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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