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 Research
Issues:
Air Pollution Impacts on Aquatic Biota
Inventory of Air Quality Related Values Affected by Atmospheric Deposition
The Influence of Marine-Derived Nutrients on Water Quality and
Biological Productivity
Genetics and Demographics of Amphibians
Hybridization and Competition between Native and Nonnative Fish Populations
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Air Pollution Impacts on Aquatic Biota:
Background:
Atmospherically deposited pollutants may pose a substantial risk to aquatic resources in Mount Rainier, North Cascades, and Olympic National Parks. Acidic deposition, excessive nitrogen loading from the atmosphere, and pesticides in rain and snow are prime examples of pollutants that can have negative impacts on aquatic ecosystems in national parks. Air pollution from nearby urban areas affects the air quality in these parks and may also be affecting park resources. Preliminary scientific evidence indicates that significant quantities of a wide variety of pollutants are carried across the Pacific Ocean from Asia to North America, sometimes in as few as four days. These pollutants may be affecting surface water quality and associated biota. Although precipitation chemistry is monitored at three National Atmospheric Deposition Program/National Trends Network stations in Western Washington, these sites are at low and mid elevations; little information is available about precipitation chemistry at high-elevation sites in the parks in Washington because of the difficulty of access. However, data from a bulk precipitation collector located at approximately 5000-ft. elevation on the south side of Mount Rainier National Park has shown elevated levels of sulfates and nitrates.
MORA, NOCA, and OLYM receive abundant precipitation, mostly in the form of snow, which accumulates during the winter in a deep seasonal snowpack. When the snowpack melts in the spring, large amounts of mildly acidic snowmelt are released quickly into the terrestrial and aquatic ecosystems. The terrestrial ecosystem provides little buffering capacity because soils are poorly developed and bedrock consists mostly of unreactive volcanic and granitic bedrock that weathers relatively slowly. Thus, snowmelt moves rapidly into lakes and streams with little modification. During the initial phase of snowmelt, high concentrations of solutes often are released, causing an "acid pulse" from the snowpack (Johannessen and Henriksen, 1978) Mid-winter melting or rain-on-snow precipitation events, which are common in the northern Cascade Mountains, can cause multiple acid pulse events that can adversely affect aquatic biota.
Glaciers provide abundant particulate matter which can act as a carrier of some pollutants. As reservoirs of snow from distant winters, it is also possible that glaciers contain atmospheric pollutants from decades ago. Unexpected pulses of pollutants may occur when glacial ice containing pollutants reach the glacier margin and melt. Stored pollutants could potentially significantly affect aquatic resources in the parks considering the volume of snow and ice in each park. North Cascades National Park Service Complex (NOCA) encompasses more than 300 glaciers and numerous perennial snowfields. Mount Rainier National Park (MORA) contains numerous perennial snowfields and 25 major glaciers covering 35 square miles and with an ice volume of 991 million square feet and 156 billion cubic feet. In Olympic National Park there are over 260 glaciers, 11 major watersheds, and over 400 lakes and wetlands.
Recent research in the Canadian Rockies and elsewhere indicates that biota in glacier-fed subalpine lakes contain high concentrations of organochlorines (OC) such as DDT and PCB. These reports are somewhat surprising, since these lakes are in high elevation, pristine environments that are far distant from direct sources of pollution. However, as in MORA, NOCA, and OLYM, the lakes studied at Banff National Park receive meltwater from glaciers and abundant winter snowfall. The scientists studying the Banff lakes predicted that source water for lakes fed by glaciers will have relatively high levels of OC pesticides for at least another century.
The presence of atmospherically deposited pollutants in snow, rain, and glaciers is a topic of increasing concern as scientists seek to explain declines in amphibian populations in remote areas of the United States. There is presently no information available to park managers on current or past levels of OC pollution of glaciers, lakes or aquatic biota. This knowledge gap is critical as we develop management programs to address impacts from fish-stocking, global change, and human recreation.
Park Focus:
Mount Rainier National Park
North Cascades National Park
Olympic National Park
Research Needs:
How do accumulations of OCs and other persistent organic pollutants and heavy metals in fish and/or amphibians vary with respect to watershed area, elevation, and snow and ice drainage?
What are the levels of pesticide concentrations in seasonal snowpacks along elevational gradients during the period of maximum accumulation?
How do the relative levels of pollutants differ between glacial-fed and non glacial-fed lakes?
Do pollutant levels vary along an east-west gradient that corresponds to a precipitation gradient?
Is there a relationship between contaminant burden in fish and/or amphibian tissues and those of organisms at lower trophic levels and lake bottom sediment?
Can these contaminant concentrations found in the top predators at each lake be related to other physiographic/biologic factors of the recipient watershed?
What atmospherically deposited pollutants are deposited in glaciers and snowpacks within the three parks? Do concentrations of these pollutants vary geographically?
Available Resources:
Chemistry of many lakes in North Cascades NP has been surveyed recently in support of a high lakes management plan.
Limnologic, paleolimnologic data is available for most lakes within MORA. Fish and amphibian surveys have also been conducted at many lakes and ponds.
A diatom calibration set is available for the Cascade Mountain Ecoregion. (Eilers, J.M., P.R. Sweets, D.F. Charles, K.B. Vache. 1998. E&S Environmental Chemistry, Inc. Corvallis, Oregon)
References Cited:
Johannessen, M., and Henriksen, A., 1978, Chemistry of snow meltwater: changes in concentration during melting: Water Resources Research, v. 14, no. 4, p. 615-619.
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Inventory of Air Quality Related Values Affected by Atmospheric Deposition:
Background:
Both local and regional sources of air pollution are now affecting air quality related values (AQRV) in MORA and NOCA. Studies indicate that regional sources of air pollution from the Vancouver, BC area are affecting visibility in NOCA, while visibility in MORA is being affected by urban sources in the Puget Sound area and by the Centralia Power Plant, now the largest source of SOx in the western United States. These visibility-reducing particles include nitrates and sulfates, the same pollutants that can cause changes in surface water chemistry and aquatic biota populations when deposited in rain, snow, cloudwater or as dry deposition.
Park resource managers need to identify the most sensitive aquatic systems in these two Cascade Mountain parks and then develop a long-term monitoring strategy to chart the health of these high-elevation, low acid-neutralizing capacity (ANC) waters and their biological populations. Previous water quality surveys at high elevations, non-glacier fed lakes and streams, that there are now waters in both MORA and NOCA with as little as 10 ueq/l of ANC. We need to develop simple, quality-assured methods to quantify the acid-deposition stress to these sensitive watersheds, where most of the deposition of solutes occurs as snow. This seasonal snowpack then melts during a relatively short period in the spring; this rapid flush of melt water can result in episodic acidification of headwater lakes and streams, primarily located on the western side of these two parks.
To be able to synthesize information on dose (deposition chemistry) and response (water chemistry), we need to apply existing watershed acidification models using site-specific data on watershed soils and hydrology. To attempt to trace changes in deposition chemistry to regional or local sources of air pollution, we can analyze sulfur isotopes in rain, snow, and lake and stream waters. Finally, to protect park resources from air pollution, we will need sufficient data on dose-response to develop critical load estimates, or the amount of sulfur and nitrogen being deposited to the most sensitive lakes and streams to avoid adverse affects on water quality and biota.
Park Focus:
Mount Rainier National Park
North Cascades National Park
Olympic National Park
Research Needs:
What is the loading of hydrogen, sulfur, and nitrogen compounds in wet deposition to high-elevation sites in the Cascades?
What is the relative contribution of snow, rain-on-snow events, and summer rains to total wet deposition?
How is deposition loading distributed, at maximum snowpack accumulation, between wet depostion, rime ice, and dry deposition?
What are the best methods to utilize in the long-term monitoring of snow, rain-on-snow events, and summer rains?
How do these values change along a north to south transect in each park?
How do water chemistry and hydrology change in lakes, stream and ponds during the snowmelt period? What is the contribution of snowmelt dilution and acidic inputs to the loss of ANC during this period?
Zooplankton and benthic invertebrates are known to respond to episodic acidification. What is the distribution of zooplankton, benthic invertebrate species, and amphibian species in lakes chosen as sample sites?
The Model of Acidification of Groundwaters in Catchments (MAGIC) needs to be tested and refined for determination of surface response to depostion of sulfur and nitrogen in the Cascades. This will require collection of additional field data.
Analyze deposition and surface waters for sulfur isotopes: Examples of the use of naturally occurring
S isotopes in rain, snow and surface water to determine if the source of sulfate is natural or anthropogenic, are available. This method has been successfully used in the Rocky Mountains to distinguish between a local, point source of S emissions (coal-fired power plant) and regional emissions of S.
This method should be applied to the target waters in MORA and NOCA to better understand the
sources of S in deposition.
Available Resources:
Lake databases are available for each park and should be useful in the selection of sampling sites based on surface water sensitivity and sources of water runoff.
Eilers, J.M., P.R. Sweets, D.F. Charles, K.B. Vache. A Diatom Calibration Set for the Cascade Mountain Ecoregion. E&S Environmental Chemistry, Inc. Corvallis, OR. Prepared for PACIFICORP, Centralia, Washington. 1998, 78pp.
Eilers, J., C. Rose, and T. Sullivan. Status of Air Quality and Effects of Atmospheric Pollutants on Ecosystems in the Pacific Northwest Region of the National Park Service, Technical Report NPS/NRAQD/NRTR-94/160, 1994, 259 pp.
Glesne, R. et al. Long-Term Ecological Monitoring Prototype Proposal for Lakes and Rivers: North Cascades National Park Service Complex, Prepared for NPS Inventory and Monitoring Program, September 1993.
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The Influence of Marine-Derived Nutrients on Water Quality and
Biological Productivity:
Background:
Mount Rainier, North Cascades, and Olympic National Parks encompass over one million acres of land with extensive riverine systems. Although historically the majority of these rivers contained anadromous runs of salmon, dam construction has limited the ability of salmon to enter a number of national park rivers. Today, rivers flowing from these parks range from those with relatively healthy runs of salmon (i.e., west-side of Olympic National Park) to rivers that have no anadromous runs due to dams (i.e., Mount Rainier). Many rivers in these three parks no longer receive the input of nutrients from salmon carcasses, and therefore have likely become more oligotrophic. Small changes in the abundance of nutrients can have a dramatic effect on whole aquatic ecosystems. The elimination and reduction of salmon runs in many of the streams within each of the parks due to dams and other anthropogenic factors may have a serious long-term effect on aquatic and terrestrial resources within all three national parks. Detailed understanding of the role of marine-derived nutrients in these systems are essential for the development of effective long-term protection guidelines for these areas.
Upon their return from the sea, anadromous salmonids provide marine-derived nutrients to freshwater ecosystems through their excretion, gametes, and carcasses (Donaldson 1967; Brickell and Goering 1972; Mathisen et al. 1988; Schuldt and Hershey 1995; Bilby et al. 1996). These nutrients are important to the productivity of the lakes and streams in which they spawn (Larkin and Slaney 1997), to their progeny (Kline et al. 1990; Bilby et al. 1996), and to many terrestrial animals (Cederholm et al. 1989; Piorkowski 1995; Willson and Halupka 1995; Hildebrand et al. 1996). Using museum specimens of grizzly bears, Hildebrand et al. (1996) determined that salmon once contributed 33-90% of the metabolized carbon and nitrogen in grizzly bears in the Columbia River drainage before hydroelectric dams and irrigation projects impeded or blocked salmon migrations. Important park vertebrates such as Douglas squirrels (Glaucomys sabrinus), otters (Lutra canadensis), minks (Mustela vison) and black bears (Ursus americanus) are among 22 species of birds and mammals that have been observed feeding on salmon carcasses (Cederholm et al. 1989). The occurrence (or lack) of anadromous fish runs also affects wildlife biology (i.e., distributions, behavior, survival) and the conservation of biodiversity (Willson and Halupka 1995).
Since low levels of primary and secondary productivity are typical of many coastal streams in the Pacific Northwest, Larkin and Slaney (1997) concluded that even modest inputs of nutrients and carbon from relatively few anadromous fish may be important in stimulating primary production and maintaining trophic productivity. In fact, as few as 24 chinook salmon carcasses have been found to increase N and P concentrations in a small stream (Schuldt and Hershey 1995). Alternatively, it follows that small reductions in the numbers of anadromous fish could significantly degrade ecosystem processes and productivity, which can contribute to a negative feedback loop (due to lessened biological productivity/oligotrophication) and increasingly reduced production levels (Larkin and Slaney 1997: 22). Associated decreases in parr and smolt sizes can reduce overwinter and marine survival, resulting in decreased adult returns and further reducing stream productivity (Ward and Slaney 1988; Bilby et al. 1996).
While these issues are complex and not easily remedied, fisheries management actions are, or should be, flexible and modified with increased scientific understanding. For example, harvest management in Washington State is most often based on the theory of maximum sustained yield (MSY), which includes the concept of an optimum escapement level. Larkin (1977, 1978) estimated that optimum escapement may be only 30-50% of the unfished population level. In contrast, salmon carcasses may contribute 30% of the nitrogen and 34% of the carbon assimilated by coho salmon juveniles in western Washington streams (Bilby et al. 1996), so far more spawners may be needed to escape to ensure fish population health and ecosystem productivity than the levels MSY would suggest (Bilby et al. 1997).
More scientific analysis is needed to determine escapement levels that sustain both productive fisheries and ecosystems. Results of research in this area will have immediate application to park management in upcoming projects such as the removal of dams on the Elwha River in Olympic National Park,the re-licensing of the Baker River hydroelectric project adjacent to North Cascades National Park, and restoration of anadromous fish runs in Mount Rainier National Park.
Park Focus:
Mount Rainier National Park
North Cascades National Park
Olympic National Park
Research Needs:
What is the relative contribution of marine-derived nutrients to stream communities in various streams throughout the three parks?
How do current surface water nutrient conditions and proportions of various trophic levels in the food web, that are from marine-derived nutrients, vary across habitat conditions in the three parks?
How has the elimination or reduction of salmon within Mount Rainier, North Cascades, and Olympic National Parks limited nutrient availability in aquatic and terrestrial habitats?
How would the re-introduction of salmon to these systems change productivity and water quality in these systems?
Determine whether ecosystem-based salmon escapement goals will result in higher salmonid production than the standard method of MSY (maximum sustained yield).
Available Resource:
References of historic occurrence of fish park streams in MORA.
References Cited:
Bilby, R.E.; B.R. Fransen; and P.A. Bisson. 1994. Role of coho salmon carcasses in maintaining stream productivity: evidence from nitrogen and carbon stable isotopes. Pages 160-167 in M.L. Keefe, editor. Salmon ecosystem restoration: myth and reality. Proceedings of the 1994 Northeast Pacific chinook and coho salmon workshop. Oregon Department of Fish and Wildlife, Portland. 1996. Incorporation of nitrogen and carbon from spawning coho salmon into the trophic system of small streams: evidence from stable isotopes. Canadian Journal of Fisheries and Aquatic Sciences 53:164-173.
Brickell, D.C., and J.J. Goering. 1972. Chemical effects of salmon decomposition on aquatic ecosystems. Pages 125-138 in R.S. Murphy and D. Nyquist, editors. International symposium on water pollution control in cold climates, University of Alaska. U.S. Government Printing Office, Washington, D.C.
Cederholm, C.J., D.B. Houston, D.L. Cole, and W.J. Scarlett. 1989. Fate of coho salmon (Oncorhynchus kisutch) carcasses in spawning streams. Canadian Journal of Fisheries and Aquatic Sciences 46:1347-1355.
Donaldson, J.R. 1967. The phosphorus budget of Iliamna Lake, Alaska, as related to the cyclic abundance of sockeye salmon. Ph.D. dissertation. University of Washington, Seattle.
Hildebrand, G.V., and five coauthors. 1996. Use of stable isotopes to determine diets of living and extinct bears. Canadian Journal of Zoology 74:2080-2088.
Kline, T.C., Jr., and five coauthors. 1990. Recycling of elements transported upstream by runs of Pacific salmon: I. 15N and 13C evidence in Sashin Creek, southern Alaska. Canadian Journal of Fisheries and Aquatic Sciences 47:136-144.
Larkin, G.A., and P.A. Slaney. 1997. Implications of trends in marine-derived nutrient influx to south coastal British Columbia salmonid production. Fisheries 22:16-24.
Larkin, P.A. 1977. Pacific salmon. Pages 156-186 in J.A. Gulland, editor. Fish population dynamics. John Wiley & Sons, New York.
1978. Fisheries management - an essay for ecologists. Annual Review of Ecology and Systematics 9:57-73.
Mathisen, O.A., and five coauthors. 1988. Recycling of marine elements transported into freshwater systems by anadromous salmon. Verh. Internat. Verein. Limnol. 23:2249-2258.
Piorkowski, R.J. 1995. Ecological effects of spawning salmon on several southcentral Alaskan streams. Ph.D. dissertation. University of Alaska-Fairbanks.
Richey, J.E., M.A. Perkins, and C.R. Goldman. 1975. Effects of kokanee salmon (Oncorhynchus nerka) decomposition on the ecology of a subalpine stream. Journal of the Fisheries Research Board of Canada 32:817-820.
Schuldt, J.A., and A.E. Hershey. 1995. Effect of salmon carcass decomposition on Lake Superior tributary streams. Journal of the North American Benthological Society 14:259-268.
Ward, B.R, and P.A. Slaney. 1988. Life history and smolt-to-adult survival of Keogh River steelhead trout and the relationship to smolt size. Canadian Journal of Fisheries and Aquatic Sciences 45:1110-1122.
Willson, M.F., and K.C. Halupka. 1995. Anadromous fish as keystone species in vertebrate communities. Conservation Biology 9:489-497.
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Genetics and Demographics of Amphibians:
Background:
Amphibians have recently been a focus of concern due to the serious population declines documented worldwide (Barinaga, 1990; Blaustein and Wake, 1990). Amphibians are sensitive indicators of environmental conditions and constitute a major portion of animal biomass in many habitats. In forested areas, they exceed the combined weight of all vertebrates. Amphibians play a key food chain role because of their large numbers and also because they occupy a high position in the food chain. Recent literature and studies in North Cascades National Park (Liss et al., 1995), Crater Lake National Park, and Mount Rainier National Park have clearly demonstrated that the multiple age classes in reproducing populations of nonnative salmonids have a great impact on native lake communities which evolved under fishless conditions. Fish predation affects the food webs in the lakes, altering nutrient cycling, the structures of zooplankton and benthic macroinvertebrate communities, and the distributions, behaviors and abundances of the prey taxa. Fish predation has also been shown to have a major impact on amphibian abundance, behavior and distribution, especially salamander populations, even when a fish population occurs in low density. In some cases prey taxa have been eliminated from lakes and ponds. The loss of amphibians would have a profound affect on forest ecosystems.
Salamanders have been identified as the top native vertebrate predator in highmountain lakes throughout the western United States (Taylor 1983; Liss et al. 1995), especially many small lakes naturally barren of fish. During this century most highmountain lakes in the west that were large enough to support fish populations were stocked with trout (Bahls 1992). These introduced fish potentially contributed to the decline of amphibian populations in aquatic systems (Blaustein and Wake 1995). Recent studies in the Cascade Mountains at Mount Rainier National Park (Unpublished park data) and North Cascades National Park Service Complex (Liss et al. 1995) in Washington State, plus additional studies in the Sierra Nevada Mountains in California (Bradford et al. 1993), have shown that the presence of trout in highmountain lakes clearly coincides with significant reductions of salamander and annuran abundances. These results are consistent with negative changes in growth, survival, and behavior of larvae of two species of pondbreeding Ambystoma inhabiting the southeastern U.S.
Recent studies at Mount Rainier National Park and North Cascades National Park clearly demonstrate that salamander populations increase in abundance if introduced fish are eradicated or greatly reduced in abundance. Apparently remnant populations of salamanders still exist in highmountain lakes containing high densities of fish, and these salamander populations can increase in abundance when predation pressures are eased. Ponds provide important habitat for amphibians, especially salamander populations, and are a likely source of refugia for recolonizing adjacent lakes after fish removal. Land managers concerned about natural communities in highmountain lakes need better data on the genetics and demographics of amphibian populations for the development of long-term protection of these species and the potential restoration of high-elevation lakes and ponds.
Park Focus:
Mount Rainier National Park
North Cascades National Park
Olympic National Park
Research Needs:
What are the dispersal patterns of amphibians from breeding areas?
What are the environmental attributes that affect dispersal of amphibians?
What are the patterns of genetic diversity within and among populations of the species of interest?
How do these patterns vary between populations in fishless lakes and lakes with fish?
What are these patterns for adult populations and larval populations?
What is the relationship between within-population genetic diversity of amphibians and larval amphibian population size in fishless lakes?
How can these data be applied to amphibian recovery plans if fish are removed from some lakes?
Species of interest for park research: northwestern salamander, Ambystoma gracile (MORA); Cascades frog, Rana cascadae (MORA, NOCA); Columbia spotted frog, Rana luteiventris (NOCA); and western toad, Bufo boreas (MORA, NOCA).
Research Cited:
Bahls, P. 1992. The status of fish populations and management of high mountain lakes in western United States. Northwest Science 66: 183-193.
Baringa, M. 1990. Where have all the froggies gone? Science 247:1033-1034.
Blaustein, A. R. and D. B.Wake. 1990. Declining amphibian populations: a global phenomenon? Trends in Ecology and Evolution 5:203-204.
Bradford, D. F., Tabatai, F., and D. M. Graber. 1993. Isolation of remaining popoulations of the native frog Rana mucosa, by introduced fishes in Sequoia and Kings Canyon National Parks, California. Conservation Biology 7(4): 882-888.
Liss, W. J., Larson, G.L., Deimling, R., Gresswell, R. Hoffman, M. Kiss, G., Lomnicky, C. D., McIntire, R. and T. Tyler. 1995. Ecological effects of stocked trout in naturally fishless high mountain lakes: North Cascades National Park Service Complex, WA, USA. NPS/PNROSU/NRTR-95-03. National Park Service, Pacific Northwest Region, Seattle.
Taylor, J. 1983. Orientation anjd flight behavior of a neotonic salamander (Ambystoma gracile) in Oregon. American Naturalist 109(1):40-49.
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Hybridization and Competition between Native and Nonnative Fish Populations:
Background:
Introductions of non-native fish species have heavily impacted native stream-resident, salmonid populations. Introductions have altered wild populations through competition and hybridization. Of particular concern is the hybridization between introduced rainbow trout and native cutthroat populations; native cutthroat and other introduced subspecies of cutthroat trout; native rainbow stocks and introduced rainbow stocks; hatchery produced salmon and steelhead; and between brook trout and native char species (bull trout and Dolly Varden). Hybridization can be difficult to detect morphologically and the most common genetic method (allozyme analysis) is lethal and dependent upon allele frequency differences bewteen native and nonnative species. Thus, there is a need for a reliable species specific, non-invasive hybridization method. Non-lethal techniques also need to be applied in sorting out distribution of native Dolly Varden and bull trout populations. Identification of hybrids and pure stocks will allow managers to determine the risk of stocking programs on specific drainages, or asses the status of existing native stocks in areas that are adopting wild salmonid policies, such as national parks.
Park Focus:
Mount Rainier National Park
North Cascades National Park
Olympic National Park
Research Needs:
Where is the degree of hybridization in native stream-resident salmonids and where is it occurring?
Development of non-lethal methods and genetic markers to detect levels of hybridization in native stream-resident salmonids.
Application of molecular biological techniques to determine distribution of native char (Salvelinus confluentus) and Dolly Varden (Salvelinus malma).
Application of molecular biological techniques to determine distribution and genetic purity of park stream resident salmonid fish populations.
Available Resources:
North Cascades has fish stocking records and distribution data on fish within the complex.
Mount Rainier has extensive information on fish stocking in streams and some data on current general fish presence in streams (c. 1993 to present).
Olympic has access to stocking records for the park and fairly detailed fish distribution records.
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