Dames & Moore, 1999 - USDA Forest Service

estimated from the available liver and muscle data. The whole body copper, mercury, selenium and zinc
concentrations that would be consumed by osprey feeding on trout are shown in Table 7.2.3-6. These
values agree well with those reported by Harper Owes (1989) for kokanee. chinook salmon. and rainbow
trout collected.in Lake Chelan. In that study, whole body copper ranged from 0.66 to 2.4 mg copperkg. and
zinc ranged from 5 to 19 mg/kg. Roch et al. (1985) have also shown that liver and muscle cadmium.
copper, lead and zinc concentrations do not differ significantly between rainbow and cutthroat trout exposed
to mine tailings contaminated water. Therefore, the values for rainbow trout are also applicable to cutthroat
trout. While the copper and zinc concentration means increased between the upstream area and the
downstream of tailings pile 3, iron, selenium and mercury decreased over the same area.
Ecology (Patmont et al., 1989) also collected fish tissue data on arsenic, cadmium, lead, mercury, and
selenium concentrations in kokanee, chinook salmon, and rainbow trout from different areas of Lake
Chelan. Arsenic, cadmium, lead, selenium and mercury were below method detection limits. There was no
relationship between copper, zinc, or selenium concentrations in these fish and the proximity of the
collection area to Railroad Creek.
Using USEPA (1993) algorithms, the concentrations of metals ingested by ospreys through drinking were
conservatively estimated h m the UCL of the surface water copper, iron, mercury, and zinc (total)
concentrations collected in the Fall of 1997. Selenium was never detected. Table 7.2.3-8 shows the
estimated doses for a 1.55 kg adult male osprey consuming 0.255 kg of fish per day, and drinking 0.05 Ukg
body weightlday.
- Mink
Mink are carnivores which feed, in order of importance, on mammals, fish and amphibians, birds, reptiles
and invenebrates. Population density depends upon available cover and food, but typically ranges from
0.01 to 0.1 mink per ha. Mink home range depends largely upon food abundance but ranges from 7.8 to
20.4 ha. in heavily vegetated and sparsely vegetated habitats, respectively (Mitchell 1961). Home ranges
are usually aligned with waterways and, in Idaho, mink were never observed more than 200 m from water
(Melquist et al., 198 1).
In some locations, the mink derives a major portion of its diet from fish consumption (Erlinge, 1969; EPA,
1993), but mink are not successful in capturing salmonid or other fast swimming fishes in some areas
(Erlinge, 1969). However, in Michigan, Alexander (1977) reponed that trout comprised between 52 and 56
percent of the diet during different seasons. Nevertheless, for the purposes of conservatism, it was assumed
that trout comprised 100 percent of the diet along Railroad Creek (Table 7.2.3-6).
EPA (1993) algorithms were also used to estimate the doses for mammals. The water ingestion rate (W) in
mammals was estimated as:
~:\wpd.u~~\repom~lo1~2\n\74.d0f 7-57
17693-00S419Uuly 21.1999:S:16 PMPRAFT FINAL RI REPORT
W (Ud) = 0.099 x (kg Body 7-19