Rare Aquatic Species Found at TWRA's Benthic Blitz!

TWRA biologists recently wrapped up their second annual Benthic Blitz, an intensive survey of aquatic life across 123 sites within 10 watersheds of the Upper Cumberland River Basin, including the Caney, Collins, and Calfkiller Rivers. This large-scale effort helps fill critical data gaps and supports wildlife diversity by focusing on rare bottom-dwelling species such as snails, mussels, crayfish, and fish. A healthy aquatic ecosystem depends on a rich variety of these organisms, making the blitz an essential tool for conservation.

This year's blitz led to an exciting discovery: a new, robust population of the Littlewing Pearlymussel (Pegias fabula)—an extremely rare species known to exist in only two river systems. Finding such a strong population opens the door to meaningful recovery opportunities for this federally endangered mussel.

Led by TWRA Biologists Brittany Bajo-Walker and Parker Hildreth, nearly 100 biologists from 28 partner organizations took part this year. Participants represented state and federal agencies, universities, non-profits, and consulting groups—making the blitz not only a scientific endeavor but a valuable opportunity for collaboration. The event allows biologists to explore new stretches of river, discover previously undocumented species, and strengthen relationships across partnering agencies.

Highlights from the Benthic Blitz Discovery

Biologists located 14 species of Greatest Conservation Need, two listed as federally endangered.

Over 74 benthic species and approximately 9,668 animals were observed:

• 15 cray fish
• Seven mussels
• 46 fish identified