Wetlands shrink slows during last five years, need to conserve continues

WASHINGTON — America’s wetlands declined slightly from 2004-2009, underscoring the need for continued conservation and restoration efforts, according to a report issued today by the Department of the Interior’s U.S. Fish and Wildlife Service. The findings are consistent with the Service’s Status and Trends Wetlands reports from previous decades that reflect a continuous but diminishing decline in wetlands habitat over time.

The report, which represents the most up-to-date, comprehensive assessment of wetland habitats in the United States, documents substantial losses in forested wetlands and coastal wetlands that serve as storm buffers, absorb pollution that would otherwise find its way into the nation’s drinking water, and provide vital habitat for fish, wildlife and plants.

“Wetlands are at a tipping point,” said Secretary of the Interior Ken Salazar. “While we have made great strides in conserving and restoring wetlands since the 1950s when we were losing an area equal to half the size of Rhode Island each year, we remain on a downward trend that is alarming. This report, and the threats to places like the Mississippi River Delta, should serve as a call to action to renew our focus on conservation and restoration efforts hand in hand with states, tribes and other partners.”

“This report offers us a road map for stemming and reversing the decline,” said Fish and Wildlife Service Director Dan Ashe. “It documents a number of successes in wetlands conservation, protection and reestablishment, and will be used to help channel our resources to protect wetlands where they are most threatened and reduce further wetland losses.”

The net wetland loss was estimated to be 62,300 acres between 2004 and 2009, bringing the nation’s total wetlands acreage to just over 110 million acres in the continental United States, excluding Alaska and Hawaii.

The rate of gains from reestablishment of wetlands increased by 17 percent from the previous study period (1998 to 2004), but the wetland loss rate increased 140 percent during the same time period. As a consequence, national wetland losses have outpaced gains.

The net loss includes a combination of gains in certain types of wetlands and losses in other types, especially forested wetlands.

“In a five year period, we lost over 630,000 acres of forested wetlands, mostly in the Southeast – an area equal to half a million football fields each year,” Director Ashe said. “We should all be concerned about the substantial loss of this diminishing resource, which helps ensure good water quality for local communities and provides vital habitat for a diversity of important wildlife species.”

The southeast United States, primarily freshwater wetlands of the Atlantic and Gulf coastal plain, and the Lower Mississippi River experienced the greatest losses. Losses were also observed in the Great Lakes states, the prairie pothole region, and in rapidly developing metropolitan areas nationwide. The reasons for wetland losses are complex and reflect a wide variety of factors, including changes in land use and economic conditions, the impacts of the 2005 hurricane season on the Gulf Coast and climate change impacts.

This report does not draw conclusions regarding the quality or condition of the nation’s wetlands. Rather, it provides data regarding trends in wetland extent and type, and it provides information to facilitate ongoing collaborative efforts to assess wetland condition. Further examination of wetland condition on a national level has been initiated by the Environmental Protection Agency in conjunction with the U.S. Fish and Wildlife Service and other federal, state and Tribal partners.

Wetlands provide a multitude of ecological, economic and social benefits. They provide habitat for fish, wildlife, and a variety of plants. Wetlands are nurseries for many saltwater and freshwater fishes and shellfish of commercial and recreational importance. Wetlands are also important landscape features because they hold and slowly release flood water and snow melt, recharge groundwater, act as filters to cleanse water of impurities, recycle nutrients, and provide recreational opportunities for millions of people.

The report, Status and Trends of Wetlands in the Conterminous United States 2004-2009, is the most recent of the five reports to Congress reporting on the status and trends of wetlands across much of the United States since the mid-1950s.

Source: USFWS

Catastrophic amphibian declines have multiple causes

CORVALLIS, Ore. – Amphibian declines around the world have forced many species to the brink of extinction, are much more complex than realized and have multiple causes that are still not fully understood, researchers conclude in a new report.

The search for a single causative factor is often missing the larger picture, they said, and approaches to address the crisis may fail if they don’t consider the totality of causes – or could even make things worse.

No one issue can explain all of the population declines that are occurring at an unprecedented rate, and much faster in amphibians than most other animals, the scientists conclude in a study just published in the Annals of the New York Academy of Sciences.

Caring for those useful seasonal wetlands

Seasonal, sometimes isolated wetlands like this one in a pasture in the Miami River watershed of Tillamook County perform important functions that keep watersheds healthy, wildlife abundant, and water clean. Photo by Robert Emanuel, OSU.

Wetlands comprise a significant feature of the North Coast’s landscape. These include estuaries and freshwater ecosystems that are generally subject to inundation and wet soils all year. In some cases, a wetland can be seasonal too, though the definitions can become fuzzy. Tillamook and Clatsop counties are literally filled with indications of wetlands this time of year. You’ll see waterfowl, amphibians, and even some fish that manage to make it into them.  Insects, native mammals and a variety of terrestrial species depend upon seasonally flooded wetlands.

But more importantly from a watershed perspective, wetlands provide us an invaluable service. They are great at taking some of the “excess” runoff from intense storms and storing it temporarily, allowing it to either infiltrate into subsurface flow or aquifers, or by storing it as it evaporates. Furthermore, these temporary wetlands absorb nutrients and sediment before they can pollute our rivers or bays.

Unfortunately, wetlands have been replaced or filled in much of the United States.  In fact, most of the rivers that drain into our major estuaries were flooded forests or grasslands in which most vegetation was governed by seasonal floods.  The soils in much of the low elevation portions of Tillamook Bay basin, for example, would be classified as “hydric” or influenced by saturation were they not drained during the late 19th and early 20th centuries by the hard work of pioneering farm families. In many places, you can still find the plants that prefer these soils. They are what wetland ecologists use as indicators of seasonal or permanent wetlands. An example is the small-fruited bullrush (Scirpus microcarpus) below.

Small fruited bullrush (Scirpus microcarpus) is a good indicator plant of wetland soils and conditions. Photo by Robert Emanuel, OSU.

After removal of riparian forests, the construction of dike and drainage systems have  permanently changed the soils and vegetation of former wetlands into the economically important working landscapes we recognize today.  But this doesn’t mean that the wetlands are gone. In fact, looking across pastures this time year, you can still see some seasonal wetlands where drainage is poor and water pools temporarily.  And practically speaking, most farmers would prefer to keep their livestock out of these wet soils.  In the meantime, wildlife use such as breeding amphibians or waterfowl will temporarily increase as the wet and warming spring continues.

What can you do to keep your temporary wetlands functioning as flood water storage and sinks for nutrients or sediment?

1. If your seasonal wetlands appear in active pastures, try to keep livestock use light once soils are dry enough to allow animals on to them.

2. If you are grazing in or near these seasonal wetlands, rotate your livestock on and off them depending on soil saturation. If soils are too wet–such as early in the spring–then keep animals out of them. Wet soils compact easily, leading to less infiltration during the wet season and more flooding for lands adjacent to the wetland.

3. Consider fencing some areas for exclusive wildlife and recreational use, particularly if the soils stay wet for most or all of the year.

4. Establishing or allowing woody vegetation such as willows to grow on the edges or within these more saturated areas will increase flood water retention and capture more nutrient or sediment-laden runoff.

5. Watch for weeds: several nasty invasive species prefer to live in wetlands, so watch for purple loosestrife, yellow flag iris, and common reed. Once found, eradicate them immediately by  an appropriate, aquatic registered herbicide or mechanical removal.  Keep up the eradication program until you don’t see the plants return. Remember that invasives can move quickly on muddy equipment, livestock, pets or clothing.  You can find out more about some of these invaders at the Oregon Invasive Species Hotline or visiting your local OSU Extension Service office.

6. Don’t try to drain your seasonal wetlands. These are important parts of the landscape and should be enjoyed as useful for healthy watersheds, abundant groundwater, and wildlife.