Jon Michael Mollish

Fisheries Biologist | Knoxville, Tenn.

Forget Career Day. Jon Michael Mollish found his calling when he walked across his backyard and yelled, “Hey, what-ch’all doin?” A TVA crew was probing the Little River with corded wands that connected to their Ghostbuster-like contraptions. Had the group ignored the question — or not ventured to Maryville, Tennessee, that morning in 2006 — Mollish doubts he’d be making his living in a pair of TVA waders today.

The posse of fisheries biologists allowed the young environmental studies major to job shadow a fish survey. The day’s highlights involved temporarily stunning a variety of fish species with an electric field in order to determine the overall health of the stream, but it also led to a five-year mentorship that gave Mollish the ability to interpret nature’s story through science.

In 2012, the team officially christened Mollish as a staff fisheries biologist. They gave him his own electrofisher to study non-game fish in the streams, rivers and shallow-water tributaries that ripple across the Valley.   

“I’m all about the little fish,” he said. “Darters and minnows are my thing.”

Tennessee River Awesomeness

Outside of the tropics and rainforests, the Tennessee Valley is one of the most bio-diverse regions in the world. Mollish likes to talk about this truth and how the Volunteer State has the most species of fish in the nation.

He’s full of brainy fun facts too, like how some dragonflies spend their first two years living underwater. The textbook explanation has something to do with larval stages, which the biologist often likens to a caterpillar’s journey toward becoming a butterfly — except this one is vicious. Once the submerged larvae morph into dragonflies, they go airborne and turn into the “baddest bugs in the stream.”

Mollish can talk in terms of bio-buzzwords and community-fish assessments, but for the laymen, “the plain awesomeness of the Tennessee River boils down to the little darters, minnows and other small fish that mainly reside in the tributaries.” If these fish are missing from the river, there’s a likely reason — dirt.

Mudding the World's Waters

Sedimentation is the most common river pollutant in the world. It’s caused by erosion, which is often spawned by deforestation and poor land-use practices. In other countries, sedimentation has not only decimated once-thriving ecosystems, but has directly affected human health.

Although most Americans understand that clear-cutting large swaths of rainforests can create problems, few realize that sediment pollution is not isolated to the Amazon. Muddy waters pose the same threat here in the Valley as they do abroad. The issue is one that Mollish believes requires more education so communities can better protect the natural resources in their own backyard.

The good news is that environmental professionals like Mollish try to keep things in check. TVA and other federal, state and local agencies develop programs and initiatives designed to prevent extensive water-quality issues like sedimentation.

“Having that vegetation buffer on the sides of our riverbanks is so important to maintaining healthy streams,” Mollish said. “It’s like a sponge. When runoff and pollution hits it, it’s either slowed down or sucked up. The vegetation essentially serves as a natural filter.”

Mollish sees the benefits of this ordinary purifier through something called the Index of Biotic Integrity. The IBI is a sampling methodology TVA developed in the 1980s to assess stream health through the annual surveys of fish and aquatic communities. The system allows the agency’s biologists to identify and track water-quality issues, both positive and negative, throughout the Tennessee River watershed.

“Those fish tell me what’s happening in our rivers. If I survey an area and notice fish-X is missing but fish-Y is there in higher numbers, it may point me to a particular type of pollution. That’s why studying our fish and aquatic insects is so important. The science gives us the ability to raise the flag and hopefully correct water-quality problems before they ever have a chance to become a public health concern.”

His Next Adventure

Mollish’s hobbies aren’t much different from his daily work routine. Boats. Nature. Travel. But when the Tennessee Valley’s elaborate 650,000-acre waterpark is part of an everyday grind, sometimes it takes more exotic destinations to quench a thirst for adventure travel.

His passport stamps prove it. The man’s been places.

He’s toured Iceland in a camper van, sailed from Panama to Colombia, whitewater rafted Patagonia and spent five days floating the tailwaters of Victoria Falls in Africa. But Mollish didn’t have a sizeable trust fund or a mystery inheritance to finance the trips. He “roughed it” with his lifelong buddies — sometimes for as little as $50 per day.

Perhaps Mollish’s next vacation will be different. He’s adjusting his honeymoon plans due to COVID-19, but that’s not stopping his matrimonial plunge. He and his fiancé, Brittany, are set to exchange vows on New Year's Eve. Brittany teaches pharmacy at South College in Knoxville, Tennessee.

Mollish graduated from Eastern Kentucky University in 2009. He holds a Bachelor of Science in the field of environmental studies. His work is part of TVA’s Valley-wide initiative to build a stronger, more sustainable future. To learn more, check out the 2019 Sustainability Report.

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