Uganik Island, Alaska Peninsula and Southwest Islands PALUSTRINE OPEN WATER

U.S. Fish and Wildlife Service Alaska Region Anchorage, Alaska USFWS

THE AUTHORS ACKNOWLEDGMENTS Jonathan V

. Hall coordinates the National This report is the result of extensive effort . Special Wetlands Inventory in the Alaska Region of the appreciation is extended to U . S. Fish and Wildlife U. S. Fish and Wildlife Service. Service personnel including Don Woodard, Becky Stanley, Tom

Dahl, NormMangrum, and Rene W . E . Frayer is Dean of the School of Forestry Whitehead of the National Wetlands Inventory and Wood Products at Michigan Technological Group, St . Petersburg, Florida; Charles Storrs of University. He specializes in natural resources the Division of Habitat Conservation, Atlanta, survey design and analysis . Georgia ; and David Dall of the National Wetlands Inventory, Washington, D C . Bill O . Wilen is Project Leader of the National Wetlands Inventory for the U. S . Fish and Many individuals from Geonex Inc. were respon Wildlife Service. sible for photo interpretation and map production Principal among these are Keith Patterson, DESIGN Sheila Ricardi, Marsha Martin, Todd Neurminger, Barbara Schuster, Jim Dick, and Gale Communications ; St . Paul, MN Dave Fink. Their work is greatly appreciated. Funding support fromthe U. S Army Corps of Cover photo

: Caribou, Arctic Coastal Plain Engineers and the National Oceanic and PALUSTRINE EMERGENT - FLOODED Atmospheric Administration's National Marine BP EXPLORATION (ALASKA) INC Pollution Program Office is gratefully acknowlBack cover photo: Yellow pond lily, edged . Glen Yankus of the U . S . Department of Cook Inlet - Susitna Lowland Interior's Minerals Management Service also S GALE assisted in the study.

## Status of

Arctic Coastal Plain PALUSTRINE OPENWATER AND EMERGENT - FLOODED

# Alaska Wetlands
by Jonathan V

. Hall, W . E. Frayer and Bill O

. Wilen 1994

BP EXPLORATION (ALASKA) INCPintails, Yukon Flats

PALUSTRINE EMERGENT - FLOODED USFWS

# Highlights

Alaska encompasses an area of 403,247,700 acres, including offshore areas involved in this study. Total acreage of wetlands is 174,683,900 acres. This is 43.3 percent of Alaska's surface area. In the lower 48 states, wetlands only occupy 5 .2 percent of the surface area. Deepwater habitats cover an additional 29,870,400 acres, or 7 .4 percent of Alaska's surface area. Over 88 percent (154,917,300 acres) of Alaska wetlands are under public management .

J HAL Palustrine scrub/shrub wetlands are extensive. They cover 114,510,100 acres, which is almost t"vo-thirds of Alaska's wetlands. Areas other than wetlands and deepwater habitats account for 198,693,400 acres, less than half of Alaska's area.

Brooks Range

PALUSTRINE SCRUB/SHRUB - SATURATED

# Contents Highlights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9 Classification System. . . . . . . . . . . . . . . . . . . . . . . . . .11 Survey Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 In Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29 Literature Cited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31 Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32 left. Safety Harbor ; Western Coastal Zone Mountain cranberry, KuskoklvimHigblancls ESTUARINE INTERTIDAL VEGETATED PALUSTRINE SCRUB/SHRUB - SATURATED J HALL D .DALL

7Y0CHAPTER ONE 

# Introduction

The United States Fish and Wildlife Service has

major responsibility for the protection and management of migratory and endangered fish and

wildlife and their habitats

. Of particular concern

are wetlands and associated deepwater habitats

. Since 1974 the Fish and Wildlife Service, through

its National Wetlands Inventory Project, has

inventoried the nation's wetlands

. The purpose is

to develop and disseminate comprehensive data

concerning the characteristics and extent of wetlands . Results of a National Wetlands Inventory study

of wetland gains and losses in the lower 48 states

between the 1950's and 1970's were published

by Frayer et al

. (1983) and Tiner (1984)

. Of the

wetlands at the time of settlement in the area

now comprising the 48 contiguous states, only

46 percent remained in the mid-1970's

. Between

the mid-1950's and mid-1970's, there was a loss

of about 11 million acres of wetlands

. During the

same period, approximately two million acres of

wetlands were created

. This 20-\,ear net loss of

nine million acres equates to an

aaverage annual

net loss of 458,000 acres of wetlands

. An update

of this report for the nine-year period between

1974 and 1983 showed the Nvedand loss rate was

down to an average annual net loss of 290,200

acres (Dahl et al

. 1991

; Frayer 1991)

.

left: Oil pipeline, Arctic Coastal Plain

PALUSTRINE EMERGENT - FLOODED J HALL right : Shaia

, Creek Flats,

Tanana-Kuskoklvim Lowland

PALUSTRINE SCRUB/SHRUB

AND EMERGENT - FLOODED

The statistical design used in the trend study for

the lower 48 states can be used with intensified

sampling to obtain reliable estimates for individual states or other selected geographical areas

. For example, this approach was used to evaluate

wetland trends in the Central Valley of California

(Frayer and Peters 1990) and Florida (Frayer and

Hefner 1992)

. This report presents results of a study on the status of wetlands and deepwater habitats in Alaska

. This is the first report for Alaska

. While it provides estimates of current status of Alaska wetlands and deepwater habitats, it does not provide

information on their trends and quality

. It does,

however, provide information on the amounts of

these areas managed by several federal agencies,

the State of Alaska, Natives and others

.

F GOLETCHAPTER TWO 

# Ovcrvicw

Wetlands in Alaska include types commonly referred to as bogs, muskegs, wet and moist tundra, fens, marshes, swamps, mud flats, and salt marshes The U.S. Fish and Wildlife Service estimates that during the 200-year period between 1780 and 1980, approximately 'ho of a percent of the original wetland acreage in Alaska was lost (Dahl 1990) . Common terms used for Alaska's deepwater habitats include lakes, bays, sounds, fjords, lagoons, and inlets . The two largest lakes in Alaska are Lake Iliamna (1,000 square miles) and Becharof Lake (458 square miles) . Large coastal deepwater habitats include Kotzebue Sound, Norton Sound, Bristol Bay, Cook Inlet, and the labyrinth of fjords, inlets, and straits in the Alexander Archipelago (southeast Alaska) . Lagoons formed behind barrier islands are common in northwest Alaska along the Chukchi Sea and Bering Strait coasts. Most regions of Alaska have a land surface that includes extensive areas of wetlands . Treeless expanses of moist and wet tundra underlain by permafrost occur in the northern and western portions . Interior Alaska contains millions of acres of black spruce muskeg and floodplain wetlands dominated by deciduous shrubs and emergents . Shrub and licrbaceous bogs are a conspicuous feature of the landscape in south central and southeast Alaska. Even in mountainous areas such as the Brooks Range, wetlands have developed in drainages and on vegetated slopes. Some of the nation's most extensive complexes of salt marshes and mud flats occur along the coasts of the Beaufort Sea, Chukchi Sea, Bering Sea and the Gulf of Alaska . left : Blying Sound, South Central Coastal Zone MARINE INTERTIDAL J HALL Wetlands are abundant in the valleys and basins associated with large river systems including the Yukon, Kuskokwim, Porcupine, Tanana, and Koyukuk Rivers. Significant wetland areas also occur on the major river deltas in Alaska. The Yukon-Kuskokwim Delta, one of the world's largest coastal deltaic formations, supports a variety of wetland types including wet tundra, grassy sloughs, shrub swamps, ponds and brackish marsh . Other major deltas in Alaska that are predominantly wetland are the Colville River Delta on the Beaufort Sea coast, the Copper River Delta in south central Alaska, and the Stikine River Delta in the southeast region. Many wetlands in northern portions of Alaska are underlain and maintained by permafrost, or perennially frozen ground. Wetland conditions often occur because the frozen layer traps water at or near the soil surface. Other wetlands are maintained by heavy rainfall, glacial melt water, river flooding, beaver activity, snow melt, springs, and the ebb and flowof tides . Wetlands in Alaska range in elevation fromtidal systems at sea level to moist tundra areas in high alpine zones. Wetlands are as common on slopes as they are in lowland sites and depressions . While north-facing slopes are frequently wetland due to the presence of permafrost, south-facing slopes in the same area often support non-wetland plant communities on `yell-drained soils. Hillside wetlands are common in southern portions of Alaska due to abundant precipitation and shallow depths to bedrock. Alaska's wetlands provide many benefits including: food and habitat for wildlife, fish and shellfish species, natural products for human use and subsistence, shoreline erosion and sediment control, flood protection, and opportunities for recreation and aesthetic appreciation. Not all wetlands perform all these functions, but most wetlands contribute to one or more in varying degrees .Tundra wetlands in northern and western Alaska are prime breeding grounds for many shorebirds (sandpipers, plovers, and their relatives) . Waterfowl species dependent on Alaska wetlands include more than 70 thousand swans, one million geese, and 12 million ducks (King and Lensink 1971) . These include more than half the continental populations of tundra and trumpeter swans and all or most of the continental populations of eight species or subspecies of geese. In recent years, Alaska wetlands have on average supported 30 percent of the continental populations of northern pintails, 24 percent of American wigeons, 19 percent of scaup, 18 percent of canvasback, and 13 percent of green-winged teal (Lensink and Derksen 1986) . The importance of Alaska wetlands to these and other species increases significantly during years when drought occurs in prairie states and provinces . During migration, huge flocks of waterfowl and shorebirds stop at specific wetland areas for resting and feeding. These critical wetlands provide concentrated food resources necessary to fuel the journey to nesting areas in the spring or southern destinations in the fall . Nearly all of the Pacific Flyway black brant feed on rich eelgrass beds at Izembek Lagoon on the Alaska Peninsula during fall migration (Fish and Wildlife Service 1985) . Many mammals in Alaska use specific wetland types and areas. Some species, such as beaver and muskrat, spend most of their lives in wetlands . Other mammals use wetlands primarily as feeding areas or resting areas. Moose commonly feed on submerged vegetation in deep marshes and shallowponds The two largest herds of caribou, both in northern Alaska, gather into huge aggregations and migrate fromupland areas to coastal wetland areas in the summer . Uninterrupted Snowgeese over Arctic Coastal Plain PALUSTRINE EMERGENT - SATURATED A BRACKNEY
moist tundra wetlands in the North Slope coastal plain are used by these animals for calving and feeding. Nonvegetated wetland types such as gravel bars and coastal beaches are used to escape insect harassment . The value of wetlands for fish is well established for Alaska's coastal wetlands along rivers and streams . Many fish species feed in wetlands or on food produced by wetlands . Coastal wetlands and stream side marshes are used as nursery grounds . Other wetland types adjacent to rivers maintain and regulate streamflowin channels used by fish. Species (e. g ., salmon) that move between fresh water and saltwater are dependent on both coastal and riparian wetlands . Annually, the salmon industry in Alaska employs approximately 22,000 people (Alaska Dept of Fish and Game 1992) . The annual value of this fishery to commercial harvesters is $600 million (Alaska Dept . of Education 1991) . Many wetlands serve to temporarily store flood waters, thereby protecting downstreamproperties from flood damage. The flood storage function also helps to slowthe velocity of water, which reduces the water's erosive potential . This function of wetlands becomes increasingly important in Alaska's towns and cities, where development has increased the rate and volume of surfacewater runoff and the potential for flood damage. Where permafrost is common, the ability of wetlands to store flood waters is reduced. Subsistence use of wetland resources in Alaska is extensive . In most areas, wetland habitats provide resources upon which Native village economies are based. A major portion of hunting, fishing, trapping, and gathering activities occurs in wetlands areas (Ellanna and Wheeler 1986) . Fish and wildlife resources harvested for subsistence use and dependent on wetlands include five species of salmon, shellfish, ducks, geese, beaver, and otter . Plant materials frequently collected fromwetlands include blueberries, cranberries, labrador tea, and willow

. The diversity of plant and animal life in wetlands makes thema valuable resource for nonconsumptive recreation such as wildlife viewing and photography. Wetlands, particularly in urban areas, are valuable in providing other passive recreation opportunities including education, open space, and aesthetic enjoyment . In addition, waterfowl hunting in the United States depends on continued productivity of Alaska's wetlands .CHAPTER THREE 

# Classification System

The definitions, classifications and categories of wetlands and deepwater habitats used are those described by Cowardin et al . (1979) . In general terms, wetland is land where saturation with water is the dominant factor determining the nature of soil development and the types of plant and animal communities living in the soil and on its surface . Technically, wetlands are lands transitional bemveen terrestrial and aquatic systems where the water table is usually at or near the surface or the land is covered by shallowwater . Wetlands must also have one or more of the following three attributes : 1) at least periodically, the land supports predominantly hydrophytes ; 2) the substrate is predominantly undrained hydric soil ; and 3) the substrate is nonsoil and is saturated with water or covered by shallowwater at some time during the growing season of each year . Deepwater habitats consist of certain permanently flooded lands. In saltwater areas, the separation between wetland and deepwater habitat coincides with the elevation of the extreme low water of spring tide. In other areas, the separation is at a depth of two meters (6.6 feet) belowlow water . This is the maximum

depth in which emergent plants normally grow

. Within the hierarchical structure of classification, wetlands and deepwater habitats are grouped according to systems . A system consists of environments of similar hydrological, geomorphological, chemical, and biological influences . Each

Color-infrared aerial photograph showing Kantishna River, Tanana-KuskokwimLowland system is further divided by the driving ecological force, such as ebb and flowof tide, and by substrate material and flooding regimes, or on vegetation life form

. Groupings of categories were made to accommodate special interests of the study, and to facilitate comparison of results with those of similar studies conducted in other regions of the United States .

### 1 2 The marine systemextends fromthe outer edge of the continental shelf shoreward to the extreme high water of spring tides or to the boundary of other systems as defined later . Marine subticlal includes that portion that is continuously submerged. This habitat is beyond the scope of the study and was therefore not included. Marine intertidal includes areas in which the substrate is exposed and flooded by tides, including the associated splash zone. The estuarine systemconsists of deepwater tidal habitats and adjacent tidal wetlands which are usually semi-enclosed by land, but have open, partially obstructed, or sporadic access to the open ocean and in which ocean water is at least occasionally diluted by fresh water runoff from the land. Estuarine subtidal is that portion that is continuously submerged (considered deepwater habitat), while estuarine intertidal is the portion exposed and flooded by tides, including the splash zone. For the purposes of this study, estuarine intertidal wetlands were separated into the following groups : Nonvegetated, which includes unconsolidated shore (e.g. mud flats) and aquatic beds (e .g. seagrasses or algal beds) ; and vegetated, which is primarily emergent. Emergent vegetation consists of erect, rooted herbaceous plants typically found in wet environments. The lacustrine systemincludes wetlands (littoral) and deepwater habitats (limnetic) situated in topographic depressions or dammed river channels . Each area must exceed 20 acres or be deeper than two meters (6.6 feet) or have an active wave-formed or bedrock shoreline feature . Lacustrine areas are treated as deepwater habitats in this study. The palustrine systemincludes all nontidal wetlands not included within any of the other four systems and does not include any deepwater habitats For this study, palustrine wetlands are divided into the following groups : unconsolidated shore, open water (primarily ponds), aquatic beds (e.g. pondlilies and pondweeds), emergent, scrub/shrub, andforested. Emergent is defined the same as for estuarine wetlands. Forested is characterized by the presence of trees, and scrub/shrub includes areas dominated by shrubs and small or stunted trees. Yukon-I,Cuskokwim Delta PALUSTRINE EMERGENT - FLOODEDAND OPEN WATER

F . GOLETPalustrine vegetated wetlands were further separated into categories of 

### saturated and 

### flooded. Saturated wetlands seldom have surface water, but the substrate is saturated for extended periods during the growing season Wetlands with organic soils, such as bogs, typically are saturated. Other examples of saturated wetlands include moist tundra and black spruce muskegs with permafrost occurring at a shallowdepth. 

### Flooded wetlands range fromtemporarily flooded to permanently flooded In temporarily flooded wetlands, surface water is present for brief periods during the growing season. Flooded wetlands in Alaska include marshes, wet tundra, riparian wetlands, and shrub swamps .



### Near Naknek, Bristol Bay Coastal Plain PALUSTRINE EMERGENT
- FLOODED

J HALL 49 In summary, the 14 wetland and deepwater habitat categories used in this study are : Category Marine intertidal Estuarine subtidal Estuarine intertidal nonvegetatEd Estuarine intertidal vegetated Palustrine unconsolidated shore Palustrine open water Palustrine aquatic beds Palustrine emergent - saturates Palustrine emergent - flooded Palustrine scrub/shrub - saturated Palustrine scrub/shrub - floodEd Palustrine forested - saturated Palustrine forested - flooded Lacustrine Common Examples Ocean shoreline Open water of bays/inlets Mud and sand flats/beaches Salt marsh Pond flats/beaches Open water ponds Floating and submerged aquatic vegetation Moist tussock tundra and sedge bogs Wet sedge/grass tundra and marshes Moist shrub tundra and shrub bogs/muskegs Shrub swamps Forested bogs/muskegs Forested swamps Lakes

It A 1 3

### 1 4 All remaining surface area (area not classed as wetland or deepwater habitat) corresponds to classes of agriculture, urban, and other used by Anderson et al . (1976) at their Classification Level I . Other includes Anderson's Level I classes of forest land, rangeland, and barren land, as well as lands that had been cleared of vegetation but had not been put to identifiable use. The type of ownership of wetlands was also determined in the study. For federal ownership, five categories were selected based on the management agency involved. These include the Bureau of Land Management, Fish and Wildlife Service, National Park Service, Forest Service, and other federal agencies. Additional ownership categories are Native, State and other . The results for individual categories are accurate for only one point in time. After transfers of federal land to Native and State ownership are completed, the samples involved in this study could be reclassified by ownership for timely results. This briefly describes the classification used in this study. It is difficult to differentiate the categories further without introducing highly technical terms . More detailed discussions, exact definitions, and fuller descriptions are provided by Cowardin et al . (1979) . Yukon-KuskokwimDelta

PALUSTRINE UNCONSOLIDATED SHORE

F GOLET

### CHAPTER FOUR 

# Survey Procedure

The objective of the study was to develop statistical estimates of the areal extent of wetland and deepwater habitat categories and ownership classes for Alaska. Astratified random

sampling design was used with 21 inland strata formed by modification of the land resource areas described by Rieger et al . (1979) . The study also used four coastal strata encompassing areas in the marine and estuarine systems . The 25 strata and Alaska's four major regions are shown in the map on page 16. Sample units were allocated to strata in proportion to expected amounts of wetlands and deepwater habitats as estimated by Fish and Wildlife Service personnel . A pilot study with 500 sample units was conducted to estimate the total number of sample units required for the statewide study. Kisarahk Lake, Kuskokwiyu Highlands LACUSTRINE

D .DALL 

### The total number of sample units used statewide was 2,566 . Each sample unit is a four-square mile area, two miles on each side . The units were plotted on U. S. Geological Survey topographic maps and on aerial photographs . The 1 : 60,000 scale colorinfrared aerial photography was obtained for the most recent date available. The average date of this photography was 1980, with 90 percent of the photos within three years of the average . The photography was interpreted and annotated in accordance with the classification system described earlier and with procedures developed by the Fish and Wildlife Service's National Wetlands Inventory Project A minimummapping size of one-half acre was used. Land ownership/management determinations were made from land information records maintained by the Bureau of Land Management .

1 5Southeast Coastal Zone South Central Coastal Zone Western Coastal Zone Northern Coastal Zone Southeast Alaska Mountains Southeast Alaska Lowlands South Central Alaska Mountains Cook Inlet -Susitna Lowland Alaska Peninsula and Southwest Islands Kuskokwim Highlands Koyukuk-Innoko Lowland Alaska Range Copper River Plateau Tanana-Kuskokwim Lowland Interior Alaska Highlands Yukon Flats Kanuti Flats Bristol BayCoastal Plain Bering Sea Islands Yukon KuskokwimDelta Norton Sound Highlands Selawik Kobuk Delta Brooks Range Arctic Foothills Arctic Coastal PlainCHAPTER FIVE 

# Results

The intent of this study was to quantify areal coverage of wetlands and deepwater habitats for Alaska. Results for all categories discussed in the classification system section are given in the Appendix . Several of the individual categories were grouped based on physical, chemical, and biological similarities and are shown as subtotals. These groupings include the following: Wetlands and deepwater habitats includes all marine, estuarine, palustrine, and paustrine classifications . Wetlands includes marine, estuarine, and palustrine wetlands . Estuarine wetlands includes all estuarine categories except estuarine subtidal (a deepwater habitat) Palustrine wetlands includes all palustrine categories. Palustrinc nonvegetated wetlands includes the unconsolidated shore, open water, and aquatic bed categories. Palustrine vegetated wetlands includes all emergent, scrub/shrub, and forested categories. Palustrine emergent wetlands, palustrine scrub/shrub wetlands, and palustrineforested wetlands include the saturated and flooded categories. Deepwater habitats includes estuarine subtidal and lacustrine habitats Results presented in the remainder of this section are based on information found in the Appendix and other supplementary data.
Alaska Range PALUSTRINE SCRUB/SHRUB - SATURATED

USFWS 1 7

### WETLANDS AND

DEEPWATERHABITATS The estimate of wetlands and deepwater habitats is 204,554,300 acres (See figure 1) . This represents 50.7 percent of Alaska's surface area. In the lower 48 states, wetlands and deepwater habitats only occupy 9

.3 percent of the surface area. Suckling Hills, South Central Alaska Mountains PALUSTRINE EMERGENT - SATURATED AND OPEN WATER 

### WETLANDS The estimate of wetlands is 174,683,900 acres. The lower 48 states contain an estimated 103,343,600 acres of wetlands (See figures 2, 3) . Figure 4 shows the distribution of Alaska wetlands by region.

1 8 z J . HALLALL SURFACE AREA WETLANDS
NON-WETLANDS 2,108,718,600 acres 88.4°/o Figure 1

Alaska Wetlands and Deepwater Habitats

OTHER WETLANDS 198,693,400 acres' 174,683,900 acres 49 .3% 43.3°,0

Figures 2, 3 Surface Area of Alaska and Lower 48 States

WETLANDS 278,027,500 acres 11 .6% DEEPWATER HABITATS 29,870,400 acres 7 .4%

Figure 4 Distribution of Alaska Wetlands by Region INTERIOR 70,665,700 acres SOUTHERN 40.4% 9,051,200 acres 5 .2%
ARCTIC AND WESTERN 92,776,400 acres 531% ALASKA WETLANDS LOWER 48 174,683,900 acres WETLANDS 62 .8% 103,343,600 acres 37 .2%

- COASTAL ZONE 2,190,600 acres 1 .3%

### Arctic Foothills PALUSTRINE EMERGENT - SATURATED The 25 physical subdivisions and four regions appearing in the map on page 16 are shown ALASKA PHYSICAL SUBDIVISIONS

below with their respective total acreages and wetland areas .

Coastal Zone acreage is primarily estuarine subtidal, a deepwater habitat USFWS

PHYSICAL SUBDIVISION TOTAL ACRES WETLAND

ACRES WETLAND PERCENT PHYSICAL SUBDIVISION TOTAL ACRES WETLAND

ACRES WETLAND PERCENT (INTHOUSANDS OF ACRES) (IN THOUSANDS OF ACRES) Southeast Alaska Mountains 7,023 .9 84.4 1 .2 Norton Sound Highlands 34,652.3 18,320.1 52.9 Southeast Alaska Lowlands 11,128 .4 3,835.5 34.5 Selawik-Kobuk Delta 3,149.6 2,384.0 75.7 South Central Alaska Mountains 26,375 .7 739.4 2.8 Yukon-KuskokwimDelta 15,860.3 12,477 .0 78.7 Cook Inlet - Susitna Lowland 9,442 .0 2,644.5 28.0 Bristol Bay Coastal Plain 6,067.5 3,331 .8 54.9 Alaska Peninsula & Southwest Islands 15, 748 .6 1,747.4 11 .1 Bering Sea Islands 2,898.1 2,194.5 75.7 Total - Southern Alaska 69,718.6 9,051 .2 13.0 Brooks Range 32;406.5 7,182.3 22.2 Arctic Foothills 36,390.6 30,271 .1 83.2 Copper River Plateau 8,367 .4 3,056.9 36.5 Arctic Coastal Plain 20,031 .5 16,615 .6 82.9 Alaska Range 18,197 .4 1,339.5 7.4 Total - Arctic & Western Alaska 151,456.4 92,776.4 61 .3 Koyukuk-Innoko Lowland 10,161 .0 7,223.0 71 .1 Kanuti Flats 1,339.0 1,023 .7 76.5 Southeast Coastal Zone 7,456.8 236.0 3.2 Tanana-Kuskokwim Lowland 13,550.9 8,256 .1 60.9 South Central Coastal Zone 6,567.7 694.1 10.6 Yukon Flats 9,679.2 3,681 .6 38.0 Western Coastal Zone 3,754.8 1,106.3 29.5 Kuskokwim

Highlands 44,182 .5 24,462.4 55.4 Northern Coastal Zone 3,592.3 154.2 4.3 Interior Alaska Highlands 55,223 .7 21,622.5 39.2 Total - Coastal Zone' 21,371 .6 2,190.6 10.3 Total - Interior Alaska 160,701 .1 70,665 .7 44.0 Total - Alaska 403,247.7 174,683.9 43.3

### Marine Intertidal Wetlands The estimate of marine intertidal wetlands is 48,600 acres . 

### Estuarine Wetlands The estimate of estuarine -,vetlands is 2,131,900 acres. This is smaller than the estimated 5,472,700 acres of estuarine wetlands in the lower 48 states (See figure 5) As shown in figures 6 and 7, the majority of estuarine wetlands in Alaska are nonvegetated; the vast majority of estuarine wetlands in the lower 48 states are vegetated . Figure 8 shows the distribution of Alaska estuarine wetlands by coastal subdivisions.
Figure 6 Estuarine Wetlands in Alaska

NONVEGETATED 1,771,700 acres 83.1 VEGETATED

360,200 acres 16 .9%

SOUTHEAST 230,800 acres 10.8% NORTHERN 144,300 acres 6 .8% NONVEGETATED 689,800 acres 12 .6%

Figure 8 Distribution of Alaska Estuarine Wetlands

by Coastal Subdivisions

SOUTH CENTRAL 675.900 acres 31 .7%

WESTERN 1 .080 .900 acres 50.7% Figure 5

Estuarine Wetlands in Alaska and the Lower 48 States

ALASKA LOWER 48 ESTUARINE ESTUARINE WETLANDS WETLANDS 2,131,900 acres 5,472,700 acres 28.0% 72.0°'0

Figure 7 Estuarine Wetlands in the Lower 48 States
VEGETATED 4,782,900 acres 87 .4%22 Palustrine Wetlands The estimate of palustrine wetlands is 172,503,400 acres. This represents 98 .8 percent of the wetlands in Alaska. Palustrine Nonvegetated Wetlands The estimate of palustrine nonvegetated wetlands in Alaska is 2,670,200 acres . The lower 48 states have 6,141,300 acres of palustrine nonvegetated wetlands . In both cases, most of the area is open water ponds However, in the mid-1950's, there was only an estimated 2,704,400 acres of palustrine nonvegetated wetlands in the lower 48 states . Most of the increase is due to pond construction. Caribou herd, Arctic Coastal Plain PALUSTRINE EMERGENT - FLOODED Palustrine Vegetated Wetlands The estimate of palustrine vegetated wetlands is 169,833,200 acres. This is much larger than the 91,625,300 acres in the lower 48 states (See figure 9) . The distribution is quite different for the two areas. In Alaska, the vast majority of palustrine vegetated wetlands are scrub/shrub wetlands, and the smallest amount is forested wetlands (See figure 10) ; in the lower 48 states, the majority of palustrine vegetated wetlands are forested wetlands, and the smallest amount is scrub/shrub wetlands (See figure 11) . The distribution of palustrine vegetated wetlands in Alaska's Southern, Interior, and Arctic and Western regions is shown in figures 12, 13, and 14, respectively.

BP EXPLORATION (ALASKA) INCFigure 9 Palustrine Vegetated Wetlands in Alaska and the Lower 48 States

ALASKA LOWER 48 169,833,200 acres 91,625,300 acres 65 .0% 35.0%

Figure 10 Figure 11 Palustrine Vegetated Wetlands in Alaska Palustrine Vegetated Wetlands in the Lower 48 States

EMERGENT 1,842,700 acres 20.8% SCRUB/SHRUB

114,510,100 acres 67 .4%

SCRUB/SHRUB 3,709,600 acres 42 .0% FORESTED 3,290,600 acres 37 .2% FORESTED 13,322,300 acres 7.9% 

# O PP" EMERGENT 42,000,800 acres 24 .7%

Figures 12, 13, 14 Palustrine Vegetated Wetlands by Region

EMERGENT 8,973,400 acres 12 .8% SCRUB/SHRUB 52,047,600 acres 74 .3%

FORESTED 8,989,300 acres 12 .9% SCRUB/SHRUB

15,344,500 acres 16.7% EMERGENT 24,533,000 acres 26.8% FORESTED

51,747,800 acres 56.5%

SOUTHERN INTERIOR ARCTIC & WESTERN SCRUB/SHRUB 58,752,900 acres 64 .6%
EMERGENT 31,184,700 acres 34.3% FORESTED

1,042,400 acres 1 .1%24 Palustrine Emergent Wetlands (Figures 15, 16) The estimate of palustrine emergent wetlands is 42,000,800 acres. The amounts of saturated and flooded wetlands are approximately equal . Palustrine emergent wetlands are most common in Arctic and Western Alaska, where threefourths of this type of wetland is found. Over 14 million acres of palustrine emergent wetlands are found in the Arctic Coastal Plain, the only physical subdivision in Alaska with the majority of its surface area in this single type . Over five million acres of palustrine emergent wetlands are found in the Yukon-ICuskokwim Delta and also in the Arctic Foothills. Palustrine Scrub/Shrub Wetlands (Figures 17, 18) The estimate of palustrine scrub/shrub wetlands is 114,510,100 acres. Only 5 .8 percent of these wetlands are classified as flooded Flooded palustrine scrub/shrub wetlands are most common in the Yukon- Kuskokwim Delta, where about onefourth of the palustrine scrub/shrub wetlands are flooded. Almost 97 percent of the palustrine scrub/shrub wetlands are found in Interior Alaska and Arctic and Western Alaska. Subdivisions having the most palustrine scrub/shrub wetlands are the Arctic Foothills in Arctic and Western Alaska, with 24,548,300 acres; and, the KuskokwimHighlands and the Interior Alaska Highlands in Interior Alaska with 18,858,900 acres and 16,348,900 acres, respectively. Palustrine Forested Wetlands (Figures 19, 20) The estimate of palustrine forested wetlands is 13,322,300 acres. Only 204,300 acres are classified as flooded . As shown earlier, palustrine forested wetlands cover relatively little area in Alaska compared to the lower 48 states, where it is the most abundant type of wetland.

Tanana-KuskokwimLowland I'ALUSTRINE SCRUB/SHRUB - FLOODED

F 30LETSATURATED VS FLOODED DISTRIBUTION BY REGION

SATURATED FLOODED 21,170,500 acres 20,830,300 acres 50.4% 49.6%

SATURATED 107,917,900 acres 94 .2%

SATURATED 13,118,000 acres 98 .5% Figures 15, 16

Palustrine Emergent Wetlands

Figures 17, 18 Palustrine Scrub/Shrub Wetlands

FLOODED 6.592 .200 acres 5 .8%

Figures 19, 20 Palustrine Forested Wetlands

FLOODED 204,300 acres 1 .5% ARCTIC AND WESTERN 31,184,700 acres 74 .2%

SATURATED VS . FLOODED DISTRIBUTION BY REGION INTERIOR 52 .047 .600 acres 45 .5%

SATURATED VS FLOODED DISTRIBUTION BY REGION
INTERIOR 8,989,300 acres 67 .5% INTERIOR

8.973 .400 acres 21 .4°0

ARCTIC AND WESTERN 58,752,900 acres 51 .3%

SOUTHERN

3,290,600 acres 24 .7% SOUTHERN

1,842,700 acres 4 .4%

SOUTHERN 3,709,600 acres 3 .2%

ARCTIC AND WESTERN 1,042 ;400 acres 7 .8%

### DEEPWATERHABITATS The estimate of deepwater habitats is 29,870,400 acres. Estuarine subtidal habitats cover approximately the same surface area in Alaska as in the lower 48 states (See figure 21) . Alaska has much less acreage in lacustrine deepwater habitats than the lower 48 states ; however, about t\vo-thirds of the lacustrine area in the lower 48 states is in the Great Lakes. OWNERSHIP The detailed ownership information collected during the study is presented in the summary table in the Appendix. The information should be used with caution, because the State of Alaska and Natives are continuing to receive lands selected fromthe block of lands managed by the Bureau of Land Management . This results in major shifts in wetland acreages managed by the Northwestern Lagoon, South Central Coastal Zone ESTUARINE SUBTIDAL 

### affected groups . Other shifts have occurred between groups due to land trades and acquisitions, and conversion of State lands to private ownership through homesteading and agricultural programs . Figure 22 shows the distribution of wetlands among ownership/management categories. The remaining figures show

acreages for wetland categories managed by the Fish and Wildlife Service, the National Park Service, and the Forest Service . Acreages in these groups have been relatively stable over the past several years. As might be expected, 1) the Fish and Wildlife Service is managing a greater proportion of emergent wetlands than the other two agencies, and 2) the most prevalent wetland category under Forest Service management is palustrine forested.

26 J HALLFigure 21 Figure 22

Estuarine and Lacustrine Deepwater Habitats Distribution of Wetlands by Ownership/Management in Alaska and the Lower 48 States LOWER 48 ESTUARINE SUBTIDAL 18,882,400 acres 17 .7%

LOWER 48

LACUSTRINE 57,842,800 acres 54 .3%

Wetlands under Management by Fish and Wildlife Service

PALUSTRINE SCRUB/SHRUB 24,151 ;900 acres 62 .9% PALUSTRINE EMERGENT 11,531,800 acres 30.1% ALASKA ESTUARINE SUBTIDAL 19,152,400 acres 18.0%

PALUSTRINE PALUSTRINE 

# I EMERGENT SCRUB/SHRUB 1,034,400 acres 11,332,900 acres 7 .8% 85 .5% OTHERS 564,700 acres 0.3% I STATE ALASKA 40,270,200 acres BUREAU OF LACUSTRINE 23.01° LAND MANAGEMENT 10,718,000 acres 58,824,900 acres 10.0% NATIVE - 33.7%

19,575,000 acres 11 .2%

NATIONAL

PARK SERVICE 13,259,700 acres Figure 23 7.6%

PALUSTRINE FORESTED 1,492,900 acres 3.9% \ OTHER WETLANDS 1,185,700 acres 3.1

PALUSTRINE FORESTED 780,500 acres 5 .9% \ OTHER WETLANDS 111,900 acres 0.8% FOREST SERVICE - 3,827,100 acres 2.2%

PALUSTRINE EMERGENT 370,000 acres 9.7% FISH AND WILDLIFE SERVICE 38,362,300 acres 22.0%

Figure 24 Figure 25 Wetlands under Management by National Park Service Wetlands under Management by Forest Service

PALUSTIRINE PALUSTRINE FORESTED SCRUB/SHRUB 2,649,700 acres 745,600 acres 69.211 % 19.5% i OTHER WETLANDS 61,800 acres 1 .6%CHAPTER SIX 

# In Conclusion

This survey provides an estimate of 174,683,900 acres of wetlands in Alaska, dominated by palustrine vegetated wetlands . Alaska contains 63 percent of the total wetland acreage in the United States (excluding Hawaii) . While widespread wetland losses have been relatively low in Alaska, specific localities have sustained significant losses (Alaska Dept . of Natural Resources 1993) . Results of this study provide the basis for future studies of wetland trends . One of the first trends that could be studied is the change in the ownership/management of wetlands resulting from continuing land transfers involving federal agencies, Natives, and the State of Alaska. The sample units used in this study could be reclassified by ownership at some future date to provide more current information .

left: Black spruce, Tauana-KuskokwimLolvland PALUSTRINE FORESTED - SATURATED J HALL right : Moose, Cook Inlet - Susitna LoiPland

PALUSTRINE EMERGENT - FLOODED Continual monitoring of surface area use and changes in use is needed to provide the basis for wise decisions This report is the result of one such method of monitoring initiated by the U. S . Fish and Wildlife Service The results in this report provide wetland information similar to 1) the forest and range information required by the Forest and Rangeland Renewable Resources Planning Act, and 2) information on soil, water, and related resources required by the Soil and Water Resource Conservation Act The results can be updated in the future on the schedule required by those Acts.

usLws 29

# Literature Cited

Alaska Department of Commerce and Economic Development . 1992. Seafood Industry Sector Report . State of Alaska, Dept . of Commerce and Econ. Dev ., Div. of Business Dev. 181 pp. Alaska Department of Education. 1991 . Alaska Blue Book 1991-1992, Ninth Ed State of Alaska, Dept . of Educ., Div. of State Libraries, Archives, and Museums. 369 pp. Alaska Department of Natural Resources . 1993. Alaska's outdoor legacy: statewide comprehensive outdoor recreation plan, 1992-1996. State of Alaska, Dept . of Natural Resources . 80 pp. Anderson, James R

., Ernest E . Hardy, John T. Roach, and Richard E . Witmer 1976. A land use and cover classification svstem for use with remote sensor data . U. S. Geol Suiv. Prof. Paper 964. 22 pp . Cowardin, L M

., V . Carter, F. C

. Golet, and E. T. LaRoc. 1979. Classificatio n of wetlands and deepwater habitats of the United States . U. S . Fish Wildl . Setv. 103 pp. Dahl, T. E. 1990. Wetland losses in the United States, 1780's to 1980's. U. S. Fish Wildl . Scrv. 21 pp Dahl, T. E., and C

. E. Johnson . 1991 . Status and trends of wetlands in the conterminous United States, mid-1970's to mid-1980's. U. S . Fish Wildl Scrv. 28 pp Ellanna, L. J ., and P. C

. Wheeler 1986. Subsistence use of wetlands in Alaska. In: Alaska Regional Wetland Functions - Proceedings of a Workshop . The Environmental Institute, Univ. of Mass. pp 85-103. left: Stikine River Delta, Southeast Alaska Lowlands PALUSTRINE EMERGENT - FLOODED J HALL Frayer, W . E., T J . Monahan, D

. C . Bowden, and F . A . Graybill . 1983 Status and trends of wetlands and deepwater habitats in the conterminous United States, 1950's to 1970's. Colo. State Univ. 32 pp . Frayer, W

. E., and Dennis Peters. 1989. Wetlands of the California Central Valley: Status and trends, 1939 to mid-1980's. U . S . Fish Wildl Scrv. 28 pp Frayer, W

. E. 1991 Status and trends of wetlands and deepwater habitats in the conterminous United States, 1970's to 1980's . Mich. Technological Univ. 32 pp. Frayer, W

. E ., and John Hefizer . 1991 . Florida wetlands : Status and trends, 1970's to 1980's . U . S Fish Wildl . Scrv . 32 pp. King, J . G., and C

. J . Lensink. 1971 . A

n evaluation of Alaska habitat for migratory birds . Unpublished report . Bureau of Sport Fisheries and Wildlife, Wash., D

. C . 72 pp . Lensink, C

. J ., and D. V Derksen. 1986 . Evaluatio n of Alaska wetlands for waterfowl . In: Alaska Regional Wetland Functions - Proceedings of a Workshop . The Environmental Institute, Univ. of Mass. pp 45-84. Rieger, Samuel, Dale B. Schoephorster and Clarence E . Furbush. 1979. Exploratory soil survey of Alaska. U. S Dept . Agr . Soi l Cons . Scrv. 213 pp. U. S. Fish and Wildlife Service. 1985. Izembek National Wildlife Refuge - comprehensive conservation plan . U. S . Fish Wildl . Serv., Anchorage, Alaska . 270 pp .

# Appendix

Estimates produced include acreages with associated standard errors . Many estimates are not considered reliable enough to recommend their use for making decisions. An indication is given of the reliability of each estimated acreage in the summary tables included in this appendix. The standard error of each entry expressed as a percentage of the entry (SE%) is given in parentheses. Reliability can be stated generally as "we are 68 percent confident that the true value is within the interval constructed by adding to and subtracting from the entry the SE%/100 times the entry." For example, if an entry is one million acres and the SE%is 20, then we are 68 percent confident that the true value is between 800,000 and 1,200,000 acres. An equivalent statement for 95 percent confidence can be made by adding and subtracting twice the amount to and from the entry Therefore, a large SE%indicates low reliability, if any, in the estimate . In fact, if the SE%is 100 or greater, we cannot even say that we are 68 percent confident that the true value is not zero. This discussion on reliability is meant to aid in interpretation of the study results . It was expected that only certain estimates would be precise enough to be meaningful . However, all entries are included in the summary table for additivity and ease of comparison.

Seaside plantain,

Anchorage, South Central Coastal Zone ESTUARINE INTERTIDAL VEGETATED Estimates were produced for categories described in Chapter Three . These estimates are summarized on the next page . Totals for columns are estimates of total acreage by ownership/management classification categor)T. Row totals (the extreme right column) are estimates of total acreage by surface area category. Entries are interpreted as in the following examples (all from the second and tenth columns of the table)

" " 11,531,800 acres classified as palustrine emergent are managed by the U. S. Fish and Wildlife Service. " " 42,000,800 acres are classified as palustrine emergent .

00
00

F GOLET 24,151,900 acres classified as palustrine scrub/shrub are managed by U. S . Fish and Wildlife Service . The estimate of palustrine forested area is 13,322,300 acres . The estimated area of wetlands and deepwater habitats is 204,554,300 acres.TABLE 1 . Area, in thousands of acres, by surface area classification.

Sampling error, in percent, is given in parentheses belowestimate. OWNERSHIP CLASSIFICATION FEDERAL BUREAU FISH AND NATIONAL ALL OF LAND WILDLIFE PARK FOREST OTHER ALL NATIVE STATE OTHER OWNERMGMT . SERVICE SERVICE SERVICE FEDERAL FEDERAL SHIPS MARINE INTERTIDAL WETLANDS 0 2 .9 0 0 0 2 .9 0 45.7 0 48.6 (42.9) (42.9) (31 .1) (29.7) NON-VEGETATED 0.6 58.0 5 .2 0.1 1 .3 65.2 7 .5 1698.0 1 .0 1771 .7 ESTUARINE (75.2) (44.0) (72.2) (55.0) (93.2) (39 .6) (53.2) (7 .9) (94.9) (7 .6) INTERTIDAL VEGETATED 5 .6 52.6 0.9 23 .6 4 .5 87 .2 17 .0 255.9 0.1 360.2 (45.6) (36.3) (54.6) (46.6) (87.0) (25.8) (37.4) (18.2) (95.0) (14.3) ESTUARINE WETLANDS 6.2 110.6 6.1 23 .7 5 .8 152 .4 24.5 1953 .9 1 .1 2131 .9 (41 .9) (30

.3) (69

.4) (46

.4) (71 .8) (23 .5) (33

.2) (7.4) (94 .9) (7.1) UNCONSOLIDATED 5 .4 15 .3 0 .1 <0 .1 0 20.8 1 .0 11 .2 0 33 .0 SHORE (54 .6) (83

.1) (81 .0) (100 .0) (62.8) (58 .1) (46

.3) (42 .5) OPEN WATER 489.8 992 .6 103 .3 37 .6 0.4 1623.7 549.4 336.4 1 .5 2511 .0 (9 .4) (7 .4) (20 .3) (31 .0) (99 .5) (5 .4) (13.7) (10 .2) (60

.7) (4 .1)

- AQUATIC BEDS 13.1 64.3 2.4 0.5 0 80.3 24.4 20.7 0.8 126.2 (30 .5) (22.8) (59.8) (55.2) (18.9) (24.2) (24.8) (99.3) (13.4) L NON-VEGETATED 508.3 1072.2 105.8 38.1 0.4 1724.8 574.8 368.3 2.3 2670.2 (9 .2) (7 .3) (20.0) (30.1) (99.5) (5 .4) (13.3) (10.0) (70.3) (4 .0) EMERGENT- 8252.2 5956.6 357 .1 205.9 0.1 14771 .9 1909.2 4483.0 6.4 21170.5 U SATURATED (10.4) (11 .5) (57.7) (19.6) (75.7) (7 .4) (16.4) (15.5) (66.4) (5 .9) EMERGENT- 6582.4 5575.2 677 .3 164.1 2 .5 13001 .5 3229.4 4586.0 13 .4 20830.3 FLOODED (8 .1) (9 .2) (24.5) (78.1) (88.7) (5 .6) (12.2) (9 .8) (78.1) (3 .9) S EMERGENT 14834.6 11531 .8 1034.4 370.0 2 .6 27773 .4 5138.6 9069.0 19.8 42000.8 (7 .4) (8 .0) (26.1) (36.8) (84.1) (5 .0) (10.8) (10.3) (57.9) (3 .5) SCRUB/SHRUB - , 38243 .3 22132 .0 10774.9 683.7 222.2 72056.1 12064.3 23708.9 88.6 107917 .9 SATURATED (5 .4) (6 .6) (14.3) (17.8) (52.7) (3 .7) (10.4) (7 .0) (49.2) (2 .4) SCRUB/SHRUB - 1372.3 2019.9 558.0 61 .9 36.1 4048.2 955.7 1566.3 22.0 6592.2 FLOODED (10.9) (12.5) (18.4) (55.9) (83.6) (7 .6) (20.8) (10.9) (55.8) (5 .9) SCRUB/SHRUB 39615.6 24151 .9 11332 .9 745.6 258.3 76104.3 13020.0 25275.2 110.6 114510.1 (5 .3) (6 .3) (14.0) (19.5) (48.2) (3 .6) (10.0) (6 .8) (49.1) (2 .3) I FORESTED- 3827 .9 1462.8 767 .1 2631 .2 103.7 8792.7 792.3 3483.9 49.1 13118.0 SATURATED (16 .2) (16.8) (43.5) (11 .0) (65.8) (8 .9) (22

.1) (12.7) (44 .4) (6

.7) FORESTED- 32.3 30.1 13 .4 18.5 2 .3 96.6 24 .8 74.2 8.7 204 .3 FLOODED (38 .2) (62

.6) (62

.6) (42

.4) (99

.4) (26

.1) (58

.5) (58

.3) (76

.6) (25

.7) FORESTED 3860.2 1492 .9 780.5 2649.7 106.0 8889.3 817 .1 3558.1 57 .8 13322.3 (16 .1) (16

.8) (42

.8) (10

.9) (64

.5) (8 .9) (22 .1) (12

.5) (42

.1) (6 .6) VEGETATED 58310.4 37176.6 13147 .8 3765.3 366.9 112767 .0 18975.7 37902.3 188.2 169833 .2 (4 .3) (5 .2) (13.1) (11 .3) (44 .9) (2 .8) (8 .5) (5 .7) (43.3) (1 .6) PALUSTRINE WETLANDS 58818.7 38248.8 13253 .6 3803.4 367 .3 114491 .8 19550.5 38270.6 190.5 '172503 .4 (4 .3) (5 .1) (13.01) (11 .2) (44.9) (2 .7) (8 .5 :1 (5 .6) (43.5) (1 .6) ALL WETLANDS 58824.9 38362 .3 13259.7 3827 .1 373.1 114647 .1 19575.0 40270.2 191 .6 174683 .9 (4 .3) (5 .1) (13.0) (11 .2) (44.2) (2 .7) (8 .5) (5 .4) (43.2) (1 .6) ESTUARINE SUBTIDAL 0.7 40.7 <0.1 <0.1 865.2 906.6 3 .9 18224.6 17 .3 19152 .4 (64.3) (65.1) (95.0) (95.7) (14.4) ` (14.0) (44.1) (1 .0) (95.0) (0 .8) LACUSTRINE 2496.5 2733.4 179.6 350.4 0 5759.9 1435.3 3519.7 3.1 10718.0 (12.8) (12.5) (28.1) (38.5) (8 .5) (15.7) (17.9) (99.2) (7 .5) DEEPWATER HABITATS 2497 .2 2774.1 179.6 350.4 865.2 6666 .5 1439 .2 21744.3 20 .4 29870 .4 (12.8) (12.3) (28.1) (38.5) (14A) (7 .6) (15.6) (3 .0) (82.0) (2 .7) WETLANDS AND 61322 .1 41136 .4 13439 .3 4177 .5 1238 .3 121313 .6 21014 .2 62014 .5 212 .0 204554 .3 DEEPWATER HABITATS (4 .2) 1 (5 .0) (12.8) (10 .2 (16.7) (2 .7) (7 .9) (3 .5) (39.9) (1 .3)