Vanishing Veins of the Watershed

By Isabeau Dasho and Bob DiStefano | February 17, 2011
From Missouri Conservationist: Mar 2011

If most Missouri streams were in peril, would you notice? Fertile stream floodplains were the first home to our settlers and rivers were our first highways of interstate commerce. Streams water our crops, provide our livestock and wildlife with ample vegetation, transport grain and fertilizer, and give us clean water for drinking and bathing. We seek out streams during hot summers to fish, float, swim and chase crawdads. Much of who we are and what we do depends upon clean and healthy streams. But many Missouri streams have been clogged with silt, poisoned by pollutants and overrun by development. Part of the problem is that many of us might not know a stream when we see one.

There are three main types of streams: perennial, intermittent and ephemeral. The differences between these can be vague because they reside on a continuum of connectedness, like veins in a body. These water bodies are all intricately related and affected by each other.

Perennial streams maintain flow throughout the year except during times of extreme drought. Perennial streams are what most people envision when they think of streams. But these make up only about one-third of all Missouri streams. At the other end of the stream spectrum from perennial are ephemeral streams. Ephemeral streams are wetted only in direct relation to the amount of rainfall received in the watershed—no rain, no flow. Intermittent streams fall somewhere between ephemeral and perennial in size, but certainly not in terms of importance. Intermittent streams have wet and dry seasons, flowing with water during the rainy spring and fall and drying to an underground trickle with occasional shrinking surface pools during summer. When flowing, they average only about 10 feet wide and 7 inches deep. But what intermittent streams lack in volume they make up for in value. In Missouri, intermittent streams far outnumber and are critical to the health of perennial streams.


Intermittent streams are full of life. Even when they appear dry their water is flowing beneath the surface, invisible to any casual observer. These streams are teeming with hundreds of species of insects, snails, mussels and other invertebrates—a vital food source for larger amphibians, reptiles, fish, birds and mammals. Intermittent streams support large and diverse food webs throughout the year. They provide critical spawning and nursery sites for many species of commercially, recreationally and ecologically important fish. Their surrounding trees and vegetation often provide the only habitat for many important wildlife species, particularly in agricultural landscapes.

Intermittent stream residents are often specialists, having developed adaptations that allow them to fill unique niches within their ecosystem. Recent Conservation Department research found 36 kinds of invertebrates that occurred only in intermittent streams in our state. These little critters are adapted to the wet/dry cycle and cannot live in either perennial or ephemeral streams. For example, the eggs of some stoneflies sometimes remain dormant for several years until streams are rewetted. Some caddisflies have drought-resistant pupal cases.

Other organisms have also developed wet/drought life cycles. Missouri salamanders often prefer intermittent streams to perennial streams, burrowing into wetted stream bottoms when the stream dries. Many Missouri fish species find intermittent streams an ideal habitat for a portion of their life cycles; minnows, shiners, darters, sculpins and madtom catfish species migrate to stagnant, isolated pools as streams dry and feed on the abundant insect life there. The Conservation Department recently found that 111 intermittent study streams contained 85 different fish species, with an average of nine but up to 28 distinct species per stream. Common fishes included channel catfish, sunfish, black bass, goggle-eye, crappie and rainbow trout.

Some endangered and economically important species rely on intermittent streams for spawning and nursery sites, and many more species depend on these streams for critical stages in their life cycles. Missouri’s rarest crayfish species, the Mammoth Spring crayfish, occurs in only three streams in the state, two of which are intermittent. Reptiles, birds and mammals use the vegetated corridors around intermittent streams and feed on the abundant life within them.

Intermittent streams are not only tremendous meeting places for swimming, crawling and flying wildlife to gather, but their other functions are equally vital to wildlife and people. Intermittent streams recycle important nutrients and energy that sustain the biological productivity of downstream rivers and lakes, keeping fish populations healthy and strong. These streams recharge surface and groundwater supplies for our drinking, bathing, irrigation and industrial uses. This water recycling keeps our river and lake water-clarity high, ideal for sport fishing and other recreation. Intermittent streams help control floods by slowing flows and providing floodplains for floodwaters to disperse and recede faster. So, these small streams also hold critical economic value to our society.


Human activities often threaten intermittent streams, possibly because it’s easy to overlook their importance due to their small size and periodic dry conditions. However, scientific studies document that when intermittent streams are physically altered, their ability to perform the aforementioned services is often greatly diminished, even when engineers try to minimize impacts.

Improperly managed urban and suburban developments introduce silt and sediments through erosion, thereby choking these streams. Paving or lining them with concrete reduces their ability to prevent downstream flooding. Row cropping or manure and fertilizer application too close to intermittent streams introduces harmful silt and toxic ammonia, killing stream life and tainting downstream water supplies for wildlife and people. Removal of vegetation surrounding intermittent streams will cause siltation, destroy feeding habitat and shelter for wildlife such as raccoon, quail and deer, and decrease or eliminate the recycling of nutrients for downstream fish and wildlife. Improper gravel mining, in or around intermittent streams, degrades the fragile stream bottom habitat that supports so much life and can alter stream dynamics. Industrial run-off, dumped or piped into intermittent streams, also degrades habitat and kills wildlife. Water extraction for industrial or municipal use may totally dewater intermittent streams at times of the year when lingering water is critical to aquatic life.

Without clean flows, fish will cease to spawn. Without insect larvae to eat, amphibians will starve and birds will move to other locations, just as larger predators will find their food stores low. The many niche species that have adapted to this unique environment are so dependent on and restricted to intermittent streams that they face localized extinction when these streams are degraded. Intermittent streams are adaptable, but a combination of too many of these harmful practices can irreversibly damage their biodiversity.

Intermittent streams are crucial to Missouri, and not only because of the unique and important biodiversity that lives in and around them. These streams provide dozens of ecological services that benefit people, such as flood prevention and containment. They filter and store water that we use for drinking, bathing and recreation. They also hold water for agricultural irrigation and livestock. They provide water to the trees and vegetation that produce oxygen and sequester carbon dioxide, helping to combat harmful air pollution. Intermittent streams provide habitat for animals we love, and love to eat.

Streams have been Missouri’s legacy since before Meriwether Lewis and William Clark plotted their way up the Missouri River. And intermittent streams make up more than half of all miles of Missouri streams. Though these streams may go unnoticed by many of us, they are critical to the health of the downstream waters that we all appreciate and use. As long as we plan on continuing our weekend fishing and float trips, and our daily consumption of clean water, we need to conserve our smallest streams and maintain the balance of our natural world.

Join Missouri Stream Team

The Stream Team program provides an opportunity for everyone to get involved in stream conservation. Stream Team goals are:

  • Education—Learn about Missouri’s 110,000 miles of flowing water. Stream Team provides training and information to better understand our stream systems and the problems and opportunities they face.
  • Stewardship—Hands-on projects such as litter control, streambank stabilization, streamside tree planting, water quality monitoring and storm drain stenciling are all possibilities.
  • Advocacy—Those who have gained a firsthand knowledge of the problems, solutions and needs of Missouri’s stream resources are best equipped to speak out on their behalf.

Stream Team membership is free to any interested citizen, family or organization. You may adopt any stream or river of your choice. We can suggest streams if you like, or connect you with other Teams in your area. To learn more about Missouri Stream Teams or to find a membership form, visit

Don’t Dump Bait or Release Captives

Dumping the contents of your bait bucket or aquarium into Missouri’s waters could introduce a species that might cause irreversible damage to our aquatic resources.

Some of Missouri’s most severe problems with aquatic invaders are the result of species that have been transported only a few miles from one stream to another. Bait bucket introductions occur when anglers dump live bait into a water body from which that bait did not originate. Alternatives to dumping bait include:

  • Taking your bait home to use on a future fishing trip,
  • Offering it to another angler to use,
  • Dumping it on land far away from any waterway or
  • Placing it in a sealed container in the trash.

If a person feels they can no longer care for a captive animal kept in a private aquarium or pond, we recommend the following alternatives to releasing them into the wild:

  • Talk to a pet store owner or a hobby aquarium society ( They may be able to help find a home for your pet.
  • Give the fish or other animals to others who might wish to care for them.
  • Dispose of the animals in a sealed container. Your veterinarian may be able to help if you feel that euthanizing the animals is the most appropriate solution.

Missouri prohibits importing, exporting or releasing fish, amphibians, reptiles, mammals or any other form of wildlife unless specifically authorized by the Wildlife Code. Missouri’s Wildlife Code also establishes a list of “Prohibited Species” that may not be possessed in Missouri. This list includes snakehead fish, walking catfish, rusty crayfish and several species of snails. For a complete list see 3 CSR 10-4.117 of the Wildlife Code.

Inspect, Drain, Clean, Dry

Anglers play a critical role in preventing the spread of aquatic invasive species. Prevention provides the best short-term and long-term benefits to Missouri. Here are a few steps you can take to protect our waters.

  • Inspect your equipment, waders, boots, nets, boats, and trailers thoroughly and remove any trash, mussels or aquatic weeds before leaving any water body;
  • Drain water from buckets, sample jars, motors, live wells, bilge and transom wells, trailers and any other water from your boat and equipment before leaving any water body;
  • Clean everything with heated fresh water (like a car wash or pressure washer); and,
  • Dry everything thoroughly in the hot sun before using it again.

Landowners Care for Our Streams

The Conservation Department works with landowners to sustain healthy streams. To help with stream conservation, here are few things landowners can do:

  • First and always, protect stream banks and riparian corridors for both rural and urban streams. Maintaining dense and permanent vegetation (trees when possible and appropriate) is vital to the safeguarding of these streams.
  • Keep livestock from streams and eroding banks. Consider alternative watering sources, and use rotational grazing practices. To learn more, visit or contact your regional Conservation Department office (see Page 3 for phone numbers).
  • Minimize field runoff by maintaining or restoring native vegetation along streams, using well-designed stream crossings, and maintaining septic systems.
  • Do not drive ATVs directly into stream channels.
  • Limit the use of pesticides and herbicides around homes that border streams.
  • Harvest stream corridor trees with the advice of a forester.
  • Support and participate in programs aimed at protecting stream corridors. Examples include the Natural Resource Conservation Service’s Conservation Reserve Program and the Stream Team Program.

These are some of the ways we can all become involved in protecting our valuable Missouri Streams. To learn more about stream management, visit or contact your regional Conservation Department office (see Page 3 for phone numbers).

This Issue's Staff

Editor In Chief - Ara Clark
Managing Editor - Nichole LeClair Terrill
Art Director - Cliff White
Staff Writer - Bonnie Chasteen
Staff Writer - Jim Low
Photographer - Noppadol Paothong
Photographer - David Stonner
Designer - Stephanie Thurber
Artist - Dave Besenger
Artist - Mark Raithel
Circulation - Laura Scheuler