Assessing the Health of the Lake Hazen Ecosystem, Ellesmere Island, Northwest Territories.
Douglas Clark, Parks Canada, P.O. Box 353, Pangnirtung, NT, X0A-0R0, e-mail: doug_clark@pch.gc.ca
Abstract
Lake Hazen on Ellesmere Island is the largest lake in the world entirely within the Arctic Circle, and is the centre of a High Arctic oasis of ameliorated climate and relatively high plant and animal abundance. Research and monitoring in this area in a variety of disciplines started in 1958, and some efforts continue. Paleolimnological investigation suggests that a large-scale climatic change has taken place, possibly since the 18th Century. A review of previous research reveals no evidence to suggest that significant changes have occurred in the Lake Hazen Ecosystem within the last 4 decades. However, few temporal comparisons of physical and biological variables were possible, despite the breadth of investigations over those years. Water quality in Lake Hazen did not appear to change significantly between 1963 and 1990. Recent samples (1996) from the only outflow river show reduced cation concentrations, possibly due to increased flow rates at the time of sampling. Low levels of contaminants from long-range transport appear to be present in water, lake sediment and Arctic char (Salvelinus alpinus) tissue. Trophic systems are simple and species-poor, and no changes in species presence or absence have been documented within the last 40 years. It is suggested that demographics of species, may provide more sensitive indicators of terrestrial ecosystemic change in the High Arctic than changes in species diversity. A strategy for integrated research and monitoring of the Lake Hazen Ecosystem is presented.
Key Words
Lake Hazen, Ellesmere Island, Northwest Territories, National Park, ecosystem, ecosystem health, ecological integrity, contaminant, global change, paleolimnology, biodiversity, monitoring.
Introduction
Lake Hazen (81°N, 71°W) on Ellesmere Island, NWT, is the largest lake in the world entirely within the Arctic Circle, measuring 537.5 km2 (Figure 1). Surrounded to the north by the Garfield mountains (1600m ASL) , and to the south by the Hazen Plateau (300m- 1300m ASL), it is protected from the main flow of air from the polar basin onto the Queen Elizabeth Islands, and so experiences an ameliorated climate (Jackson 1964). Such areas in the High Arctic generally support richer and more abundant vegetation and fauna than the surrounding landscape, and are termed "oases" (Bliss 1977, Svoboda & Freedman 1994). The Lake Hazen Basin is no exception, with relatively high vegetation cover and locally abundant wildlife, compared to either the barren Hazen Plateau or to the surrounding mountain ranges (Savile and Oliver 1964, France 1992).
The Hazen Basin is formed of carbonate-rich sandstones and mudstones of the Hazen Fold Belt, and has been heavily glaciated (Trettin 1994). Though the basin generally lies at less than 300m ASL, the surface of Lake Hazen may have been up to 150m higher than at present, and likely had more than one outflow (Bednarski 1994). Currently, Lake Hazen is fed by multiple glacial inflows and has only one outflow, the Ruggles River. Bathymetry of Lake Hazen is incomplete, but it has a depth of at least 253m (Deane 1958).
The geographic, climatic and biotic uniqueness of the Hazen basin suggest that it may be considered as a discrete functional ecosystem. A preliminary delineation of such a Lake Hazen Ecosystem (LHE) would bound the drainage basin, and is shown in Figure 2. The LHE as outlined measures 4900km2 : two to three orders of magnitude larger than the intensively studied polar oases at Truelove Lowland (42km2) and Alexandra Fiord (8km2) (Freedman, Svoboda & Henry 1994).
The LHE was inhabited from approximately 4000 BP to the 18th Century (Dick, Adams and Sutherland 1994). The first quallunaq (non-Inuit) to visit Lake Hazen was Major Adolphus Greely in 1882, as part of the International Polar Year (Hattersley-Smith, 1974). Research in the LHE began in 1957 when the Defence Research Board mounted "Operation Hazen": an expedition which overwintered at Hazen Camp, on the north shore of Lake Hazen (Figure 2). This multidisciplinary party collected a variety of geological and biological data; and fieldwork continued, though less intensively, until 1968 (Hattersley-Smith 1974). The Geological Survey of Canada's Polar Continental Shelf Project (PCSP), has supported research parties in the Lake Hazen area, and throughout the High Arctic, since 1959. In 1988 Ellesmere Island National Park Reserve (EINPR) was established to protect the northern tip of Ellesmere Island, including the LHE.
Much of the existing ecological data for northern Ellesmere Island was compiled in the National Park's Resource Description and Analysis (Parks Canada 1994). While comprehensive, this document did not attempt any analysis or synthesis of information. Critical examination indicates that the only data set from which temporal comparisons for any biota can be made is the collection of Arctic char (Salvelinus alpinus L.) made between 1958 and 1996. Most of the biological studies have concentrated on the aquatic portion of the LHE hence more data is available than for terrestrial subjects. Some comparisons of physical variables are possible, but overall there is a surprisingly low yield of temporal data, given the volume of work which has taken place in the LHE over the last 40 years. However, it should be remembered that fieldwork in the High Arctic is both expensive and difficult: criticism of such previous work must be tempered with consideration of this.
The original intent of this paper was to examine existing published and unpublished research results to detect temporal trends in variables which may indicate changes in the health or integrity of the LHE. "Health" and "integrity" are relative terms (Woodley 1993), used interchangeably here to indicate whether a system is significantly affected by anthropogenic influences, and whether it retains the capacity for adaptation and evolution. In the course of this investigation it became apparent that the components of the ecosystem are reasonably well documented, but many of its basic processes and trophic relationships are only hypothesised or extrapolated (Johnson, 1997). Without greater knowledge of the specifics of the LHE, any measurement of system parameters will lack sufficient context for reliable interpretation. Therefore, I make recommendations for monitoring and focused research in order to more fully understand the nature and health of the LHE.
Aquatic Ecology
Most nutrient input into Lake Hazen is from glacial runoff, and emergent or benthic vegetation is confined to ponds. Possibly because of the lake's depth and the generally low prevailing winds, Lake Hazen often retains some portion of ice cover, which can vary from none to almost 100%, throughout the year (McLaren 1964). Windspeed is generally low year-round at Hazen Camp (Jackson 1959, Tarnocai 1996), though the basin is so large that different areas may have different wind regimes (R. Wissink, pers. comm.). This may influence ice breakup in different parts of the lake at different times. The 15 km long Ruggles River is the only river draining Lake Hazen, and the lake's outflow into the river is generally ice free year-round (Deane 1958).
Oliver & Corbett (1966) suggested that the Ruggles River is indicative of conditions in Lake Hazen as a whole. Gregor and Dahl (1990) agreed, and further remarked at the similarities between that 1963 data and their results from 1989 and 1990. However, they cautioned that these relationships may not hold through the summer season, when inflowing meltwater may disrupt the homogeneous water column. Table 1 shows water chemistry parameters from these studies, as well as collections made by Parks Canada, Environment Canada, Atmospheric Environment Board and the Department of Fisheries and Oceans in 1995 and 1996. Analytical methods differ among the collections, though laboratory precision has probably increased over time. Lake Hazen is slightly alkaline, highly oligotrophic and apparently unstratified during much of the year. Dissolved organic carbon (DOC) screens out UV-B radiation: the low levels present in Lake Hazen (Table 1) indicate that the lake's biota is likely to be vulnerable to any increase in UV-B from stratospheric ozone depletion.
Little change is evident between 1963 and 1990, and cation concentrations in 1996 are generally lower than in previous years. Calcium is the ion in highest concentration, consistent with the findings of Hamilton et al. (1994). The atypical results from 1996 suggest that the Ruggles may not necessarily be indicative of lake conditions throughout the year. The glacial and non-glacial inflows have markedly different characteristics (Parks Canada/ Environment Canada, unpublished data), and their relative input volume, and timing, is unknown. Additionally, Lake Hazen is exceptionally large for Arctic lakes, and its sheer size may buffer some processes and obscure the effects of individual inflows. Simultaneous sampling in the major inflows, the outflow and the lake at all hydrological stages would be required to establish what is happening. Continued monitoring of the chemistry of the Ruggles River is clearly required. An annual total of 25mm of precipitation was estimated in 1958 (Jackson 1959), though this estimate may be in error (Thompson 1989). Nevertheless, precipitation in the LHE is very low, so glacial melt is likely to be a major portion of the inflow into Lake Hazen. Therefore, the monitoring of glacial mass balance in the United States, British Empire and Garfield Ranges is critical to understanding the hydrology of Lake Hazen.
Sediment-cores from Lake Hazen exhibit a pronounced diatom species shift, similar to a shift observed elsewhere in the High Arctic in the mid-19th Century, though the species involved differ among sites (Douglas, Smol & Blake 1994). Lake Hazen appears to have been dominated by Fragilaria spp., then rapidly developed a more diverse community including Cyclotella spp., Achnanthes spp., Amphora spp., Cymbella spp. and Navicula spp. (M. Douglas, pers. comm.) . This suggests that the LHE was subjected to the same rapid, large-scale climatic change inferred for the High Arctic (Douglas, Smol & Blake 1994). However, because the samples may have been taken from slumped sediments, this shift could not be precisely dated. Further sampling and examination of cores is warranted.
McLaren (1964) investigated zooplankton production in Lake Hazen, and concluded that persistence of summer ice cover had a significant limiting effect on the dominant species, Cyclops scutifer Sars. This copepod has a biennial life cycle in Lake Hazen, and by examining relative proportions of different larval instars in samples collected in 1958, he predicted production to 1957 through 1961. However, production was not measured in those years, and ice cover was only roughly estimated by different observers. Replication of his studies would be valuable.
Arctic char were collected in 1958, 1981, 1990, 1992, 1995 and 1996. Johnson's (1983) comparison between samples from 1958 and 1981, as well as preliminary examination of 1995 and 1996 data, indicates no change in age or size structure of this population. Two morphotypes of Arctic char are present in Lake Hazen: a large, cannibalistic form, and a small, presumably benthic- feeding form (Reist et al. 1995). Taken together, the results of both radiotelemetry studies in 1995-6 (Babaluk et al. in prep.) and, more conclusively, strontium uptake by char (Halden et al. 1996) suggest that neither form is anadromous. However, this is in contradiction to Inuit traditional knowledge, which holds that the char in Lake Hazen do go to sea (Ellesmere Island National Park Reserve Advisory Board, March 5, 1997). A comprehensive demographic analysis of the char population of Lake Hazen is in progress (J. Reist, pers. comm.). Fecundity information is still required. Nothing is known specifically about the detritus cycle in Lake Hazen, and little about the benthic chironomids, which form the bulk of the food of immature and small-form char.
Anthropogenic Contaminants
Low levels of Cesium 137 were detected in Saxifraga oppositifolia tissue collected from Ellesmere Island (France et al. 1993), most of it apparently deposited prior to the 1986 Chernobyl nuclear accident. Organic contaminants are present in the LHE (Tables 2, 3, and 4). The concentrations of these compounds are lower than at lower latitudes, consistent with the hypothesis of northward deposition by cold condensation (Muir et al. 1995). Biological effects of these concentrations are likely negligible so far, but no search has been undertaken in Lake Hazen for specific effects. For example, morphological abnormalities in benthic invertebrates are a sensitive, readily detectable indicator of pollution stress (Schindler 1987): sampling for this would be relatively easy for Park staff, though analysis would require external expertise.
It is possible that DDT was introduced into the LHE during military operations, however no mention of insecticide use was made by Hattersley-Smith and Lotz (1961). Analyses of polycyclic aromatic hydrocarbons (PAHs) in Lake Hazen is complicated by the presence of coal seams on the lakeshore, which have been eroding into the lake, introducing PAHs of natural origin. Heavy metals are also present (Table 5) and with the exception of mercury (Hg) are generally at slightly lower concentrations than in fish tissues at lower latitudes (Lockhart et al. 1992, Muir and Lockhart 1993).
Terrestrial Ecology
An International Tundra Experiment (ITEX) site was established in 1993 by Parks Canada, with the assistance of Josef Svoboda (University of Toronto). Park staff monitored basic phenology of Dryas integrifolia and Saxifraga tricuspidata, without the temperature modification experiment described in Molau and Mølgaard (1996). However, monitoring of this site was discontinued in 1996 due to operational constraints. This most northerly site in the global ITEX network deserves greater continuity of effort, or adoption of annual ITEX measures, which require only brief annual visits and would still provide consistent, comparable information.
Paleo-Inuit Independence I people spread from Alaska along the "Muskox Way", through the LHE, to Greenland as early as 4000 BP (Dick, Adams and Sutherland 1994). Thule people inhabited the LHE until the 18th Century (ibid.). These people, the intervening Dorset culture, and to a lesser extent the Independence II culture, made significant use of Muskoxen (Ovibos moschatus) and other terrestrial fauna (ibid.). Greely's (1881-3), and later, Peary's expeditions (1900-1906), based on the east coast of Ellesmere Island, provisioned themselves by hunting Peary caribou (Rangifer tarandus pearyii) and muskoxen as far west as Lake Hazen. The impact of their harvest may have been substantial: Peary's party took 75 caribou in 1905-6 (Barr 1991), which would represent exceptional hunting effort if caribou then existed at present densities. One could infer from this that caribou were more abundant prior to exploitation. However, they likely were never numerous if a harvest of 75 animals caused the population to decline. Over 1000 muskoxen were killed on Ellesmere Island by explorers between 1880 and 1917 (ibid.). Kelsall (1984) documented a harvest by Greely (1881-83) of 111 muskoxen, and by Peary (1898-1902) of approximately 140 muskoxen in the area between Lake Hazen and the east coast. The muskoxen population appears to have recovered, though caribou remain uncommon in the LHE.
Radiotelemetry data from 1994-1997 from one satellite-collared Peary caribou bull showed that it returned each winter to the Gilman River area on the north shore of Lake Hazen (Parks Canada, unpublished data). Vegetation is distributed patchily throughout the LHE, and the fidelity of wildlife to productive areas is not surprising. This should be borne in mind should any future developments be contemplated in the LHE. Further, this caribou, and a satellite-collared male Arctic wolf (Canis lupus) have both ranged in and out of Ellesmere Island National Park Reserve between 1994 and 1997 (Parks Canada, unpublished data). This reinforces the need to consider that different ecosystem elements may have different spatial boundaries, which may not coincide with political boundaries (Johnson and Agee 1988). No traditional harvest of wildlife currently takes place in the LHE, so present human impact on wildlife is limited, as would be expected in a National Park. Some habituation of wildlife does occur through interaction with visitors, and food seeking from camps (B. Troke, pers. comm.) and, in the past, at CFS Alert (R. Wissink, pers. comm.). It should be noted that the staff of CFS Alert have recently made significant progress sanitizing their landfill in order to reduce attractions to wildlife.
Gould (1988) compared her observations of mammals and birds in the Hazen Camp area in 1981-2 with those of previous parties (Nettleship and Maher 1973, Savile and Oliver 1964, Tener 1959). She concluded that no species immigrated to, or became extinct in the area during that period. Breeding bird surveys, currently being planned for summer 1997 by Parks Canada, would provide useful quantitative data for comparison with previous observations.
Ravens (Corvus corax) are associated with human presence throughout the Arctic. Though present in the community of Grise Fiord, 500km to the south (D. Clark, unpublished observations, March 1997), individuals have only been observed sporadically at Hazen Camp: in 1981 (Gould 1988) and 1995 (R. Wissink, pers. comm.). This species is not resident in the LHE, and future residency might be an indication of increasing human use in the area. Similarly, no exotic plants have been documented in the LHE. While their establishment is unlikely, any new occurrences should be carefully documented.
Presently, human use of the LHE is limited. Roughly 400 people per year visit Lake Hazen: military personnel from Canadian Forces Stations Eureka & Alert, National Park staff, commercial guides and approximately 50 adventure tourists. Development and most activity has been limited to two sites: Hazen Camp and the Kenn Borek Air camp on the south shore near the Ruggles River. Since the latter camp burned in 1992, activity there has ceased.
Studies by Tarnocai and Gould (1996) show that there is little impact from present levels of hiking traffic in the LHE: a significant proportion of trails are apparently made by muskoxen. Vehicle traffic, however, has left readily visible tracks at the two camps. Kevan et al. (1995) documented significant localized impacts from vehicle traffic at Hazen Camp. They observed that heavily tracked areas exhibited increased thaw depth, reduced vegetation cover, reduced soil nutrients and reduced productivity of soil arthropod fauna. Their results make a strong case against the use of vehicles on unfrozen ground in the LHE.
Discussion
Detecting Change in Arctic Ecosystems
The Arctic is inhabited by generalist species with broad environmental tolerances, and by very few endemic species (Remmert 1980). Though local extinction and re-immigration probably occur, these species exhibit stable distributions over long time spans and large areas. For example, LaFarge-England (1989) demonstrated from a peat deposit at the east end of the Hazen Basin, that plant assemblages have remained constant at that site since 6400 BP. Given this, it is unlikely that presence/absence data or measures of species diversity will provide useful indications of possible changes.
No change in diversity in birds, mammals, vascular plants, mosses or soil arthropods has been documented in the LHE, suggesting that even relatively diverse taxa may not readily change species composition in the High Arctic, even under stress. This principle may not hold true for aquatic systems, since diatom diversity has changed in both High Arctic lakes and ponds (Douglas & Smol 1994). Schindler (1987) noted that disruption of ecosystem functions may be buffered by other system processes until a system collapses. Species shifts, or indications such as disappearance of sensitive species are only sometimes apparent. In practical terms, diversity-based indices of ecosystem health, such as Karr's Index of Biological Integrity (see Karr 1993 for review) are thus of little value in the Arctic. For example, even with modifications (Steedman 1988), this index cannot be applied to Lake Hazen: there are simply too few taxa to calculate a meaningful index.
Demographic information would likely be more revealing for most taxa. Population-level responses to stresses are detectable with present techniques, but would require significantly more resources and effort than are involved in the present collection of basic presence/absence data. Given the demonstrably low predictive ability of such data, investing in population studies and monitoring is worth the effort, and determination of presence/absence probably is not, with the single notable exception of diatoms.
Recommendations for Monitoring Ecosystem Health in the LHE
McCanny and Henry (1995) describe an ecosystem monitoring program which is currently being implemented in National Parks throughout the NWT. While comprehensive and operational, this plan does not provide a way to integrate and interpret data to provide insight at the ecosystem level. One possible approach to develop such a perspective, building on this existing plan, involves the use of a model as a framework to describe the structure and function of an ecosystem.
For example, a conceptual model of the aquatic ecosystem in Lake Hazen is proposed in Figure 3. Based on literature surveyed for this paper, the model: i.) illustrates the effects of physical variables on net primary production (NPP) and habitat availability for aquatic species, and ii.) suggests diatom species as an integrative, biological indicator of the above phenomena. Generally, the model shows that a pulse of phytoplankton NPP occurs prior to ice-out, limited by availability of light (McLaren 1964). Timing and extent of ice-out is determined by wind and temperature in June, and the bulk of NPP occurs following that (Welch 1996). The extent of ice-out govern habitat availability; if more water is open, pelagic diatoms will become more numerous, if not, shallow-water diatom species will predominate (Smol 1994).
Two components of this model are being monitored already: temperature and wind. Additional monitoring should focus on the relationship between light transmission and NPP, and on diatom species composition, both present and historical. These systems are not static: diatoms are a powerful tool for paleolimnological investigations (Smol 1992, 1995), and the continuation of such studies would provide a temporal dimension for interpreting monitoring data within the context of past conditions. Sediment core samples taken for these studies have been used to provide details on contaminant history as well. Detailed bathymetric mapping is definitely required before sediments are re-sampled, since the cores taken to date may have come from slumped sediments (Lockhart, pers. comm.). Deane's lost 1958 bathymetry data has been found (S. Blasco, pers. comm.), and should prove useful for core sample planning.
Other models, possibly linked, could be constructed to guide monitoring efforts for the higher-level aquatic and terrestrial components of the LHE. Models such as presented here are not absolute, and indeed may not even be correct, but they can provide consistency and identify information gaps. Relationships between, for example June temperature, wind and date of ice-out can be extrapolated from literature, but should not be accepted blindly. Specific, focused research projects could be initiated to test and clarify functional relationships and fill knowledge gaps.
Other monitoring topics, mentioned earlier, include precipitation, net radiation, hydrometry and glacial mass balance. These could be integrated into a preliminary energy budget for the LHE. Breeding bird surveys, and population dynamics of selected species should be monitored as well. Temporally, winter is a large unknown for all but remotely- monitored subjects. Given the current fiscal climate, a multidisciplinary overwintering party in the LHE, repeating and building on observations made 40 years ago during the International Geophysical Year, is unlikely to be feasible. Additionally, the expense of Arctic research is itself a compelling reason to plan, coordinate and replicate field studies. Effort should be made to compare, calibrate and ground-truth climate, hydrometry and satellite image data, whenever possible.
Synthesising diverse data in order to produce either a one-time ecological assessment (this paper, for example) or detect long-term trends is a difficult task. An integrated monitoring program in the Lake Hazen Ecosystem would have the considerable benefit of existing previous work, but even in this relatively simple system too much is unknown to have confidence in even the most obvious trend: no change. A framework for monitoring, possibly provided by a model of ecosystem processes, is required in order to ask appropriate practical questions and reach reliable conclusions.
Summary
An abrupt climatic change appears to have occurred in the High Arctic since the 18th Century, which may have drastically changed the aquatic environment of Lake Hazen. Long range atmospheric transport has introduced low levels of organic, heavy metal and radionuclide contaminants into the Lake Hazen Ecosystem. Water chemistry appears largely unchanged over four decades. The relatively high alkalinity of Lake Hazen means that it is not vulnerable to acidification. However, this is probably not a major concern because of the lake's extremely high latitude and distance from pollution sources. Arctic char populations appear to have remained stable over 40 years, and there is no evidence for extinction or immigration of terrestrial fauna over the same time period. Human presence is historically part of the LHE, and harvest impacts have been limited. The interspecific relationships which once existed between humans and their prey species in the LHE are unlikely to be reestablished in any form resembling their previous states, given present technology and the rapidly growing population of Nunavut.
Overall, there is no evidence to suggest any recent significant change in the health of the Lake Hazen Ecosystem. However, this cannot be regarded as conclusive, since the potential for ecosystem impairment does exist, and "absence of evidence is not evidence of absence". Comprehensive surveys or monitoring for anthropogenic stresses are lacking. Given available evidence only, the system may be as pristine (sensu Schindler 1987) as anywhere on earth. Human impacts are present and measurable, but to date their effects on the Lake Hazen Ecosystem appear minimal.
Acknowledgements
Environment Canada's Ecological Monitoring and Assessment Network financially supported the development of this paper. Parks Canada and the Polar Continental Shelf Project supported the author's fieldwork on several projects in Ellesmere Island National Park Reserve in 1996. Lou Comin (Parks Canada) encouraged and supported this endeavour. Clint Johnson (Mycologue Consultants) provided research assistance and support. Phil Wilson (BDW Associates) provided the maps. For their ideas, comments and discussions, I thank Barry Troke and Renee Wissink (Parks Canada), Murray Jones and Doug Halliwell (Environment Canada), John Babaluk, Steve Blasco, Jim Johnson, Lyle Lockhart, Derek Muir, and James Reist (Department of Fisheries and Oceans), Claude Labine (Campbell Scientific Canada, Ltd.), Marianne Douglas (University of Toronto), John Smol (Queens University), and Paul Hamilton (Canadian Museum of Nature). Bryce Kendrick (Mycologue Consultants) reviewed this manuscript. Throughout the development of this paper, many of these people inspired me with their enthusiasm and reverence for the unique, fragile beauty of Lake Hazen.
Literature Cited
Babaluk, J.A., Wissink, R., Troke, B. and Clark, D. (in prep). Summer movements of Arctic char (Salvelinus alpinus) in Lake Hazen, Ellesmere Island, NWT.
Barr, D. 1991. Back from the brink: the road to muskox conservation in the Northwest Territories. Arctic Institute of North America, Komatik Series no. 3. Calgary, AB. 127p.
Bednarski, J. 1991. Chapter 3, Geomorphology. in Parks Canada. 1994. Resource Description and Analysis- Ellesmere Island National Park Reserve. Parks Canada, Dept. of Canadian Heritage, Winnipeg, MB. pp. 3-1 - 3-115.
Bliss, L.C. (ed.) 1977. Truelove Lowland, Devon Island, Canada: a High Arctic ecosystem. University of Alberta Press, Edmonton, AB.
Deane, R.E. 1958. Pleistocene geology and limnology, p. 19-23. in Operation Hazen: narrative and preliminary reports for the 1957 season. Def. Res. Board Can., Dir. Physical Res. (Geophysics) Hazen 2.
Dick, L., Adams, G. and Sutherland, P. 1994. Chapter 10, Archaeology and History. in Parks Canada. 1994. Resource Description and Analysis- Ellesmere Island National Park Reserve. Parks Canada, Dept. of Canadian Heritage, Winnipeg, MB. pp. 10-1 - 10-78.
Douglas, M., Smol, J. and Blake, W. 1994. Marked post-18th century environmental change in High Arctic ecosystems. Science 266: 416-419.
France, R.L. 1992.The Lake Hazen trough: a late winter oasis in a polar desert. Biol. Cons. 1992. 149-151.
France, R.L., Svoboda, J. and Taylor, H.W. 1993. Latitudinal distribution of cesium-137 fallout in 1990 on Saxifraga oppositifolia from Ellesmere Island, Canada. Can. J. Bot. 71: 708-711.
Gould, J. 1988. A comparison of avian and mammalian faunas at Lake Hazen, Northwest Territories in 1961-62 and 1981-82. Can. Field Nat. 102: 666-670.
Gregor, D. and Dahl, M. 1990. Final Report on the 1989/1990 Lake Hazen Water Quality Study. Parks Canada, Winnipeg, MB. 46pp.
Halden, N.M., Babaluk, J.A., Kristofferson, A.H., Campbell, J.L., Teesdale, W.J., Maxwell, J.A. and Reist, J.D. 1996. Micro-PIXE studies of strontium zoning in Arctic char otoliths: migratory behaviour and stock discrimination. Nucl. Instr. and Meth. B 109/110: 592-597.
Hamilton, P.B., Lean, D.R.S. and Poulin, M. 1994. The physicochemical characteristics of lakes and ponds from the northern regions of Ellesmere Island. in Hamilton, P.B. (ed.) Proceedings of the Fourth Arctic-Antarctic Diatom Symposium (Workshop), Canadian Museum of Nature, Ottawa, Ontario, Canada. September 18-21, 1993. Dept. Of Fisheries and Oceans, Ottawa, ON. 139 pp.
Hattersley-Smith, G. 1974. North of Latitude Eighty. Canada Defence Research Board, Ottawa, ON. 121p.
Hattersley-Smith, G. and Lotz,J.R. 1961. Transport, equipment and stores used during "Operation Hazen", 1957-59. Polar Record 10: 372-381.
Hobson, K.A. and Welch, H.E. 1995. Cannibalism and trophic structure in a high Arctic lake: insights from stable-isotope analysis. Can. J. Fish Aquat. Sci. 52: 1195-1201.
Jackson, C.I. 1959. The meteorology of Lake Hazen, N.W.T. Part 1. Analysis of the observations. Arctic Meteorology Research Group, McGill University, Montreal. Publication in Metorology No. 16. Defence Research Board, Ottawa: Report D Phys. R (G) Hazen 9, p. 195-295.
Johnson, C. 1997. Lake Hazen Aquatic Ecosystem Modelling, Ellesmere Island National Park Reserve. Contract Progress Report, February 1997. Parks Canada, Pangnirtung, NT. 8pp.
Johnson, L. 1983. Homeostatic characteristics of single species fish stocks in Arctic lakes. Can. J. Fish Aquat. Sci. 40: 987-1024.
Johnson, D.R. and Agee, J.K. 1988. Introduction to ecosystem management. in Agee, J.K. and Johnson, D.R. (eds) 1988. Ecosystem Management for Parks and Wilderness. University of Washington Press, Seattle, WA. pp. 3-14.
Karr, J.R. 1993. Measuring biological integrity: lessons from streams. in Woodley, S., Kay, J. And Francis, G. (eds) 1993. Ecological Integrity and the Management of Ecosystems. St. Lucie Press. pp. 83-104.
Kelsall, J.P. 1984. The status of muskoxen in Canada with a review of some related subjects. Parks Canada Contract Report 83-78. Parks Canada, Ottawa, ON. 69p.
Kevan, P.G., Forbes, B.C. Kevan, S.M. and Behan-Pelletier, V. 1995. Vehicle tracks on high Arctic tundra: their effects on the soil, vegetation and soil arthropods. J. App. Ecol. 32: 655-667.
LaFarge-England, C. 1989. The contemporary moss assemblages of a High Arctic upland, southern Piper Pass, northern Ellesmere Island, NWT. Can J. Bot. 67: 491-504.
Lockhart, W.L., Wagemann, R., Tracey, B., Sutherland, D., and Thomas, D.J. 1992. Presence and implications of chemical contaminants in the freshwaters of the Canadian Arctic. Sci. Tot. Env. 122: 165-243.
McCanny, S. And D. Henry. 1995. Ecological monitoring: a handbook for Prairie and Northern National Parks. Dept. of Canadian Heritage, Winnipeg, MB. 80pp.
McLaren, I.A. 1964. Zooplankton of Lake Hazen Ellesmere Island, and a nearby pond, with special reference to the copepod Cyclops scutifer Sars. Can. J. Zool. 42: 613-629.
Molau, U. and Mølgaard, P. 1996. ITEX Manual (2nd ed.). Danish Polar Center, Copenhagen, Denmark. 111pp.
Muir, D. and Lockhart, L. 1992. Contaminant trends in freshwater biota. in Environmental Studies No. 68. Synopsis of Research Conducted Under the 1991/92 Northern Contaminants Program. Minister of Indian Affairs and Northern Development, Ottawa. pp. 121-125.
Muir, D. and Lockhart, L. 1993. Contaminant trends in freshwater biota. in Environmental Stidues No. 70. Synopsis of Research Conducted Under the 1992/93 Northern Contaminants Program. Minister of Indian Affairs and Northern Development, Ottawa. pp. 121-125.
Muir, D., Grift, N.P., Lockhart, W.L., Wilkinson, P., Billeck, B. and Brunskill, G.J. 1995. Spatia trends and historic profiles of organochlorine pesticides in Arctic lake sediments. Sci. Tot. Env. 160/161: 447-457.
Nettleship, D.N. and Maher, W.J. 1973. The avifauna of Hazen Camp, Ellesmere Island, NWT. Polarforschung 43: 66-74.
Oliver, D.R. and Corbett, P.S. 1966. Aquatic habitats in a High Arctic locality: the Hazen Camp study area Ellesmere Island, N.W.T. Def. Res. Board Can., Dir. Physical Res. (Geophyics) Hazen 26. 172 pp.
Parks Canada. 1994. Resource Description and Analysis- Ellesmere Island National Park Reserve. Parks Canada, Dept. of Canadian Heritage, Winnipeg, MB.
Reist, J.D., Gyselman, E., Babaluk, J.A., Johnson, J.D. and Wissink, R. 1995. Evidence for two morphotypes of Arctic char (Salvelinus alpinus (L.)) from Lake Hazen, Northwest Territories, Canada. Nordic J. Freshw. Res. 71: 396-410.
Remmert, H. 1980. Arctic Animal Ecology. Springer-Verlag. N.Y. 250pp.
Savile, D.B.O. and Oliver, D.R. 1964. Bird and mammal observations at Hazen Camp, northern Ellesmere Island, in 1962. Can. Field Nat. 78: 1-7.
Schindler, D. 1987. Detecting ecosystem responses to anthropogenic stress. Can. J. Fish. Aquat. Sci. 44: 6-25.
Smol, J. 1992. Paleolimnology: an important tool for effective ecosystem management. Journal of Aquatic Ecosystem Health 1: 49-58.
Smol, J. 1995. Paleolimnology proxy climate data from freshwater Arctic diatoms. Verh. Internat. Verein. Limnol. 23: 837-844.
Steedmann, R.J. 1988. Modification and assessment of an index of biotic integrity to quantify stream quality in southern Ontario. Can. J. Fish. Aquat. Sci. 45: 492-501.
Svoboda, J. and B. Freeman. (eds.) 1994. Ecology of a polar oasis: Alexandra Fiord, Ellesmere Island, Canada. Captus University Publications, Toronto, ON. 281 pp.
Tarnocai, C.T. and Gould, J. 1996. Ecosystem and Trafficability Monitoring for Ellesmere Island National Park Reserve (5-year evaluation). Ellesmere Island National Park Reserve, Pangnirtung, NT. 138pp.
Tener, J.S. 1959. Wildlife Studies. in Operation Hazen: preliminary reports 1957, 1958. Defence Research Board, Canada. Report D. Phys. R(G) Hazen 4. pp. 80-82.
Thompson, P. 1989. Chapter 2, Climate. in Parks Canada. 1994. Resource Description and Analysis- Ellesmere Island National Park Reserve. Parks Canada, Dept. of Canadian Heritage, Winnipeg, MB. pp. 5-1 - 5-78.
Trettin, H.P. 1989. Chapter 2, Geology. in Parks Canada. 1994. Resource Description and Analysis- Ellesmere Island National Park Reserve. Parks Canada, Dept. of Canadian Heritage, Winnipeg, MB. pp. 2-1 - 2-52.
Welch, H.E. 1996. Limarctic: Arctic Freshwater Ecology. CD-ROM. Center for Earth Observation Science (CEOS), Dept. of Geography, Univ. Of Manitoba, Winnipeg, MB.
Woodley, S.J. 1993. Assessing and monitoring ecological integrity in parks and protected areas. PhD Thesis. University of Waterloo, Waterloo, ON. 167p.
