Friday, April 13, 2018

An epic aquatic foray

A dream team crew of aquatic biologists seines for fish in Little Darby Creek in southwestern Franklin County, Ohio. After two reschedulings due to high water, yesterday's foray was perfect in every way: temps in the 60's-70's, blue skies, and perfect water levels. While I was the prod to get this trip afoot, great thanks to Anthony Sasson of the Ohio Chapter of The Nature Conservancy for his organizational efforts and tapping the involvement of the likes of Brian Zimmerman, Andrew Boose and other authorities on aquatic fare. I will take credit for getting the incomparable Laura Hughes to join us :-)

With this crew, we were assured of all manner of underwater wonders being found, and that's exactly what happened. It was one of the best days of aquatic exploration I've ever been part of. Ten species of darters were found (we missed two that are known from this locale), plus many other fish species. Lots of non-fish aquatic organisms as well.

This spot in Little Darby Creek is owned by Franklin County Metro Parks, as part of the sprawling Battelle Darby Metropark. Metro Parks deserves enormous credit for conservation efforts along the Darby Creeks, as does the Ohio Chapter of The Nature Conservancy. Big and Little Darby creeks are exceptional warm water habitats and rank high among the finest streams in the Midwestern U.S.

Perhaps the showiest fish in our streams, the gaudy rainbow darter, Etheostoma caeruleum. This is a male in breeding colors, which they obtain and hold for a fairly brief period in early spring.

Note the peculiar lips on this male banded darter, Etheostoma zonale. This is another male in breeding colors. Darters are small members of the perch family, and lack swim bladders. They spend their time on the bottom substrate, rooting about for small animal life.

The pointed nose of this logperch darter, Percina caprodes, serves as a shovel of sorts to aid it in pushing pebbles around to uncover prey. Logperch are comparatively elephantine in regards to other darters, with hefty individuals reaching seven inches. Most of our other species are perhaps half that length.

A barred fantail, Etheostoma flabellare, offering a good view of its namesake tail. This small species is common in clean rocky riffles such as where we were working yesterday.

A small feeder stream entered Little Darby not far from our base camp of operations. A foray into that netted (literally) a few species that are mostly confined to small streams. This is one of them, an orangethroat darter, Etheostoma spectabile. This is a male in breeding colors. It's similar to the rainbow darter, and hybridizes with it, but differs in the conspicuous orange throat, completely aqua-blue anal fin (lower fin just before tail), among other differences.

A personal favorite, the gargoyle-like mottled sculpin, Cottus bairdii. These little predators become one with the rocks, hiding among stones on the stream bottom and lunging at passing prey.

Upon returning to base camp after following the survey crew upstream for a while, I arrived just as Laura Hughes found a stunning species of turtle. She's got it in hand in this shot, and I showcase the reptile in the following photo.

We lug our camera gear and other implements afield to make these shots. A small table on the gravel bar provides a stable platform. Several small aquariums stand ready to receive photographic subjects. The reasons for setting up operations streamside are at least threefold: 1) It's just easier to have everything so handy to the working site; 2) fishes in breeding condition lose their colors fairly quickly when removed from the stream and the exact water temperature which stimulated the coloration, and 3) we don't want to harm the subjects. By seining fish in close proximity to the photo operation, we can quickly release them back into the stream, where they were captured.

There's much more to making good fish photos, but I'll not bore you with details. Shooting into aquaria and through water, especially with flash, involves lots of nuances and efforts to keep water clear and tank sides clean.

Here's Laura's capture, a common map turtle, Graptemys geographica. This one must have been a female based on her size - they get much larger than males. By placing the turtle on the moist edge of the gravel bar, she gave us lots of photo ops. I was pleased to have the chance to create imagery of this species. Map turtles are incredibly wary, from my experience, and your mere appearance causes them to drop from basking logs and rocks before getting anywhere near the animals.

Another cool thing about map turtles is that they feed often on clams, which gives an indication as to their jaw power. Probably good to keep fingers away from those mandibles, although the turtles do not act particularly aggressive.

We found this rusty crayfish, Orconectes rusticus (I think; as always identification corrections are welcome), a female with eggs. Click the photo to enlarge and you'll better see the egg mass, which she carries under her tail. A protective mother indeed!

One of the seine hauls captured this cool little damselfly nymph, of an ebony jewelwing, Calopteryx maculata. Damselfly and dragonfly larvae are strictly aquatic and mostly out of sight and mind. The winged adults are often highly conspicuous.

It wasn't all wee fish. The survey crew brought up this fine specimen of a smallmouth bass, Micropterus dolomieu. It, of course, was released unharmed. The Darby Creeks are known for hosting good bass populations.

Finally, I'll end this fishy foray with one of our coolest catfishes, the stonecat madtom, Noturus flavus. There are five extant madtom species in Ohio, and this is probably the most common and widespread. Another, the Scioto madtom, Noturus trautmani, is perhaps Ohio's most fabled fish. It was only known from a handful of captures in Big Darby Creek, and is now considered extinct. The last captures date from 1957.

Madtoms are notable for their pectoral fin spines, which are armed with venom sacs at the base. Incautious handlers might receive a painful sting.

Thanks to everyone who was part of this expedition! It's always great to get afield with people who are not only top experts, but are passionate about their subjects, and conservation.

3 comments:

Lisa Greenbow said...

This was so much fun. I love seeing what I don't normally get to see. The photo of the crayfish is outstanding. Seeing all of those eggs is impressive.

Jim McCormac said...

Thanks Lisa! I always appreciate your comments!

Mael Glon said...

You're correct on the rusty crayfish, but the genus was recently changed from Orconectes to Faxonius. I work on crayfish at OSU and would be happy to sample with you if you ever want to get more species. A really pretty species, Cambarus polychromatus, can be found in burrows along the banks of Darby.

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