Researchers poised for Elwha ecosystem studies

The Elwha watershed promises to be an outdoor laboratory for the revival of an ecosystem after two dams are removed from the Elwha River.

Elwha Dam construction begins. (Click on image for webcam page.)
Olympic National Park photo

Dam removal began Thursday at Glines Canyon Dam, as I traveled to Port Angeles for a conference of more than 350 scientists and other interested persons. This group came together to learn about baseline studies conducted to date and to hear about anticipated changes in the ecosystem. Check out my story in Sunday’s Kitsap Sun.

Meanwhile, a controversy over a fish hatchery operated by the Lower Elwha Klallam Tribe threatens to erupt into a lawsuit. Several environmental groups have issued a 60-day notice to sue under the Endangered Species Act, saying raising steelhead from another area — Chambers Creek — could imperil the recovery of threatened chinook salmon and bull trout in the Elwha. See reporter Lynda Mapes’ story in the Seattle Times.

Will Stelle of the National Marine Fisheries Service, which oversees federal protections for salmon, said discussions about the hatchery are ongoing, but federal treaties assure the tribes a right to fish, and those rights cannot be ignored. A five-year moratorium on fishing has been imposed, but tribal officials say they may need hatchery-reared fish when fishing resumes.

About a year ago, I briefly described the restoration plan for each species — including salmon and steelhead — in a package of stories for the Kitsap Sun. See “Elwha Project Expected to Blast Open Nature’s Door to Bountiful Fish Runs.”

As for last week’s Elwha River Science Symposium, it was a remarkable group of researchers who discussed all aspects of ecosystem restoration, from physical processes like water and sediment, to all kinds of plants and animals. To get a taste of the presentation, read through the conference abstracts (PDF 584 kb).

I mentioned a few of the presentations in Sunday’s Kitsap Sun, and I could talk about them for hours. There was one presentation about birds that surprised me, and I wanted to share some of the conclusions with you.

John McLaughlin of Huxley College at Western Washington University explored the question of how birds might help restore vegetation in the reservoirs and flood plains associated with the Elwha and Glines Canyon dams.

Of 39 major native plants in the watershed, 23 have their seeds dispersed by birds. That’s 59 percent of the plants of interest. If managers could get the birds working for them, they might not need to plant as much vegetation by hand.

That 59 percent is higher than most temperate regions of the world, where normally birds disperse seeds from 25 to 40 percent of the plants, McLaughlin said. But it’s a lower percentage than for most tropical regions, where birds may disperse up to 90 percent of all the plants in the area.

By watching birds fly from vegetated areas to more barren areas and collecting samples of their scat, McLaughlin found that robins disperse more seeds than all other birds combined. In fact, the total was close to 100 percent for robins. While there are plenty of other bird species in the ecosystem, most typically do not fly from one habitat type to another, McLaughlin told the gathering.

He also found that most of the seeds deposited by robins ended up in and near logjams and piles of woody debris.

“Birds are agents of restoration,” he told the group, “but for them to work with us, you have to give them what they need, and that’s large woody debris.”

If one wants to use birds to replant the forest, the first step is to consider which plants you want to disperse, he said. Then downed trees and limbs could be pulled together into a pile, or one could simply leave existing piles in strategic locations. The woody piles must be located far enough from the desirable plants that the birds can make a difference in dispersing seeds. But if the piles are too far away, the birds may not cooperate with the plan.

As for the concern about birds dispersing invasive plants as well as desirable ones, many of the undesirables were removed from the area around the dams in preparation for dam removal. The concern about invasives is reduced further by understanding that only five of the 20 invasive plants are dispersed by birds.

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