ACADIA NATIONAL PARK

ASSESSMENT OF LONG-TERM AIR QUALITY PROGRAMMATIC, MONITORING AND RESEARCH NEEDS

NOVEMBER 2004

Tonnie Maniero Air Quality Ecological Effects Coordinator National Park Service Northeast Region

Bob Breen Biologist National Park Service Acadia National Park TABLE OF CONTENTS

LIST OF FIGURES ...... iii

LIST OF TABLES ...... iii

EXECUTIVE SUMMARY ...... iv

I. INTRODUCTION ...... 1

II. BACKGROUND ...... 3 AREA DESCRIPTION ...... 3 ATMOSPHERIC DEPOSITION ...... 13 Wet Deposition Monitoring ...... 13 Dry Deposition Monitoring ...... 23 Fog/Cloud Deposition Monitoring ...... 26 Deposition Modeling ...... 26 Deposition Effects ...... 27 Terrestrial ...... 27 Freshwater ...... 29 EstuarinelMarine ...... 32 Previous Recommendations and Unfunded Proposals ...... 33 Deposition Summary ...... 34 AIR TOXICS ...... 35 Air Toxics Ambient Monitoring ...... 35 Mercury Deposition Monitoring ...... 36 Air Toxics Deposition Modeling ...... 39 Air Toxics Effects ...... 39 Terrestrial ...... 39 Freshwater ...... 41 EstuarinelMarine ...... 41 Wildlife ...... 42 Previous Recommendations and Unfunded Proposals ...... 47 Air Toxics Summary ...... 49 OZONE ...... 49 Ozone Ambient Monitoring ...... 49 Ozone Effects ...... 50 Terrestrial ...... 51 Previous Recommendations and Unfunded Proposals ...... 55 Ozone Summary ...... 55

i III. LONG-TERM NEEDS ASSESSMENT ...... 57 PROCESS ...... 57 RECOMMENDATIONS ...... 58 Programmatic Category ...... 59 High Priority Category ...... 60 Medium Priority Category ...... 61 Low Priority Category ...... 61

IV. LITERATURE CITED ...... 63

APPENDIX A. LIST OF ROUND 1 REVIEWERS ...... 71

APPENDIX B. LIST OF MEETING PARTICIPANTS ...... 73

APPENDIX C. LIST OF ROUND 2 REVIEWERS ...... 75

ii LIST OF FIGURES

Figure 1. Map of Acadia NP ...... 4 Figure 2. Soil pH at Acadia NP ...... 5 Figure 3. Ecological systems of Acadia NP ...... 7 Figure 4. Named lakes and ponds, Mount Desert Island ...... 8 Figure 5. Water resources, Isle au Haut ...... 9 Figure 6. Water resources, Schoodic Peninsula ...... 10 Figure 7. Location of air quality monitoring sites at Acadia NP ...... 12 Figure 8. NADPINTN annual S04 wet deposition at Acadia NP ...... 14 Figure 9. NADPINTN annual average S04 wet concentration at Acadia NP ...... 14 Figure 10. NADPINTN annual N03 wet deposition at Acadia NP ...... 15 Figure 11. NADPINTN annual average N03 wet concentration at Acadia NP ...... 15 Figure 12. NADPINTN annual N~ wet deposition at Acadia NP ...... 16 Figure 13. NADPINTN annual average N~ wet concentration at Acadia NP ...... 16 Figure 14. NADPINTN annual Ca wet deposition at Acadia NP ...... 17 Figure 15. NADPINTN annual average Ca wet concentration at Acadia NP ...... 17 Figure 16. NADPINTN annual Mg wet deposition at Acadia NP ...... 18 Figure 17. NADPINTN annual average Mg wet concentration at Acadia NP ...... 18 Figure 18.2003 nationwide NADPINTN annual S04 wet deposition ...... 21 Figure 19.2003 nationwide NADPINTN annual average S04 wet concentration ...... 21 Figure 20. Trends in annual average S04 wet concentration at NPS NADPINTN sites .. .22 Figure 21. Trends in annual average N03 wet concentration at NPS NADPINTN sites .. .22 Figure 22. 1999-2001 trends in wet and dry S deposition at Acadia NP ...... 24 Figure 23. 1999-2001 trends in total S deposition at Acadia NP ...... 24 Figure 24. 1999-2001 trends in wet and dry N deposition at Acadia NP ...... 25 Figure 25. 1999-2001 trends in total N deposition at Acadia NP ...... 25 Figure 26. 2003 nationwide MDN annual mercury wet deposition ...... 38 Figure 27.2003 nationwide MDN annual average mercury wet concentration ...... 38 Figure 28. Trends in I-hour peak ozone concentrations at NPS sites ...... 51 Figure 29. July 1,2001 8-hour peak ozone concentrations in the Northeast U.S ...... 51

LIST OF TABLES

Table 1. Ambient monitoring at Acadia NP ...... 11 Table 2. NADPINTN annual wet deposition at Acadia NP ...... 19 Table 3. NADPINTN annual average wet concentration at Acadia NP ...... 20 Table 4. CASTNet annual dry deposition at Acadia NP ...... 23 Table 5. Top ten VOC monitored at Acadia NP, 1997-2000 ...... 36 Table 6. Wet mercury deposition and average concentration at Acadia NP ...... 37 Table 7. Maximum I-hour and 8-hour ozone concentrations at Acadia NP ...... 50 Table 8. Plant species sensitive to ozone at Acadia NP ...... 54 Table 9. Ranking criteria for air quality projects at Acadia NP ...... 58

111 EXECUTIVE SUMMARY Acadia National Park (NP), as a Class I air quality area, is afforded special air quality protection by the 1977 amendments to the federal Clean Air Act. Since 1979, the park has conducted a comprehensive program that includes 1) ambient air quality monitoring and research; 2) research and monitoring of the effects of air pollutants on visibility, surface water chemistry, soils, sediments and aquatic and terrestrial biota; and 3) public outreach and education regarding air quality. Collected data are used to assess the current and potential effects of air pollution on natural resources in Acad,ia NP.

In October 2002, staff of Acadia NP and the National Park Service (NPS) Northeast Regional Office initiated a process to assess long-term programmatic, monitoring and research needs relative to park air quality. The process involved both independent and group evaluations, and included a number of NPS and non-NPS participants. The resulting report, completed in fall 2004, is divided into two main sections.

Section II, Background, summarizes the extensive ambient air quality data sets collected in and near the park through spring 2004, including wet, dry and fog/cloud (occult) deposition of anions, cations and mercury, and ambient concentrations of ozone and volatile organic compounds. Section II also contains brief summaries of the air pollution effects-related research and monitoring that has taken place in and near the park. Researchers have investigated the effects of 1) atmospheric deposition on park ponds, streams and estuaries, 2) mercury on ecological processes and park biota, and 3) ozone and deposition on park vegetation. Results indicate loss of buffering capacity in park surface waters due to atmospheric deposition and elevated mercury concentrations in fish, amphibians, and piscivorous birds and mammals.

Section III, Long-term Needs Assessment, describes the assessment process in detail, and discusses prioritized long-term air quality programmatic, monitoring and research needs. The section also includes a list of criteria that will be used by staff at Acadia NP to evaluate the usefulness of future project proposals. Continuation of existing ambient and surface water chemistry monitoring is a high priority programmatic need, and mercury will be a focal pollutant for future air pollution effects monitoring and research. NPS staff view the long-term needs assessment as an iterative process. Because the science of air pollution chemistry and effects is a rapidly-advancing field, Acadia NP staff intend to revisit the assessment every five to ten years to add new projects, re-prioritize projects, and reflect any changes in emphasis or direction of the air quality program at Acadia NP.

iv I. INTRODUCTION Acadia National Park (NP), designated in 1929, is comprised ofa cluster of islands on the Maine coast. Steep slopes of deciduous and coniferous forest rise above the park's rocky shoreline. Acadia NP includes a wide variety of freshwater, estuarine, forest, and intertidal resources.

Under the 1977 amendments to the federal Clean Air Act, Congress designated Acadia NP a Class I air quality area. The Class I designation affords the park special legal protection for its air quality and related resources. It provides the National Park Service (NPS) with an affirmative responsibility to protect the air quality and related values (i.e., visibility, soils, vegetation, surface waters, wildlife, and cultural resources) in Acadia NP from the adverse impacts of air pollution. The NPS uses this affirmative responsibility, for example, to review air quality permit applications for sources proposed near the park to ensure increased emissions will not harm park resources.

In 1979, in response to the 1977 Clean Air Act Amendments, an air resources management program was initiated at Acadia NP. This program has become one of the most comprehensive in the NPS. The primary goal of the air resources management program at Acadia NP is to provide managers with science-based information related to the condition of park resources. Specific objectives are to 1) identify and establish baseline conditions for key air quality indicators, 2) determine air quality-related changes and trends over time, 3) provide scientifically-valid research and monitoring data to determine adverse impacts on park resources, and 4) provide data and information necessary to a) make decisions regarding the potential consequences of new air pollution sources proposed near the park, and b) support changes in state and federal air quality regulations that will better protect park air quality and air pollution­ sensitive resources. An important component of the air resources management program has been to educate the public and potential collaborators about Acadia NP's air resource issues. This outreach effort is accomplished through published technical reports and journal articles, park interpretive displays and brochures, newspaper articles, science seminars, and the park's natural resource management website.

A number of ambient air quality parameters are monitored in the park. Park staff also monitor freshwater chemistry indicators of acidification and eutrophication. Many studies have investigated the effects of air pollutants on biological resources and ecological processes in the park. Thanks to research and monitoring funded and conducted by other federal agencies, the Maine Department of Environmental Protection (MDEP), universities, and private organizations, as well as the NPS, a great deal of information has been collected regarding the effects of air pollutants on many resources in Acadia NP.

Because of its Class I designation, visibility impairment is a significant concern at the park, and a great deal of emphasis has been placed on identifying the amount and causes of visibility impairment. Less is known about the ecological and biological effects and implications of air pollution at Acadia NP, so the long-term needs assessment focused on collecting that type of information. The assessment was framed by three key questions. First, what have we learned to date from data collected in and near the park? Second, what are the gaps in information? Third, is there any type of data collection Acadia NP is uniquely suited for that would contribute to the overall information base of the national NPS air quality program?

1 NPS staff enVISIon many uses for the air quality needs assessment. It is a tool for communicating synthesized air quality data, as well as information needs, to universities, federal and state agencies, and other potential partners. It can be used to leverage support for projects whose benefits extend beyond the boundaries of Acadia NP. NPS staff will also use the assessment to solicit and develop proposals for monitoring and research, as well as to help them . evaluate the merit of proposals submitted independently to the park.

Section II, Background, contains a brief description of aquatic and terrestrial resources in Acadia NP. It includes summaries of available wet deposition, dry deposition, mercury deposition, and ozone and volatile organic compound data collected in the park. When possible, for context, the park data are placed in a regional or national perspective. Section II includes brief summaries of past and ongoing air pollution effects studies conducted in and near Acadia NP. It also includes descriptions of unfunded project proposals that have been submitted to the park, as well as recommendations for additional monitoring and research discussed in final project reports. Studies are classified under the categories of Terrestrial, Freshwater, EstuarinelMarine or Wildlife. Note that many of the projects at Acadia NP have investigated watershed processes or bioaccumulation, and so do not fit neatly into these categories.

Section III, Assessment of Long-term Needs, describes in detail the process used for the assessment and discusses the identified prioritized projects and data needs. In brief, the assessment was conducted through an iterative process. First, Section II of the report was sent to a group of subject matter experts who have not been directly involved with past and ongoing projects in Acadia NP. The experts provided recommendations for additional air pollution­ related monitoring and research. In a subsequent workshop involving NPS staff from Acadia NP and the Northeast Regional Office, as well as staff from the MDEP, the U.S. Environmental Protection Agency (EPA), and the U.S. Fish and Wildlife Service (FWS), participants reviewed and refined the subject matter expert recommendations, composed a set of project ranking criteria, and used the criteria to develop a prioritized description of needed projects. Sections II and III were sent out for another round of review, this time by natural resource managers, then reviewer comments were incorporated into the final report. The air quality assessment will be revisited at five-to-ten year intervals to remove funded projects from the list, add new project statements, and reflect any changes in program emphasis or direction at Acadia NP.

2 II. BACKGROUND AREA DESCRIPTION The following brief area description is excerpted from the Acadia NP Water Resources Management Plan (Kahl et al. 2000) and Acadia NP Vegetation Mapping Program (Lubinski, Hop and Gawler 2003).

Acadia NP occupies rocky headlands on the Maine coast, including Cadillac Mountain, which at 1,530 feet (466 m) is the highest point on the U.S. Atlantic coast. The park encompasses approximately 47,633 acres (19,291 ha) in three primary units on Mount Desert Island, Isle au Haut, and the Schoodic Peninsula (Figure 1). Smaller outlying islands are also part of the park. The largest part of Acadia NP is found on Mount Desert Island, where the park occupies almost half of the island. Isle au Haut lies west and seaward of Mount Desert Island, 5 miles (8 km) south of Stonington, and is accessible only by boat. Roughly half of the island is part of the park. Schoodic Peninsula is located 5 miles (8 km) east of Mount Desert Island on the eastern shore of Frenchman Bay. With three million visitors per year, Acadia is one of the most heavily visited national parks.

The park has a maritime climate, with cool weather and frequent fog. Due to its location, Isle au Haut is subject to a more pronounced maritime climate than Mount Desert Island. At Bar Harbor, on Mount Desert Island, rain averages about 49 inches (123 cm) annually, and snow about 5 feet (1.5 m). Temperatures can range from -16 0 F (_9 0 C) in winter to 105 0 F (41 0 C) in summer, with a mean annual temperature of 460 F (8 0 C). The coast of Maine differs from inland portions of the state in having cooler summers, warmer and wetter winters, a narrower range of temperature extremes, a longer frost-free season, and less snowfall. Seasonal variation in weather patterns affects the intensity and duration of rainfall in the park. Convective storms are more common in summer; these produce intense rainfall of short duration compared with the broad frontal systems that tend to produce longer periods of less intense rainfall at other times of the year. Limited research conducted on microclimates within the park suggests that there is considerable local variation in temperature, precipitation and evaporation.

The marine environment is an important part of the park setting. The cool ocean waters surrounding Acadia NP have a profound effect on climate, atmospheric deposition, scenery, habitat and the diversity of plant and animal species. Marine waters support a variety of life forms, from tidepool creatures to sea mammals. Frenchman Bay lies to the east of Mount Desert Island and Blue Hill Bay to the west, and estuaries include Northeast Creek, Somes Sound and Bass Harbor Marsh. Many terrestrial birds and mammals of Acadia NP rely on the saltwater resource for habitat and food. The NPS does not have any management authority in marine waters beyond the intertidal zone.

On Mount Desert Island, glacial and post-glacial activity has left a series of north-south trending ridges separated by deep U-shaped valleys. Extensive areas are treeless, standing out sharply above the predominant forest cover of the region. Upland soils are mostly thin and granitic, with many areas of bedrock or talus where soil development is minimal at best. All park soils have a pH of 6.5 or lower (Figure 2). Wetlands are underlain by marine deposits or poorly drained tills and include both mineral soil and organic soil wetlands. Soil survey and wetlands classification data are available for the park.

3 Isle au Haut

Acadia National Park Non-park lands

Figure 1. Map of Acadia NP (from Kahl et al. 2000)

4 i I (J S RNa pH of SolI Onlll .a "i - Rri111lUY4;5. I . .. f -~.)' u ~ =·~ ..~I • --CamJln8 _ S;$ I Labs & PelmcfIi. J

Figure 2. Soil pH at Acadia NP

Acadia NP lies at the southern edge of the spruce-fir-northern hardwoods region. The vegetation reflects this transitional position with several species and plant communities at the edge of their ranges. Some areas exhibit a boreal influence. Much of the undeveloped region is characterized by various expressions of spruce-fir forests or forests in transition toward spruce-fir forests. Schoodic Peninsula has distinctive plant associations including stands of jack pine (Pinus banksiana) and plants of sub-arctic affinity growing at the southern limit of their range.

A history of major fires, i.e., large fires at 100 to 150 year intervals, has strongly influenced park vegetation. The 1947 Bar Harbor fire was the last major fire, which burned approximately one third of Mount Desert Island. Areas unburned by the 1947 Bar Harbor fire are dominated by spruce-fir forests. Red spruce (Picea rubens) is predominant and balsam fir (Abies balsamea) is common. White spruce (Picea glauca) occurs along shoreline areas, and black spruce (Picea mariana) is found in bog areas in association with eastern larch (Larix laricina). Mixed conifer stands with scattered hardwoods are dominated by red spruce with northern white cedar (Thuja occidentalis), balsam fir, red maple (Acer rubrum), paper birch (Betula papyri/era), red pine

5 (Pinus resinosa) and white pine (Pinus strobus) present. Sheltered moist sites in Acadia NP valleys support small stands of northern hardwoods dominated by beech (Fagus grandifolia), with sugar maple (Acer saccharum) and other hardwoods forming dense canopy and seedlings and saplings of beech, striped maple (Acer pennsylvanicum) and red spruce forming the understory. The fire of 1947 extensively destroyed softwood forest stands on eastern Mount Desert Island allowing regeneration of hardwood, birch-aspen communities with quaking aspen (Populus tremuloides), bigtooth aspen (Populus grandidentata), paper birch and gray birch (Betula populifolia). Vegetation mapping in the late 1990s identified 53 naturaVsemi-natural vegetation communities and 19 ecological systems (Figure 3) in the park.

The hydrology of the park is influenced by the steep slopes, thin soils and maritime climate. Acadia NP's watersheds are small, short and steep, averaging less than 3 miles (5 km) from headwaters to the sea. Precipitation and frequent sea fog deliver moisture throughout the year. However, streamflows are usually very low in late summer and early fall because of rapid runoff and poor moisture retention by the upland soils.

There are 12 major watershed systems that drain the interior of Mount Desert Island. The alignment of these watershed systems roughly parallels the north-south orientation of the park's ridges and valleys. These drainages are characterized by bold topographic relief of up to 1,477 feet (450 m) across a distance of only 4-5 miles (6-8 km). Most watersheds of the park lie at least partially outside the park boundary. The park owns the upland portions of most watershed systems.

Water resources associated with the park include 14 Great Ponds (those water bodies larger than 10 acres (4 ha), 9 smaller ponds, more than two dozen named streams, 10 named wetland areas, and five named springs (Figures 4, 5 and 6). The park contains 41 miles (65 km) of rocky shoreline, about 2,600 acres (1,052 ha) oflakes and ponds, and approximately 4,127 acres (1,670 ha) of wetlands. Freshwater lakes in the park span the typical range of water quality found in Maine. The larger lakes such as Eagle Lake and Jordan Pond are generally clear and oligotrophic, with circumneutral pH.

6 L• .:8:15.0.:1:l,7.00 __ .3'i40=O==5::,1.0.0 __6,8~hometers

Ecological Systems ~ CUllural Vegetation _ Laurenllan-Acadlan Acidic Swamp Acadian Coastal Salt Marsh Land Use _ Laurentian-Acadian Alkaline Fen .. Acadian Lowland Spruce-Flr-Hardwood Forest l1l'i Laurentian-Acadian Acidic Basin Fen _ Laurentian-Acadlan Northern Hardwoods forest _ Acadian Maritime Bog Laurentian-Acadian Acidic Cliff and Talus Laurentian-Acadian Pine-Hemlock-Hardwood Forest) Acadian-North Atlantic Rocky Coast .. Laurentian-Acadian Acidic Rocky Outcrop _ Laurentian-Acadian Wet Meadow-5hrub Swamp and Marsh _ Boreal Aspen-Birch Forest III Laurentian-Acadian Acidic Swamp ~ Laurentian-Acadian White PinErR.ed Pine Forest o Non-vegetated Water _ndalZone Acadia Boundary

Figure 3. Ecological systems of Acadia NP (from Northeast Temperate Network Inventory and Monitoring Program)

7 N Watershed boundaries _ Lakes & ponds ilftfj Acadia National Park k~jjiB~ Non-park lands

Figure 4. Named lakes and ponds, Mount Desert Island (from Kahl et al. 2000)

8 /\/Streams -_ Lakes & ponds ~ Wetl~nds (:alustrine/Estuarine) i!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!i;;;;______~2 Mias i%:j'i,~ Acadia NatIOnal Park Non-park lands

Figure 5. Water resources, Isle au Haut (from Kahl et al. 2000)

9 /:V.lnlBrmittent streams /\/ Parennial streams •• Lakes & ponds O!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!0'ji5iiiiiiiiiiiiiiiiiiiiiiil1 Mi Ie s ~ Wetiands (Palustrine/Estuarine) N WaIBrshed boundaries 0.5 1.5 Kilometers ° ~l1 Acadia National Park ~~iiiiiii~~ Non-park lands

Figure 6. Water resources, Schoodic Peninsula (from Kahl et al. 2000)

10 Acadia NP has an extensive and long-term ambient air quality monitoring program. The following "core" parameters are monitored: ozone, sulfur dioxide (S02), nitrogen oxides (NOx), volatile organic compounds (VOC), fine particulates, visibility, meteorology, wet deposition of mercury, and wet and dry deposition ofa number of anions and cations (Figure 7; Table 1). The park also has a long-term surface water monitoring program to detect chemical changes due to atmospheric deposition. In addition to the core ambient air quality monitoring program, additional parameters have been monitored on a short-term basis to collect baseline data, support research projects, or provide input for atmospheric transport models.

T abl e 1 . A m b'lent momtonng at A cad' la NP PARAMETER LOCATION START DATE END DATE Wet Deposition 1 McFarland Hill 1981 present Dry Deposition2 McFarland Hill 1998 present Mercury DepositionJ McFarland Hill 1995 present Ozone (continuous) Cadillac Mountain 1995 present McFarland Hill 1982 present Schoodic 2003 present Meteorology4 Cadillac Mountain 1995 present McFarland Hill 1991 present Sulfur Dioxide (continuousl McFarland Hill 1988 1990 Nitrogen Oxides5 Cadillac Mountain 91,93, 1995- present Volatile Organic Compounds:> Cadillac Mountain 91,93, 1995- present Carbon monoxide Cadillac Mountain 2002 present uyn McFarland Hill 1998 2004 Particulate Matter (Aerosol) McFarland Hill 1988 present Teleradiometer7 McFarland Hill 1980 1986 Transmissometer' McFarland Hill 1987 1994 Nephelometer' McFarland Hill 1993 present 35 mm camera7 Cadillac Mountain 1983 1995 McFarland Hill 1980 1983 Web cameral! Cadillac Mountain 1999 present Surface Water Chemistry9 10 park lakes 1997 present I- .. NatIOnal Atmosphenc DepOSItIOn ProgramlNatIOnal Trends Network 2Clean Air Status and Trends Network 3Mercury Deposition Network 4Includes wind speed, wind direction, temperature and relative humidity 5Continuous and event measurements 6Brewer spectrophotometer 7Technique used to monitor visibility impairment 8Used to interpret current visibility conditions 9 Acidification and eutrophication-related parameters

11 Acadia National Park ~Jational Pal1k Ssr.. icB ,,_, Maine lL8. Department of the Interim ,~ ... ' ·Acadia National Park Air Quality Monitoring Sites

N Legend: Air monttoring sites \'II Active .. Histonc o +2 4 Miles

Figure 7. Location of air quality monitoring sites at Acadia NP

12 ATMOSPHERIC DEPOSITION Wet Deposition Monitoring The National Atmospheric Deposition ProgramlNational Trends Network (NADPINTN) is a nationwide network of precipitation monitoring sites. The network is a cooperative effort between many different groups, including the EPA, U.S. Geological Survey, U.S. Department of Agriculture, NPS and private entities. There are currently more than 200 NADPINTN sites spanning the continental U.S., Alaska, Puerto Rico, and the Virgin Islands.

The purpose of the network is to collect data on the chemistry of precipitation to monitor geographical and temporal long-term trends. The precipitation at each station is collected weekly according to strict clean-handling procedures. It is then sent to the Central Analytical Laboratory in Illinois where it is analyzed for hydrogen (acidity as pH), sulfate (S04), nitrate (N03), ammonium (NH4), and base cations (such as calcium (Ca) and magnesium (Mg». NADPINTN's excellent quality assurance programs ensure that the data remain accurate and precise. Deposition, reported in kilograms per hectare (kglha), varies with the amount of annual on-site precipitation and is useful because it gives an indication of the total annual pollutant loading at the site. Concentration, reported in micro equivalents per liter (J..leq/l), is independent of precipitation amount, therefore, it provides a good indication of whether ambient pollutant levels are increasing or decreasing over time.

A NADPINTN site was installed at McFarland Hill, in Acadia NP, in November 1981 (site ME98, elevation of 499 feet (152 m». In terms of acidifying ions, from 1981 to 2003, wet S04 deposition and concentration decreased at the site, but there was no clear trend in deposition and concentration of wet N03 and NH4, or deposition of total inorganic nitrogen (N). Regarding buffering ions, base cation deposition and concentration, represented by Ca and Mg, appear to have declined at the park during the same timeframe. (Figures 8 through 17; Tables 2 and 3). More information on the NADPINTN program, as well as all available NADPINTN data for Acadia NP, is available at the NADPINTN website (http://nadp.sws.uiuc.edu/).

13 NADPJNTN Sle MEse Annual S04 wet d~ositions, 1961-2003 3D

•

10 • .'

Figure 8. NADPINTN annual 804 wet deposition at Acadia NP (from http://nadp.sws.uiuc.eduD

t4A.DPlNTNi Sfte MESB Annual S04 concentrations, 1961·2003 50

4{1 " .. 30 '*' -I 13- .. iIP • ::J 2D • ... • ... .. HI

&. OJd OO! mQllt~ritarna ,I 'rand! Umt

Figure 9. NADPINTN annual average 804 wet concentration at Acadia NP (from http://nadp.sws.uiuc.eduD

14 NADPINTN Sle ME98 Annual N03 wet d~positiOO'S, 1981-2003 20

Figure 10. NADPINTN annual N03 wet deposition at Acadia NP (from http://nadp.sws.uiuc.edu/)

NADPINTN Site ME98: Annual N03 cCJnCentrations" 198'1-,2003 20 ", • .. u· .. .. '" " ..... 1:1- HI .Ii .. IQ> .. :J ..

5

Figure 11. NADPINTN annual average N03 wet concentration at Acadia NP (from http://nadp.sws.uiuc.edu/)

15 NADPJNTN Sle MEse .Annual NH4 wet depositions, 1981-2003 2.5

;i1,(I' .. • .a. Ii. 1.'5 • ~ .. ... • i HI • Ii

Figure 12. NADPINTN annual NH4 wet deposition at Acadia NP (from http://nadp.sws.uiuc.eduD

NADPmTN Site ME98 Annual NH4 concentrations, 1981-2003 10

• .' .. fi .. -J 1:t .. • .' ::II'" ~ .. • l

O~~--~+-~~-+-r~+-~-+-r~+---~~-+~ t~O 101}2 1B€t4 19@€i~9:DB 1~90 1'992 19$4. 1~ 1I1!!92DDO 2002 10041 .. l\igh:rtbIlD

Figure 13. NADPINTN annual average N~ wet concentration at Acadia NP (from http://nadp.sws.uiuc.eduD

16 NA.DPINTN SIte ME98: .Annual ca wet depositions, 1981-2003 2.0

"- L'S .' lit 'i 1!0 • .. •• ..

:0.5 .. • •

IDJIl 'L..----L--+--+-+---+-+-+--+-+--t--I--I-+-i---1--"--I--"-+-' 100I[I1'9B2 19114 1\iI!lIfI 1'9OB 1!Jill) 1~2 11U14 1!Hlt]; 1@M1201l0 2DIlc2 20041 • Mah:riiDrtDi

Figure 14. NADPINTN annual Ca wet deposition at Acadia NP (from http://nadp.sws.uiuc.edu/)

NADPINTN Site MES8 Annual Cit concentrations~1981w2003 5, •

3, .. ..

11 '

'*' OJd r:mI mue:hriiDrilli ,/ fnnd! Unll'

Figure 15. NADPINTN annual average Ca wet concentration at Acadia NP (from http://nadp.sws.uiuc.edu/)

17 NADP'RlIl'N SIte fA EBB Annum Mg wet depositions, 1981-2003

:Ul .'

Hi ~ .. ... '. .. 'J 1.11) ,. .. (1;5 ... • :il.if1 '---'"--I--+-+---I--i--I--+-+-+-II--t-+-+--I---'--I--"-+--' 1900 ~gD2 1£1114 1Q€1fl 1'9011 1B9a 1%2 1904 1996; 1~ :i!OOO 2002 20(11/1

'" DKi md maah:ritarisai ,1 Tund Unit

Figure 16. NADPINTN annual Mg wet deposition at Acadia NP (from http://nadp.sws.uiuc.eduD

NADPiNTN Site MEBB Amual Mg concentrations, 1981-2003 0.20 .. ,D.Hl ., ... ,...... Q :0;11) .. E .. "- D.l1)5 • • •

,., llihrl, c riluiU. .., Dld md meahritam ,/ fundi Unit

Figure 17. NADPINTN annual average Mg wet concentration at Acadia NP (from http://nadp.sws.uiuc.eduD

18 16.92 15.94 16.52 14.95 16.22 0.79 0.82

1.297 10.29 3.78 I 0.68 7.21 2.56 II 9.79

19 Table 3. NADPINTN annual average wet concentration at Acadia NP (in Jleq/l)

YEA ~M~==~~==~==~~==~~~iF=~ 1982 8.39 1983 1984 1985 1986 1987 27.27 1988 7.16 3.27 12.07 30.52 1989 3.34 5.68 7.04 14.11 30.87 1990 6.00 15.34 30.85

2.30 4.36

Using S04 data collected in 2003 as a typical example, Acadia NP wet deposition and concentration values were comparable to those collected at other NADPINTN sites in Maine, lower than values reported for sites in the Midwest and Mid-Atlantic, and higher than values for sites in the Western U.S. (Figures 18 and 19). Trend data from NPS NADPINTN sites indicate that similar to many parks, S04 concentrations in precipitation decreased at Acadia NP between 1992 and 2002, but N03 concentrations increased (NPS 2002; Figures 20 and 21).

20 Figure 18.2003 nationwide NADPINTN annual 804 wet deposition (from http://nadp.sws.uiuc.edu/)

Figure 19.2003 nationwide NADPINTN annual average 804 wet concentration (from http://nadp.sws.uiuc.edu/)

21 Left Arrow: 1992-2001 Trend RighlArrow: 1993-2002 Trend

ncreaslng Trend, p~.15 ..... • NoTrend • hsufficientOala

Figure 20. Trends in annual average S04 wet concentration at NPS NADPINTN sites (from NPS 2002)

Left Arrow: 1992-2001 Trend RighI Arrow: 1993-2002 Trend

Decreasing Trend, p>O.15

Increasing Trend, p<=O.15 hcreasing Trend, p>O.15 ..... • NoTrend • tlsufficientOata

Figure 21. Trends in annual average N03 wet concentration at NPS NADPINTN sites (from NPS 2002)

22 Dry Deposition Monitoring The Clean Air Status and Trends Network (CASTNet) is the nation's primary source for atmospheric data to estimate dry acidic deposition. Established in 1987, CASTNet now comprises over 70 monitoring stations across the U.S. The majority of the monitoring stations are operated by EPA; however, approximately 20 stations are operated by the NPS in cooperation with EPA. Each CASTNet dry deposition station measures weekly average atmospheric concentrations of S04, N03, NI1J, S02, and nitric acid (HN03); hourly concentrations of ambient ozone; and meteorology. Dry deposition rates are calculated using atmospheric concentrations, meteorological data, and information on land use, vegetation, and surface conditions. Because of the interdependence of wet and dry deposition, all CASTNet sites are located at or near NADPINTN sites.

A CASTNet dry deposition monitor was installed at McFarland Hill in late 1998 (site ACA416, elevation of 499 feet (152 m)). Sulfur (S) and N deposition data are available for 1999 through 2002, and trend data are available for 1999 through 2001 (Figures 22 through 25; Table 4). Further information on the CASTNet program and additional data for Acadia NP is available on the CASTNet website (http://www.epa.gov/castnetD.

Table 4. CASTNet annual dry deposition at Acadia NP (k!~a) YEAR HN0 3 NH4 N03 S02 S04 1999 4.43 0.19 0.21 1.75 0 ..78 2000 2.52 0.09 0.10 1.31 0.37 2001 4.46 0.21 0.15 1.61 0.79 2002 4.62 0.19 0.17 1.67 0.77

A 2001 data summary report (Harding ESE, Inc. 2002) provided dry and total Sand N deposition trends for 1990-2001 for the CASTNet program. The trend analyses were based on data from sites that had been in operation during the entire monitoring period. CASTNet data indicated both dry and total S deposition had declined in the eastern U.S. since 1990. There had been no significant trend in dry N deposition, but because of a slight decrease in wet N deposition, total N deposition in the eastern U.S. had also decreased between 1990 and 2001.

Norton et al. (1988) sampled lakes throughout Maine and compared S04 input from wet deposition to S04 concentrations in lake water. After ruling out geologic sources of S in the lake watersheds, they determined that dry deposition of S to drainage basins of lakes ranged from 0 to 100 percent of wet deposition. Norton et al. concluded there was a gradient of dry S deposition across Maine, with low levels at the coast, and increasing levels as one moved northwest across the state.

One of the recognized problems with the CASTNet dry deposition numbers is that the values are calculated from ambient concentrations and estimated deposition velocities rather than based on actual measurements. The CASTNet estimates are not very reliable for complex terrain, such as occurs in Acadia NP. Weathers (K. Weathers, pers. comm., 2003) is currently investigating the possibility of using throughfall samples, rather than CASTNet estimates, to determine dry deposition. Throughfall samples were collected in 2002 at Acadia NP and nine other forested sites in the eastern U.S. Weathers is comparing estimates of dry and total S deposition via the

23 throughfall method to CASTNet-derived estimates of total deposition (based on combined CASTNet and NADPINTN data). Final results should be available in 2004.

Wet and Dry S Deposftkln ACM1G

1tJ

M«tot' :NUO(il I- Dy-t I- ..... -+1 AMIjM iffIl' 80! lIIIII!IlIiI!I iI:Iy ilOIIi _ WIi'I 804 -- Figure 22. 1999-2001 trends in wet and dry S deposition at Acadia NP (from http://www.epa.gov/castne!D

-- Figure 23. 1999-2001 trends in total S deposition at Acadia NP (from http://www .epa. gOY / castnetQ

24 Wet and DI"y N Deposition ACA41J

.' (i) (Iii .. IX! iii t-~-; t-'i¥llt4

~ by ~ I!iIIiIIlI!III! by NHiI _ D)I N(iI:; IIIIIIIIIIIWtiII,.. IIIIIIIIIIIWMlNm-- -- Figure 24. 1999-2001 trends in wet and dry N deposition at Acadia NP (from http://www .epa. gOY/ castnetD

ToIaI N ~tian ACA,41J

W 00111

h\Jh by ~ I!iIIiIIlI!III! by NHiI _ D)I N(iI:; IIIIIIIIIIIWtiII,.. IIIIIIIIIIIWMlNm -- Figure 25. 1999-2001 trends in total N deposition at Acadia NP (from http://www .epa. gOY/ castnetD

25 Fog/Cloud Deposition Monitoring As part of the nationwide Cloud Water Project, Weathers et al. (1988) collected cloudwater and rainwater samples, on an event basis, in 1984 and 1985 .at 10 non-urban sites in North America. They found cloudwater from eastern u.s. sites was more acidic and had higher concentrations of N03 and S04 than cloudwater from western U.S. sites. Weathers et al. reported cloudwater from Maine had the highest concentrations measured in the study. At most sites, cloudwater was more acidic, and had higher concentrations ofN03 and S04, than rainwater.

Jagels et al. (1989) measured rain and fog chemistry at sites along the Maine coast, including a site at Isle au Haut in Acadia NP. They found that while rain pH and N03 and S04 concentrations were similar between sites, fog pH and N03 and S04 concentrations showed a decreasing gradient from southwest to northeast along the coast.

Deposition Modeling In a current project, Weathers et al. (2001) are attempting to scale up point measurements of total atmospheric deposition to the landscape using empirical data and multi-variate statistical models that use landscape features (e.g., vegetation cover and topography) as independent variables and indices of total deposition as dependent variables. This information, along with information on "base deposition" calculated for the NADPINTN and CASTNet monitoring stations, will then be used to create GIS-based maps of total deposition for Acadia NP. The maps will identify broad­ scale gradients of deposition, as well as hotspots--areas where deposition may be unusually high and ecosystems may be at particular risk. Although the study is focusing on S, N and lead, the models generated should be applicable to other air contaminants that are deposited by similar mechanisms, including mercury, other trace metals, and air toxics. Weathers et al. are measuring S04 in throughfall and lead in surface soil as deposition indices. Throughfall and soil samples were collected at Acadia NP in 2000. Preliminary data indicate total deposition is a function of elevation and vegetation type. The project will be completed in late 2004 and a project report andjoumal publications will be available in 2005.

In an effort initiated by the New England Governors and Eastern Canadian Premiers (NEGIECP), a group of researchers are developing maps of forest sensitivity to Sand N deposition for upland forests in northeast North America (New England GovernorslEastern Canadian Premiers Forest Mapping Group 2001). They will also be estimating sustainable deposition rates-based on long-term loss of base cations--and deposition exceedances for upland forests representative of the region. The pilot phase of the project focused on Vermont and Newfoundland. The pilot phase modeling effort included two levels of detail, a site-specific approach that used on-site model input data, and an ecological unit approach that used regional model input data. Similar to the Weather et al. project described above, the NEGIECP forest mapping project scaled up point measurements of deposition using landform and climatological factors. However, the NEG/ECP researchers used a different model to generate maps of total deposition. Preliminary results identified three factors that led to forest sensitivity: high deposition rates, soils with low mineral-weathering rates, and forests composed predominantly of species with a high energy demand (L. Pardo, pers. comm., 2003). The project pilot phase report should be available in 2004.

26 Deposition Effects Terrestrial Wetmore (1984) collected lichens at Acadia NP in 1983 and analyzed their tissue for S concentrations. He reported that lichen tissue S concentrations were within "typical" limits, and that he found no differences between, or correlations among, collection sites and tissue S concentrations.

Sullivan (1986) performed a lichen study in the park from 1983 to 1985. He evaluated distribution and fertility of known S02-sensitive lichen species, as well as analyzed elemental concentrations in lichen tissues. Sullivan reported concentrations of S and other elements were within ranges reported as background in the literature. Based on the elemental concentrations and fertility and distribution data, he concluded lichens in Acadia NP were not being adversely affected by air pollution.

Stubbs et al. (1988) installed lichen biomonitoring plots at four locations in Maine, including one at Isle au Haut in 1988. Each plot consisted of 10 red spruce tree trunks. They determined lichen health (based on the percent of normal tissue) and species density on each plot. Stubbs et al. found lichen assemblages on inland plots were less diverse than those on coastal plots. They concluded intersite differences in lichen health corresponded to pollution levels and red spruce health.

Stubbs et al. (1990) reevaluated the lichen plots in 1990. They reported no change at the inland sites, and decreased lichen health and diversity at the coastal sites. Stubbs et al. speculated the changes at the coastal sites were due to air pollution.

In conjunction with rain and fog chemistry measurements discussed earlier, Jagels et al. (1989) evaluated foliar injury, i.e., chlorosis and needle drop, of coastal red spruce. They found no significant difference in soil pH between sites with injured and uninjured trees. Jagels et al. speculated that atmospheric N deposition, or possibly N deposition plus ozone, might be the cause of the foliar injury. They hypothesized soil nutrient levels may have been moderating plant foliar response at sites with no injury.

Jagels (1986) also compared tree ring growth between injured and uninjured red spruce at Head Harbor (Isle au Haut), Eastern Head (Isle au Haut), and Roque Island. Tree ring analyses indicated 1955 to 1975 weather conditions were ideal for tree growth; however, red spruce at Head Harbor began to decline during this period. He reported no significant decline in tree ring growth for red spruce at Eastern Head or Roque Island. According to Jagels, red spruce at Head Harbor displayed the greatest amount of foliar injury among the three sites. He reported Head Harbor also had higher ozone concentrations and more acidic fog than the other locations. Jagels saw no evidence of forest pests, and he discounted aluminum toxicity as the cause of the foliar symptoms. He concluded that the foliar injury and growth decline in red spruce at Head Harbor were due to ozone and/or acid fog.

Taylor et al. (1986) studied the influence of ozone, fog chemistry, rain chemistry, and soil type on growth of red spruce seedlings. They collected soil from Acadia NP (location not provided) and from a stand of declining red spruce in the Green Mountains of Vermont. Seedlings were

27 grown in one of the soil types, and then exposed to various ozone concentrations and precipitation treatments for four months. The rain and fog treatments included S04, N03, trace elements and heavy metals. No needle injury was observed in any treatment. Interactive effects of treatments on seedling growth were not notable. Soil type was the only treatment that affected plant growth, with seedlings doing better in the soil from Acadia NP. Chemical analysis indicated soils from the park had higher organic content and base cations and lower aluminum and heavy metals.

McNulty et al. (1990) sampled 11 spruce-fir sites in the northeast U.S., including one on Mount Desert Island, Acadia NP, in 1987 and 1988. They evaluated soil pH, stand mortality and rates of N mineralization and nitrification. McNulty et al. found net mineralization varied widely across the sites and there was no statistically significant relationship between mineralization and deposition. Based on the data from a subset of sites, they concluded N saturation due to atmospheric deposition could be occurring in some spruce-fir forests in the northeast U.S.

In 1988, Percy et al. (1993) studied red spruce at five sites in Maine along a fog acidity gradient. Two sites were on Isle au Haut, two more were on the coast, and one site was inland. They evaluated epicuticular wax amount and wax composition of the spruce needles. Percy et al. found a high correlation between wax production and the amount of fog at a site. They reported no significant differences in wax chemical composition among needles from asymptomatic and symptomatic trees.

Jiang and Jagels (1999) exposed 5-year old red spruce saplings in chamber studies to acid fog (S04 and N03) or control during the 1996 and 1997 growing seasons. They found acid fog exposure caused the needles to leach Ca. To confirm the chamber studies, in 1997, needles were collected from four 15-20 year old red spruce on Isle au Haut and, to serve as a control, from trees in Old Town, Maine. Based on fluorescence microscopy procedures, needles from Isle au Haut had lower membrane-associated Ca concentrations. Jiang and Jagels concluded acid fog could be contributing to Ca leaching in red spruce needles on Isle au Haut.

In 1998, Kahl et al. (2003) initiated an intensive ecological research program, called PrimeNet, using two gauged watersheds at Acadia NP. A large portion of the Cadillac Brook watershed burned severely in 1947, while the Hadlock Brook watershed was not burned. The focus of the research was atmospheric deposition of acids, N, and mercury, and their ecological consequences. The PrimeNet project involved a number of sub-projects that collected the following information: 1) comprehensive baseline information on forest vegetation in the two watersheds, 2) foliar chemistry differences between the watersheds, 3) factors that influenced input of ions to the watershed (Nelson 2002), 4) influence of burn history on nutrient export to coastal waters (Lent et al. Undated), and 5) mercury distribution and mobilization (Amirbahman et al. In review; Johnson 2002). Foliar N concentrations of red maple were not different between watersheds. However, foliar N concentrations were higher for red spruce from the Hadlock watershed than those from the Cadillac watershed. Contrasting results between watersheds were observed for Ca, Mg, and potassium. Kahl et al. concluded soil nutrient availability for plant uptake might differ between watersheds as a function of soil geochemical characteristics and micro-ecological disturbances within each watershed rather than from long-term effects from the 1947 wildfire. Red maple and red spruce foliar aluminum concentrations were higher in the

28 Hadlock watershed than in the Cadillac watershed, indicating higher soil aluminum mobility, which might be a result of lower soil pH in the Hadlock watershed. Kahl et aL concluded that forest stand histories for the two watersheds supported the hypothesis that forest type and fire history influence long-term cycling and storage of atmospheric mercury and N within watersheds. Data showed that fifty years after wildfire at Acadia NP, the burned watershed with hardwood regeneration had significantly lower forest-floor carbon and N concentrations than the unburned watershed dominated by softwoods. Also, the previously burned Cadillac Brook watershed exported less mercury than the unburned Hadlock Brook watershed, indicating that forest fires can have both immediate and long-term effects on mercury availability and bioaccumulation. Results of the PrimeNet projects will be published in a special issue of the journal Environmental Monitoring and Assessment in 2005.

Nelson (2002) collected precipitation and throughfall volume and chemistry data on the Cadillac Brook and Hadlock Brook watersheds in 1999 and 2000 using wet only and continuously-open collectors. Data showed, in general, the highest deposition occurred in fall and summer. Nelson found that in both watersheds, hydrogen, Mg, potassium, N~, and N03 were retained, while Ca and S04 were lost. Nelson concluded that vegetation type was the dominant control on enhancement of precipitation across heterogeneous watersheds, and that differences in watershed and vegetation characteristics control input of water and major ions to the watersheds.

Freshwater Kahl et aL (1993) collected lake chemistry data in Acadia NP from 1982 to 1989 and compared changes in lake chemistry to changes in deposition chemistry. They reported the NADPINTN data showed nonsignificant declining concentrations of all solutes. During the same time frame, 11 park lakes showed a slight increase in acid neutralizing capacity (ANC), a decrease in the sum of base cations, but no decrease in S04 concentrations.

Kahl et aL (1992) used data from the Bear Brook (New Hampshire) and Hadlock Pond Watershed Studies to identify factors that contribute to episodic acidification in Maine streams. They defined episodic acidification as an ANC decline of at least 50 Jleqll, or 50 percent, and storm flow events in which ANC dropped below O. According to Kahl et aI., the factors that contributed to episodic acidification included dilution from increased discharge, sulfuric acid input from precipitation or natural sources, nitric acid input from precipitation or natural processes in upper soil horizons, organic acid input from watershed soils or wetlands, and hydrochloric acid production from salt-effect reactions within watershed soils.

Heath et aL (1993) collected water quality data in Acadia NP from 1988 through 1990 and compared it to data collected at the same sites in 1982 through 1984. The data showed no significant increases in ANC or S04 concentration. Heath et aL reported that major episodic acidification events had been observed on numerous occasions in first-order brooks and second­ order streams in the park. Data indicated the most significant contributing factors to episodic acidification included input of natural acids from soil solutions, and input of sulfuric acid and RN03 from precipitation. Less important mechanisms of episodic acidification included dilution by increased flow, increased N03 concentrations from precipitation or the large soil N pool, and increased export of organic acidity from soils. Heath et aL interpreted many of the episodic acidification events as being due primarily to an ion-exchange salt effect of sodium ion for

29 hydrogen ion in soil solution, and secondarily to dilution, neither of which is directly related to acidic deposition. The salt effect phenomenon was observed principally in first-order, upland sites with thin soils. Heath et al. reported acid precipitation was a contributing, but non­ essential, factor in these episodic acidifications. They were not able to estimate the contribution of acidity in precipitation to salt effect acidifications. Heath et al. also estimated the mass balance for the Upper Hadlock Pond watershed. The data indicated the watershed was exporting products of mineral weathering in amounts similar to other watersheds in eastern Maine. However, Heath et al. found more N was retained in the Upper Hadlock Pond catchment than at two comparable catchments 35 miles (60 km) north of the park. Heath et al. concluded N leaching from the Upper Hadlock Pond terrestrial systems did not appear to be nearly as high as in some other regions of the northeastern U.S.

Kahl (1996) performed a comprehensive water chemistry survey of all 24 lakes and ponds on Mount Desert Island and Isle au Haut in 1995. Kahl reported most lakes on Mount Desert Island were circumneutral; however, Sargent Mountain Pond and Duck Pond were acidic, due to atmospheric deposition and organic acidity, respectively. The lakes on Mount Desert Island were also poorly buffered, and had low aluminum concentrations.

Davis et al. (1994) collected sediment cores from 12 acidic lakes in granitic, forested and uninhabited catchments in northern New England, none of which were in Acadia NP. The cores were used to reconstruct changes in pH and ANC. Trace metal chemistry data (lead, zinc, vanadium, and copper) suggested atmospheric deposition started in New England in the late 1800s to early 1900s. Lead concentration in the cores peaked at about 1970, and concentrations of the other trace metals decreased after the 1960s. Davis et al. concluded the cores indicated the 12 lakes were naturally acidic and had had low ANC values in pre-industrial times. Nevertheless, they reported all the lakes showed additional acidification since about 1920. Davis et al. concluded the recent acidification was due to atmospheric deposition.

Kittredge (1996) sampled seven lakes and their surrounding watersheds in Acadia NP in 1994. The lakes are on Cadillac granite, which is fluoride poor. Data were compared to lakes on two other granite types outside the park with higher fluoride concentrations. Of the three granite types, Cadillac granite lakes had the lowest fluoride in surface water, intermediate surface water S04 and N03 concentrations, and the highest chloride and lowest aluminum concentrations. Soil pH was intermediate in lakes on Cadillac granite, but had the highest base saturation. Kittredge found that lake water fluoride concentrations reflected fluoride concentrations in bedrock, resulting in strong differences in average lake concentrations. Precipitation chemistry substantially affected average chloride and S04 concentrations in lake water. Kittredge determined fluoride concentrations in soil were dependent on soil texture, and that coarse soil held little fluoride. Both fluoride and organic carbon can complex with aluminum, increasing the aluminum concentration in lake waters. However, complexation also decreases aluminum toxicity to aquatic organisms, with aluminum-organic carbon complexes having a more beneficial effect than aluminum-fluoride complexes. Therefore, measuring total dissolved aluminum may overestimate the potential for aluminum toxicity. Kittredge modeled the effects of pH, fluoride concentration and organic carbon concentration on aluminum mobility. She reported that at circumneutral pH and low fluoride concentration, lake aluminum was dominated by aluminum-organic carbon complexes. At higher fluoride concentrations, aluminum-fluoride

30 complexes dominated. Decreasing the pH increased the percent of aluminum-fluoride complexes in the lakes.

Kahl (1999) reported on the status of Maine lakes after 1995 implementation of the S02 reductions mandated by the 1990 amendments to the Clean Air Act. He found S04 concentrations in sensitive Maine lakes had declined by 12 to 22 percent since 1982; however, there was not a concurrent decrease in lake acidity. Kahl reported a decline in base cation concentrations (e.g., Ca and Mg) as the reason for the lack of recovery. The base cation decline had been observed over the entire northeastern u.s. According to Kahl, potential causes for the decline included continued high atmospheric deposition ofN, a lag time in response, or the inter­ related influence of climate and acidic deposition on watershed response. .

In 2000, Ballenger and Chalmers (2000) collected UV and habitat data in wetlands of Acadia NP and five other national parks. The objective of the study was to try to relate their data to amphibian survey data collected at the same wetlands. At 30 wetlands on Mount Desert Island, UV measurements, water quality (i.e., pH, specific conductance, alkalinity and apparent color), and habitat characterization data were collected during the breeding season and larval period of pond-dwelling amphibians. Initial water quality data showed some pH values below 5.0 and many ANC values below 100 J.leq/l. The final project report is not yet available.

Breen et al. (2002) provided a summary of data collected between 1998 and 2001 through the park's long-term water chemistry monitoring program. The objectives of the Acadia NP freshwater monitoring program are to characterize baseline water quality conditions, track trends, and detect early warning of anthropogenic impacts. The core program involves annual sampling of 10 lakes that represent a range of geophysical and ecological conditions. Lakes are sampled in spring, summer and fall. Five lakes (Jordan Pond, Bubble Pond, Sargent Mountain Pond, the Bowl and Witch Hole Pond) are sampled to evaluate long-term acidification status. The second set of lakes (Witch Hole Pond, Upper Hadlock, Seal Cove, Echo Lake and Jordan Pond) is sampled for cultural eutrophication. In addition, Eagle Pond, Long Pond and Bubble Pond are sampled at least once a month, May through October, for temperature and transparency. Monitored parameters and monitoring protocols are based on recommendations from a 1997 workshop of subject matter experts. 1998 through 2001 data from the five acidification sampling lakes indicated pH and ANC were relatively stable, seasonally and annually, within each lake. Sargent Mountain Lake had the lowest pH and ANC values, 4.9 and -12.6 J.leq/l, respectively. In the five lakes sampled for cultural eutrophication, annual and seasonal variation of total phosphorus, total Nand chlorophyll-a remained relatively stable, with concentrations within the historical range of variability for these lakes. Total N ranged from a mean low of 0.136 milligrams per liter (mgll) in Jordan Pond to 0.451 mgll in Witch Hole Pond. As part of the freshwater monitoring program, benthic invertebrates are collected in several streams throughout the park. The benthos are analyzed for community composition to provide an indication of water quality.

Nielsen (2002a) estimated dilution of nutrients from domestic septic systems overlying the bedrock units in several watersheds in rural Bar Harbor. She reported that in populated watersheds, the estimated average N03-N concentrations in groundwater ranged from 0.3 mgll to 11.0 mgll. Based on the estimates, Nielsen concluded the aquatic limit for total nitrogen

31 established by the EPA for the protection of high quality streams and lakes, 0.38 mg/l, would be exceeded in most of the recharge scenarios when the groundwater in the bedrock aquifer discharged to surface water.

Nielsen (2003) is classifying park wetlands according to their hydrologic function and degree of susceptibility to degradation from groundwater influences. She is also developing an island­ wide groundwater flow model. This model will show where contaminants that enter the groundwater system are likely to flow. The project will be completed in 2005.

EstuarinelMarine Doering et al. (1995) initiated a study in Bass Harbor Marsh estuary, Acadia NP, in response to qualitative observations that macroalgae biomass had increased and recreational fishery had decreased over the past decade. The objectives of the study were to quantify major sources of nutrients and their fate, predict distribution of nutrients in the system given various management scenarios and characterize the estuary ecology. Doering et al. conducted water quality surveys from 1990 through 1992. They calculated nutrient loading (from freshwater and ocean sources only, not atmospheric deposition) and the distribution of nutrients within the estuary, and developed a model to evaluate the behavior of nutrients in the system. The model indicated the estuary could tend toward eutrophied conditions.

Nielsen (2002b) calculated the N input loads for Northeast Creek, the largest estuarine wetland on Mount Desert Island, from 1999 through 2000. She calculated atmospheric inputs based on NADPINTN wet deposition data (note: she did not include contributions from dry or occult deposition). Nielsen concluded atmospheric inputs represented 1 percent of the total N load to Northeast Creek and less than 10 percent of the total inorganic N load.

From 2000 to 2002, Culbertson et al. (2001) conducted the hydrologic component of a study identifying sources and quantifying inputs of nutrients to Northeast Creek estuary. Nutrient inputs from groundwater, surface water, atmospheric and tidal sources were measured on a combination of monthly and biweekly sampling schedules. Atmospheric inputs were based on NADPINTN data. The final report is pending.

Neckles et al. (Undated) conducted the biological component of the Northeast Creek estuary study from 2000 to 2002. They used stable S and carbon isotopes to determine the impact of nutrient enrichment on estuarine food webs. The experiments were conducted in mesocosms, with different amounts of added N and phosphorus (i.e., ambient, low, medium, and high) and four unenclosed control sites. Neckles et al. measured the response of primary producers, e.g., phytoplankton, macroalgae and epiphytes, to nutrient enrichment. Dominant primary producers and consumers from each mesocosm were sampled for stable isotope analysis. The final report is pending.

Lent et al. (Undated) studied 13 small watersheds on Mount Desert Island from 1999 to 2000 to determine nutrient delivery to coastal waters around the island, and also to determine whether the 1947 wildfire was affecting nutrient delivery in burned watersheds. They calculated nutrient export (N03-N, total N, total phosphorus) for each basin during the study period. Lent et al. found that basins entirely within Acadia NP (lacking human land-based nutrient sources)

32 . ~l exported significantly less total N and total phosphorus than basins that were partly or entirely outside the park boundary. They found no relationship between burn history and nutrient export. Lent et al. further found that N03 export was not significantly different in the two groups of basins, and they concluded N03 export could be similar because atmospheric deposition was the dominant source ofN03 in the study area. A final report is pending.

Culbertson (Undated) is assessing groundwater nutrient inputs associated with urban development and identifying groundwater discharge zones in Bass Harbor and Northeast Creek estuaries. Water samples will be analyzed for domestic wastewater compounds as indicators of urban non-point source contaminants. Results for the two estuaries will be interpreted in terms of current land use activities in the watersheds to evaluate the impact of development on groundwater quality. Monthly water sample collection began in late 2003; the project will be completed in 2005.

Norton et al. (2004) propose to examine the relationship between phosphorus and acidification in oligotrophic surface waters. They hypothesize that the mobility and bioavailability of phosphorus in oligotrophic watersheds that yield low alkalinity surface waters are controlled predominantly by aluminum-hydrogen ion geochemistry in soil, soil water, surface water, and stream and lake sediments. Study sites will include the Hadlock and Cadillac Brook watersheds in Acadia NP. One component of the project, if approved, will involve one-time stream acidification experiments involving addition of hydrochloric acid to assess the capacity of streams to buffer aluminum and phosphorus during changing pH events. The study will begin in 2004.

Previous Recommendations and Unfunded Proposals Kahl (1999) recommended studies to investigate the cause of the lack of recovery of ANC in Maine lakes in spite of decreased S04 deposition. His recommendations included: • obtain a better understanding of the cause and effect between base cations and S04 in watersheds, • study the effects of climate change on variability in surface water chemistry, • improve understanding of the role ofN in acidification, and • investigate the role of dissolved organic carbon in acidification.

A recent report by Stoddard et al. (2002) included Kahl's assessment of Maine surface waters following the 1995 implementation of reductions in S02 emissions. The authors described 1990 through 2000 trends in wet deposition and surface water chemistry in New England, the Adirondack Mountains, the Northern Appalachian Plateau, the Ridge and Blue Ridge provinces of Virginia, and the Upper Midwest. Stoddard et al. stressed the importance of continuing wet deposition monitoring, as well as long-term monitoring of sensitive surface waters, at key sites. The authors suggested the key sites could be used to investigate projects related to: • soil and surface water recovery from acidification, • controls on N retention, • mechanisms of base cation depletion, • forest health, • sinks for S in watersheds, • changes in dissolved organic carbon and speciation of aluminum, and

33 • climate change.

Kahl et al. (2000) prepared a water resources management plan for Acadia NP. The report is intended to guide water resource protection and research in the park through 2005 or 2010. Kahl et al. described the hydrological environment of Acadia NP with summaries of precipitation and fog chemistry, atmospheric deposition, geology, soil characteristics, watershed characteristics, vegetation and fire history, lake and stream chemistry, groundwater, wetlands, marine resources, aquatic and riparian resources and habitats, and threats to water resources. They also recommended management actions related to atmospheric deposition and surface water impacts. These recommendations included: • initiate monitoring of zooplankton communities, • sample soils and sediments to develop the deposition history and concentrations of metals and inorganic toxins of atmospheric origin, • conduct an aquatic ecosystem inventory to assess the present condition and distribution of fish, amphibian and invertebrate species in selected waters, and • design and implement an integrated long-term monitoring program for representative estuarine and intertidal environments in and near the park.

Huntington et al. (2003) are proposing to determine the denitrification potential of tidal wetlands at Northeast Creek estuary on Mount Desert Island, and compare it to an urban-impacted estuary, Bass Harbor. They would measure in situ denitrification rates and associated sediment chemical properties during summer and fall in selected groundwater input locations in the Northeast Creek estuary, establish experimental sediment nutrient enrichment treatments in in situ sediment enclosures and measure denitrification rates and sediment properties over the enclosures, quantify the environmental factors that affect denitrification potential, and estimate the rate of inorganic N loading that can be filtered in shallow groundwater discharge zones in the Northeast Creek estuary. This project has not been funded.

Deposition Summary Pollutant deposition has been monitored at Acadia NP since 1981. There has been a significant decrease in deposition of S04, and also of buffering ions. Trend data for N deposition are not straightforward. Depending on the time frame and pollutants evaluated, N deposition at the park has either increased slightly or shown no apparent trend. Limited data collection indicates cloudwater is more acidic than rainwater at Acadia NP. Recent studies are investigating the utility of using models to improve the accuracy of data collected through tradition deposition monitoring techniques.

A series of studies provided mixed results regarding the effect of atmospheric deposition on park lichens. While two researchers concluded that deposition was not affecting lichens, one research group determined that lichen health and species density were being affected by atmospheric deposition. Similar conflicting conclusions were reached by scientists evaluating the effects of atmospheric deposition and ozone on coastal red spruce foliage and growth. PrimeNet, an intensive ecological research program, evaluated biogeochemical differences between a burned and an unburned watershed at Acadia NP. Researchers concluded that forest type and fire history strongly influenced watershed storage and cycling ofN and other ions.

34 A number of lake and stream chemistry sampling efforts have taken place in and near the park. Data indicate park lakes were naturally poorly buffered, but that buffering capacity in regional lakes has further decreased due to atmospheric deposition. Some lakes and streams in Acadia NP experience episodic acidification. In spite of reductions in S04 deposition, lake ANC values have not substantially increased. Researchers speculate the lack of recovery is due to decreased deposition of buffering ions, e.g., Ca and Mg. In 1998, park staff initiated a long-term water chemistry monitoring program to establish baselines and detect trends in acidification and cultural eutrophication of park lakes. Prior to the late 1990s, little emphasis was placed on investigating the effect of atmospheric deposition on park estuaries. Recent studies have focused on the likelihood of eutrophication of the large estuaries of Mount Desert Island. Most of the researchers have yet to produce final reports; however, preliminary results indicate conflicting opinions about the importance of atmospheric N deposition to estuary eutrophication.

Final project recommendations and unfunded proposals relative to atmospheric deposition at Acadia NP emphasize further investigation of the role of base cations and soil N retention in surface water acidification and recovery in the park. There are also recommendations to expand the long-term monitoring program to include routine sampling of soils, sediments, biota and concentrations of heavy metals and toxic pollutants.

AIR TOXICS Air Toxics Ambient Monitoring A Photochemical Assessment Monitoring Station (PAMS) was established on Cadillac Mountain (elevation of 1530 feet (466 m» in 1997 to monitor downwind impacts from the Boston ozone nonattainment area. The site includes an ozone monitor, a low-level NOx monitor, speciated VOC, and meteorology. Fifty-four VOC hydrocarbons are monitored at Cadillac Mountain, the majority of which are associated with mobile source emissions. Hourly samples are collected May 1 through September 30. Median and maximum I-hour concentrations of the top ten monitored VOC at Cadillac Mountain from 1997 to 2000 (Table 5) were lower than the concentrations monitored at the other two P AMS sites in Maine, Cape Elizabeth and Kittery. Concentrations of all VOC species at Cadillac Mountain were relatively low, and showed no overall trend during the short period of record.

35 Table 5. Top ten VOC monitored at Acadia NP, 1997-2000 (in parts per billion) 1997 1998 1999 2000 Median Max Median Max Median Max Median Max Ethane 1.54 5.38 2.47 7.34 1.89 5.19 1.95 6.92 Propane 1.01 15.27 0.92 17.65 0.81 5.58 0.84 5.42 Benzene 0.87 2.51 1.77 3.52 1.86 3.86 0.55 1.64 Isoprene 0.69 9.72 -- 0.43 10.45 - - Trans-2-Butene 0.58 0.95 0.65 1.25 0.68 1.27 0.27 0.54 Isopentane 0.54 2.99 1.21 4.18 0.69 6.21 0.47 3.66 Toluene 0.46 3.52 0.46 5.09 0.41 2.98 0.35 3.56 1,2,3- Trimethylbenzene 0.43 3.57 0.38 2.59 -- 0.24 2.94 n-Pentane 0.41 2.14 ------p-Ethyltoluene 0.37 1.35 0.41 2.84 - - 0.29 1.8 n-Butane - - 0.33 3.67 0.32 8.41 0.26 2.53 2,2,4- Trimethylbenzene - - - - 0.29 1.07 - - 1,2,4- Trimethylbenzene - - 0.52 1.6 0.69 4.69 0.98 3.04

The MDEP performed air toxics modeling analyses in the mid-1990s to estimate ambient concentrations throughout the state. According to the MDEP, these analyses would not be helpful in identifying pollutants of concern for Acadia NP because 1) the models were run using only point source emissions, and 2) results were reported on a broad-scale, countywide, basis (R. Greves, pers. comm., 2003). The MDEP has formed a stakeholder group to address air toxics monitoring and regulatory considerations in the state. Ideally, the air toxics program would consider area and mobile sources, in addition to point sources. As a result of the stakeholder process, new air toxics monitoring may be initiated in some locations in Maine in the future.

From 1998 through 2000, Golomb et al. (2001) measured wet and dry deposition of 16 polycyclic aromatic hydrocarbon (P AH) species at a site near Boston and a rural site in Casco Bay, Maine, 95 miles (150 km) southwest of Acadia NP. They found that while PAH wet deposition was comparable at the two sites, dry deposition was an order of magnitude higher at the Boston site. Golomb et al. attributed the P AH wet deposition to regional sources and the dry deposition to local sources. Source apportionment modeling indicated major source categories contributing to dry deposition of PAH at Casco Bay were jet aircraft, gasoline-fueled vehicles, diesel-fueled vehicles and wood combustion.

Mercury Deposition Monitoring The objective of the Mercury Deposition Network (MDN) is to develop a national database of weekly concentrations of total mercury in precipitation and the seasonal and annual flux of total mercury in wet deposition. The data will be used to develop information on spatial and seasonal trends in mercury deposited to surface waters, forested watersheds, and other sensitive receptors. The MDN began a transition network of 13 sites in 1995. Beginning in 1996, MDN became an official network in NADPINTN with 26 sites in operation. Over 50 sites were in operation during 2000. The network uses standardized methods for collection and analyses.

36 A MDN monitor was installed at McFarland Hill in 1995 (site ME98, elevation of 499 feet (152 m». Summarized annual concentration data, in nanograms per liter (ng/l), and deposition data, 2 in micrograms per square meter (J.Lg/m ), are available for 1996 through 2003 (Table 6). More information about the MDN program, and all 1995 through 2004 data for the park, are available at (http://nadp.sws.uiuc.edu/mdnl). MDN data for 2003 indicate deposition at Acadia NP was comparable to deposition at other sites in New England and the western Great Lakes, lower than at sites in the Midwest and southeast U.S., and higher than at sites in the western U.S. (Figure 26). 2003 concentration values were low to moderate across the Mid-Atlantic and Northeast U.S., with higher values in the Southeast, Midwest and Great Lakes, and at a number oflocations in the western U.S. (Figure 27).

Ta bl e 6 . W et mercury d eposl'f Ion an d average wet concentratIOn at A cad' la NP YEAR DEPOSITION (p.tg/mz) CONCENTRATION (ngffl 1996 7.3 7.4 1997 7.0 9.7 1998 9.0 6.1 1999 8.0 6.1 2000 8.7 7.0 2001 5.3 8.0 2002 8.0 5.1 2003 7.2 5.8

Other mercury parameters have been monitored at the park on a short-term basis. Event-based mercury wet deposition monitoring was conducted in 1997 and 1998 to help track mercury transport by individual air masses and, thereby, aid source identification. Continuous vapor­ phase mercury monitoring was conducted at Acadia NP and three locations in Nova Scotia, Canada, in 1996 and 1997. Results are not available for either monitoring effort. Mercury Deposition Network samples from Acadia NP were evaluated for methylmercury concentration from July 2000 to July 2001. The results indicated that the majority of the mercury was deposited in elemental form, with a negligible percentage deposited as methylmercury. i VanArsdale et al. (Undated) compared and contrasted mercury deposition at a number of New England sites in 1997 and 1998. They reported the Acadia NP MDN site showed no clear seasonal patterns of deposition, unlike a site in Vermont. In 1997, Acadia NP frequently had elevated mercury concentrations in precipitation events. VanArsdale et al. reported significant year-to-year variation in deposition at the sites. They reported that coastal sites appeared to receive more mercury deposition than inland sites. The Acadia NP data suggested that mercury concentration may not co-vary with weekly S04 and N03 concentrations at the adjacent NADPINTN monitor. However, the same was not true for all ofthe New England sites.

Nelson et al. (2003) examined seasonal patterns of MDN data collected at Acadia NP, Trout Lake, Wisconsin, and Congaree Swamp, South Carolina, from 2000 through 2002. For all sites, mercury concentration in precipitation was highest in the winter. At Acadia NP, mercury deposition was highest in the spring, which was consistent with precipitation patterns. The data indicated a possible wintertime contribution of marine-derived mercury to the park from storms that originated over the Atlantic Ocean.

37 Total MercufY Wet Deposition, 2003

Figure 26. 2003 nationwide MDN annual mercury wet deposition (from http://nadp .sws. uiuc. edu/mdnl)

'Total~ Mercury Conoentration, 2003

Figure 27. 2003 nationwide MDN annual average mercury wet concentration (from http://nadp.sws.uiuc.edu/mdn/)

38 In 2003, Fitzgerald and Engstrom (2001) co-located a 2lOPb deposition sampler with the MDN monitors at Acadia Np· and seven other sites in the western, mid-continental, eastern and southern U.S. They propose to use the mercury:2lOPb relationship in precipitation samples collected at the sites to examine the apportionment of mercury sources (global versus regionaVlocal) in atmospheric mercury deposition for distinct and significant geographic and demographic regions. Sampling will be conducted over a 12-14 month period. Results should be available in 2006.

Air Toxics Deposition Modeling Kahl et al. (2002) initiated a project in 2003 to develop a predictive park-scale contaminant deposition map for the park. The eventual goal is to develop a model based on throughfall deposition that can predict inputs to the watershed, with predictions for regions and watersheds at greatest risk from high loading of specific contaminants. Kahl et al. will map S deposition on the watershed scale using the Weathers et al. model (discussed above), then compare the watershed-scale deposition map to the map created by Weathers et al. for the entire park. They will investigate how hotspots and interpolations correspond between the two maps and will adjust the small-scale map, as necessary, to compensate for the effect of scale. Kahl et al. will then apply the model to mercury and 15 other analytes, including NH4, aluminum and methylmercury. The project will be completed in 2005.

Air Toxics Effects The Northeast Ecosystem Research Cooperative (NERC) Mercury Research Group has initiated a project to document the extent of mercury distribution in northeast North American surface waters, sediments and key biota and to relate that distribution to depositional gradients, land cover, topography and land use (Northeast Ecosystem Research Cooperative 2003). The NERC Mercury Research Group is composed of scientists from 17 different U.S. and Canadian universities, nonprofit groups, and federal and state agencies. NERC project members are gathering and synthesizing existing databases related to mercury deposition, concentration, and effects. Data analysis will involve preparation of isopleth maps of mercury distribution in water, sediments, fish and piscivorous birds. Researchers will then analyze the relationship between mercury exposure and availability patterns that are influenced by hydrological, biological and geochemical factors. The project reports are slated to be published as a special edition of the journal Ecotoxicology in 2005.

Terrestrial Norton et al. (1997) collected hummock cores from Big Heath Pond and a sediment core from Sargent Mountain Pond in 1983. The cores were analyzed for mercury and lead accumulation rates. The cores showed increased accumulation of mercury starting in the late 1800s and peaking about 1970. Norton et al. reported the rates declined sharply from 1970 to 1982.

Webber (1996) collected one-week samples of through fall under spruce and beech (Fagus spp.) canopies in October through November 1995 and compared mercury concentrations in throughfall to concentrations in open field precipitation samples. She found the highest mercury concentrations under spruce canopy, intermediate concentrations under beech canopy, and the lowest concentrations in open field precipitation (note: she only had 2 valid sample periods).

39 Amirbahman et al. (in review) evaluated the effects of fire on mercury availability in watersheds. The previously-burned Cadillac Brook watershed has thin soils and predominantly deciduous vegetation; the unburned Hadlock Brook watershed has thick soils and predominantly coniferous vegetation. Soil samples were collected in 1999. Amirbahman et al. found total mercury concentrations were higher in Hadlock Brook soils than in Cadillac Brook soils. Soil pH was higher in Cadillac Brook. They conducted adsorption experiments to study the interaction between mercury and 0 horizon soil material and concluded dissolved mercury concentrations in the 0 horizon were controlled by dissolved organic carbon concentrations. Amirbahman et al. found higher methylmercury concentrations in soils at Cadillac Brook. They determined methylmercury concentrations were not a function of the total mercury pool in the watershed. Amirbahman et al. concluded landscape variables such as soil pH, vegetation type, and land use history may be determining factors for the susceptibility of biota to high mercury concentrations.

Johnson (2002) collected precipitation, litterfall and streamwater samples in 1999 and 2000 from Cadillac Brook and Hadlock Brook to determine which landscape factors affected mercury deposition and export. He found that watershed sites which face south to southwest received the highest mercury deposition. Sites with softwood vegetation also received higher mercury deposition than other vegetation types. Johnson concluded the difference was due to the higher scavenging efficiency of the softwood canopy structure. Methylmercury deposition was not affected by these factors. Mercury deposition was lower in the Cadillac Brook watershed than in Hadlock Brook because post-fire regeneration was dominated by mixed hardwoods whereas softwoods dominated the landscape in Hadlock Brook. Johnson theorized fire likely volatilized mercury in organic matter at Cadillac Brook, resulting in Cadillac Brook exporting less mercury than Hadlock Brook. Hadlock Brook, however, exported more methylmercury. Johnson performed a budget calculation which showed that 95 percent of total mercury deposited on the Cadillac Brook watershed was retained, while 87 percent of deposited mercury was retained on the Hadlock Brook watershed. Twenty-five percent of methylmercury deposited on the Cadillac Brook watershed was retained, while 39 percent was retained by the Hadlock Brook watershed. Litterfall was found to be a major mercury pathway to the forest floor. Johnson concluded methylmercury export appeared to be controlled by soil processes in the riparian zone, rendering methylmercury budget an inaccurate portrayal of methylmercury dynamics in these watersheds. He further concluded site aspect and differing vegetation type were the most influential factors affecting mercury deposition to the watersheds.

Nelson (2003) is refining hydrologic and chemical input estimates at the Cadillac Brook and Hadlock Brook watersheds. The project will better quantify winter and summer inputs of water to the forested watersheds, and will quantify the non-growing season atmospheric deposition of mercury and major ions, components of the whole-watershed study that have not yet been investigated. Nelson proposes to 1) calculate reduction of precipitation volume under different types of canopies as compared to wet-only data during the growing season, 2) determine interception-sublimation loss during winter, and 3) analyze snow solutions for mercury and major ions to quantify winter deposition. She is using a Li-Cor Plant Canopy Analyzer to assess canopy coverage at 84 existing throughfall sites in the park in the winter, using GIS and statistical methods to develop a vegetation-weighted water input estimate for the paired watersheds, collecting snow from at least five selected sites in each of the watersheds after large

40 snow events and analyzing the -snow solutions for mercury and major ions. Sampling began in the winter of 2003-2004, and the project will be completed in 2006.

Norton et al. (2002) initiated a project in 2003 to assess elements and pollutants in organic and inorganic soil, peat and lake sediments. Pollutants include copper, cadmium, chromium, mercury, nickel, lead, vanadium, zinc and organic constituents such as dioxin species, furans, polychlorinated biphenyls (PCB), organochlorine pesticides, and P AH. The objectives of the study are to 1) determine the history of deposition of contaminant metals and organic compounds to the Acadia NP landscape, 2) determine the degree of contamination in the park, relative to background, 3) assess the storage of these contaminants in sediments, bogs, and soils, and 4) identify those contaminants that should be the focus of future research. They propose to assess atmospheric deposition of contaminants at low-elevation non-forested and forested sites and high elevation sites.

Freshwater Peckenham et al. (2001) conducted sampling in the fall of 2002, and in: spring and summer of 2003, to establish baseline water quality data with respect to vehicle emissions and other pollutants (e.g., oil spills and tire tread) in streams along park roads. Perennial springs located away from roads are being used as control sites. Pollutants include VOC in fuel, heavy hydrocarbons like oil and grease, complex organic compounds from tires, and toxic metals from tires and brakes. A project report is not yet available.

EstuarinelMarine The National Oceanic and Atmospheric Administration (NOAA; National Oceanic and Atmospheric Administration 1988) sampled sediments at 212 coastal and estuarine sites throughout the U.S. in 1984 through 1987 as part of the National Status and Trends Program. Sites in coastal Maine included Sears Island, Pickering Island, Frenchman Bay and Penobscot Bay. NOAA researchers measured total pesticides, total dichlorodiphenyltrichloroethane (DDT), total PCB, total PAH, total organic carbon, antimony, arsenic, cadmium, chromium, copper, lead, mercury, nickel, selenium, silver, tin and zinc. Sediment characteristics such as grain size, which affect contaminant concentrations, were also quantified. With few exceptions, the higher levels of contamination were found among the 175 sites where the sediment was muddy rather than sandy. Sites were ranked according to concentration levels for each pollutant. Measurable concentrations of pollutants were found in all samples from Maine, but concentrations were generally low. Pickering Island, however, ranked in the upper 20 sites for total PAH concentration.

In 2000, EPA initiated the multi-year National Coastal Assessment (NCA) to determine the condition of the Nation's estuarine waters (C. Strobel, pers. comm., 2003). The goal is to determine the condition of all of the Nation's estuarine waters using a common probabilistic design and uniform set of indicators. Since 2000, approximately 35 stations have been sampled per year in the state of Maine for sediment contamination, toxicity, benthic community condition and contaminants in lobster tissue. The probabilistic design employed is flexible enough to allow for an increased sample density in areas of concern. At the request of the MDEP, NCA sampling density was increased in the estuarine waters surrounding Acadia NP (Frenchman and

41 Blue Hill Bays). EPA is working with the NPS to incorporate the sample design into a standardized estuarine monitoring program for the agency. A project report is not yet available.

Chen and cooperators initiated a project in 2003 to examine the bioaccumulation and trophic transfer of inorganic and methylmercury in estuarine food webs, focusing on the benthic, epibenthic and nektonic species in the intertidal and subtidal portions of estuaries (C. Chen, pers. comm.,2003). They are comparing the food webs of three Gulf of Maine estuaries that differ in hydrology and contaminant and nutrient loads. The study sites are Great Bay, New Hampshire, a highly industrialized estuary; Wells Estuary, Maine, which is impacted by commercial and recreational development, but not industry; and Salisbury Cove, Mount Desert Island, the least affected site. Chen et al. are measuring trace metal bioaccumulation in multiple trophic levels in water and sediments and relating the metal concentrations to trophic positions of intertidal and subtidal nekton species.

King et al. (Undated) have been funded to collect sediment cores from two sites in Somes Sound in Acadia NP to reconstruct the history of contaminant, nutrient, and vegetation inputs to the system. They will analyze for trace metals, nutrients, and organic contaminants.

Wildlife As part of the EPA Environmental Monitoring and Assessment Program (EMAP), Stafford and Haines (1997) collected fish from 120 randomly selected lakes in Maine (including Hodgdon and Bubble Ponds in Acadia NP) and evaluated tissue mercury concentrations. The highest concentrations were found in large and long-lived nonsalmonid species. Chain pickerel (Esox niger), smallmouth bass (Micropterus dolomien), largemouth bass (Micropterus salmoides), and white perch (Morone americana) had the highest average mercury concentrations. Stafford and Haines found mercury concentration increased with the age and size of the fish.

Haines (2001 ?) characterized mercury contaminated fish and their distribution in Acadia NP and assessed the environmental factors that were related to mercury accumulation by aquatic organisms. He collected and analyzed water and fish samples from 10 lakes on Mount Desert Island and Isle au Haut. Water quality parameters measured included ANC, specific conductance, true color, Ca, Mg, potassium, sodium, S04, N03, chlorine, dissolved organic carbon, and N~. Haines found smallmouth bass, chain pickerel, and white perch had the highest mercury levels while brook trout, lake trout, and landlocked Atlantic salmon (Salmo salar) had the lowest concentrations. All samples exceeded the U.S. Food and Drug Administration human fish consumption advisory level of 1.0 part per million (ppm) wet weight. A few large warmwater fish collected in Acadia NP had among the highest mercury concentrations, on a per-weight basis, reported anywhere in the U.S. Due to the small sample size and similarity of lakes, Haines was not able to relate fish mercury concentration to lake physical or chemical factors. All but one of the lakes had pH values above 6.0 and ANC values below 100 J.leq/l. Haines also conducted a mercury food chain study in Hodgdon and Seal Cove Ponds. The ponds are in the same drainage, but fish mercury concentrations have been found to be higher in Hodgdon Pond. Haines concluded the differences in fish mercury concentrations were due to food chain uptake and biomagnification of mercury. In order to determine trends in mercury deposition, sediment cores from Hodgdon Pond and Sargent Mountain Pond were analyzed for mercury. At Sargent Mountain Pond, mercury accumulation was low and constant

42 until about 1900, followed by an increase through 1970, then a slight decline. In Hodgdon Pond, the mercury accumulation was much lower. Haines concluded the mercury in the sediment cores taken from Sargent Mountain and Hodgdon Ponds was from anthropogenic sources.

Also as part ofEMAP, Mower et al. (1997) collected fish, water and sediment samples from 125 Maine lakes in 1993 and 1994 (including Bubble and Hodgdon Ponds in Acadia NP). The goal was to determine the distribution of contaminants in fish from Maine waters. Mercury was detected in 99 percent of samples. Lead and cadmium were also detected in a large number of samples. Predatory species had higher mercury concentrations than omnivorous species, and warmwater species had higher mercury concentrations than coldwater species. Higher concentrations of lead and cadmium were found in warmwater than in coldwater species; DDT and PCB concentrations were higher in coldwater species. Concentrations of cadmium, DDT, PCB and chlordane exceeded human fish consumption advisory levels in some fish. Fish species, fish age and length, lake color, and lake water S04 concentration were correlated with mercury concentrations in fish. Mower et al. found no significant correlation between fish mercury concentrations and water pH or between fish mercury concentrations and mercury concentrations in sediments.

In 1995, Burgess (1997) evaluated mercury concentrations in five fish species from 10 lakes on Mount Desert Island. He also performed a comparative food chain mercury study in Hodgdon Pond and adjacent Seal Cove Pond. Smallmouth bass from Seal Cove Pond had been found to have lower mercury concentrations than those from Hodgdon Pond. Water, sediment, plankton, macroinvertebrates and prey fish species were collected seasonally from both ponds and analyzed for total and methylmercury. The ponds had similar pH values. Burgess concluded that in Hodgdon Pond, warmer, low-dissolved oxygen hypolimnetic water was probably contributing to enhanced bioavailability of mercury, as seen by higher methylmercury concentration in plankton (note: his conclusion was based on three samples). He found Hodgdon Pond also had an extra trophic link, i.e., larval fish and isopods in the diet of yellow perch, which could contribute to increased bioaccumulation in prey species. Burgess acknowledged that differences in watershed size could also influence mercury levels, and that he did not evaluate that factor.

Webber and Haines (2003) studied the effects of methylmercury on predator avoidance behavior in golden shiners (Notemigonus crysoleucas). They collected adult golden shiners, a common prey fish, from a pond in Brewer, Maine, in 1996. Methylmercuric chloride solution was added to the fish base diet and the shiners were fed control, low or high mercury diets. After 90 days, fish were measured and anti-predator response was tested. Webber and Haines found no significant difference in growth between fish on control and mercury diets. They also found no significant difference in the activity of the neurotransmitter acetylcholinesterase between treatments. Webber and Haines did find a significant difference in whole body and brain mercury concentrations between treatments. The anti-predator response experiments showed methylmercury elicited hyperactivity and an overreaction to stimuli. Webber and Haines concluded these behaviors could lead to increased predation.

Phillips (1978) studied bald eagles (Haliaeetus leucocephaius) on Mount Desert Island in 1977 in response to reported declines in eagle populations throughout Maine. He found that eagles in

43 the Bar Harbor area are non-migratory, meaning that all contaminants are picked up locally. Phillips reported that DDT was measured in an unhatched eagle egg collected on Mount Desert Island in 1977.

Welch (1994) evaluated differences in contaminant levels and reproductive rates of eagles breeding in different types of habitats in Maine. She collected 132 blood samples and 12 eggs from 30 nest sites in 1991 and 1992. Welch found differences in productivity among habitat types, with eagles nesting on lakes having the lowest productivity, followed by those nesting on rivers, then those nesting on estuaries, and eagles nesting in marine habitats having the highest productivity. Further, she found that productivity of Maine eagles was lower than that reported in other states. PCB and DDT concentrations in eagle nestlings were also higher in Maine than in other areas of the country, and blood mercury levels of eaglets were higher than in most states. Welch reported PCB levels were higher in the 1992 than the 1991 samples; she found no such difference in mercury or DDT levels. There was no difference in contaminant levels between siblings. The highest PCB concentrations in Welch's study were from samples collected on Mount Desert Island, with the highest concentration from a nest at Acadia NP. Welch concluded the differences in contaminant burdens between habitats were due to extreme diet differences between inland and coastal bald eagles. Coastal birds ate mostly other birds, while inland birds ate mostly fish.

The FWS (U.S. Fish and Wildlife Service 1992) evaluated contaminants in Maine bald eagles in 1991. They collected blood, feather and egg samples from 58 nests statewide. The FWS found eaglets from different habitat types did not differ significantly in blood PCB or DDT levels, however, blood and feather mercury levels differed by habitat type along the same pattern observed by Welch (1994) for eagle productivity (i.e., mercury levels highest in lake habitats, lowest in marine habitats). The FWS also found that mercury levels tended to be higher in the northern and southeastern parts of the state and lower in the coastal south-central and southwestern parts of the state. Mercury and PCB levels from the Acadia NP area were consistent with those from other coastal Maine sites (comparative information on DDT concentrations was not provided). The FWS reported that PCB and DDT levels in eagle eggs from Maine had declined since the 1970s and 1980s, but mercury levels had not decreased. The FWS concluded mercury levels of eaglets living near inland lakes and rivers could be high enough to cause behavioral changes in the birds.

Matz (1998) investigated biomagnification, potential point sources and atmospheric deposition as possible causes of high contaminants in bald eagles. The study was conducted in 1994 to 1996 and involved 6 bays on the Maine coast from Penobscot Bay northeast to Machias Bay. She sampled eaglet blood, herring gull (Larus argentatus) eggs, sculpins and mussels for organochlorine pesticides and PCBs and compared concentrations among habitats. Matz found no relationship between mean annual productivity and mean contaminant concentrations in nestlings, even though concentrations were within the range associated with reduced productivity at other locations. She also found no statistically significant relationships between contaminant concentrations and circulating hormone levels, so there was no indication of endocrine disruption. Matz found no significant difference among habitat types in dichlorodiphenyldichloroethylene (DDE) concentrations in eaglet blood, but a significant difference in PCBs. She also reported a significant difference in eaglet blood PCB

44 concentrations between freshwater and saltwater habitats. There was no statistical difference among bays based on eaglet blood samples; however, mussel samples suggested contaminant concentrations in Frenchman Bay and Gouldsboro Bay (next bay north) were different than the other four bays. Maine eaglets had higher levels of DDE and PCBs than those reported for all other studied sites except a highly polluted location on Lake Erie. Matz concluded biomagnification, as assessed by habitat and trophic differences in DDE concentrations, was not evident within the Maine bald eagle population, although there was evidence for biomagnification of total PCBs. She acknowledged, however, that differences in total PCB concentrations among habitats may have been confounded by coastal point sources of PCBs, and that her analysis may also have been limited by low sample size. Nevertheless, her data suggested there may be a significant PCB point source near Frenchman and Gouldsboro Bays, and there may also be a point source of DDT in Frenchman Bay.

Longcore and Haines (1998) compared mercury bioaccumulation in tree swallows (Taehycineta bieolor) at Acadia NP to those at an inland Maine site. In 1997, they collected eggs, nestlings, feathers, and food boli from 5 clutches of tree swallows in the park near wetlands with documented high mercury concentrations. Longcore and Haines found no apparent differences in egg and nestling variables, such as shell thickness and nestling size, between the Acadia NP sites. Mercury concentrations in eggs and feathers were higher at the Acadia NP nests compared to the inland nests. Nevertheless, the Acadia NP nests had high hatching and fledging success. Additional data were collected in subsequent years but have not yet been provided to the park. The final report is pending.

Bank et al. (In press) analyzed mercury concentrations in northern two-lined salamander (Euryeea bislineata) larvae collected from 17 streams at Acadia NP in 2000 and 2001. They found mercury concentrations in larvae were significantly different among streams and that overall variation within streams was low. Mercury concentrations in salamanders were higher than those reported for brook trout (Salvelinus fontinalis) collected from the same stream. Total mercury concentration was not correlated with length or weight of salamanders. Bank et al. determined mercury can bioaccumulate quickly in two-lined salamanders (within 12-24 months). They thought this was due to the fact that the larvae live and forage on invertebrate prey that live at the interface of the water column and streambed sediments where mercury and methylmercury concentrations are high. Bank et al. concluded the salamanders play an important role in mercury bioaccumulation at Acadia NP since the larvae are part of the aquatic food web and the adults are part ofthe terrestrial food web. The final project report is pending.

Bank et al. (2002) compared mercury levels documented in samples of soils, sediments, stream water, fish and salamanders collected during previous studies in Acadia NP to those of newly­ collected samples of selected frog species inhabiting park wetlands. The wetlands include those where frog die-offs have recently been reported. They looked across the landscape from headwaters (inhabited by stream salamanders) to receiving surface waters (inhabited by frogs). Bank et al. quantified concentrations of mercury in sediments, salamanders, and green frog (Rana clamitans), bullfrog (Rana eatesbeiana), or spring peeper (Pseudaeris erieifer) larvae from five sites where die-offs have been reported and compared the data to five sites with no reported frog die-offs. The study was conducted in 2003. A project report is not yet available.

45 Evers et al. (1999) assessed the impacts of methylmercury on loon (Gavia immer) reproduction and behavior. Between 1994 and 1998, they collected 78 abandoned eggs along with blood and feather samples from 140 adult and 54 juvenile loons in Maine. Behavior studies were conducted in 33 loon territories. Evers et al. attempted to correlate mercury concentrations in samples with reproductive success, egg viability, loon behavior, developmental stability, and immunosuppression. Recaptured loons showed increased blood mercury levels in successive samples. Overall productivity had a tendency to decline as adult blood mercury concentrations increased; however, Evers et al. admitted reproductive success could be influenced by other factors they didn't consider. Mercury concentrations did not differ significantly between fertile and non-fertile eggs. The behavioral studies that tried to link mercury concentrations to effects were inconclusive.

In a subsequent report on sampling focused on southern Maine and New Hampshire, Evers et al. (2003) described geographic differences in methylmercury availability. They discussed a west to east trend across North America, with loon blood mercury levels from New England being the highest. Evers et al. stated that within-region differences were primarily related to hydrological and biogeochemical factors. They reported that within-region loon blood mercury levels appeared to be similar in Maine, New Hampshire and New York and tended to be lower in Vermont. Based on 681 loon blood samples collected across New England, New York and Eastern Canada from 1994 through 2002, Evers et al. identified several areas in Maine that have higher than average levels of mercury. Hotspots were located in southern Maine, the western mountains, and a small area near Bangor. Evers et al. described the following key pieces of information that had been obtained from their long-term sampling effort and observations of loon behavior: • loon blood mercury levels were significantly positively correlated with circulating levels of corticosterone, a stress hormone, • there was strong evidence of a negative relatiqnship between mercury levels and foraging behavior and efficiency, • there was a significant relationship between increasing adult blood mercury levels and decreasing reproductive success, • recaptured adult loons exhibited a. significant annual increase of feather mercury concentrations (9 percent in males and 5.6 percent in females), • the overall result was a 40 percent reduction in reproductive success of the Maine loon population. Evers et al. recommended risk categories for loon populations based on mercury concentrations in eggs, blood, feathers, and prey fish. Using the risk categories, estimates of bioconcentration factors and a population model, Evers et al. developed a Maine-based Wildlife Criterion Value (WCV). A WCV estimates wildlife population viability through measurement of contaminant stressors such as surface water mercury levels. The WCV model estimated that an unfiltered total mercury water level less than 1.41 nanogram/liter would be protective of loons and other wildlife at the population level.

Evers and Lane (2000) evaluated the possibility of using belted kingfishers (Ceryle alcyon) as indicators of methylmercury availability in aquatic systems in Maine. They were reasoned to be good indicators because 1) if open water is available, male kingfishers may be year-round residents, and 2) because of the amount of food consumed, methylmercury intake could be as

46 much as three times higher in kingfishers than in bald eagles or osprey (Pandion haliaetus). In 1998 and 1999, Evers and Lane collected blood and feather samples from 38 adult and 106 juvenile kingfishers at four major habitat types: marine (Casco Bay), estuary, riverine, and upper watershed lakes. They also collected prey fish at the birds' burrows. The mean mercury concentrations of samples collected at reservoirs and rivers were higher than those collected in marine and estuary habitats. In addition, mean concentrations were lower in juveniles than in adults. Evers and Lane did not report any attempt to correlate prey fish mercury concentrations to kingfisher mercury levels.

Shriver et al. (2002) evaluated mercury concentrations in blood samples from two sympatric species of sharp-tailed sparrows, Nelson's sparrow (Ammodramus nelsoni subvirgatus) and saltmarsh sparrow (Ammodramus caudacutus caudacutus). They collected blood samples from 28 Nelson's and 54 saltmarsh sparrows during the breeding seasons of 2000 and 2001 in five marshes along the Maine coast. Shriver et al. reported no differences in blood mercury concentrations between sexes, but a 41 percent greater average blood mercury concentration in saltmarsh sparrows than in Nelson's sparrows. They hypothesized the difference could be due to differential prey selection between species. Shriver et al. also reported a difference in average sparrow blood mercury levels between sites.

Evers et al. (2002) evaluated mercury concentrations in mink (Mustela vison) and river otter (Lutra canadensis) in Maine. In 2000 and 2001, they collected 26 river otter and 47 mink carcasses statewide from fur trappers, plus an unknown number of carcasses from Acadia NP. Fur, brain and liver tissues were analyzed for total mercury. Otter fur mercury concentrations ranged from 1.14 ppm at Acadia NP to 32.0 ppm at Munsungan Pond. Otter brain and liver mercury levels were lower than mercury concentrations in fur. Evers et al. found a similar variation in mercury concentrations in mink, with fur having higher levels than brain or liver tissues (values specific to Acadia NP were not reported). They note other research indicates fur mercury levels are not as easy to interpret as blood or tissue concentrations. The highest mercury concentrations were found in carcasses collected in the northwest part of the state.

Previous Recommendations and Unfunded Proposals Haines et al. (2000) assessed contaminant threats at Acadia NP in 1998. They concluded ozone, acid rain, and mercury effects were well studied within the park. Haines et al. stated that the amount of airborne organochlorines reaching the park was not known but was not expected to be significant. Nevertheless, they recommended determining the nature and extent of organochlorine contamination in the park. The majority of the monitoring recommendations related to small-scale contamination associated with sewage effluent, oil spills, or PCB disposal. More generic recommendations related to toxics included the following: • sample organochlorine concentrations in fish-eating birds at Hodgdon, Seal Cove, Long, and Lower Hadlock Ponds, and • sample PCB concentrations in fish, bivalves or annelids at the Hop, Bald Porcupine, Sheep Porcupine, and Bar Island.

Haines (2001?) also recommended evaluating concentrations of mercury III a variety of piscivorous birds and mammals collected in the park.

47 Evers et al. (2003) recommended additional collection of fish and water mercury data, particularly in lakes with low pH and high dissolved organic carbon concentrations, to clarify estimated bioconcentration factors for a WCV for Maine.

Shriver et al. (2002) recommended the following additional work on sharp-tailed sparrows: • determine mercury concentrations for sharp-tailed sparrows collected at other coastal marshes in Maine, • compare mercury concentrations of sharp-tailed sparrows with those of tree swallows breeding in the same marshes, • determine mercury concentrations of the sharp-tailed sparrow prey base, and • measure levels of other contaminants in sharp-tailed sparrows.

As a follow up to the intensive paired watershed study, Kahl et al. (2003) recommended the following: • investigate the flux of mercury in and out of the organic horizon of soils, • measure the gaseous emissions of mercury from soils, and • investigate the role of climate change on changes in mercury bioavailability.

Evers (2003) is proposing to develop an ecological risk assessment strategy, based on loon productivity, which can be used to identify stress thresholds and trigger points for lentic environments. The objectives of the project are to 1) collect and evaluate common lentic environmental parameters to determine the relationship between water quality and the potential threat to biological resources in lentic environments; and 2) develop a national ecological risk assessment strategy for lentic environments in northern national parks using the common loon. The study would be conducted in Acadia, Glacier, Isle Royale, Voyageurs, and Yellowstone NPs. Evers is proposing to use loon productivity as the baseline and to identify trigger points in loon productivity (spatially explicit by park) that would elicit further investigation into identified stressors. The five priority groups of potential stressors are mercury contamination, lake acidification, water clarity, water level regulation, and human use patterns. This proposal has not been funded. Bank and Krabbenhoft (2004) propose to examine mercury concentrations in water, sediments, invertebrates, salamanders, and fish collected from national park streams distributed along a latitudinal gradient from Maine to Tennessee. They propose to address variation in mercury cycling across a gradient of physical, climatic, and biotic conditions in the eastern U.S. by documenting the spatial extent of mercury contamination and comparing patterns of mercury concentrations with watershed conditions. Bank and Krabbenhoft are proposing to collect five larval salamanders and five forage fish in six streams at Acadia NP and at each of the other study sites. Habitat characteristics and water quality variables (PH, conductivity, dissolved organic carbon, dissolved oxygen, N03-N, and phosphorous) would be recorded at each sampling site. Landscape (e.g., land cover, road presence, wetland proximity and type, slope, elevation, and aspect) and microhabitat (e.g., collection site elevation, air and water temperature, location, percent canopy cover, substrate size class, position in stream bed, and water depth) variables would be recorded and correlated separately to salamander mercury levels using stepwise logistic regression or stepwise multiple regression. This proposal has not been funded.

48 Air Toxics Summary Wet mercury deposition has been monitored at Acadia NP since 1995 and ambient concentrations of VOC have been monitored since 1997. No trends are apparent in either dataset. A number of ongoing studies are attempting to clarify past and present spatial and temporal patterns of toxic pollutant deposition in the park.

A great deal of emphasis has been placed on studying and documenting the effects of mercury deposition on resources in the northeast U.S., including those at Acadia NP. The NERC Mercury Research Group is publishing an article in early 2005 that will describe the current state of knowledge regarding mercury deposition and effects in the Northeast. Studies at the paired watersheds in Acadia NP indicate landscape variables, e.g., soil pH, vegetation type, and land use history, may be more important than the amount of mercury deposited in influencing mercury bioaccumulation.

Mercury and other toxic pollutants have been measured in water, sediments and biota in both estuarine and freshwater ecosystems in Maine; however, until recently, not much attention has been paid to toxins in the estuarine systems of Acadia NP. Current projects are examining deposition history, food webs dynamics and concentrations in biota. Mercury concentrations have been measured in a number of freshwater fish species in the park. Results indicate predatory species had higher mercury concentrations than omnivorous species, and warmwater species had higher mercury concentrations than coldwater species. In addition to species type, fish age and length, lake color, and lake water S04 concentration were correlated with mercury concentrations in fish. Elevated DDT, PCB and chlordane concentrations have also been found in Maine fish. Mercury, DDT and/or PCB concentrations have been measured in a number of other species collected in and near the park including mussels, frogs, salamanders, kingfishers, tree and sharp-tailed swallows, gulls, loons, eagles, mink and river otters with some level of pollutant detected in all samples. Attempts to correlate pollutant concentration with impaired reproduction or behavioral abnormalities have provided mixes results.

Final project recommendations relative to toxics encourage evaluating toxic pollutant concentrations in additional wildlife species and studying the landscape factors that may enhance methylation and bioaccumulation.

OZONE Ozone Ambient Monitoring Ozone has been monitored at two permanent sites in Acadia NP: at McFarland Hill from October 1982 to December 1997 (site 230090101, elevation of 400 feet (122 m)) and February 1998 to the present (site 230090103, elevation of 499 feet (152 m)), and at Cadillac Mountain from July 1995 to the present (site 230090102, elevation of 1530 feet (466 m)). A new site was recently installed in the park on the Schoodic Peninsula. Further information on park ozone monitoring is available on the NPS Air Resources Division website (http://www2.nature.nps.gov/air/monitoring/network.htm). Monitoring indicates a couple of exceedances of the I-hour human health-based ozone National Ambient Air Quality Standard (NAAQS) of 0.120 ppm at Cadillac Mountain, and a number of exceedances of the 8-hour ozone NAAQS of 0.85 ppm at both Cadillac Mountain and McFarland Hill (Table 7). Trend analyses show increasing trends in both the I-hour (Figure 28) and 8-hour ozone concentrations at the

49 park between 1992 and 2002. Ozone concentrations at the park are consistent with values recorded at other non-urban monitors in New England (Figure 29). In April 2004, EPA designated the park as non-attainment for the 8-hour ozone NAAQS.

Table 7. Maximum I-hour and 8-hour ozone concentrations at Acadia NP (ppm MCFARLAND HILL CADILLAC MOUNTAIN YEAR I-hour 8-hour I-hour 8-hour 1993 0.094 0.080 N/A N/A 1994 0.092 0.075 N/A N/A 1995 0.119 0.092" 0.134 0.077 1996 0.100 0.073 0.096 0.082 1997 0.099 0.077 0.114 0.085 1998 0.125 0.088 0.123 0.094 1999 0.120 0.092 0.123 0.090 2000 0.080 0.070 0.980 0.078 2001 0.112 0.094 0.117 0.101 2002 0.116 0.089 0.127 0.100 2003 0.097 0.080 0.114 0.083 " Values III bold exceed the NAAQS

Ozone Effects Terrestrial Treshow (1984) established eastern white pine biomonitoring plots in Acadia NP in 1984 to investigate the cause of needle tip necrosis first observed on the pines in 1983. The 20 biomonitoring plots consisted of a total of 300 trees. Treshow reported that injury was evenly distributed throughout the park and that the severity of injury was not associated with environmental or habitat variables.

Sanchini (1986) re-evaluated Treshow's eastern white pine plots in 1985. She examined 294 trees and concluded 91 percent of the trees had ozone injury, although she reported the amount of injury per needle was low. Chlorotic mottle was the most typical type of injury observed.

50 Left Arrow: 1992-2001 Trend Right Arrow: 1993-2002 Trend

• DecreaslrgTrend,p<=O.15 .J DecreaslrgTrerd,p>O.15 t hcreaslngTrend,p<=O.15 ~ tlcreaslrgTrerxt.p>O.15 ...... • NoTrend • hsufficlenl:Oata

Figure 28. Trends in I-hour ozone concentrations at NPS sites (from NPS 2002)

Figure 29. July 1,2001 8-hour peak ozone concentrations in the northeast u.s. (from http://www.epa.gov/airnow/) (green=0-60 ppb, light yellow=61-79 ppb, dark yellow=80-99 ppb, orange= 100-11 0 ppb)

51 Treshow et al. (1986) studied the effects of ozone on radial growth of eastern white pine. In 1984, they evaluated 23 sets of trees, one member of each s~t having foliar injury. and one member of each set without injury. Treshow et al. found no growth trends in either symptomatic or asymptomatic trees. However, they reported a shift in the tree ring indices after 1978, with a decrease in ring width in symptomatic trees. Treshow et al. concluded there was circumstantial evidence that the decreased tree ring width was due to ozone.

Bennett et al. (1986) held a workshop in Acadia NP in 1986 to discuss the possible causes of the observed foliar injury on eastern white pine. The impetus for the workshop was uncertainty about air pollution as the cause of the injury. Workshop participants reached consensus that the necrosis was due either to ozone or semi-mature tissue needle blight (cause of the needle blight was unknown, but air pollution was not suspected). Bennett et al. recommended procedures for distinguishing ozone injury from injury caused by other agents.

Berrang et al. (1986) evaluated the ozone sensitivity of different populations of quaking aspen. They collected 11-14 individuals from five eastern NPS areas, including Acadia NP. The plants were fumigated with ozone in chambers under controlled conditions in 1984 and 1985. Berrang et al. reported that average injury for clones was significantly less for the most polluted park than for the least polluted park, and that there was a high negative association between average injury and ambient ozone levels. Clones from Cuyahoga Valley National Recreation Area showed the least amount of injury, followed by Saratoga National Historical Park, Acadia NP, and Voyageurs NP, with Isle Royale NP clones showing the greatest amount of injury. They concluded natural selection for ozone tolerance in quaking aspen may have occurred in some areas of the eastern U.S.

Foley (1987) evaluated ecosystem disturbance factors that could influence forest development. She established 10 pairs of sites--three pairs on Mount Desert Island and two pairs on Isle au Haut. In each pair, one plot was located on a "good" site (deep soil, moderate slope) and the other plot was located on a "stressed" site (shallow soil, steep slope). Red oak (Quercus rubra), red spruce and white pine were cored to analyze response to climate change, fire and air pollution. Foley found no response that could be linked to air pollution.

Bartholomay et al. (1997) investigated the association between ozone levels recorded in Acadia NP, climatic variables like precipitation and temperature, and white pine radial growth. The project involved 1) creating stand level radial growth models for eight individual stands of white pine, incorporating monthly precipitation, monthly temperature and several measures of ozone exposure from 1983 through 1992; 2) creating a regional radial growth model which combined several white pine tree-ring series from each of the eight stands, utilizing the previously mentioned climate and ozone variables from 1983 through 1992; and 3) describing, at the regional level, the dynamic relationship between white pine radial growth and monthly climate variables (precipitation and temperature) from 1900 through 1992. Bartholomay et al. cored 102 eastern white pine trees in Acadia NP. They found that white pine radial growth was inversely related to ozone level and duration of exposure. Tree-ring chronologies from seven out of eight stands and the regional chronology were all significantly correlated with ozone levels. Regression models suggested ozone had a stronger influence than climate on tree-ring growth. Specifically, short-duration, high-level, ozone events were found to have the greatest negative

52 relationship with tree-ring widths. Tree growth and ozone relationships were found to differ from stand to stand. Bartholomay et al. concluded that site characteristics played an important role in how trees responded to ozone. A regional de-coupling of the growth-climate correlation was not evident in the study. Bartholomay et al. noted that the study was based on correlative data rather than cause-and-effect relationships.

Wenner and Merrill (1998) compared the foliar injury of eastern white pine needles assumed to be due to ozone with the damage to needles affected by semimature-tissue needle blight. The needle blight has been associated with the presence of the fungus Canavirgella barifieldii. In 1993, Wenner and Merrill collected symptomatic and asymptomatic white pine needles from inside ozone fumigation chambers and from outside the chambers at Acadia NP, and from sites in other parts of Maine, Vermont, Pennsylvania and New Hampshire. Damaged and healthy needles were examined under a microscope and compared to needles affected by semimature­ tissue needle blight. Wenner and Merrill concluded that injury observed on damaged needles collected from fumigation chambers was due to the direct stream of air hitting the needles, i.e., it was a chamber effect. They further concluded that early season dieback and blighting of current year needles in natural settings was due to semimature-tissue needle blight, not to ozone, and that ozone damage on eastern white pines was rare.

Kohut et al. (1997) exposed 32 plant species to ozone in controlled chamber studies at Acadia NP. Ozone treatments included charcoal-filtered air (0.5 ambient), ambient concentrations, and 1.5, 2.0 or 3.0 times ambient. Non-chamber ambient treatments were also included. Species injured at ambient levels of ozone were black cherry (Prunus serotina), quaking aspen, white ash (Fraxinus americana), jack pine, big-leaf aster (Aster macrophyllus), and spreading dogbane (Apocynum androsaemifolium). There was some indication that red maple, pin cherry (Prunus pennsylvanica), mountain ash (Sorbus americana), mountain holly (Nemopanthus mucronata), and flat-topped aster (Aster umbel/atus) could also be injured at ambient levels of ozone that occur in Acadia NP. Eastern white pine were not affected by ozone exposures as high as 3.0 times ambient concentrations. Based on the lack of a dose-response relationship at high concentrations under controlled conditions, Kohut et al. concluded ozone was not responsible for the foliar injury observed on eastern white pine in the field. Due to high rates of variability in the data, Kohut et al. were not able to detect significant effects of ozone on photosynthesis. Growth and biomass measurements were not obtained. Kohut et al. recommended that because of their sensitivity to ozone and diagnostic foliar injury symptoms, big-leaf aster, spreading dogbane, quaking aspen, white ash, black cherry and flat-top aster comprise the core of any biomonitoring program designed to assess the incidence and extent of ozone injury at Acadia NP.

Eckert et al. (1999) conducted foliar injury surveys on native vegetation in Acadia NP from 1992 to 1997. Random and nonrandom surveys were conducted in August each year and focused on species and symptoms that had been identified in the controlled fumigation studies conducted by Kohut et al. (1997). Broad-leaf aster and spreading dogbane were sampled every year, while white ash, black cherry, flat-topped aster, small sundrops and bunchberry were sampled less frequently. In 1992 through 1994, either no injury was observed or only a couple of plants were injured. Some injury of broad-leaf aster was observed in 1995 through 1997, and dogbane was injured in 1996. The greatest number of injured plants was reported in 1996, when 22 of 1538

53 ·surveyed broad-leaf aster plants exhibited ozone injury, and 85 of 1424 surveyed dogbane plants exhibited ozone injury. Eckert et al. were not able to develop a simple relationship between ozone concentrations and the number of plants showing injury. They concluded the interactive effect of precipitation and soil moisture influenced ozone uptake. Their theory was supported by the relative lack of ozone injury observed in 1993, 1994 and 1997, which were drought years in the park.

Kohut et al. (2000) developed a field handbook for ozone injury surveys at Acadia NP. The handbook provides background information on ozone and its effects on native plants, as well as recommended methods for conducting field assessments of foliar ozone injury. Use of the recommended methods would allow comparison between future injury assessments and those conducted in 1992 through 1997.

Kohut (R. Kohut, pers. comm., 2004) performed an ozone injury risk assessment for vegetation at Acadia NP using exposure metrics that are more appropriate than the ozone NAAQS for vegetation. He used the park's SUM06 (the running 90-day maximum sum of the 8:00 a.m. to 8:00 p.m. hourly concentrations of ozone equal to or greater than 0.06 ppm) and W126 (a cumulative index of exposure that gives added significance to higher concentrations while retaining and giving less weight to mid and lower concentrations) ozone data, the park's vascular plant list, and the Palmer Z Index, which is used to indicate soil moisture status, to identify ozone-sensitive species (Table 8) and determine the likelihood of injury. Kohut concluded the risk of foliar ozone injury to plants at Acadia NP is high. He reported the levels of ozone exposure consistently create the potential for injury, however dry soil conditions may reduce the likelihood of injury developing in any particular year. The project report will be available in 2004.

a e T ahI e 8 PI ant ~ecles senSItive to ozone a tAca d· la NP

Latin Name Common Name Fami~ Apocynum androsaemifolium Spreading dogbane Apocynaceae Asclepias syriaca Common milkweed Asclepiadaceae Aster acuminatus Whorled aster Asteraceae Aster macrophyllus Big-leaf aster Asteraceae Fraxinus americana White ash Oleaceae Fraxinus pennsylvanica Green ash Oleaceae Parthenocissus quinquefolia Virginia creeper Vitaceae Pinus banksiana Jack pine Pinaceae Pinus rigida Pitch pine Pinaceae Populus tremuloides Quaking aspen Salicaceae Prunus serotina Black cherry Rosaceae Robinia pseudoacacia Black locust Fabaceae Rubus allegheniensis Allegheny blackberry Rosaceae Sambucus canadensis American elder Caprifoliaceae Spartina altemiflora Smooth cordgrass Poaceae Symphoricarpos albus Common snowberry Caprifoliaceae

54 Previous Recommendations and Unfunded Proposals Bartholomay et al. (1997) recommended additional monitoring of the effect of ozone concentrations on radial growth of eastern white pine.

Kohut et al. (1997) recommended the following research: • continued ozone fumigations to identify additional ozone-sensitive species in Acadia NP, and • further investigation into the effects on plants of the interactions between ozone and acid fog.

Eckert et al (1999) recommended the following ozone injury work: • continued foliar injury surveys on know sensitive species, • research to determine the effect oflong-term exposure to ozone on the genetic diversity of sensitive plant species, and • fumigation studies to evaluate the effects of ozone on the structure and dynamics of plant communities.

Kohut and Costich (2001) propose to evaluate the potential for ozone to serve as an agent of selection to reduce the genetic diversity of populations of native plants. Their objectives are to 1) characterize and compare the genetic diversity within and among populations of big-leaf aster, spreading dogbane, and Canada mayflower (Maianthemum canadense) from Cape Cod National Seashore (NS), Acadia NP, and Roosevelt Campobello International Park; 2) assess and'compare the distributions of sensitivity to ozone among sub-populations from each park; 3) determine whether the distributions of sensitivity to ozone differ among populations from the three parks; 4) analyze the relationships between the genetic diversities of the populations and the levels of ozone stress in the parks from which they were obtained; and 5) analyze the relationships between genetic diversity and the distribution of ozone sensitivity within the populations. The parks occur along a decreasing gradient of ozone exposure from Cape Cod NS in the south to Roosevelt Campobello International Park in the north. Kohut and Costich proposed to sample 20 SUb-populations of each species at each park. Analysis of the genetic diversity in the populations would be conducted using amplified-fragment length polymorphism (AFLP) markers. This proposal has not been funded.

Ozone Summary Ambient ozone has been monitored at Acadia NP since 1982. Data show an increasing trend in ozone concentrations, and in fact, the park was recently designated non-attainment for the ozone NAAQS.

Field surveys in the early 1980s detected foliar injury of white pine needles that was thought to be caused by ozone. Ozone fumigations in the late 1990s identified a number of ozone-sensitive species in the park; however, the fumigations suggested the observed white pine injury was not associated with ozone. Subsequent work linked the injury to a fungal infection. In spite of elevated ozone concentrations in the late 1990s, little injury was observed on ozone-sensitive species in the park. A recent ozone injury risk assessment indicates injury may be greater during years with moderate ozone concentrations, as the drought conditions that occur during years with high ozone concentrations likely limit ozone uptake.

55 Recommended additional work focuses on determining the ozone-sensitivity of additional species in the park and investigating the genetic diversity of identified ozone-sensitive species.

56 III. LONG-TERM NEEDS ASSESSMENT PROCESS Staff from Acadia NP and the NPS Northeast Regional Office met in November 2002 and agreed on the need to assess long-term air quality program, monitoring and research needs for the park. Staff further agreed that it was desirable to perform a park-specific assessment to supplement the Network-level monitoring needs evaluation that would be performed for Acadia NP and nine smaller NPS units in the Northeast (Le., the Northeast Temperate Network) in 2003-2004. While the Network-level "Vital Signs" assessment would identify monitoring needs that were common to a number of parks, Acadia NP would have additional air quality-related monitoring concerns because of its Class I designation.

In the spring of 2003, reports and data specific to air quality monitoring and air pollution effects in and near Acadia NP were reviewed and summarized as draft Sections I and II of this report. The draft sections were sent to 14 reviewers in June 2003. The reviewers included staff from the NPS, U.S. Geological Survey, EPA, and others. These reviewers are experts in the areas of air quality planning and regulatory activity, ozone effects on vegetation, deposition effects on soils and surface waters, and/or the effects of mercury on biota and ecological processes. None of the reviewers had previously conducted work in Acadia NP, although most had worked in other locations in the northeast U.S. or Canada and so were familiar with the park's air quality issues. Each reviewer was asked to read Sections I and II and suggest any supplemental or corrective information then provide a prioritized list of recommendations for additional air quality-related research and monitoring at Acadia NP.

Twelve of the 14 reviewers (Appendix A) provided comments and recommendations in July and August 2003. While some reviewers addressed just one topic, e.g., mercury bioaccumulation, others recommended additional projects in all areas of air pollution effects monitoring and research, and even suggested additions to the park's overall air quality program. Some reviewers prioritized their recommendations, but others did not assign priorities. The reviewers' comments were well thought-out and insightful, and the NPS is grateful for their input.

On January 27-28, 2004, NPS staff from Acadia NP and the Northeast Regional Office, along with staff from the MDEP, EPA, and FWS (Appendix B), met in Boston, Massachusetts, to discuss, refine, add to, and prioritize the list of recommendations. The group determined that some of the recommendations were already being accomplished through existing programs at the park, so deleted those recommendations from the list. Remaining recommendations were combined into broad categories, when appropriate. After agreeing on a final list of recommendations, the group developed a set of 11 potential ranking criteria (Table 9), rated the criteria in order of importance, and used the top six criteria to prioritize the list of recommendations. Staff from Acadia NP intend to use the ranking criteria developed at the January 2004 meeting when evaluating the merit of future proposals submitted to the park. The group also discussed the relationship between the Acadia NP air quality program assessment and the Vital Signs scoping and monitoring process for the Northeast Temperate Network. The group determined that many of the identified air quality program, monitoring and research recommendations for Acadia NP would not apply to other Network parks. For the recommendations that are applicable to other parks, Acadia NP can serve as a location for testing and refining air quality-related monitoring protocols. There is also the possibility that the

57 Northeast Temperate Network may be interested in supporting some of the identified monitoring projects.

In the summer of 2004, the entire draft report was sent out for a second round of review to nine natural resource managers who are routinely involved in air quality issues (Appendix C). Six of the reviewers provided comments and suggestions and those were incorporated in the final report.

Ta bl e 9 R a nk·mg cntena. fIor aIr quar lty pro1ects at Acadia NP CRITERIA IMPORTANCE Does the project have direct applicability to regulatory/policy/permit review decisions, i.e., will it support management activities? 1 Will the project address an existing or imminent threat to resources? 2 (tie) Will the project collect data on an unknown or emerging issue that could be a future threat to resources? 2 (tie) Is Acadia NP a critical location to conduct the proposed work? 4 Will the results of the project be transferable/useful to others, e.g., Region, ARD, EPA, other Federal Land Managers, and Parks 5 (tie) Canada? Will the project result in quantifiable data on air pollution baselines or trends? 5 (tie) Does the project provide opportunities for partnering to reduce costs, leverage other projects, etc.? 7 (tie) Will the project significantly advance the state of science on a specific air quality issue? 7 (tie) Is the project cost effective? 9 Is the project "basic" rather than "applied" science, e.g., a process- based study? 10 Will the project contribute to education/outreach efforts related to air pollution effects at Acadia NP? Note: after further consideration, the group decided this is not an appropriate ranking criterion, but rather is a park Natural Resource 11 Program objective that applies to all activities.

RECOMMENDATIONS Rather than assigning numeric rankings to each of the following recommendations, participants at the January 2004 meeting opted to categorize the recommendations as programmatic, or high, medium, or low priority. Recommendations within a category were not prioritized, and so are not listed below in order of significance. Meeting participants acknowledged that the medium and low priority recommendations are important; however, given limited time and resources, they agreed NPS will first try to accomplish high priority projects. Programmatic items address the overall philosophy of Acadia NP's Air Resource Management Program. Programmatic recommendations will be addressed by park staff as time and resources permit. High priority projects are those that received high scores under the ranking criteria listed above. Acadia NP and Northeast Regional Office staffwill seek investigators and funding for high priority projects. Medium and low priority projects received lower scores, typically because of an estimated high

58 cost for the project, the perceived limited ability to use resulting information in the policy or regulatory arena, the impression that Acadia NP is not the best location for the work, or the feeling that a project was more appropriate for a regional, rather than a park-specific, effort. Although Acadia NP and Northeast Regional Office staff will not actively solicit cooperators or funding for medium and low priority recommendations, the NPS remains interested in opportunities to accomplish those projects.

Participants'in the January 2004 meeting determined that they did not have enough information to prioritize all of the reviewer recommendations. Therefore, Acadia NP staff will seek additional guidance and input from experts on the following recommendations: 1) determining the need for monitoring concentrations and effects of lesser known, or "emerging", pollutants such as polybrominated diphenyl ethers and perfluorinated organic chemicals (contained in flame retardants, cosmetics, surfactants and pharmaceuticals), and 2) collecting additional sediment cores from park lakes to develop historic deposition estimates of a number of atmospherically-derived contaminants and determine if diatom species changes have occurred due to acidification or eutrophication.

Programmatic Category • Work closely with staff of the NPS ARD to ensure that air quality projects and resulting management decisions at Acadia NP are consistent with a Servicewide approach to identifying and quantifying air pollution effects and using that information in the policy and regulatory arena. • Emphasize projects that have management applicability, e.g., defining the extent and magnitude of air pollution effects on park resources, over those that are solely process­ based studies, e.g., determining the mechanism by which flux occurs. Seek and promote management-related projects. For proposals that fall into the category of "basic research", work with the investigators to incorporate management-related components into the proposal. • Consider proposals for manipulative experiments in Acadia NP on a case-by-case basis, and evaluate the projects in terms of likelihood of major and/or long-term impacts and cost of conducting environmental compliance. • Seek projects that investigate the deposition, concentration and effects of PBTs, heavy metals and other "non-traditional" air pollutants on park resources. It is important to emphasize that because of the number of mercury studies that have already been conducted in the park, Acadia NP is a good location for related work. • Expand and enhance interpretation and outreach efforts by maintaining and updating park Resource Management web pages, wayside exhibits, Visitor Center displays, and air quality brochures, and by placing files of relevant reports, articles and abstracts on the Acadia NP air quality website. • Require cooperators to participate in park science workshops to share results, consider interdisciplinary linkages and strategize ongoing priorities and coordination. • Strongly encourage cooperators, including those who worked in the park in the past, to publish project results in peer-reviewed scientific journals. Such publication will increase the value of, and access to, study results. Two major efforts summarizing past work at Acadia NP will be published in 2005. A special issue of the journal Environmental Monitoring and Assessment will focus on the studies conducted in the

59 paired watersheds at Acadia NP. In addition, the NERC Mercury Research Group will publish an article in the journal Ecotoxicology that documents the extent of mercury distribution in northeast North American surface waters, sediments and key biota and relates that distribution to depositional gradients, land cover, land use and topography. Work conducted at Acadia NP will be discussed in the Ecotoxicology article. • Coordinate with staff of the Northeast Temperate Vitals Signs Network to ensure that air quality-related monitoring at Acadia NP is consistent with, and supports, monitoring in other Network parks.

High Priority Category • Continue existing air quality programs and core air quality monitoring in the park, including continuation of ambient air quality monitoring and seasonal fresh water chemistry and biota sampling. This monitoring is essential to document changes in air quality over time. On a periodic basis, re-evaluate the park air quality program and add or delete monitoring to reflect new issues and priorities. • Expand outreach efforts to encourage more cooperators to work in Acadia NP. Such efforts could include organizing sessions on Acadia NP research at scientific meetings, hosting specialty workshops in the park, and publishing management articles in scientific journals. Stress that the comprehensive and long-tenn nature of monitoring conducted in the park makes it an ideal, and rare, location for additional study. Continue to provide access to the paired watershed study sites, and seek base funding for watershed maintenance and baseline data collection. Emphasize the infrastructure and databases available for the paired watersheds and encourage long-tenn, integrated studies that address not only air pollution and its effects, but also climate change, disease, invasive species, etc. Encourage collection of data that will increase understanding of how ecosystem processes in the two intensively monitored watersheds apply to other areas in the park. • Seek projects that improve the NPS' ability to establish critical loads for the park, i.e., projects that help identify pollutant concentrations above which specific deleterious effects may occur. Such projects could enhance understanding of total deposition (wet plus dry plus occult) of N, S, mercury or other pollutants; establish dose-response relationships between pollutant levels and biological or ecological processes; or detennine a resource-based rate of response to change in pollution levels. Estimates of total deposition should continue to be improved as methods for measuring dry and occult deposition become more reliable. • Emphasize projects that investigate pollutant effects on important biological and ecological endpoints. While there is infonnation regarding pollutant concentrations, particularly of mercury, in a variety of biota in the park, it is imperative to understand the implications of those pollutant levels. In particular, seek the following: 1) projects that study pollutant effects on behavior, reproductive success, survival, etc.; 2) studies that compare effects in high-versus-Iow pollution concentration sites; and 3) research that helps define the magnitude and extent of pollutant effects in the park. Consider holding a workshop to further defme and prioritize research needs relative to mercury and biota. • Analyze and synthesize existing data sets. For example, analyze invertebrate samples collected as part of the surface water quality monitoring program to detennine if there is a difference in invertebrate populations inhabiting streams with different alkalinity levels.

60 As another example, perform a statistical analysis of datasets collected through the core ambient air quality monitoring program to determine if some monitored components can be used as indicators of concentrations and trends in other components. This information would be very· useful if budget cuts force the park to scale back the ambient air quality monitoring program. • Determine the status of pollutant contamination in estuaries. While there is information about mercury in freshwater systems, the equally important estuarine systems of the park have not been evaluated. Study the bioaccumulation and trophic transport of mercury and other pollutants, such as PCBs and organochlorines, in park estuarine food webs. • Continue process-based mercury experiments in the park, particularly in the paired watersheds, including the following: 1) study the fate of newly-deposited versus "old" mercury, i.e., the amount of mercury retention in watersheds; 2) investigate the factors that influence mercury methylation in the park, e.g., the role of S and dissolved organic carbon in methylation, and methylation potential in upland soils; 3) determine how quickly the systems respond to changes in deposition; and 4) investigate the deposition and effects of all forms of mercury, e.g., elemental, methylmercury, etc. in Acadia NP ecosystems. Results obtained at Acadia NP could augment information collected through other research efforts, such as the Mercury Experiment To Assess Atmospheric Loading in Canada and the u.S. (METAALICUS) project in Ontario, Canada. Consider sponsoring a workshop to further defme and prioritize projects that would be appropriate for the paired watersheds.

Medium Priority Category • Investigate the long-term effects of ozone concentrations on plant genetic diversity. While field surveys have detected minimal amounts of foliar injury in Acadia NP, even during years with high ozone concentrations, it is possible genetic shifts may have occurred because of elevated ozone levels. • Study the interacting effects of ozone and acid fog on forested ecosystems. The red spruce studies conducted by Jagels and others in the 1980s suggested potential interacting effects between ozone and acid fog on tree foliage and growth, but the results were inconclusive. It would be useful to clarify the type and extent of any negative effects in the park. • Investigate the potential interacting effects of air pollution and climate change on natural resources in the park. Climatologically-induced changes in hydrology, ambient temperature, or UV could exacerbate existing air pollution-induced impacts or cause new problems. Potential interactions include: 1) changes in forest structure and nutrient cycling, resulting in increased N export to surface waters or soil nutrient imbalances; 2) acidification or eutrophication of surface waters from increased N export; and 3) increased ozone-induced foliar injury and growth effects of vegetation. Seek guidance from Washington Office staff on Servicewide climate change efforts and priorities. • Determine how much mercury is deposited directly into park estuaries from the atmosphere compared to the amount that is transported in streams from upland areas.

Low Priority Category • Expand the core ambient air quality monitoring program. Additional potential monitoring parameters include event-based wet mercury deposition, dry and occult

61 mercury deposition, methylmercury deposition, speciation of air toxics in particulate matter, ambient organochlorine monitoring, expansion of continuous Sand N deposition and passive ozone monitoring to a number of locations and elevations in the park, and monitoring concentrations of total mercury versus methylmercury in park streams. Some of these data, e.g., event-based wet mercury deposition and gaseous mercury concentration, have been collected at the park through special studies. It would be valuable to monitor other parameters on a short-term basis. • Monitor ozone-induced foliar injury of park vegetation. Include synoptic field surveys and installation of permanent field monitoring plots and biomonitoring gardens. Keep informed about studies conducted in parks with extensive ozone injury, such as Great Smoky Mountains NP, because those projects will continue to provide information that can be used at Acadia NP. • Study the potential direct and indirect effects of ozone on wildlife. • Investigate the effects of ozone on employees and visitors at Acadia NP. Recognize that while it is appropriate for the NPS to monitor ambient ozone concentrations at the park and provide access to the data, the responsibility for protection of human health from ozone rests with the EPA and MDEP. • Encourage, support, and participate in regional studies that investigate atmospheric chemistry and the primary air pollution sources and source areas that influence the region. Ideally such projects would be conducted under the auspices and guidance of the Mid-AtlanticlNortheast Visibility Union (MANE-VU) Regional Haze Planning Organization or a similar group. • Monitor pollutant concentrations in, and effects on, lichens. • Expand mercury concentration sampling to a wide variety of species and trophic levels. Initiate routine mercury concentration monitoring of biota. • Support a broad-based, regional study of potential temperate climate mercury complexation with chlorides and bromines in the air interface above sea waters, and subsequent deposition to landscapes, i.e., the "polar sunrise effect". • Participate in a regional air quality assessment that includes source apportionment analyses and models impacts of current and potentially-reduced emissions on pollutant concentrations and effects in the region. Components of such an assessment will likely be accomplished under the auspices ofMANE-VU. • Develop a routine estuarine monitoring program for contaminants. Results from the ongoing King et al. and EPA National Coastal Assessment efforts will likely provide insight on the locations, contaminants, and ecosystem components that would be best to monitor at the park.

62 IV. LITERATURE CITED Amirbahman, A., P.L. Ruck, 1.J. Fernandez, T.A. Haines and J.S. Kahl. In review. The effect of fire on mercury cycling in the soils of forested watersheds: Acadia National Park, Maine, USA. Submitted to Water, Air and Soil Pollution. 31 p.

Bank, M.S. and D. Krabbenhoft. 2004. Regional assessment of mercury bioaccumulation in stream dwelling amphibians and fish in parks in the Northeast Region, Southeast Region and National Capital Region. Proposal. 17 p.

Bank, M.S., C.S. Loftin, T.A. Haines and R.E. Jung. In press. Mercury bioaccumulation in two­ lined salamanders from streams in the Northeastern United States. Ecotoxicology. 32 p.

Bank, M.S., C.S. Loftin and A. Amirbahman. 2002. Effects of local and landscape heterogeneity on mercury loadings in palustrine frog species from Acadia National Park, Maine. Proposal.

Ballenger, E. and R. Chalmers. 2000. Evaluation of ultraviolet radiation attenuation in relation to water chemistry, habitat characterization and amphibian populations of wetlands at Acadia National Park. Progress Report.

Bartholomay, G.A., R.T. Eckert and K.T. Smith. 1997. Reductions in tree-ring widths of white pine following ozone exposure at Acadia National Park, Maine, U.S.A. Canadian Journal of Forest Research 27:361-368.

Bennett, J.P., R.L. Anderson, R. Campana, B.B. Clarke, D.B. Houston, S.N. Linzon, M.E. Mielke, and D.T. Tingey. 1986. Needle tip necrosis on eastern white pine in Acadia National Park, Maine: results of a workshop to determine possible causes. National Park Service, Air Quality Division. Denver, Colorado. Unpublished report. 8 p.

Berrang, P., D.F. Karnosky, R.A. Mickler, and J.P. Bennett. 1986. Natural selection for ozone tolerance in Populus tremuloides. Canadian Journal of Forest Research 16: 1214-1216.

Breen, R., W. Gawley, M. Fraser and H. Dumais. 2002. Lake Monitoring Report. 1998-2001. Acadia NP Natural Resource Report 2002-03. Acadia NP. Bar Harbor, Maine. 53 p.

Burgess, J.R. 1997. Mercury contamination infishes ofMount Desert Island and a comparative food chain Mercury study. M.S. Thesis, University of Maine. 60 p.

Chen, C. 2003. Personal communication.

Culbertson, C. Undated. Assessing ground water degradation and its impact on estuaries in Acadia National Park. Proposal. 4 p.

Culbertson, C., M. Nielsen, J. Caldwell and S. Vidito. 2001. Developing tools to monitor and predict effects of nutrient enrichment on estuaries at Acadia National Park. Annual Progress Report. 9 p.

63 Davis, R.B., D.S. Anderson, S.A. Norton, and M.C. Whiting. 1994. Acidity of twelve northern New England (U.S.A.) lakes in recent centuries. Journal of Paleolimnology 12: 103-154.

Doering, P.H., L.L. Beatty, A.A. Keller, C.A. Oviatt and C.T. Roman. 1995. Water quality and habitat evaluation of Bass Harbor Marsh, Acadia National Park, Maine. Technical Report NPSINESORNRlNRTRl95-31. National Park Service, New England System Support Office. Boston, Massachusetts. 147 p.

Eckert, R., R. Kohut, T. Lee and K. Stapelfeldt. 1999. Foliar ozone injury on native vegetation at Acadia National Park: results from a six-year (1992-1997) field survey. Unpublished report. 42 p.

Evers, D. 2003. An ecological risk assessment strategy for len tic systems in northern National Parks. Proposal. 4 p.

Evers, D.C., O.P. Lane and L. Savoy. 2003. Assessing the impacts of methylmercury on piscivorous wildlife using a wildlife criterion value based on the common loon, 1998-2002. BRI Report 2003-07 submitted to the Maine Department of Environmental Protection. BioDiversity Research Institute. Falmouth, Maine. 63 p.

Evers, D. and O. Lane. 2000. Assessing methylmercury availability in Maine's aquatic systems with the belted kingfisher, 1998-1999 (preliminary report). BRI report submitted to Surface Water Ambient Toxic Monitoring Program. BioDiversity Research Institute. Falmouth, Maine. 7 p.

Evers, D., P. Reaman, C. DeSorbo and P. Phifer. 1999. Assessing the impacts of methylmercury on piscivorous wildlife as indicated by the common loon. BRI Report 1999-01 submitted to the Maine Outdoor Heritage Fund. BioDiversity Research Institute. Falmouth, Maine. 38 p.

Evers, D.C., D. Yates and L. Savoy. 2002. Developing a mercury exposure profile for mink and river otter in Maine. Report BRI 2002-10 submitted to Maine Department of Environmental Protection and Maine Inland Fisheries and Wildlife. BioDiversity Research Institute. Falmouth, Maine. 22 p.

Fitzgerald, W.F. and D.R. Engstrom. 2001. Natural and anthropogenic sources ofmercury to the atmosphere: global and regional contributions. Proposal. 25 p.

Foley, M.K. 1987. Ecosystem disturbance and forest development in Acadia National Park. Ph.D. Dissertation, Boston University. Boston, Massachusetts. 238 p.

Golomb, D., E. Barry, G. Fisher, P. Varanusupakul, M. Koleda and T. Rooney. 2001. Atmospheric deposition of polycyclic aromatic hydrocarbons near New England coastal waters. Atmospheric Environment 35:6245-6258.

Greves, R. 2003. Personal communication.

64 Haines, T. 2001? Evaluate mercury contamination in aquatic environments of Acadia National Park and Cape Cod National Seashore. Unpublished report.

Haines, T., H. Webber and J. Coyle. 2000. An assessment of contaminant threats at Acadia National Park. Unpublished report. 81 p.

Harding ESE, Inc. 2002. Clean Air Status and Trends Network (CASTNet) 2001 annual report. Prepared for the U.S. Environmental Protection Agency.

Heath, R.H., J.S. Kahl, S.A. Norton and W.F. Brutsaert. 1993. Elemental mass balances, and episodic and ten-year changes in the chemistry of surface water, Acadia National Park, Maine: final report. Technical Report NPSINAROSSINRTR-93/16. National Park Service, North Atlantic Region. Boston, Massachusetts. 111 p.

Huntington, T., C. Culbertson, B. Kopp and IH. Duff. 2003. Fate of shallow ground water nitrate to Northeast Creek estuary: a threatened ecosystem at Acadia National Park. Proposal. 6 p.

Jage1s, R 1986. Acid fog, ozone and low elevation spruce decline. lAWA Bulletin 7: 299-307.

Jagels, R., J. Carlisle, R Cunningham, S. Serreze and P. Tsai. 1989. Impact of acid fog and ozone on coastal red spruce. Water, Air, and Soil Pollution 48:193-208.

Jiang, M. and R. Jagels. 1999. Detection and quantification of changes in membrane-associated calcium in red spruce saplings exposed to acid fog. Tree Physiology 19:909-916.

Johnson, K.B. 2002. Fire and its effects on mercury and methylmercury dynamics for two watersheds in Acadia National Park, Maine. Technical Report NPS/BSO-RNRlNRTRl2002-6. National Park Service, Boston Support Office. Boston, MA. 62 p.

Kahl, J.S. 1996. Lake chemistry at Acadia National Park, 1995. Unpublished report. 15 p.

Kahl, S. 1999. Responses of Maine surface waters to the Clean Air Act Amendments of 1990. Unpublished final report to U.S. Environmental Protection Agency. 37 p.

Kahl, J.S., S.A. Norton, T.A. Haines, E.A. Rochette, RH. Heath and S.C. Nodvin. 1992. Mechanisms of episodic acidification in low-order streams in Maine, USA. Environmental Pollution 78:37-44.

Kahl, J.S., T.A. Haines, S.A. Norton, and R.B. Davis. 1993. Recent trends in the acid-base status of surface water in Maine, USA. Water, Air, and Soil Pollution 67:281-300.

Kahl, S., D. Manski, M. Flora, and N. Noutman. 2000. Water resources management plan: Acadia National Park: Mount Desert Island, Maine. Unpublished report. 102 p.

65 Kahl, 1.S., K.C. Weathers, S.J. Nelson, and I.J. Fernandez: 2002. Correlating predictive contaminant deposition maps with streamwater chemistry at Acadia National Park. Proposal. 27 p.

Kahl, J.S., S. Nelson, A. Amirbahman, J. Eckhoff, 1. Elvir, I. Fernandez, H. Good, T. Haines, R Lent, G. Jacobson, K. Johnson, M. Nielsen, S. Norton, J. Parker, J. Peckenham, P. Ruck, M. Schauffler and G.B. Wiersma. 2003. Establishing paired gauged watersheds at Acadia National Park for long-term research on acidic deposition, nitrogen saturation, forest health, and mercury biogeochemistry (1998-2002). Unpublished report.

King, 1.W., C. Roman, and J. Latimer. Undated. Assessment oftrends in contaminant inputs and cultural eutrophication in Cape Cod National Seashore and Acadia National Park. Proposal. 6 p.

Kittredge, L.E. 1996. A geochemical analysis of lake waters and soils associated with three granites of variable fluoride concentration in Maine and New Hampshire, USA. M.S. Thesis, University of Maine. Orono, Maine. 95 p.

Kohut, R 2004. Personal communication.

Kohut, R., 1. Laurence, P. King and R Raba. 1997. Identification of bioindicator species for ozone and assessment of the responses to ozone of native vegetation at Acadia National Park. Unpublished report. 126 p.

Kohut, R, R. Eckert and T Lee. 2000. Field survey handbook: background and methodology used to conduct field assessments of ozone injury on native plants at Acadia National Park. Technical Report NPSIBSO-RNRlNRTRlOO-14. Department of the Interior. National Park Service, New England System Support Office. Boston, Massachusetts. 67 p.

Kohut, Rand D. Costich. 2001. Subtle loss ofplant genetic diversity from persistent air quality stress. Proposal. 20 p.

Lent, B., M. Nielsen and S. Kahl. Undated. Forested watershed nitrogen cycling and estuarine N loading at Acadia NP. Proposal.

Longcore, J.R and T.A. Haines. 1998. Tree swallows bioaccumulate mercury at Acadia National Park. George Wright Society Meeting Presentation. Asheville, North Carolina. (Summary Only)

Lubinski, S., K. Hop and S. Gawler. 2003. U.S. Geological Survey-National Park Service Vegetation Mapping Program, Acadia National Park, Maine. Unpublished report.

Matz, A.C. 1998. Organochlorine contaminants and Bald Eagles (Haliaeetus leucocephalus) in Maine: investigations at three ecological scales. Ph.D. dissertation, University of Maine. Orono, Maine. 120 p.

66 McNulty, S.G., J.D. Aber, T.M. McLellan and S.M. Katt. 1990. Nitrogen cycling in high elevation forests of the northeastern U.S. in relation to nitrogen deposition. Ambio 19:38-40.

Mower, B., J. DiFranco, L. Bacon and D. Courtemanch. 1997. Fish tissue contamination in Maine Lakes. Maine Department of Environmental Protection. Augusta, Maine. 14 p.

National Oceanic and Atmospheric Administration. 1988. A summary of selected data on chemical contaminants in sediments collected during 1984, 1985, 1986, and 1987. NOAA Technical Memorandum NOS OMA 44. National Oceanic and Atmospheric Administration. Rockville, Maryland.

National Park Service. 2002. Air quality in the national parks: second edition. National Park Service, Air Resources Division, Lakewood, CO. 59 p.

Neckles, H.A., J.R. Keough, C.W. Culbertson and G.R. Guntenspergen. Undated. The effect of nutrient loading on estuarine ecosystems: a stable isotope approach to study impacts on food webs. Proposal.

Nelson, S.J. 2002. Determining atmospheric deposition inputs to two small watersheds at Acadia National Park. Technical Report NPSIBSO-RNRlNRTRf2002-8. National Park Service, Boston Support Office. Boston, Massachusetts. 112 p.

Nelson, S.l, S.A. Norton and J.S. Kahl. 2003. Are seasonal patterns in marine tracers evidence of an oceanic source of Hg deposited on forested watersheds at Acadia National Park, Maine, USA? University of Maine. Orono, Maine. Unpublished report. 25 p.

Nelson, S.l 2003. Closing the loop on hydrologic and mercury mass balances for a temperate forested park. Proposal. lOp.

New England GovernorslEastern Canadian Premiers Forest Mapping Group. 2001. Protocol for assessment and mapping offorest sensitivity to atmospheric Sand N deposition. New England Governors/Eastern Canadian Premiers Acid Rain Action Plan. Action item 4: forest mapping research project. 79 p.

Nielsen, M.G. 2002a. Estimated quantity of water in fractured bedrock units on Mt. Desert Island, and estimated ground-water use, recharge, and dilutio1HJfnitrogen in septic waste in the Bar Harbor area, Maine. Open-File Report 02-435. U.S. Geological Survey. Augusta, Maine. 45 p.

Nielsen, M.G. 2002b. Water budget for and nitrogen loads to Northeast Creek, Bar Harbor, Maine. Water-Resources Investigations Report 02-4000. U.S. Geological Survey. Augusta, Maine. 32p.

Nielsen, M.G. 2003. Determining wetland susceptibility to hydrologic stresses in Acadia National Park. Workplan. 9 p.

67 Northeast Ecosystem Research Cooperative Mercury Research Group. 2003. Information at http://briloon.orgINERC/nerc2/index.htm.

Norton, S.A., J.S. Kahl, D.F. Brakke, G.F. Brewer, T.A. Haines, and S.C. Nodvin. 1988. Regional patterns and local variability of dry and occult deposition strongly influence sulfate concentrations in Maine lakes. Science of the Total Environment 72:183-196.

Norton, S.A., G.C. Evans and J.S. Kahl. 1997. Comparison of Hg and Pb fluxes to hummocks and hollows of ombrotrophic Big Heath Bog and to nearby Sargent Mt. Pond, Maine, USA. Water, Air, and Soil Pollution 100:271-286.

Norton, S.A., IS. Kahl, I.J. Fernandez, S. Datta and J. Farley. 2002. Assessment of current and historic atmospheric deposition a/toxic contaminants at Acadia National Park, Maine. Proposal. 30p.

Norton, S.A., 1.J. Fernandez, and A. Amirbahman. 2003. Abiotic controls on the trophic status 0/ oligotrophic water. Proposal. 15 p.

Pardo, L. 2003. personal communication.

Peckenham, J.M., IS. Kahl and A. Amirbahman. 2001. The impact a/vehicle traffic on water quality in Acadia National Park. Proposal.

Percy, KB., R. Jagels, S. Marden, C.K McLaughlin and J. Carlisle. 1993. Quantity, chemistry, and wettability of epicuticular waxes on needles of red spruce along a fog-acidity gradient. Canadian Journal of Forest Research 23:1472-1479.

Phillips, B.A. 1978. Bald Eagle management on Mt. Desert Island, Maine. B.A. Senior Thesis, College of the Atlantic. Bar Harbor, Maine. 39 p.

Sanchini, P.I 1986. Ozone injuries to Pinus strobus on permanent pine plots at Acadia National Park; 1985 survey results:final report. Unpublished report.

Shriver, W.G., D. Evers and T. Hodgman. 2002. Mercury exposure profile for sharp-tailed sparrows breeding in coastal Maine salt marshes. BRI Report 2002-11 submitted to Maine Department of Environmental Protection. BioDiversity Research Institute. Falmouth, Maine. 12 p.

Stafford, C.P. and T.A. Haines. 1997. Mercury concentrations in Maine sport fishes. Transactions of the American Fisheries Society 126:144-152.

Stoddard, J.L., J.S. Kahl, F.A. Deviney, D.R. DeWalle, C.T. Driscoll, A.T. Herlihy, J.H. Kellogg, P.S. Murdoch, J.R. Webb and KE. Webster. 2002. Response a/surface water chemistry to the Clean Air Act Amendments 0/ 1990. Unpublished final report to U.S. Environmental Protection Agency. 82 p.

68 Strobel, C. 2003. Personal communication.

Stubbs, C.S., R. Jagels and R. Homola. 1988. Biomonitoring environmental quality: lichen distribution and health on red spruce (Picea rubens L.). American Journal of Botany 75:10-11. (Abstract only)

Stubbs, C.S., R.L. Homola, J. Carlisle and S. Marden. 1990. Stability and change in lichen luxuriance and density on red spruce (Picea rubens Sarg.) in Maine. (Abstract only)

Sullivan, T.J. 1986. The lichens of Acadia National Park, Maine. American Journal of Botany 73:612 (Abstract only)

Taylor, G.E., R.J. Norby, S.B. McLaughlin, A.H. Johnson and R.S. Turner. 1986. Carbon dioxide assimilation and growth of red spruce (Picea rubens Sarg.) seedlings in response to ozone, precipitation chemistry, and soil type. Oecologia 70:163-171.

Treshow, M. 1984. Establishment o/white pine biomonitoring plots in Acadia National Park. Unpublished report. 81 p.

Treshow, M., E.K Sutherland and J.P. Bennett. 1986. Tolerance and susceptibility to air pollution, a new direction in sampling strategy: a case study of Pinus strobus L. in Acadia National Park, Maine. in Proceedings o/the International Symposium on Ecological Aspects 0/ Tree-ring Analysis. Marymount College. Tarrytown, New York. pp. 392-400.

U.S. Fish and Wildlife Service. 1992. The status of contaminants in Maine eagles - an interim report (draft). Fish and Wildlife Service Report FY92-NEFO-I-EC. U.S. Fish and Wildlife Service. Concord, New Hampshire.

VanArsdale, A., L. Alter, G. Keeler and T. Scherbatskoy. Undated. Mercury deposition and ambient concentrations of mercury in New England: results of a hybrid MDN and MIC-B network.

Weathers, K 2003. Personal communication.

Weathers, KC., G.E. Likens, F.H. Bormann, S.H. Bicknell, B.T. Bormann, B.C. Daube, 1.S. Eaton, J.N. Galloway, W.C. Keene, KD. Kimball, W.H. McDowell, T.G. Siccama, D. Smiley and R.A. Tarrant. 1988. Cloudwater chemistry from ten sites in North America. Environmental Science and Technology 22:1018-1026.

Weathers. K.C., G.M. Lovett and S.E. Lindberg. 2001. Atmospheric Deposition in Complex Terrain: Scaling Up to the Landscape at Acadia NP and Great Smoky Mountains NP. Proposal. 22p.

Webber, H.M. 1996. A comparison o/mercury in the through/all o/spruce and beech canopies. Unpublished report.

69 Webber, H.M. and T.A. Haines. 2003. Mercury effects on predator avoidance behavior of a forage fish, Golden Shiner (Notemigonus crysoleucas). Environmental Toxicology and Chemistry 22(7): 1556-1561.

Welch, L.J. 1994. Contaminant burdens and reproductive rates of bald eagles breeding in Maine. M.S. Thesis, University of Maine. Orono, Maine.

Wenner, N.G. and W. Merrill. 1998. Pathological anatomy of needles of Pinus strobus exposed to carbon-filtered air or to three times ambient ozone concentrations, or infected by Canavirgella banfieldii. Canadian Journal of Botany 76:1331-1339.

Wetmore, C.M. 1984. Lichens and air quality in Acadia National Park. Report to the National Park Service, Air Quality Division. Denver, Colorado. 39 p.

70 APPENDIX A. LIST OF ROUND 1 REVIEWERS

Tamara Blett Ecologist Air Resources Division National Park Service P.O. Box 25287 Denver, CO 80225

Art Chappelka, Ph.D. Professor Forest Biology School of Forestry & Wildlife Sciences Auburn University Auburn, AL 36849-5418

Celia Chen, Ph.D. Research Assistant Professor Department of Biological Sciences Gilman Hall Dartmouth College Hanover, NH 03755

Tom Clair, Ph.D. Research Scientist Environment Canada Box 6227 Sackville, NB E4L 3H6, CANADA

Christopher Eagar, Ph.D. Project Leader and Ecologist Northeastern Research Station U.S.D.A. Forest Service 271 Mast Road Durham, NH 03824

Neil Kamman Environmental Scientist IV Vermont Department of Environmental Conservation 103 S. Main Street, ION Waterbury, VT 05671-0408

71 Jim Latimer U.S. Environmental Protection Agency Atlantic Ecology Division 27 Tarzwell Drive Narragansett, RI 02882

Dee Morse Environmental Protection Specialist Air Resources Division National Park Service P.O. Box 25287 Denver, CO 80225

Joanne Rebbeck, Ph.D. Plant Physiologist U.S.D.A. Forest Service 359 Main Road Delaware,OH 43015-8640

James B. Shanley, Ph.D. Research Hydrologist U.S. Geological Survey P.O. Box 628 Montpelier, VT 05601

Greg Shriver, Ph.D. Northeast Temperate Network Coordinator National Park Service Marsh-Billings-Rockefeller NHP 54 Elm Street Woodstock, VT 05091

Charles Strobel Research Biologist U.S. Environmental Protection Agency Atlantic Ecology Division 27 Tarzwell Drive Narragansett, RI 02882

72 APPENDIX B. LIST OF MEETING PARTICIPANTS

John Monroe (Facilitator) Outdoor Recreation Planner Rivers and Trails Program National Park Service Northeast Region 15 State Street Boston, MA 02109

Bob Breen Biologist Acadia National Park P.O. Box 177 Bar Harbor, ME 04609-0177

Ian Cohen Environmental Scientist u.S. Environmental Protection Agency One Congress Street, Suite 1100 Boston, MA 02114

Sheila Colwell Natural Resource Program Manager National Park Service Northeast Region 408 Atlantic Avenue, Suite 228 Boston, MA 02110

Jeff Emery Air Monitoring Coordinator Maine Department of Environmental Protection 106 Hogan Road Bangor, ME 04401

Mary Foley, Ph.D. Regional Chief Scientist National Park Service Northeast Region 15 State Street Boston, MA 02109

73 APPENDIX C. LIST OF ROUND 2 REVIEWERS

Tamara Blett Ecologist Air Resources Division National Park Service P.O. Box 25287 Denver, CO 80225

Ellen Porter Biologist Air Resources Division National Park Service P.O. Box 25287 Denver, CO 80225

Holly Salazer Air Resources Coordinator Northeast Region National Park Service 207 Buckhout Lab University Park, P A 16802

Julie Thomas Environmental Protection Specialist Air Resources Division National Park Service 1849 C Street, NW Washington, DC 20240

Kathy Tonnessen Research Coordinator Rocky Mountain Cooperative Ecosystem Studies Unit School of Forestry University of Montana Missoula, MT 59812

David Welch Environmental Quality Ecological Integrity Branch, Parks Canada 25 Eddy Street, room 4-377, mail stop 25-4-S Gatineau, Quebec KIA OM5, CANADA

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