Thursday, November 26, 2009

The Mummichog DNA Consensus Tree

It doesn't look great graphically here, but this is the guts of our results looking at the mitochondrial DNA cyt-b gene of Fundulus heteroclitus populations along the Atlantic seaboard. (Click on the figure to enlarge it.) The F. similis at the top is our outgroup. Using the Tamura-Nei algorithm within the UPGMA tree-building method, the big news is that there is indeed a significant split between the northern populations (Cape Cod, Nantucket Island and Wiscasset, Maine) and southern populations (Chincoteague and Virginia Beach, Virginia; Charleston, South Carolina; and Sapelo Island, Georgia). There are also interesting differences between the Virginia and more southern populations, reflecting a longer history allowing more genetic changes to appear. Our interpretation is that the northern populations show the low diversity due to being descended from a low founding population about 13,000 years ago that remained largely isolated from further immigration from the south (a leptokurtic resettlement pattern). Kris' thesis is almost done, and with any luck he can defend in January. It's real biology!

Saturday, November 21, 2009

Petrified Wood(?) From Tallapoosa County, AL

I spent the day on one of those grueling all-day trips to the shores of the Tallapoosa River in Tallapoosa County, AL. Ruth and I went down with Phil and his son Drew to visit a site we found on the stippled studfish survey in July, 2008. This small creek was set in a shallow valley surrounded by damp fern-dominated bottoms. The only fish we found then were a lot of young-of-the-year cyprinids of some sort (I suspect a species of Lythrurus shiner). But we also found some unusual rocks that appeared to be petrified wood. The only petrified wood known from Alabama is in Marion County. But we discovered that a site in west Georgia has also produced it. So, after 16 months, we finally went back to this site down a long graded dirt road. And we found lots of this material, whatever it is exactly, along with other rocks that seem to be the local feldspar (I think...) bedrock, probably just underlying the apparent fossilized wood we were finding. That would probably make our putative wood no older than Triassic in age, at most ~240 million years old. So anyway, we collected a bunch of samples and Phil and Drew will send some out for analysis by for-real geologists. Here are some pictures from the day. We found no other fossils in the creek bed where we found the apparent petrified wood.

Here are Ruth, Phil and Drew on the bridge over the creek (if it has a name, I don't know it).

This is one of the better rock samples we brought home with us. It looks like it's derived from a tree, which doesn't mean that it is, of course.

A view of this little creek from the bridge. It gets bigger both upstream and downstream. Ruth and I spent some time near a large pool and riffle upstream from here, and I saw mature shiners (pretty shiners?) schooling in a flowing pool, facing into the current.

Friday, November 20, 2009

And, More Pictures From Estill Fork Last Sunday

Here are some more photos from Sunday's trip to Estill Fork, thanks to Tessa. By November it's actually autumnal in north 'bama. The temperature was mild but the leaves have just about fallen...

The first shot is the low bridge across Estill Fork, which I like as a marker of water height and flow.

Brittany and I are walking downstream to do the downstream shuffle transect. The aquatic emergent plants have just about gone by, and been scoured out by high flows.

The driftnet at work, in a lower flow than last month. The steel rods definitely work well at anchoring the net in place.

Wednesday, November 18, 2009

Fish In A Jar From Last Sunday At Estill Fork

These are the recently euthanized fish we collected at Estill Fork. You can see a scarlet shiner off to the right, with an almost coppery color, and most of the rest that are visible are telescope shiners. I sorted through the putative telescopes the other day and removed two tennessee shiners which are very similar at first glance, the major difference being they have smaller eyes. I have other pictures to post later.

Sunday, November 15, 2009

Finally, We Have A November Collection Of Telescope Shiners

It wouldn't seem to be that big a deal, but today's trip to Estill Fork gave us our first collection of telescope shiners for November. We need that to complete our survey of gill fluke infestation rates in telescopes in the Estill Fork/Hurricane Creek system. Today's collection was about 35 telescopes, and thanks to Brittany and Tessa for their part. It was Tessa's first work pulling a seine which I sometimes forget is not an entirely natural skill to possess, especially when dealing with fast-flowing water. But the weather was mild today and the water pleasant (12 deg. C).

And of course we ran the drift net, took a water sample for analysis, and shuffled for macroinvertebrates along our two transects. The immediately obvious difference in today's collection was that some kind of serious insect hatch was happening, and we probably netted several hundred of whatever they are.

The first photo is Brittany and me doing the shuffle transect. I'm wearing my brand new waders, which really truly need suspenders to hold them up.

Here's a close-up of my feet in shallow water, along with the drift net, the two steel rods for staking it in place and the sample bucket holding the drift capture -

Thursday, November 12, 2009

Alabama Imperiled Fishes Meeting Yesterday

Andrew and I drove out yesterday afternoon for the first (annual?) Alabama Imperiled Fishes Meeting at Lake Guntersville State Park. About 30 people participated in this open roundtable, talking about various research and monitoring projects with various species around the state. The one looming crisis involves the spring pygmy sunfish (SPS), whose fragile habitat to the west of Huntsville is under threat from development (what else?). An open discussion debated the merits of petitioning the Fish & Wildlife Service to list the species under the Endangered Species Act. One landowner has most or nearly all of the habitat the species needs, which is a very specific form of spring flow running through what's essentially a flooded forest/field swamp system. This guy apparently thinks his property is worth $33 million which is hugely inflated. He's been talking to FWS for over 30 years about this situation, at least acting like he's willing to cooperate in protecting the species on land that's been in his family for a while. But now much of that area has been re-zoned for high density development, and a developer has opened an office in a nearby former cotton gin that was essentially an abandoned building in recent years. It's a complicated story that needs to be told in better detail, but in short my impression is that this guy is playing the feds & state people, playing for time until the area is being developed at which point it's too late for the fish. So most people present were of the opinion that it's better to get listing for the fish rather than pussyfoot around with this guy as he attempts to do his clever country boy shuck & jive. I agree.

We also talked briefly about flame chubs. Jim Williams was present who did many of the original collections of the species in the 60s and 70s that I was attempting to re-verify in my survey. He was at first doubtful that the species is really disappearing, but several of us prevailed on him and I think he was changing his mind as he thought about it. I hope so, I respect his opinion.

Saturday, November 07, 2009

Stippled Studfish Abstract For Talk At Departmental Retreat

I'm setting myself up for a strangely busy week this coming Wednesday through Sunday. I hope to be able to meet with others in Guntersville, AL, for an informal Alabama Imperiled Fishes Group meeting on Wednesday afternoon. On Thursday or Friday I hope to visit part of the Southeastern Fishes Council meeting at the same place in Guntersville. Saturday will be a short talk on what I've found with stippled studfish at our department's retreat at Wheeler State Park to the west of Huntsville. And on Sunday we're going to Estill Fork for our monthly dark-of-the-moon driftnetting, and one last monthly collection of telescope shiners for gill fluke examination. And I don't plan to miss teaching any classes, either.

So here's the Abstract of the talk I'll give on Saturday:


Looking for Stippled Studfish in the Tallapoosa River System

Bruce Stallsmith
Department of Biological Sciences
University of Alabama in Huntsville

Many fish species in the southern United States are under threat, facing an increasingly imminent threat of extinction largely from habitat degradation. One such species is the stippled studfish, Fundulus bifax, endemic to the Tallapoosa River system of Alabama and Georgia. The requisite habitat for this species is clean water over clean sand in small or large streams. The species has apparently vanished in Georgia, and appears increasingly uncommon in Alabama. This has resulted in a global ranking of G2, Imperiled, from the Nature Conservancy. Twenty six Tallapoosa River drainage sites in Alabama were visited in 2008 in an effort to document the current status of this species. Many of these were locations where the fish has been collected since 1980, as documented in the University of Alabama Ichthyology Collection. At least one individual was found in six different creek systems in Coosa, Elmore, Randolph, and Tallapoosa counties. This is a contraction of what has been considered this species’ range, and appears to be the result of habitat degradation. The future of the species is in doubt with six disjunct populations being vulnerable to further habitat degradation and diminished gene flow.

Thursday, November 05, 2009

I Submitted The Flame Chub Manuscript, For Real

I wasn't sure I had to do it, but apparently I did, so I formally resubmitted the flame chub manuscript to Endangered Species Research today. This involves creating an account at their web site, submitting a separate cover letter with three possible reviewers, naming an editor for the manuscript, and submitting the manuscript itself, all as .pdf's. So it's done.

My intro biology classes were some kind of amused when I told them about Octomacrum lamiaruthis. What can I say, it's real biology.

Tuesday, November 03, 2009

Meet A Newly Named Species of Monogenean Gill Fluke

This is a markedly different type of gill fluke that Taito and Andrew found and ID'd in a telescope shiner. The animal is visible to the naked eye at about 3 mm long, compared to the Dactylogyrus species we've seen at about 300 micrometers long (a tenth as long). It's definitely in the genus Octomacrum, which currently has 7 or 8 known species who parasitize various suckers or cyprinids. Don Cloutman at Bemidji State confirmed our genus ID. He also said he'd never seen it on a telescope shiner. We're convinced that it is a new, undescribed species, so I have a proposed binomial for it: Octomacrum lamiaruthis, with the specific name meaning "Ruth's vampire" in Latin in honor of my wife, Ruth Fledermaus. The vampire reference reflects the feeding strategy of gill flukes, which consume blood and other fluids through a wound they make in a fish's gill filaments. And thanks to Stephen Sansom at UNC for the correct Latin structure for the name.