First off, I'm a transplant to this part of the country and this is only the 2nd time I've actually gone out looking for a species of fish (I'm a herp and invert guy). I did not have a seine, but was really just sightseeing and casually sampling waterways with a cheap bait net from WalMart! The goal was really a nice roadtrip, but the bonus would be additional specimens of the Red River Pupfish. The Red Hills are a pretty strange place to me, like a little slice of reddish southern Utah but with saline rivers and creeks due to the mineral deposits and extensive gypsum beds. I'd say the fish fauna is pretty sparse overall due to the salinities, pH, temps, and unreliable flow. In any case, it's probably not what most people would expect from Kansas.
The first stop was along the upper Salt Fork of the Arkansas River. At this point, the river is pretty small (5-10 ft across, 3ft deep) although water levels were high compared to when I was here herping late last spring. The water registered ~2ppt salinity. I swear I once clearly saw the flash colors of a male pupfish here in a shallow side pool, but to this day I have no solid evidence of them here.
I caught tons of Northern Plains Killifish here, and a couple exceptional specimens I kept for the rudimentary Red Hills tank idea I've got rolling around in my head. Caught a few other species here too, which I'll add to the total list at the end. But no pupfish...I guess they're not here.
I spent the better part of 3 or 4 hours zig-zagging back and forth across dirt roads, snapping landscape photos, hiking, and swiping various streams like this one. Some had nothing, some had a lot, and I didn't see a whole lot of logic in the why and why not.
Beautiful clarity, but as luck would have it, the only thing here (or catchable with my net) was Gambusia, which I'll spare you the photos of...
I finally reached some upper tributaries of the Cimarron River, a notoriously saline river, to which pupfish have been introduced. But waaay upstream here the salinity was only ~1ppt. It took about 20 minutes, and sorting about 500 Plains killiefish, but I did net around 20 pupfish, of which I kept 7 subadults. I was hoping to find them in this low of a salinity in hopes of having a little better luck with them in the home aquarium. Due to their small size, the photo is from a home tank...
Since I was in the general area, I decided to go ahead and head south to Oklahoma to visit my first pupfish collecting site on the Cimarron River and see a couple of the nearby state parks. Here the salinity level was off the chart on the cheap brackish hydrometer I brought...I'm guessing in the 22-25 range. I read that salinity levels have increased dramatically in the last century due to agriculture and groundwater pumping. I can't overstate what a desolate, bizarre, and surreal ecosystem this is...a salt river. It's much like the aquatic equivalent of a desert. If any forum folks ever get out that way, check it out. It makes me wonder what the fish-eating herps do there, like turtles and watersnakes, with no evolved salt excretion capabilities. There was no more netting all the shiners, minnows, and killifish of some of the previous sites. In fact I barely saw any fish at all and the one small school that I did see was out of reach of my net (probably plains killifish). All that the net produced was one large, dead pupfish.
The banks and close vegetation are totally encrusted with salt and choked with invasive tamarisk.
Other fish found in no particular order or collection site:
Emerald Shiner Notropis atherinoides
Green Sunfish Lepomis cyanellus
Plains Minnow Hybognathus placitus
Fathead Minnow Pimephales promelas
Arkansas Darter Etheostoma cragini
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