This article was written by Jan Jeffrey Hoover.

No other fish in the Mississippi River is like the paddlefish. It is a living museum; a unique hodgepodge of anatomical oddities. And it is because of these peculiar features that the paddlefish is important – and valuable – to so many people and for so many different reasons.

The paddlefish provides naturalists with clues to the forms and habits of species that lived during the time of the tyrannosaurs. It is the sole survivor of a single group of ancient bony fishes. There was a second related species in China, but that fish has not been seen since 2003 and is presumed extinct. Our American paddlefish, however, is abundant and frequently observed in the lower Mississippi River.

It is quickly recognized by its asymmetrical tail and its prominent snout and specialized sensory organs. The tail is shark-like, with a large, muscular upper lobe, and a small, weaker lower lobe. The snout, and much of the head, is studded with thousands of numerous pores that detect weak electrical fields generated by the microscopic plankton on which it feeds. A third eye, on the top of its head, is believed to track annual changes in daylight and cue seasonal behaviors like migration and spawning.

The soft skeleton, composed mostly of cartilage, and the slick skin that is almost scaleless, makes the paddlefish easy to process, sell, and consume. In the early 1900s, after sturgeon populations crashed from over-harvest, paddlefish provided an alternative and readily exploited source of fish oil and meat. The oil was used in medicine, nutrition, and agriculture. The flesh, marketed as “boneless catfish,” was smoked. And then there was “black gold.” Like sturgeons, female paddlefish have large ovaries with eggs (roe) that ripen into the high-priced treat called caviar.

Paddlefish caviar from the United States has been acknowledged for more than a century as comparable in appearance and flavor to Beluga caviar from Europe. Beluga, the gold standard of caviar, currently sells for hundreds of dollars an ounce, but domestic paddlefish caviar retails for a comparatively modest $21.25 an ounce. Although considerably less expensive, a single large female paddlefish like those from Mississippi River backwaters and oxbow lakes containing 10 to 15 pounds of roe, is worth $3,500-$5,000. It’s no surprise then that paddlefish are sometimes the target of poachers and overzealous fishers. Over-fishing, though, is just part of the reason for declining populations of paddlefish outside the lower Mississippi River.

Although not listed as a federally endangered species, some paddlefish populations are imperiled by blocked migration routes, environmental degradation, and invasive species. Research at the U.S. Army Engineer Research and Development Center (ERDC) identified high-crest dams, dampened river flows, and invasive carps as significant impacts to paddlefish populations.

Still, paddlefish are surprisingly rugged and extremely motile. One specimen was rescued by ERDC biologists in the aftermath of the 2011 flood when it had passed through the Bonnet Carré water diversion structure in south Louisiana. The paddlefish not only survived, but when returned to the Mississippi River, traveled 390 miles to Greenville, where it was recaptured and released by a commercial fisherman.

Paddlefish are highly dispersive. A collaborative tagging study conducted by ERDC, the University of Mississippi, and the Mississippi Department of Wildlife Fisheries and Parks showed paddlefish from an Oxbow Lake in northwest Mississippi traveled up to five-and-a-half miles a day, 870 to 1,500 miles, in three different directions: north to the Middle Mississippi River; east into the Ohio River; and west into the upper Missouri River.

ERDC research has also shown that the enormous but remarkably light rostrum of the paddlefish is extremely resilient. Two struts that attach it to the base of the skull reduce the force of water flowing across its surface. And hundreds of feather-weight, star-shaped elements made of thin cartilage, are capable of dispersing traumatic forces, minimizing damage to the fish’s sensitive snout from forceful collisions with underwater objects. Engineers are now using the paddlefish as a model for designing bio-inspired materials, fabrics, and armor capable of reducing destructive impacts of projectiles and erosive forces to protect structures and personnel in natural disasters and wartime.

Insights into a distant, prehistoric past; a source of fish oil, boneless filets, and caviar; and a living example of lightweight damage-resistant structures for developing futuristic protective materials. What other fish in the Mississippi River can provide all that?

About the author: Jan Jeffrey Hoover is a resident of Jackson. Prior to retirement, he was a longtime employee of the U.S. Army Corps of Engineers (ERDC). He also taught courses in Wildlife Biology, Ecology, and Evolution at Mississippi College and Millsaps College. He can be reached at hooverj@bellsouth.net.