Little-Winged Pearly Mussel

An Endangered Species

So... What Is It?

Well, scientists use their smart people term for the species as Pegias fabula, but I'm going to call it a little-winged pearly mussel. Well, the animal is pretty small, & not much of its life history is known. The shell’s outer surface is usually eroded, giving the shell a chalky appearance. When the outer surface is present, the shell is light green or dark yellowish with dark rays. The species is thought to be a winter breeder and reproduce like other freshwater mussels. The specific food habits of these mussels are unknown, too. But, adults are filter feeders and likely eat food that other freshwater mussels do (organic detritus, diatoms, phytoplankton). So, we know a lot about this creature, but it's not too special. Ah, you'll find why you are wrong!

Image Source: www.fws.gov

Distribution & Habitat

The little guy inhabits cool, clear, and relatively high gradient streams (of small to medium size), so it's safe to assume that this species would not like a polluted stream. This is where it's sometimes found lying on a rocky stream bed in shallow water. Most of the time, because it's too shy, it's found hidden under large rocks. No wonder we don't get much information on this guy. He's never available for comment to the press!

Once upon a time, the little-wing pearly mussel was widespread over many smaller tributaries of the upper Cumberland and Tennessee River basins in Alabama, North Carolina, Kentucky, Tennessee, and Virginia. Then, everything changed when the Fire Nation attacked. It's now left to the ava- sorry.. erm, three populations may still live in the Cumberland River system & three in the Tennessee river system, including a very small population in the Little Tennessee River, North Carolina. The map above only shows three populations survive in three counties, including Swain, Macon, and Cherokee County.

Image Source: www.fws.gov

Why Is It Endangered?

Like I said, you can imagine that this little guy only likes clean, cool, and non-polluted water. Well, poor water quality and habitat conditions are the main threats for the little-winged pearly mussel. Dams, channelization projects, and in-stream dredging operations directly kill off their habitat. This is why I don't support hydroelectricity; it limits biodiversity. Water flow, temperature, and chemistry are three big factors that are altered in these man-made operations that hurt a little-winged pearly mussel. Agriculture & forestry operations, roads, residential areas, golf courses, and other construction activities that don't control soil erosion and water runoff give off huge amounts of silt, pesticides, fertilizers, heavy metals, and other pollutants that suffocate and poison freshwater mussels. I hope you're happy killing a freshwater mussel using that much road salt, ;-; Anyway, changing up floodplains or removing forested stream buffers can be very costly to the population. These help maintain water quality and stream stability by absorbing, filtering, and slowly releasing rainwater. This also helps recharge groundwater levels and maintain flows during the dry months.

You thought it was over? No, we humans don't stop there. Acid mine drainage and other water quality detriments associated with gas, oil, and mineral extraction also help the destruction of this freshwater mussel population.

Image Source: www.carolinapublicpress.org

Well, why should I care?

Mussels are always filtering the water for food and oxygen. In this process, they clean the water of pollutants and large quantities of organic particles, much like a tiny water purifying system. They play a huge role in the aquatic food chain as a food source for wildlife, including river otters and muskrats. Their shells provide protection and a nesting habitat for aquatic insects, crayfish, and bottom-dwelling fish species like darters, sculpins, and madtoms.

Image Source: www.ncwildlife.org

Ok, I care! But now what?!

Well, I've got Unswaggy Stan, Swaggy Sam's bro, to get the low-down on what's being done to protect this endangered species. He works for the U.S. Fish and Wildlife Service (so unswaggy). Take the floor, Stan!