Visual Ecology of Lake Erie Walleye with Andy Oppliger

My name is Andy Oppliger, I was fortunate enough to spend my summer at Stone Laboratory studying how turbidity (i.e. suspended particulates in the water column) alters the visual ecology of Lake Erie Walleye (Sander vitreus). The ability of an animal to distinguish between an object and its background (i.e. visual sensitivity) is expected to be altered by increasing turbidity due to both decreased light penetration and a change in the color of light underwater. My objective is to determine if varying turbidity types – algal or sedimentary – differentially influence visual sensitivities of adult Walleye. To determine how visual sensitivity is impacted by turbidity, an optomotor response apparatus was constructed (see photos below) to establish visual thresholds. This study contributes to our understanding of how Walleye populations may respond to changes in Lake Erie’s turbidity.



Meet our new PhD Student- Bethany Williams

This summer I had the opportunity to spend a pre-enrollment field season in Uganda to prepare for my PhD in the fall. Our field station was set on stunning Lake Nabugabo, nestled against a rural fishing village. Days on the station were spent driving or boating to swamps where we collected a species of cichlid, known in the lab as Blue-Lips (Pseudocrenilabrus multicolor). This cichlid is easily recognizable by its namesake bright-blue lips and ability to survive in various extreme conditions. While on station I ran behavioral experiments testing whether water turbidity affects female mate choice when given the option of a male from her population or a male from a population with differing turbidity. My PhD will investigate the physiological and behavioral traits used by this species to survive in stressful environments.



AFS Buckeye Student Subunit Passport to Fishing Event

Over the weekend, the Gray Lab helped out with a passport to fishing event hosted by Wade Hall at Cowan Lake State Park in Wilmington, OH. It was calling for storms, so there wasn’t a huge turnout, but the children that did come all got to go home with new fishing knowledge and new fishing poles so they can continue to fish in their free time! Topics discussed were fish habitat, knot tying and rigging, casting and fish handling, as well as some useful information about local fish species and fishing regulations. The kids had a blast and we learned a lot too! Can’t wait until we can host our own AFS student subunit Passport to Fishing event in the spring!  

Gray Lab Summer REU Student- Harrison

My name is Harrison Fried, and I am studying the effects of algal turbidity on the swimming performance of Emerald Shiner (Notropis atherinoides) and Golden Shiner (Notemigonus crysoleucas). Agricultural runoff leads to large amounts of phosphorus and nitrogen that enter the Lake Erie watershed, which can create massive algal blooms. Fine particles from the algae can enter the gills of fish and cause gill abrasion, making it difficult for the fish to respire. The swimming performance tunnel, as shown in pictures, is used to measure the critical swimming speed of a fish (the maximum speed that a fish can swim for a set period). The goal of my study is to determine whether swimming performance is different in algal blooms than in clear water.


13th International Congress on the Biology of Fish

Come out and see the Gray Lab if you are headed to the ICBF Conference this upcoming week! Dr. Suzanne Gray presents her research on the visual detection thresholds in walleye and their prey in algal and sedimentary turbidity in MacEwan Hall A on Tuesday, July 17th at 2:40 pm. Followed by Chelsey Nieman at 3:00 pm in MacEwan Hall A discussing her research on visual performance being impaired by elevated sedimentary and algal turbidity in Walleye (Sander vitreus) and Emerald Shiner (Notropis atherinoides).  Tiffany Atkinson discusses the role of turbidity and diet on the reproduction traits of an African cichlid fish during her talk in the Bianca presentation room on Thursday, July 19th at 10 am. And lastly, Richard Oldham gives his talk on divergence in visual performance and morphology in an African cichlid found in divergent environments on Thursday, July 19th at 2:20 pm in the Bianca presentation room. Come out and listen!

Water Across the World 2018- A note from Tiffany

One of my favorite parts of visiting Uganda is getting to work with local primary schools with our Water Across the World project. This project aims to teach students the importance of wetlands, forests, and aquatic organisms, and the role they play in water quality. This year we worked closely with the students and teachers from both St. Hildegard Primary School and the Lake Nabugabo Community Learning Center. They were all very excited to have us back to explore their water sources. We have also arranged the program to continue throughout the year, not just while we are there doing our fieldwork. Our amazing field staff, Mutebi, Kiberu, Ssegoya, and Geoffrey, will be working with these schools frequently so that they can begin to compile longer-term data from their local water sources. Some of the data they collect include: temperature, flow, water color, turbidity, and aquatic macro-invertebrates. I hope that by engaging students in this experiential learning process, I might be able to inspire some to become future scientists!

-Tiffany Atkinson


Zane State Natural Resource Center with Water Across the World

We spent yesterday with Nicole Hafer and her Muskingum Soil and Water Conservation District’s summer camp students! We have been working with these students for about four years now with our Water Across the World project where we connect them with grade school students in Uganda through videos and letters. Yesterday, we got to teach them a bit about water quality and aquatic organisms in the US as well as Uganda. We even had them lift a Jerri can to experience what retrieving water is like in Uganda vs. just turning on your tap at home. We also talked about the microsystis blooms that are currently plaguing Lake Erie and how it can affect Ohio’s water quality. Afterwards, we got to sample stream invertebrates and do a little fishing! Thanks so much Nicole and students for such a great experience!

Field Season is in Full Swing!

We currently have Jeremy sampling differently managed agricultural ponds for water quality and fish and macroinvertebrate biodiversity; Bethany just returned from Uganda where she was investigating mate-choice between two populations of cichlids; Tiffany has been working on her cichlid diet analysis; Shib is dissecting eyes and brains of Round Gobies to look for parasites that cause cataracts; Chelsey is working closely with Lake Erie Charter captains to determine lure color choice of Walleye in different water conditions; Taylor has now reared 400 cichlids in the lab for behavioral studies under turbid and clear conditions; Andy is studying the optokinetic response of large Walleye under turbid conditions at Stone Lab; and Harrison is studying the swim performance of Emerald Shiners at Stone lab for his REU project. Quite the busy summer for the Gray lab! Stay tuned for weekly research spotlights on each project!

First Gray Lab Publication!

Congratulations to Richard Oldham who just had his first paper accepted in Current Zoology, “Behavioral differences within and among populations of an African cichlid found in divergent and extreme environments”. Richard performed this experiment as an undergraduate Research with Distinction project with The Gray Lab and The Pintor Lab!