We found lots of tallapoosa shiners and burrhead shiners there, but no sign of stippleds. At that point it was very hot and we had run out of possibly OK creeks, so we called it a relatively early day.
So there don't seem to be any stippled studfish populations in Cleburne or northern Randolph counties; Cornhouse Creek is the northernmost population now, in central Randolph County. This further reinforces my view that this species is now limited to 6 populations south of Lake Wedowee in Randolph County, and to the south in Tallapoosa, Coosa and Elmore counties. The Tallapoosa River south of Lake Wedowee may be able to support stippled studfish, we haven't been able to test that. If so, the 6 extant populations may not be totally isolated. We'll see, as always.

Sunday, August 03, 2008

New, Improved DNA Purification Kit (We Hope)

On the advice of Leland in another lab, we're switching to GeneClean kits for purifying DNA from gels of PCR products. Leland's experience is that the Qiagen kit we've been using tends to trap too much DNA during purification, leading to low DNA concentrations in your product (kinda like we've found). So, for another $146 and change, I'm ordering a kit good for 200 preps. Hopefully we'll have it by the end of the week and it'll make a difference as we PCR our current purified PCR product. We don't even have 40 samples in our screening of stippled studfish DNA, so that kit should do us. The piss of it is that I still have a fair number of the Qiagen spin columns used in their process. And I'm still within budget for the project; since I'm not getting Defense or NASA money I pretty much have to stay within budget, of course...

Joe Scanlan is up for the trip to Cleburne and Randolph counties on Tuesday. I've been looking at Google Earth images of the area, and I've found lots of commercial-size poultry houses scattered about the countryside. This isn't a good sign; large-scale poultry farming almost always releases lots of nutrients to local streams causing algal blooms and fish kills, just the kind of environment for which stippled studfish have a very low tolerance. I've found maybe two sites we'll visit that seem removed from poultry housing, and two sites that are unfortunately close to such farming. One of these sites is at the Little Tallapoosa River, which seems to be small enough to be sampled by seining. As always, we'll see. The weather forecast is for extremely hot and humid that day so wading in even a eutrophic stream will be refreshing.