o Service Assessment Studies Principal Investigators: W. H. Rickard and D. G. Watson Other Investigator: R. E. Fitzner Technical Assistance: H. A. Sweany Service Assessment studies, supported through the Richland Operations Office, are related to long-term ecological monitoring of important anl'mals on the Hanford Site. This report concerns the Canada goose, the great blue heron and chinook salmon spawning. Biological Monitoring: Canada Goose Nesting Goose nests are relatively easy to locate since they are almost always restricted to Biological monitoring has received in- islands that are relatively small and only creasing amounts of attention and funding sparsely covered with plants. since the advent of the National Environmen- tal Policy Act of 1969. Some of the most There was a general lack of information advertised biological monitoring studies are concerning the biological fate and effects of those associated with the siting and opera- radioactivity released into the Columbia tion of commercial nuclear power stations. River from operating plutonium production Such studies are designed to obtain biologi- reactors. Thus, a program to monitor goose cal data for 1 or 2 yr prior to power sta- nests was initiated in 1953 to determine if tion operations to provide baseline informa- the hatchability of goose eggs was deleteri- tion concerning the kinds, and an estimate ously affected by the radioactive effluent of abundance, of organisms most likely to be water being released to the river. These affected by either construction activities studies showed that the release of radio- or by extended station operations. nucl ides to the Columbia River by Hanford 's production reactors had no deleterious impact A1 though biological monitoring is gener- on the hatchabi 1i ty of goose eggs. ally accepted as a worthwhile practice, there is some concern that the experimental designs The production reactors began to be phased of sample-taking, which relate operational out in 1964 and by 1971 eight of nine reac- factors to changes in wild animal popula- tors were no 1onger operating. Nevertheless, tions, are mostly inadequate. Another con- the total number of nests found on the islands cern is that monitoring will need to be con- diminished from more than 250 nests in the ducted over long periods of time, i .e., 30-40 1950's to about 120 in the 1970's (Figure 8.1). yr, necessitating a long-term funding Although this is a dramatic decline, it is commi tment . not nearly so severe as compared to the vir- tual loss of the entire island nesting popu- One of the distinct advantages of survey- lation associated with the nearby Snake ing nesting goose populations on the Hanford River. The decline of the Snake River popu- Site is that the entire nesting population lation is attributed to the inundation of can be censused rather than sampled, thereby nesting islands by the construction of four eliminating some of the statistical uncer- hydroelectric dams that have created slack tainties associated with sample-taking . water from the confluence of the Columbia All Islands -- -- SUCCESSFUL TOTAL YEARS Locke Island SUCCESSFUL TOTAL YEARS FIGURE 8.1. Total number of goose nests on 20 islands in the Hanford Reach of the Columbia River from 1953-1977: the number of nests that successfully hatched (upper diagram) and the same data for Locke Island (lower diagram), an island that has been occupied by coyotes since 1970. River to the Idaho border. In contrast, the coyote occupied the island prior to the Columbia River Reach of the Hanford Site has nesting season. Since 1970, coyote control not been dammed. has been abandoned altogether and its destruc- tive influence on goose nesting is clearly The steady decline in goose nests can be shown in the following years (Figure 8.1). attributed to human interferences, since the lower reaches of the Columbia River have been The data are now very useful because of subjected to recreational uses over the past the time span involved and their continuity. decade. Coyote predation is a1 so an impor- They now serve as a baseline from which to tant factor. The most dramatic example of judge the impact of future envi ronmental coyote predation occurred on Island 6 (Locke perturbations associated with the development Island), which is not subject to human recre- of the Columbia River as an energy source and ation. At one time this island supported as a water transportation route. A research more than 100 nests. In autumn 1966, two opportunity is also present to determine if coyotes swam to Island 6 and remained there the nesting goose population can be restored until they were shot in February 1968. The to Locke Island by selectively controlling an number of goose nests increased in 1969 but important goose predator, the coyote. in 1970 nesting was a complete failure as a Radionuclide Content of Rejecta from Heron Nests: A Colony Comparison TABLE 8.7. Average Ash Weight and Radionuclide Content (pCi/g ash) of Cheesecloth Blankets With One of the environmental concerns associ- and Without Accumulations of Heron Rejecta at ated with the proliferation of nuclear reac- Hanford, WA and Lake Chatcolet, ID. tors and selection of new sites for the chemical processing of irradiated fuel is the Location Ash wt. 13'Cs 60C0 40K 144Ce potential for escapement of long-lived radio- ----- nuclides into the adjacent environment. Once Blankets with Rejecta radionuclides enter the biological environ- ment they may participate in food chains. Hanford 290 4.7 0.55 29 7.1 Food chains leading to man are usually well Chatcolet 106 1.2 0.28 16 15 defined and are amenable to radiological surveillance procedures. However, the food Control Blankets chains of higher trophic level animals, other than man, have seldom been investigated in Hanford 66 3.2 1.2 37 20 terms of radiological surveillance. Chatcolet 6 26 8.7 123 224 Conventional radiological surveillance techniques involve the collection of domestic meat, fruits and vegetables, milk, eggs, the shooting or trapping of wild animals from Hanford Site. Lake Chatcolet is in a cli- time to time and then subjecting organs or matically moist and heavily forested region tissues to radiochemical analysis. This pro- with 1ittle blowing dust. When radionucl ide cedure is useful for sampling wild, gallina- content is expressed as pcilindividual con- ceous birds and waterfowl (birds with high trol blanket then Hanford blankets accumu- reproductive potential) but is not entirely lated more radioactivity than Chatcolet acceptable for raptorial birds and certain control blankets. However, when expressed as kinds of wading birds with low reproductive pCi/g ash weight, the less dusty Chatcolet potential. For example, shooting for radio- control blankets had higher concentrations of logical surveillance purposes could seriously 137C~,60C~, '+OK and 14'+Ce. deplete small populations of ospreys and great blue herons, fish-eating birds with low Cheesecloth blankets spread beneath heron reproductive potential. nests at Hanford accumulated more nest re- jecta than blankets of Chatcolet i.e., 289 g The great blue heron, Ardea herodias, is at Hanford as compared to only 106 g at a large, fish-eating bird that characteris- Chatcolet. Cheesecloth blankets with accu- tically nests in the same grove of trees year mulated heron rejecta at Hanford also had after year. Nesting begins in early spring greater concentrations of 37Cs, 60C~, '+OK with nest refurbishing and egg-laying. Two and 14'+Ce than Chatcolet blankets. When to five eggs are laid in each nest. When expressed as pCi/g ash, Hanford blankets the young birds hatch, parent birds bring with rejecta had greater concentrations of food, mostly fish, to the nest to feed the 137Cs, 60C~and '+OK, but lesser amounts of growing young. Although different parents 14'+Ce. may select different foraging areas located at various distances from the colony, food The natural ly-occurring radionucl ide '+OK items are transported to the colony to feed derived from parent soil and rock was the the growing young. Food scraps and fecal most abundant radionuclide measured in heron material collectively called "rejecta" are rejecta. Cerium-144, a short-lived fission cast over the sides of the nests and can be product, probably had its origin in worldwide collected and chemically analyzed for year- fallout. It is possible that the slightly to-year and site-to-si te comparisons. elevated levels of 137Cs and 60C~in rejecta originated from past operations at the Han- Cheesecloth blankets spread on the ground ford Site but the levels are too low to be beneath heron nests and beneath trees without of biological significance. heron nests at Chatcolet Lake, Idaho, and at the Hanford Site, Washington, showed that Radionucl ide (gamma emitters) content of worldwide fallout contributed small amounts heron rejecta was very low but measurable at of radionuclides to cheesecloth through Hanford, Washington, and at Lake Chatcolet, direct aerial deposition (Table 8.7). Idaho, indicating that 30 yr of processing Control blankets on the Hanford Site accumu- nuclear fuels at the Hanford Site have con- lated more ash weight than blankets at Lake tri buted 1ittle, if any, radioactivity to Chatcolet, largely because of wind-blown dust present day heron foods. Surveillance of from the sparsely vegetated ground at the heron rejecta appears to be a sensitive, nondestructive way to survey radionuclide levels in the foods of a top trophic level conditions ranged from poor to good. The animal during a critical phase of its life spawning area at Midway (river mile 393) cycle. The cooperation of Dr. Don Johnson, continued to be the most difficult to survey llniversity of Idaho in locating the Lake due to high river elevations resulting from Chatcolet heron colony and peroiission of daytime release of water at Priest Rapids Heyburn State Park to conduct the study are Dam.
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