TRIBAL PROGRAM NEWS
Natural Resources Water Projects News
by Stan van de Wetering
1999 Eel Project
During the summer of 1999, we
examined the distribution of baby eels
throughout the Alsea River Basin. The U.S.
Fish and Wildlife Service funded the project,
which originally was intended for the Siletz
area, but poor land access forced us to
move to the Alsea Basin. In doing so, we
didn’t gain information on specific tributaries
of interest within the Siletz Basin, but we did
increase our understanding of how eels are
distributed throughout our mid-coast region
(a portion of the original reservation).
We divided the Alsea Basin into areas
based on characteristics such as distance
from the ocean, substrate geology (gravels
made from sandstone versus hardrock),
stream gradient, and land cover (timber, ag,
and rural). Next, we hopped in the stream
with our electroshocker and began
collecting eels.
An electroshocker is a small device
that sends an electrical current through the
water and substrate that make up a stream,
irritating the baby eels and causing them to
swim up to the surface. We counted how
many eels we found per square meter. We
looked for both Pacific and brook lamprey.
Brook lamprey are those small (6-inch long)
light brown eels you may have seen
spawning in small streams with
sandy bottoms.
We found eels in all of our Alsea Basin
sample streams except those that reached
gradients greater than 2 percent and or were
smaller than about 2 to 3 feet wide. An
example of where eels would not occur
would be the upper reaches of Little Rock
Creek about one mile above the end of the
pavement on Logsden Road.
We also did not find any eels in good
habitat above the North and South Fork falls
or any culverts with more than a few inches
of drop. The absence of eels above the North
and South Fork falls was surprising based
on how well eels can climb vertical falls. This
may simply reflect their current low numbers.
Our greatest densities were in larger
waters. This suggests that those areas
where we have surveyed and found many
baby eels, such as the mainstem Siletz from
Twin Bridges to Cedar Creek, should be
considered areas of ecological interest to
the tribe.
that mile of stream. Lastly, you measure,
using stream flows, how much water is
passing through that mile of stream. The
model can then estimate what temperature
any given stream will be, based on air
temperature, amount of sun or shade, and
amount of water in the creek. You also can
estimate how cooling one creek can affect
another or vice versa.
Estuary Project
The old office building at the tribal
hatchery stands no more.
We received a third tiny grant ($6,000)
to continue eel work in 2001. We plan to use
these funds to develop a new statistical
method to estimate the number of baby eels
in a complete sub-basin such as
Rock Creek.
Well Head and Stream
Flow Project
John has entered most of the well log
data (location, depth of water, type of
substrate) and has been collecting surface
flow information more recently. He has spent
a lot of time learning how to use our fancy
new computer software, which will allow us
to describe aquifers and stream flows in a
three-dimensional format. This project ends
in February 2001, so we should have some
results for you by early winter.
E PA 106 Project
During summer 2000, we have
focused on collecting data for our stream
modeling process. This has involved using
small computers that measure water and air
temperature every 60 minutes at 47 sites
within the Siletz Basin. We also will use
satellite photos and stream flow
measurements for this model.
The model works this way. First, you
measure how much light is reaching each
mile of stream for all streams. Next, you
measure what the water temperature is for
We chose to focus this year’s funding
on mapping all available habitat types so we
can do a more extensive job of sampling the
bay in the future. We will use our new GIS
software to map depths, salinities,
temperatures, marsh plants, and critters that
live in the bay’s mud and sand. We are
utilizing infrared photography to map plant
communities and it’s been quite interesting.
Chlorophyll, which makes plants look
green, shows up as different shades of red
when using infrared photography. This
technique will allow us to define small
changes in plant communities in a quick
manner. We recently received new funding
for this project from the National Marine
Fisheries Service and hope it will increase
our annual work effort in the bay, allowing
us to better monitor our fish stocks.
Hatchery Update
Tommy arranged for the installation of
the first section of the new fence in July.
A contract also was set up to demolish the
old office building next to the road. We have
three outstanding contracts to dig an
additional rearing pond, to refurbish the adult
trap, and to build a pole barn where the old
office used to stand. We hope to complete
this work by the end of October.
We sampled the coho presmolts in
early July and they looked very healthy.
Their size and condition were as good or
better than those of wild fish with which I’ve
had experience. Although we are unsure of
their survival rate (how many are still alive),
we are hopeful at this point in
our experiment.
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