applied at 5.4, 10.8, and 21.7 kg/ha. The ineffec-
of 10 days and an efficacy of at least 80% reduction
tiveness of DP920324B to reduce mallard feeding
of feeding activity. Sentinel studies should not be
in treated pools was attributed to the pliable struc-
used to compare relative risk of MA vs control
pens directly because even small sampling rates
ture of the beads. Mallards were unable to break
over a prolonged observation period place captive
the beads to release the methyl anthranilate. Ex-
ducks at risk of WP poisoning. MA works by mov-
periments with SE920326 at application rates of 5.4
ing waterfowl away from areas of treatment, not
and 10.8 kg/ha showed slight treatment effects.
by suppressing feeding 100%. Thus, field studies
SE920326 applied at 21.7 kg/ha to bottom sedi-
on free-ranging ducks are needed to further evalu-
ment was effective in reducing the time mallards
ate the efficacy of MA as a short-term remediation
spent in treated pools (p < 0.05). SE920326 applied
strategy.
to contaminated waterfowl feeding areas at 21.7
kg/ha could reduce feeding and mortality and
Collins, C.M., and D.J. Calkins (1995) Winter test
warrants further testing in the field.
of artillery firing into Eagle River Flats, Fort Rich-
ardson, Alaska. USA Cold Regions Research and
Henry, K.S., and S.T. Hunnewell (1995) Silt fence
Engineering Laboratory, Special Report 952.
testing for Eagle River Flats dredging. USA Cold
Winter tests of artillery firing were conducted
Regions Research and Engineering Laboratory,
in the Eagle River Flats impact range to determine
Special Report 9527.
the physical effects of exploding high-explosive
An estimated 1000 to 2000 waterfowl deaths
(HE) projectiles on the ice-covered terrain. Eagle
have been noted annually since 1980 in Eagle
River Flats (ERF), Alaska, an artillery impact area
River Flats is an estuary at the mouth of the Eagle
used by the Army. Waterfowl die because of the
River used as the artillery impact range for Ft.
ingestion of unburned white phosphorus (WP)
Richardson. The Army suspended use of the
particles deposited by incendiary rounds. Reme-
impact range following the discovery that white
phosphorus (WP) deposited in the salt marsh was
diation of the site is currently being planned, and
responsible for large numbers of waterfowl deaths
one of the techniques being considered is the use
each summer. The purpose of these tests was to
of a remote-control dredge to excavate WP-
assess if seasonal firing of HE projectiles from 60-
contaminated sediment. Dredged material will be
and 81-mm mortars and 105-mm howitzers into
placed into a settling pond and allowed to settle
Eagle River Flats could be resumed without signif-
until a clear layer of water forms on the top of the
icantly disturbing the sediments contaminated
sediments. The water will then be released over a
with WP. The results of the test firings indicated
weir, across a concrete pad, through a geotextile
that a minimum of 25 cm of ice over frozen sedi-
silt fence to a drain into the ERF. This report
ment or a minimum of 30 cm of floating ice over
describes tests that were conducted to evaluate
shallow water was required to prevent distur-
how well candidate geotextiles for the silt fence
bance of the WP-contaminated sediment by
retained small particles (less than 0.1 mm in diam-
exploding 105-mm howitzer projectiles. Only 10
eter) that were suspended in water being released
cm of ice was required to prevent disturbance by
back into the ERF. The soil used in the tests was
exploding 60- and 81-mm mortar projectiles.
collected from ponds to be dredged. The testing
program consisted of two parts. Part I tests were
standard engineering tests for silt fences, and were
Cummings, J.L., L. Clark, S.A. Bird, J.E. Davis Jr.,
H.W . Krupa, and P.A. Pochop (1993) Effects of
used to select a product for further testing. Part II
methyl anthranilate bead formulations on mallard
tests simulated field conditions, and were con-
feeding behavior in an aqueous environment. In
ducted to determine whether the candidate geo-
U.S. Army Eagle River Flats: Protecting waterfowl
textile selected was likely to perform well. Under
from ingesting white phosphorus. USDA Denver
simulated field conditions, the tests that used geo-
Wildlife Research Center Technical Report 931, p.
textiles achieved system filtering efficiencies of
833.
99%, and the geotextile filter reduced the final
We applied two methyl anthranilate (MA) bead
total suspended solids contained in the water by a
formulation to bottom sediment in a simulated
factor of 10. Negligible amounts of soil passed the
pond setting to evaluate bird repellency to captive
no. 200 sieve from water that flowed through the
mallards (Anas platyrhynchos). Formulations and
geotextile. However, it is also noted that allowing
application rates were: DP920324B (5% MA)
the sediment to settle before decanting the water
applied at 5.4 kg/ha and SE920326 (5% MA)
resulted in system filtering efficiencies in excess of
82
to contents
Previous Page
