Missouri Department of Conservation Fisheries Biologist Dave Knuth observes a Paddlefish in the Diversion Channel near Cape Girardeau.
Ever wonder why some of our native species look like they came from another planet? The thought crossed my mind this week when I was out on the Diversion Channel with Fisheries Biologist Dave Knuth and got an up close look at a Paddlefish. Locally known as a Spoonbill, the designation as Missouri's official state aquatic animal automatically grants the fish some respect. But when I examined the Paddlefish I couldn't help but marvel at how odd it looked.
Named after its flat, elongated nose, this fish is something to behold. Its nose, or rostrum, takes up almost a third of its total length and appeared as if it would cause the fish to struggle just to stay level in the water. But apparently this fish's nose is more high tech than it looks. Biologists used to believe the fish used their long snouts to dig up vegetation from the bottom of a waterway. But on further investigation, they learned that the fish filter zooplankton from the water using filaments on their gill arches, which are quite large.
The long nose is full of receptors that cause it to act as an antenna able to detect zooplankton. It also helps to stabilize the fish while it swims through water with its mouth wide open. According to Wikipedia's files on Paddlefish, that long nose works just like the wing of an airplane and actually creates lift for the fish. So even though it looks like that snout could weigh the fish down, it actually helps to keep its head steady while the fish has its swim-through meal.
Paddlefish are found commonly in the Mississippi, Missouri and Osage rivers. They can live 30 years or more and reach up to 60 inches long. They live mostly in open waters of big rivers, swimming continuously near the surface, and likely don't have a specific home range. As waters rise in spring, paddlefish move upstream to gravel bars to spawn. They need lots of open, free-flowing rivers plus oxbows and backwaters for feeding and gravel bars for spawning, according to the Missouri Department of Conservation (MDC) website. Ecologically, they add value to our rivers by keeping populations of aquatic organisms in check and providing food for their predators.
Although they are highly prized sport fish, their numbers are declining. Diminishing habitat continues to reduce Paddlefish numbers, requiring MDC to closely monitor the population. According to the MDC, impoundments hold the highest populations of paddlefish today, but because many of these lack feeder rivers that meet their spawning needs, these populations are not self-sustaining and are often stocked. The closest relative, the Chinese paddlefish is extinct.
The Paddlefish Dave and I saw was a small one, but the chance to see and touch such a respectable creature was thrilling. Even though I appreciate these Paddlefish just for their aesthetic value, I must admit there are much more important reasons to ensure we never find our state up the river without a Paddlefish.
For more information about Paddlefish in Missouri, go online to www.mdc.mo.gov.