Friday, June 29, 2012

Silver Shiner Juveniles, I Think

We've been to the Flint River at Oscar Robertson Road twice this week, Monday and Friday. On Monday we found a single adult silver shiner, and none today. But each time we found 6-7 apparent juvenile silver shiners. They look pretty similar to scarlet shiners at first glance, but they have much bigger eyes and an obvious lateral stripe somewhat buried in very bright silver color. These are the first juveniles of the species we've found. The adults have become really scarce, but this is an interesting twist.

The river is so low now that some of the locals who show up at the site to use it as a beach are driving across the riverbed and parking on the now very large gravel bar. I guess they do it because they can... It also seems to be a popular thing to leave amazing amounts of trash behind including used diapers. I'm sure those people would bitterly resent it if I pointed out the errors of their ways, but Jayzus - it's like redneck culture run amok. I'll post pictures later, but not, I promise of used diapers. Feh!

Tuesday, June 19, 2012

Ichthyology Class Trip To The Flint River Today

Today's lab exercise for my Ichthyology class was taking the class out to the Flint River at Oscar Patterson Road, NE of town. Last time I was there in March the water was high and fast, just low enough so we could do some seining and castnetting. Today, no problem; a few deep holes but nothing life-threatening. Eight students made the trip, some of them below just after we arrived.

We found a more interesting range of fish than I would have guessed. We netted one Silver Shiner, always a good sign. The surprising part was that we found 2, maybe 3, species of Cyprinella--Whitetails (galactura), Spotfin (spiloptera), and maybe Steelcolor (whipplei). I have to look at the ones we kept sometime tomorrow and see if some of them really are Steelcolor. All three are in the Flint, I'd just never encountered three Cyprinella species in one small stretch of the Flint. Below is a picture of the river stretch we found the fish, primarily under or just downstream of the bridge in flowing, knee-deep water over exposed flint bedrock and some sand and cobble.

Monday, June 18, 2012

Silver Shiner / Banded Darter Manuscript Close To "In Press"

I've been re-working the short manuscript I submitted to Southeastern Naturalist along with Brian. I did a last few minor edits today, and Don the editor thinks it's good to submit to the chief editor for final approval. We changed the title of the manuscript to "Observations of Notropis photogenis (Silver Shiner) and Etheostoma zonale (Banded Darter) in the Flint River, Alabama" since we weren't strictly the first to find the species, more like the first to more broadly write about it. I added in some material about the condition of the Flint River, for instance, it's still rated as too turbid by the EPA, and has until very recently been rated as facing eutrophication stress, and being prone to sharp spikes of fecal bacteria. So the fact that the Silver Shiner, in particular, is still in the river is kind of touch and go in terms of habitat degradation. As the odd quirk of the month, we have collected 36 Blotched Chubs out of the Flint this month, and 30 of them are male. Huh? We're trying to figure out what this means, if anything. And we still need to collect some Silver Shiners, we almost caught some on Friday but they kept bouncing out of the net.

Wednesday, June 13, 2012

OK, Time To Post More

I've been distracted over the past several weeks by going to Panama for 2.5 weeks, and then coming back and immediately starting summer school. But now I have the right focus. Panama was great, I collected populations of the livebearers Brachyrhaphis terrabensis, B. roseni and Poeciliopsis turrubarensis in the western provice of Chiriqui, from sea level up to 1265 m above sea level near Boquete. I hope to describe their gill parasites, and determine what distribution patterns might exist of parasites to the various hosts by species and elevation in the Rio Chiriqui basin. That's not Alabama, of course, and we're still working on projects with silver shiners, scarlet shiners, blotched chubs and snubnose darters. The big surprise of the season was finding female silver shiners in February with huge, well developed ovaries, much earlier than is typical of other local cyprinids. We still haven't done full maturation assessments or count ova, but it's different from what I would have expected. Here's a photo of one the best spots for B. terrabensis, a fairly large species found in highland streams that are clear and cool. This is the Rio Chiriquicitos, just downslope of the Reserva Forestal Fortuna where we stayed. This site is about 680 m above sea level.