Conserving Habitat for Ducks & Fish

DU’s groundbreaking fisheries research proves restored wetlands benefit both waterfowl and salmon

Ducks Unlimited biologists recently found themselves in a quandary. In the midst of expanding work to restore wetlands in floodplains of major rivers in the Northwest, they ran up against government regulators who called DU's plans harmful to salmon.

"Regulators were making it almost impossible for us to get permits to restore wetlands, because of perceived conflicts with fish," said Chuck Lobdell, DU's conservation manager for the lower Columbia River. "And we thought restoring wetlands was good for the whole environment."

Lobdell, who has a master's degree in fisheries biology, said fishery biologists in the region paid scant attention to floodplain wetlands, instead viewing river systems as little more than conduits between spawning grounds and the ocean. But when various stocks of salmon were added to lists of endangered, threatened, and sensitive species in the late 1990s, regulatory officials became concerned with any activity in watersheds that supported salmon, and in particular, they worried that DU's newly restored wetlands could attract, trap, and strand juvenile salmon.

This puzzled DU's biologists. After all, DU was restoring wetlands that had previously existed. Salmon had flourished when these wetlands were intact. But today's restoration is limited to what is possible given the constraints of a highly altered environment. So regulators saw DU's restored wetlands as a new and possibly threatening environment into which today's salmon could wander.

When settlers arrived in the Northwest, they found rich and abundant wetlands along the lower reaches of the region's big rivers. Set against towering mountains, these floodplains provided flat land, along with access to rivers for transportation. It was here the settlers drained and leveed off the land to build cities and farms.

Since then, dams, channel deepening, and water diversion have further degraded these once ecologically diverse areas, resulting in the loss of more than 85 percent of the region's floodplain wetlands. Gone are the great complexes of off-channel wetlands, oxbow ponds, meandering shoals, and expanses of aquatic vegetation that sustained waterfowl in the Northwest.

Into this altered environment generations of fishery biologists were born, leaving little wonder that scant attention was paid to the role of floodplain wetlands in the life of salmon. After all, how would anyone know the value to salmon of wetlands that had been destroyed so long ago?

When DU began restoring these great floodplain wetlands, it was hailed as an environmental landmark. But then fisheries officials began to worry that wetlands would harbor predators that eat juvenile salmon. They believed salmon might enter wetlands and be stressed or die because of high water temperatures, or simply become stranded there and die. However, there were no offsetting requirements to improve habitat for waterfowl. Ducks Unlimited biologists were asked if wetlands were at best an attractive nuisance to salmon or at worst a death trap.

Pressed with unanswerable questions, Lobdell set out to build a research base necessary to satisfy regulators' concerns. As there had been so little research conducted on salmon use in floodplain wetlands, DU had to develop new techniques to determine the effect of different wetland restoration designs on salmon and to find out if a certain balance in design would maximize value for both fish and ducks.

With this goal in sight, DU began what at the time may have seemed rather odd for an organization focused on ducks. DU began an intensive program of fishery research coupled to wetlands restoration project design. Supporting partners in this work were M.J. Murdock Charitable Trust, Oregon Watershed Enhancement Board, FishAmerica Foundation, Pacific Coast Joint Venture, The David and Lucille Packard Foundation, The Wertheimer Family Trust, National Fish and Wildlife Foundation, U.S. Environmental Protection Agency Wetland Program, U.S. Forest Service, and Oregon Sea Grant.

This research has provided a wealth of useful information. "Restored floodplain wetlands were proven to provide significant benefits to both ducks and salmon," said Cyndi Baker, DU fishery research biologist. A doctoral student at Oregon State University, Baker is using data from researching fish use of restored floodplains for her doctoral dissertation.

"We are among the first to conduct fishery studies in floodplain wetlands in the West," Baker said. "Restoration by DU has increased the acreage of wetlands at a rapid pace, making them so important to the overall ecology of the region that it's critical to study them."

Restoration is intended to reestablish the ecological function of rivers and their floodplains. One tool to accomplish this is to reconnect floodplains to rivers by building channels and "fish-friendly" water-control structures. Through these channels and structures salmon may enter and exit newly restored wetlands.

Baker conducted her work at 15 restored floodplain wetlands throughout Oregon and Washington. She collected fish entering, exiting, and residing in restored wetlands. She then developed predictive models to relate relative abundance of fish species to characteristics of the wetland environment, such as temperature or presence of predators. Movement of fish into and out of wetlands was compared with differences in characteristics between the river and wetlands. Finally, she looked at growth and condition of salmon in wetlands and adjacent rivers.

Baker faced numerous challenges. Many of the salmon she worked with are listed as endangered or threatened, so any that she captured had to be returned alive. Wetlands are difficult places in which to work even under the best of circumstances. Baker conducted her work in the harsh conditions of winter, often complicated by flooding and even ice cover, which forced her to go under the ice to take samples.

Through research, DU pioneered ways to restore wetlands to benefit waterfowl without running afoul of requirements to protect endangered fish. In the process, DU made a revolutionary discovery in river floodplains, demonstrating their value to both salmon and waterfowl!

As an added benefit, where restored wetlands support salmon recovery, DU now taps into new funding sources for wetlands restoration. In the lower Columbia and Willamette rivers, about half of all DU projects are fish related and partially funded by state and federal fish habitat restoration grants. In Puget Sound, about 40 percent of all work is funded with grants and contracts specific to restoration of fishery habitat, and about 80 percent of the acreage accomplishments have fish benefits. For example, a $9 million project on the Nisqually National Wildlife Refuge will restore 700 acres at the mouth of the Nisqually River, providing significant benefits to salmon and waterfowl. Throughout the Northwest, DU restored more than 9,000 acres of estuary and floodplain wetlands over the last two years, all of which will provide significant benefits to fish.

The research continues with each project DU builds, as engineers and biologists improve design and management of projects to benefit both ducks and fish. This is now standard procedure in the Northwest, where endangered salmon share an aquatic world with ducks.

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