U.S. Department of the Interior

U.S. Geological Survey

Scientific Investigations Report 2015–5004

Prepared in cooperation with the U.S. Fish and Wildlife Service and 

North Dakota State University

Climate Change and Prairie Pothole Wetlands—Mitigating 

Water-Level and Hydroperiod Effects Through Upland 

Management
Cover. A cow standing in a dry wetland at Lacreek National Wildlife Refuge in South Dakota. Photograph by David M. Mushet, 

U.S. Geological Survey, October 13, 2004.
Climate Change and Prairie Pothole 

Wetlands—Mitigating Water-Level and 

Hydroperiod Effects Through Upland 

Management

By David A. Renton, David M. Mushet, and Edward S. DeKeyser

Prepared in cooperation with the U.S. Fish and Wildlife Service and 

North Dakota State University

Scientific Investigations Report 2015–5004

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

SALLY JEWELL, Secretary

U.S. Geological Survey

Suzette M. Kimball, Acting Director

U.S. Geological Survey, Reston, Virginia: 2015

For more information on the USGS—the Federal source for science about the Earth, its natural and living 

resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1–888–ASK–USGS.

For an overview of USGS information products, including maps, imagery, and publications, 

visit http://www.usgs.gov/pubprod

To order this and other USGS information products, visit http://store.usgs.gov

Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the 

U.S. Government.

Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials 

as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner.

Suggested citation:

Renton, D.A., Mushet, D.M., and DeKeyser, E.S., 2015, Climate change and prairie pothole wetlands—Mitigating 

water-level and hydroperiod effects through upland management: U.S. Geological Survey Scientific Investigations 

Report 2015–5004, 21 p., http://dx.doi.org/10.3133/sir20155004.

ISSN 2328-0328 (online)

ISSN 2328-031X (print)

ISBN 978-1-4113-3902-6
iii

Contents

Abstract...........................................................................................................................................................1

Introduction.....................................................................................................................................................1

Climate Change Effects on Prairie Pothole Wetland Hydrology ............................................................3

Modeling Wetland Response to Climate Change............................................................................3

Monitoring Wetland Response to Climate Change.........................................................................9

Upland Management Effects on Prairie Pothole Wetland Hydrology...................................................9

Grassland Grazing.................................................................................................................................9

Grassland Burning..............................................................................................................................12

Snow Management ............................................................................................................................13

Conclusions...................................................................................................................................................16

References Cited..........................................................................................................................................17
iv

Figures

1. Map showing extent of Prairie Pothole Region in North America.......................................2

2. Generalized view of a prairie pothole wetland water budget...............................................2

3. Graphs showing shifts in the cover cycle index for the Prairie Pothole Region

under several climate change scenarios .................................................................................5

4. Graph showing frequency of hydroperiod calculated for a seasonal prairie

pothole wetland ............................................................................................................................6

6. Graphs showing May ponds and waterfowl populations under different

scenarios of temperature and precipitation ............................................................................7

5. Graph showing estimated May breeding duck population and the average May

Palmer Drought Severity Index during 1955–96 for the north-central United States........7

7. Graph showing infiltration rates from 50-minute simulated rainfall event for

burned and unburned sites .......................................................................................................13

8. Diagram showing equilibrium drift geometry for a horizontal slat fence with 50

percent porosity placed on level terrain ................................................................................14

9. Diagram showing cross section of 1:30 model livestock pond...........................................15

Tables

1. Projected percentage of wet basins per year in the Prairie Pothole Region under

differing climate change scenarios...........................................................................................6

2. May Palmer Drought Severity Index, May ponds, and May duck populations for

historical conditions based on Geophysical Fluid Dynamics Laboratory Q-flux and

United Kingdom Hadley Center general circulation models .................................................8

3. Precipitation and runoff for differentially grazed watersheds............................................10

4. Mean wetland water levels for each land-use type under several climate change

scenarios......................................................................................................................................12
v

Conversion Factors

Inch/Pound to International System of Units

Multiply By To obtain

Length

inch (in.) 2.54 centimeter (cm)

Area

acre 0.4047 hectare (ha)

Mass

pound, avoirdupois (lb) 0.4536 kilogram (kg) 

International System of Units to Inch/Pound

Multiply By To obtain

Length

centimeter (cm) 0.3937 inch (in.)

millimeter (mm) 0.03937 inch (in.)

meter (m) 3.281 foot (ft) 

kilometer (km) 0.6214 mile (mi)

Area

hectare (ha) 0.003861 square mile (mi2) 

square kilometer (km2) 0.3861 square mile (mi2)

Flow rate

cubic meter per year (m3/yr) 0.000811 acre-foot per year (acre-ft/yr)

kilometer per hour (km/h) 0.6214 mile per hour (mi/h)

Temperature in degrees Celsius (°C) may be converted to degrees Fahrenheit (°F) as follows:

°F=(1.8×°C)+32

Temperature in degrees Fahrenheit (°F) may be converted to degrees Celsius (°C) as follows:

°C=(°F-32)/1.8
vi
Climate Change and Prairie Pothole Wetlands—Mitigating 

Water-Level and Hydroperiod Effects Through Upland 

Management

By David A. Renton1, David M. Mushet1, and Edward S. DeKeyser2

1

U.S. Geological Survey.

2

North Dakota State University, School of Natural Resource Sciences.

Abstract

Prairie pothole wetlands offer crucial habitat for North 

America’s waterfowl populations. The wetlands also support 

an abundance of other species and provide ecological services 

valued by society. The hydrology of prairie pothole wetlands 

is dependent on atmospheric interactions. Therefore, changes 

to the region’s climate can have profound effects on wetland 

hydrology. The relevant literature related to climate change 

and upland management effects on prairie pothole wetland 

water levels and hydroperiods was reviewed. Climate change 

is widely expected to affect water levels and hydroperiods of 

prairie pothole wetlands, as well as the biota and ecological 

services that the wetlands support. In general, hydrologic 

model projections that incorporate future climate change 

scenarios forecast lower water levels in prairie pothole 

wetlands and longer periods spent in a dry condition, despite 

potential increases in precipitation. However, the extreme 

natural variability in climate and hydrology of prairie pothole 

wetlands necessitates caution when interpreting model results. 

Recent changes in weather patterns throughout much of the 

Prairie Pothole Region have been in increased precipitation 

that results in increased water inputs to wetlands above losses 

associated with warmer temperatures. However, observed 

precipitation increases are within the range of natural 

climate variability and therefore, may not persist. Identifying 

management techniques with the potential to affect water 

inputs to prairie pothole wetlands would provide increased 

options for managers when dealing with the uncertainties 

associated with a changing climate. Several grassland 

management techniques (for example, grazing and burning) 

have the potential to affect water levels and hydroperiods of 

prairie pothole by affecting infiltration, evapotranspiration, 

and snow deposition.

Introduction

The Prairie Pothole Region (PPR) encompasses 

approximately 777,000 square kilometers (Smith and others, 

1964) ranging from central Alberta in Canada southward to northcentral Iowa in the United States (fig. 1). The PPR landscape is 

dotted with 5–8 million wetlands commonly called “potholes” or 

“sloughs” that were formed as Pleistocene Epoch glaciers receded 

around 12,000 years ago (Dyke and Prest, 1987). The wetlands 

formed where water accumulated in small depressions in a 

landscape that is underlain by low-permeability glacial till.

The climate of the PPR is highly dynamic and 

characterized by a west-to-east precipitation gradient, being 

drier in the west and wetter in the east (300–900 millimeters 

per year) and a north to south temperature gradient, being 

colder in the north and warmer in the south (average of 1–10 

degrees Celsius [°C]; Millett and others, 2009). Across the 

temperature gradient, the PPR also experiences great seasonal 

changes. Temperatures below -40 °C in the winter and above 

40 °C in the summer are not uncommon. Wind speeds in the 

PPR often exceed 60 kilometers per hour, greatly influencing 

evapotranspiration rates in the summer and movement of snow 

in the winter. Furthermore, the PPR climate fluctuates between 

wet and dry periods, with periods of deluge often being 

followed by drought (Winter and Rosenberry, 1998). Overall, 

the great climate variability is a key feature affecting PPR 

wetlands and the biotic communities that the wetlands support 

(Euliss and others, 1999).

The dynamic nature of the PPR climate creates wetlands 

of differing water permanence. Wetland types have been 

prescribed on the basis of water permanence and diagnostic 

vegetation that forms zones reflective of differing water 

depths (Stewart and Kantrud, 1971). Temporary wetlands 

are typically wet for a few weeks after snowmelt or after a 

heavy rainstorm and have a plant community that consists 

primarily of wet-meadow vegetation located in the central, 

deepest zone of the wetlands. Seasonal wetlands usually are 

dry by midsummer and have shallow-marsh vegetation that 

dominates the central zone of the wetlands. Semipermanent 

wetlands frequently have water for the entire growing season 
2 Climate Change and Prairie Pothole Wetlands—Mitigating Water-Level and Hydroperiod Effects Through Upland Management

but may be dry during years of drought. Deep-marsh emergent 

and (or) submergent vegetation characterizes the central zone 

of semipermanent wetlands. Groups of different classes of 

wetlands form what is known as wetland complexes (Johnson 

and others, 2010). However, a working definition of a 

“wetland complex” has yet to be defined.

Wetlands in the PPR are host to a variety of wildlife 

including invertebrates, fish, amphibians, reptiles, small 

mammals, and birds; most notably waterfowl. Many other 

groups of animals have been directly and indirectly affected 

by wetlands (Kantrud and others, 1989); however, waterfowl 

have received the most attention because of their monetary 

and sporting value and their high degree of dependence on 

wetlands of the PPR. The PPR consists of only 10 percent 

of the total waterfowl breeding habitat area in North 

America, yet it produces 50–80 percent of North America’s 

waterfowl populations (Batt and others, 1989). Thus, the 

PPR is a recreational hotspot for waterfowl hunters. The 

PPR also produces the birds that support recreational hunting 

opportunities along flyways and in overwintering areas 

outside of the PPR. Prairie pothole wetlands also provide a 

wide variety of benefits other than serving as aquatic habitats 

in a terrestrial landscape. The benefits include sediment 

entrapment, water-quality improvement, flood control, 

groundwater recharge, recreation, and aesthetic values 

(Kantrud and others, 1989; Leitch, 1996; Gleason and others, 

2008; Werner and others, 2013).

Despite the benefits that wetlands provide, they have 

historically been seen as a nuisance and a hindrance to 

agricultural production (Leitch, 1989). This misunderstanding 

has led to many PPR wetlands being filled, drained, or 

otherwise manipulated to facilitate crop production. In 

the conterminous United States it has been estimated that 

60–65 percent of PPR wetlands have been lost (Dahl, 

2014). Remaining prairie pothole wetlands are sensitive 

to changes in climate because of their dependence on 

atmospheric interactions (Winter and Rosenberry, 1998). 

Prairie potholes receive water through direct precipitation, 

runoff, and snowmelt. The potholes lose water primarily 

through evapotranspiration, which varies temporally and 

geographically in the PPR and is typically greater than 

inputs (fig. 2). Climate change can not only alter water 

inputs, but associated increased temperatures can enhance 

evapotranspiration rates as well. Interactions with groundwater 

often play a small role in wetland water budgets but can 

have significant effects on water chemistry (LaBaugh and 

others, 1998; Swanson and others, 2003). The net annual 

water budget of a prairie pothole wetland ranges from -10 to 

-60 centimeters (cm; Winter, 1989). Therefore, any change 

to water inputs from a changing climate has the potential 

to greatly affect water levels and hydroperiods (the period 

of time a wetland contains ponded water) of prairie pothole 

wetlands. However, changes in land use and management 

can alter evapotranspiration, infiltration, runoff, and snow 

dispersal patterns within a watershed, potentially providing a 

mechanism to mitigate climate change effects.

0 150 300 MILES

0 150 300 KILOMETERS

ALBERTA

MANITOBA

MONTANA

WYOMING

NEBRASKA

COLORADO

IDAHO

UTAH

NORTH

DAKOTA

SOUTH

DAKOTA

MINNESOTA

ONTARIO

IOWA

SASKATCHEWAN

115° 110° 105° 100° 95°

50°

45°

40°

Prairie Pothole Region

Figure 1. Extent of Prairie Pothole Region in North America.

Runoff

Indirect precipitation

Evapotranspiration

Direct precipitation

Overflow

Groundwater discharge

Infiltration

Groundwater recharge

Figure 2. Generalized view of a prairie pothole wetland 

water budget.
Climate Change Effects on Prairie Pothole Wetland Hydrology 3

The purpose of this study was to (1) summarize current 

(2014) research on the effects of upland management 

techniques on prairie pothole wetland water levels and 

hydroperiods and (2) identify potential upland management 

techniques that may be used to offset effects of climate change 

on valued wetland ecosystems. Accurate estimates of climate 

change are needed in order to estimate effects on wetland 

dynamics in the PPR; thus, the current (2014) literature on 

regional projections of climate change also was reviewed 

during the study.

Climate Change Effects on Prairie 

Pothole Wetland Hydrology

Temperature of the Earth’s atmosphere is predicted to 

increase between 1.5 and 4 °C by 2100 accompanied by an 

increase in total precipitation (Intergovernmental Panel on 

Climate Change, 2013). The increased patterns are anticipated 

to differ among regions. Temperatures are likely to increase 

between 3.7 and 6.1 °C in the Great Plains by the 2090s 

(Ojima and others, 2002). However, a greater warming trend 

is expected in the winter and spring compared to the summer 

or fall. Also, the number of frost-free days is expected to 

increase for the region, resulting in an earlier advancement 

of spring conditions (Meehl and others, 2004; Johnson 

and others, 2010). Precipitation is more difficult to model 

because of the great variability of the region. Nevertheless, 

precipitation is expected to range from -5 to +10 percent 

of current conditions (Intergovernmental Panel on Climate 

Change, 2013). The west to east precipitation gradient 

characteristic of the PPR may steepen or shift eastward 

under future climate scenarios (Johnson and others, 2005, 

2010). However, gains in precipitation will likely be offset by 

increased evapotranspiration rates resulting from increased 

temperatures and evaporative demands (Ballard and others, 

2014). Additionally, the frequency and severity of drought and 

deluge conditions are expected to intensify under an increased 

greenhouse gas climate (Ojima and others, 2002; Johnson and 

others, 2004; Intergovernmental Panel on Climate Change, 

2013).

Some of the changes associated with a globally 

changing climate have already been detected in the PPR. 

Air temperatures in the PPR have risen by 1 °C during the 

past century (Millett and others, 2009). The average increase 

in minimum daily temperatures has been greater than the 

average increase in maximum daily temperatures with the 

largest changes taking place during the winter (Millett and 

others, 2009). Additionally, the growing season in North 

Dakota has lengthened by an average of 1.2 days per decade 

from 1879 to 2008 (Badh and others, 2009). The trends are 

similar to those taking place in Canada (Zhang and others, 

2000) and reflect global average increases in temperature 

(Intergovernmental Panel on Climate Change, 2013). Across 

the PPR, precipitation varied by region but on average 

increased by 9 percent during the twentieth century (Millett 

and others, 2009). Most of the increased precipitation took 

place in the southeast part of the region (Ballard and others, 

2014) and during the last decade of the century (Garbrecht 

and Rossel, 2002). However, observed wetting trends are 

within the range of natural variability and therefore, might not 

continue (Ballard and others, 2014).

Modeling Wetland Response to Climate Change

Modeling of prairie wetland hydrology began with 

a spatial simulation model called WETSIM (WETland 

SIMulator). WETSIM consisted of two rule-based submodels 

that simulated hydrologic and vegetative dynamics of a 

prairie pothole wetland (Poiani and Johnson, 1991, 1993a, 

1993b; Poiani and others, 1995, 1996). The early versions 

of the WETSIM model (WETSIM 1.0–2.0) were set up and 

tested using data from a single semi-permanent wetland 

with a comprehensive hydrologic dataset. The effects that a 

changing climate would have on the prairie pothole wetland 

were explored by forcing different climate scenarios on the 

simulated wetland using the WETSIM model (Poiani and 

Johnson, 1991, 1993a; Poiani and other, 1995). Temperature 

and precipitation scenarios were based on current general 

circulation models at the time. The results of these initial 

climate-forcing experiments indicated that the simulated 

wetland would become less dynamic under a warming climate 

as predicted with a doubling of atmospheric carbon dioxide 

(CO2). Overall, water levels in the wetland were lower under 

scenario conditions as compared to historic conditions. The 

wetland also spent more time dry and choked by stands of 

emergent cover under the conditions simulated. The results 

indicated that climate change could have consequences for 

wildlife that depend on prairie pothole wetlands because of a 

decline in habitat quality.

WETSIM 1.0–2.0 only assessed surface processes 

as related to wetland dynamics and did not include land 

management as a variable. Thus, WETSIM 3.0–3.1 was 

developed to include groundwater interactions and integrate 

land management effects. WETSIM 3.1 and 95-year climate 

datasets from 18 weather stations located across the PPR 

were used to assess the effects of climate change across the 

PPR (Johnson and others, 2005). The three different climate 

scenarios that were simulated are as follows: (1) a 3 °C 

temperature increase, (2) a 3 °C temperature increase with 

a concurrent 20 percent increase in precipitation, and (3) a 

3 °C temperature increase with a 20 percent decrease in 

precipitation. Model results fluctuated with each treatment. 

A 3 °C temperature increase alone caused a shift of favorable 

water and vegetative cover conditions to the northern and 

eastern edges of the PPR. When temperature and precipitation 

were increased, the output was similar to the historical 

simulations. The increases in precipitation in conjunction 

with the temperature increase created a counterbalancing 

effect. A co-occurring increase in temperature and decrease in 
4 Climate Change and Prairie Pothole Wetlands—Mitigating Water-Level and Hydroperiod Effects Through Upland Management

precipitation had the greatest effect; causing favorable habitat 

conditions to shift to the very southeast corner of the PPR. In 

general, wetlands located in the drier, western parts of the PPR 

were determined to be most at risk. Only a substantial increase 

in precipitation was determined to ameliorate the effects of 

elevated temperatures (Johnson and others, 2005).

To overcome limitations of the WETSIM model, a new 

model was developed (Johnson at others, 2010). This new 

model, WETLANDSCAPE, was able to simulate wetland 

surface area, vegetation, and groundwater dynamics of 

multiple wetlands, specifically three temporary, three seasonal, 

and four semi-permanent wetlands. Within the set, interactions 

among wetlands could transpire by means of overland flow. 

Using climate data for the region, Cover Cycle Index (CCI) 

values were assigned for the complex. The CCI is a measure 

of the percentage of time a wetland spends in the hemimarsh stage (equal percentage of open water and emergent 

vegetation) and the number of cover-cycle stage changes. 

Prairie wetlands cycle among the following four stages: (1) a 

dry stage with thick emergent cover, (2) a regenerating stage 

where reflooding and subsequent germination from a seed 

bank take place, (3) a degenerating stage where emergent plant 

growth starts to decline because of high water, and (4) a lake 

stage where water is at a maximum and emergent vegetation 

is restricted to the shoreline (van der Valk and Davis, 1978). A 

complete cycle among the stages is called a wetland’s “return 

time” and potentially affects wetland productivity (Swanson 

and others, 2003). The CCI has not been rigorously evaluated; 

however, Johnson and others (2010) indicated that the CCI 

could be used as a metric of wetland productivity (i.e. higher 

CCI values represent higher productivity).

The WETLANDSCAPE model was calibrated using 

13 years of water-level and groundwater data and 3 years of 

field observations. Using 100-year datasets from 19 weather 

stations located across the PPR, temporal and spatial changes 

in wetland dynamics were detected. To test changes in wetland 

hydroperiod and CCI values, three future climate scenarios 

were applied. The scenarios included a 2 °C temperature 

increase, a 4 °C temperature increase, and a 4 °C temperature 

increase with a 10 percent increase in precipitation. With each 

2 °C temperature increase, the open-water (that is, ice-free) 

season extended by about 10 days (Johnson and others, 2010). 

A 4 °C temperature increase extended the open-water season 

by 13–26 percent. The temperature change had a greater effect 

on retracting spring thaw than on extending fall freeze, and the 

more permanent wetlands were affected greatest by a changing 

climate. Unexpectedly, temporary wetlands were determined 

to be the most resilient wetland type. In the historic 

simulation, the most favorable CCI class covered 47 percent of 

the PPR and was mainly located in the central PPR (Johnson 

and others, 2010). This region is known for its high waterfowl 

production (Batt and others, 1989). As the temperature was 

increased, the region with the highest CCI values shifted 

towards the east (fig. 3). With a 4 °C temperature increase, 

highest CCI values occurred in the very southeastern and 

northeastern areas of the PPR. The percentage of the favorable 

CCI values decreased to 30.8 and 12.5 percent for 2 and 4 °C 

temperature increases, respectively. When a 4 °C temperature 

increase was paired with a 10 percent precipitation increase, 

the results were similar to that of the 2 °C temperature 

increase scenario. In general, a 5–7 percent precipitation 

increase was needed to counteract a 1 °C temperature increase 

(Johnson and others, 2010). Water levels and hydroperiod also 

decreased significantly (fig. 4). A hydroperiod of 100 days 

historically occurred 22 out of 100 years; however, under 

a warmer climate this frequency would decline sharply 

(Johnson and others, 2010). The results of the model indicate 

that reductions in hydroperiod would likely have detrimental 

effects on wetland dependent species that require a minimum 

hydroperiod length for breeding or life cycle completion.

The WETLANDSCAPE model was also used to hindcast 

simulated wetland variability for the PPR over two 30-year 

periods (1946–75; 1976–2005). Using weather records for 

these two periods, wetland conditions were simulated to 

observe any changes that may have been because of climate 

change (Werner and others, 2013). Data from 19 weather 

stations located across the PPR were used to calculate the 

CCI values for each location for the two periods. Changes in 

temperature and precipitation caused changes in CCI values 

for the PPR. The area covered by the least productive CCI 

class increased from 40–47 percent for the 1946–75 and 

1976–2005 periods, respectively (Werner and others, 2013). 

The least productive CCI class increased primarily in the 

western part of the PPR. Air temperatures in the western 

region increased the most over any other part of the PPR. The 

most productive CCI class did not change in extent but instead 

shifted eastward. Precipitation in the southeast increased 

causing wetlands to become stuck in an open water stage 

and not cycle among cover stages as frequently; therefore, 

CCI values for this region decreased. Generally, there was 

a northeasterly shift in productivity within the PPR. The 

simulated changes in CCI values indicated that climate caused 

a sufficient enough change for the two time periods to produce 

significant changes in productivity (Werner and others, 2013).

Results from the WETSIM and WETLANDSCAPE 

models indicate that climate change may cause an eastward 

shift in the PPR of the most favorable areas for waterfowl 

(Johnson and others, 2005, 2010; Werner and others, 2013). 

However, the eastern part of the PPR has the most highly 

productive farmland; thus, the wetlands in the eastern part of 

the PPR have been extensively drained to accommodate crop 

production (Dahl, 1990, 2014; Tiner, 1984, 2003). Although 

wetland restoration in the PPR has been occurring since 

the 1960s (Knutsen and Euliss, 2001), only 1 percent of the 

wetlands in the eastern region of the PPR have been restored, 

primarily because of the high cost of obtaining easements 

on the productive farmlands (Johnson, 2005). However, the 

results should be interpreted with caution as modeled shifts in 

favorable wetland habitat may be because of a lack of spatial 

and temporal variation in the model design. Additionally, 

the CCI used in the WETLANDSCAPE model has not 

been evaluated rigorously as a metric for either wetland or 
Climate Change Effects on Prairie Pothole Wetland Hydrology 5

waterfowl productivity, and even assumed relations between 

semi-marsh conditions and productivity have recently been 

brought into question (Euliss and Smith, 2010).

Separate from the WETSIM and WETLANDSCAPE 

efforts, a set of models were developed based on analyses of 

waterfowl breeding and habitat survey data (Larson, 1995). 

Data consisted of waterfowl and wet basin counts from 

aerial surveys done in May of each year by the U.S. Fish and 

Wildlife Service and the Canadian Wildlife Service (Henny 

and others, 1972). Because of the large area covered by the 

surveys, these models accounted for geographic differences 

in wetland morphology. A post-hoc stratification of the survey 

data into U.S. grassland, Canadian grassland, and Canadian 

parkland regions was performed and each region was modeled 

independently. The models for Canadian grassland and 

parkland regions were created using data from 1968 to 1990 

and the U.S. grassland model was created using data from 

1973 to 1987 (Larson, 1995). Historical climate datasets 

that included monthly maximum, minimum, and average 

temperatures and total precipitation were also obtained 

(Larson, 1995). Linear regression was then used to explore 

the relations between the number of wet basins and climate 

for each of the three regions (Larson, 1995). The models were 

then tested and run for part of the study area to estimate model 

accuracy. The models explained 63–65 percent of the variation 

in number of wet basins for the three regions, indicating that rol14-0082_fig 03

A. Historic B. Temperature plus 2 degrees Celsius

C. Temperature plus 4 degrees Celsius

D. Temperature plus 4 degrees Celsius,

 Precipitation plus 10 percent

Modified from Johnson 

and others, 2010

EXPLANATION

Cover cycle index

0 to 0.22

0.23 to 0.43

0.44 to 1.0

0 150 300 MILES

0 150 300 KILOMETERS

0 150 300 MILES

0 150 300 KILOMETERS

0 150 300 MILES

0 150 300 KILOMETERS

0 150 300 MILES

0 150 300 KILOMETERS

115° 110° 105° 100° 95° 115° 110° 105° 100° 95°

50°

45°

40°

115° 110° 105° 100° 95° 115° 110° 105° 100° 95°

50°

45°

40°

50°

45°

40°

50°

45°

40°

Figure 3. Shifts in the cover cycle index for the Prairie Pothole Region under several climate change scenarios.
6 Climate Change and Prairie Pothole Wetlands—Mitigating Water-Level and Hydroperiod Effects Through Upland Management

climate is the primary driver in wetland dynamics (Larson, 

1995). The models accurately simulated the number of wet 

basins with the use of climate data, and the models held up to 

tests of random data deletion.

In order to elucidate the effects of climate change on the 

number of wet basins in the PPR, a set of six climate scenarios 

was imposed on the models (Larson, 1995). The six scenarios 

tested were +3 °C, +6 °C, +10 percent precipitation, +3 °C 

and +10 percent precipitation, -10 percent precipitation, and 

+3 °C and -10 percent precipitation. Effects were not uniform 

for each of the three regions (table 1). All regions experienced 

a decline in number of wet basins with an increase in 

temperature alone; however, the effects were greatest in the 

Canadian Parkland region. An increase in precipitation of 

10 percent resulted in an even increase in percent wet basins 

across all regions. A 10 percent precipitation increase was able 

to ameliorate some of the effects of an increase in temperature. 

A decrease in precipitation had a negative impact on the 

number of wet basins, with all regions affected similarly. 

The largest decrease in number of wet basins was a 3 °C 

increase and a 10 percent decrease in precipitation. Again, 

the Canadian Parkland region was most affected. Through 

this analysis, Larson (1995) was able to ascertain that PPR 

wetlands are sensitive to climate change and identified the 

Canadian Parkland region as being especially vulnerable.

In another attempt to link climate to the number of wet 

basins and waterfowl numbers, the Palmer Drought Severity 

Index (PDSI) was used as an indicator of habitat conditions 

and vulnerability of prairie pothole wetlands to climate change 

(Sorenson and others, 1998). The PDSI uses climate data 

to create a water budget that takes supply and demand into 

account. Monthly precipitation and temperature values are 

balanced using soil moisture, stored water, runoff, potential 

evaporation, and previous conditions. Values are normalized 

so that comparisons can be made among different geographic 

locations and time frames. The PDSI is a scale from approximately +8.0 to -8.0, with wetter conditions being reflected by 

higher values and drier conditions by lower values (Palmer, 

1965). May PDSI values were obtained for 22 climate divisions within the U.S. parts of the PPR during 1955–96. The 

PDSI values were then correlated with the number of wet 

basins and total duck populations from nine survey strata collected by the U.S. Fish and Wildlife Service (Henny and others, 1972). Results indicated that May PDSI values not only 

correlated strongly with the number of May ponds but also 

with breeding duck populations (fig. 5).

A model was then created using a linear regression 

between May PDSI values and the number of wet basins 

and total numbers of ducks, and then the model was tested 

to fit archival PDSI values from 1931 to 1990 (Sorenson and 

others, 1998). This model was used to simulate the number 

of wet basins and duck populations under scenarios that 

included temperature increases of 0, 1.5, 2.5, and 4.0 °C; and 

precipitation changes of -10, 0, +7, and +15 percent applied 

uniformly across all months. Changes in temperature and 

precipitation altered PDSI values, which in turn affected 

the number of May ponds and the breeding duck population 

(Sorenson and others, 1998; fig. 6). An increase in temperature 

of 1.5 °C alone caused the PDSI value to average -2.61 for 

April through August, which caused about a 40 percent 

decrease in the number of May ponds and the breeding duck 

population. Increases of 2.5 and 4.0 °C caused extreme 

rol14-0082_fig 04

0

5

10

15

20

25

30

35

40

60 80 100 120 140 160

Number of years (of 100)

Hydroperiod frequency, in days

22 years

7 years

1 year

EXPLANATION

Plus 4 degrees Celsius

Plus 2 degrees Celsius

Historic

Modified from Johnson and others, 2010

Figure 4. Frequency of hydroperiod calculated for a seasonal 

prairie pothole wetland. Vertical line shows frequency of a 100-

day hydroperiod.

Table 1. Projected percentage of wet basins per year in the Prairie Pothole Region under differing climate change scenarios.

[From Larson (1995); °C, degrees Celsius]

Region

Mean percentage of wet basins per year (percentage change in parentheses)

Historical +3 °C +6 °C +10 percent

precipitation

+3 °C and 

+10 percent 

precipitation

-10 percent

precipitation

+3 °C and

 -10 percent 

precipitation

Canadian parkland 51.5 22.4 (-56) 4.5 (-91) 57.2 (+13) 31.2 (-38) 36.3 (-28) 13.4 (-74)

Canadian grassland 49.2 42.0 (-15) 35.1 (-29) 55.0 (+12) 50.0 (+2) 38.9 (-21) 34.1 (-31)

U.S. grassland 51.4 36.4 (-28) 22.8 (-56) 57.8 (+12) 45.3 (-12) 38.2 (-26) 22.8 (-56)
Climate Change Effects on Prairie Pothole Wetland Hydrology 7

rol14-0082_fig 05

-6

-4

-2

0

2

4

6

0

2

4

6

8

10

12

55 58 61 64 67 70 73 76 79 82 85 88 91 94 97

Average May Palmer Drought Severity Index

Breeding population, in 

millions

Year Modified from Sorenson and others, 1998

EXPLANATION

Breeding population

May Palmer Drought Severity Index

Figure 5. Estimated May 

breeding duck population 

and the average May Palmer 

Drought Severity Index during 

1955–96 for the north-central 

United States.

0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

May ponds, in 

millions Breeding population, in 

millions

0

1

2

3

4

5

6

7

8

A

B

Modified from Sorenson and others, 1998

Temperature change, in degrees Celsius

0 +1.5 +2.5 +4

EXPLANATION

Plus 15 percent precipitation

Plus 7 percent precipitation

No precipitation change

Plus 10 percent precipitation

EXPLANATION

Plus 15 percent precipitation

Plus 7 percent precipitation

No precipitation change

Plus 10 percent precipitation

Figure 6. May ponds and waterfowl 

populations under different scenarios 

of temperature and precipitation. 

A, Simulated number of wet basins 

and B, simulated breeding waterfowl 

population. Dashed line represents the 

historical average during 1955–96.
8 Climate Change and Prairie Pothole Wetlands—Mitigating Water-Level and Hydroperiod Effects Through Upland Management

drought conditions with PDSI values less than -4 and losses 

of wet basins and duck populations by 70 percent or more. 

Increases in precipitation were able to compensate for some 

of the effects of higher temperatures but generally were 

not enough to negate the effects. Of the 12 scenarios that 

had increases in temperature, only 1 did not result in lower 

PDSI values; a 15 percent increase in precipitation fully 

compensated for the effects of a 1.5 °C temperature increase. 

Results from the simulations indicate that large increases in 

precipitation are needed in order to lessen the effects caused 

by increased temperature (Sorenson and others, 1998).

Sorenson and others (1998) also tested two general 

circulation models. The first general circulation model was 

developed by the Geophysical Fluid Dynamics Laboratory 

(GFDL Q-flux model; Manabe and Wetherald, 1987) and 

involved an immediate doubling of atmospheric CO2. The 

second model was developed by the United Kingdom Hadley 

Center (UKHC; Murphy and Mitchell, 1995) and involved 

a gradual increase of atmospheric CO2 by 1 percent each 

year. Simulations using the GFDL Q-flux and UKHC models 

revealed increased drought conditions and decreased numbers 

of May ponds and duck populations under a changing climate 

(table 2; Sorenson and others, 1998). The GFDL Q-flux model 

that doubled atmospheric CO2 levels caused average May 

PDSI values to drop to -3.40; the historical PDSI average 

was 0.37. The lower PDSI values were associated with a 

54 percent drop in May pond numbers and a 58 percent 

reduction in the breeding duck population. The UKHC model 

revealed that, by the 2020s and 2050s, May PDSI averages 

would drop to -1.41 and -2.59, respectively. May pond 

numbers would concurrently decrease by 23 and 38 percent 

for the 2020s and 2050s, respectively. This decrease in May 

ponds would cause duck populations to decrease 26 percent by 

the 2020s and 46 percent by the 2050s.

A similar approach was used to detect the effect of PDSI 

on wetland surface area in the PPR (Ouyang and others, 2014). 

The PDSI was correlated with wetland surface area obtained 

from 1986–2011 Landsat imagery, and a linear model able to 

predict wetland surface area under future climate scenarios 

was created (Ouyang and others, 2014). Using this model, 

wetland surface area fluctuated with changes in PDSI and was 

consistently lower for simulations based on Intergovernmental 

Panel on Climate Change (IPCC) fourth assessment report 

22-model ensemble climate. The average wetland surface 

area for the climate change scenario was 41.9 percent of the 

historical average. The PDSI values from previous years were 

also correlated with current-year wetland-surface-area values, 

with values from 1 year earlier having the greatest correlation 

(Ouyang and others, 2014). In conjunction with the results 

of Sorenson and others (1998), the PDSI was a good proxy 

measure for wetland surface area with changes in PDSI values 

because of climate change resulting in substantial effects on 

wetland dynamics (Ouyang and others, 2014).

Niemuth and others (2010) indicated that spatial and 

temporal variations in wetland dynamics are highly variable 

and complicate efforts to simulate changes in wetland dynamics caused by climate change. In an effort to detect spatial 

and temporal trends in prairie pothole wetlands caused by 

climate, wetland class, and geographic position; spatial and 

temporal patterns of roughly 40,000 wetlands within the PPR 

of North Dakota, South Dakota, and Montana were simulated 

(Niemuth and others, 2010). Each wetland within 263–380 

sample blocks was assessed with aerial photography taken 

in May of each year between 1988 and 2007. The period 

sampled included drought and deluge (Niemuth and others, 

2010). Percent wet area and percent wet basins fluctuated 

with the changes in climate. All sample wetland photography 

was digitized and wetlands were assigned a class category of 

temporary, seasonal, semipermanent, or lake. Then, a baseline 

was created using data from the National Wetlands Inventory 

(Wilen and Bates, 1995), and the baseline was used to compare the new data to estimate changes in percent wet area and 

percent wet basins. The baseline data were generated using 

historic wetland conditions during periods when wetland 

basins were full but not overflowing. Each wetland class 

was analyzed separately to determine if interannual wetland 

dynamics differed by wetland class.

Variability in percent wet area and percent wet basins 

was related to the permanence of the wetland, with temporary 

wetlands being the most variable and lakes being the least. 

Temporary wetlands consistently had the lowest percent wet 

area and percent wet basins, whereas lakes had the highest 

values for both. Correlations between current wetland conditions and previous conditions were highest for the lake regime 

and lowest for the temporary regime (Niemuth and others, 

2010). Effects of previous percent wet area values on current 

values were also analyzed (Niemuth and others, 2010). Conditions from 1 year earlier had the highest correlation to present 

conditions and steadily declined each year thereafter. Also, the 

Table 2. May Palmer Drought Severity Index, May ponds, 

and May duck populations for historical conditions based on 

Geophysical Fluid Dynamics Laboratory Q-flux and United 

Kingdom Hadley Center general circulation models.

[PDSI, Palmer Drought Severity Index; GFDL, Geophysical Fluid Dynamics 

Laboratory; UKHC, United Kingdom Hadley Center; CO2, carbon dioxide]

Scenario May 

PDSI

May 

pond 

numbers

(millions)

May 

breeding duck 

population 

(millions)

Historical (1955–96) 0.37 1.3 5.0

GFDL model (2 x CO2) -3.40 0.6 2.1

UKHC model 2020s -1.41 1.0 3.7

UKHC model 2050s -2.59 0.8 2.7
Upland Management Effects on Prairie Pothole Wetland Hydrology 9

percent wet area varied spatially for each regime and did not 

form a discrete east-west gradient of wetness.

Niemuth and others, (2010) noted several analysis limitations. Intra-seasonal effects could not be detected because 

wetlands were only sampled in May of each year. Current 

conditions and changes in land use surrounding the wetlands 

were not taken into consideration. Also, the results from the 

study were dependent on the baseline data used. Models developed within a limited spatial context and that precluded the 

use of the range of wetland classes may not reveal the complex variance among wetlands in the PPR. Therefore, further 

monitoring strategies and analyses of future wetland dynamics 

need to include greater spatial distribution and consider each 

wetland class separately (Niemuth and others, 2010). Also, 

factors such as intensified land use and wetland drainage may 

overshadow direct effects of climate change and need to be 

considered when making conservation decisions (Niemuth and 

others, 2014).

Climate change will differ spatially and temporally. Thus, 

model comparisons are needed that are not only conducted at 

large spatial scales but also consider seasonal changes. In such 

an analysis, Ballard and others (2014) explored climate model 

projections from phase 5 of the Coupled Model Intercomparison Project (CMIP5) of the IPCC Fifth Assessment in relation to PPR wetland hydrology. Model simulations revealed 

increases in precipitation across the PPR in all seasons except 

summer. However, the water-input gains were largely negated 

by increased evapotranspiration that accompanied increases 

in temperatures and evaporative demand. Seasonal surface 

drying in the summer corresponds to the combined effects of 

warming and precipitation changes (Ballard and others, 2014). 

However, uncertainties resulting from imperfect knowledge 

of future climates again necessitate caution when considering 

model results (Zhang and others, 2011).

Monitoring Wetland Response to Climate 

Change

Data compiled from wetland monitoring programs within 

the PPR are crucial to answering questions regarding the 

effects of climate change on wetland dynamics in the region. 

In a review of the monitoring strategies, current monitoring 

networks were determined to be insufficient to examine 

effects of climate and land use over a broad spatial scale 

(Conly and van der Kamp, 2001). For monitoring networks 

to be effective, two strategies, intensive and extensive, need 

to be implemented together (Conly and van der Kamp, 2001). 

The first strategy requires intensive monitoring of an array of 

hydrologic data at a relatively small number of sites. There 

are six such wetland-monitoring sites in Saskatchewan, one 

in North Dakota, and one in South Dakota. Conly and van der 

Kamp (2001) indicated that additions be made to the network 

to include areas that are highly sensitive to climate change. In 

addition to adding more sites, monitoring at these sites should 

include perspectives from several disciplines in a way that 

will increase our understanding of the complex interactions 

among wetlands within the PPR (Covich and others, 1997). 

Data such as streamflow, groundwater, and water quality 

should be included in intensive monitoring efforts to shed light 

on hydrologic and ecological interactions (Conly and van der 

Kamp, 2001).

Extensive monitoring consists of focusing on fewer 

hydrologic parameters and reducing sampling frequency 

but covering more wetlands over a broader geographic area. 

Climatic conditions account for a large percentage of the 

variation in water levels and hydroperiods of prairie pothole 

wetlands. However, land use surrounding wetland basins can 

have large impacts as well. Therefore, land-use data should 

be included in monitoring programs (Conly and van der 

Kamp, 2001; Covich and others, 1997). Multiple monitoring 

sites of similar catchment characteristics but with different 

surrounding land uses would meet this need (Covich and 

others, 1997). The data collected at such sites would be crucial 

to detect spatial differences in natural variation and variation 

caused by climate change and land use.

Upland Management Effects on Prairie 

Pothole Wetland Hydrology

A wetland’s water budget is a balance among 

precipitation, runoff, infiltration, and evapotranspiration 

(Shjeflo, 1968). Changes in climate can cause considerable 

effects on the amount of precipitation prairie pothole wetlands 

receive and the rate at which that water is lost through 

evapotranspiration. The water budget of a wetland is also 

altered through different upland management practices that 

affect runoff, infiltration, and evapotranspiration. Interception 

of snowfall and rainfall can also be altered through 

manipulations of vegetative cover. Wetlands in the PPR are 

located within a matrix of different land uses (Kantrud and 

others, 1989); therefore, an understanding of land-use impacts 

will be essential for making future management decisions 

under a changing climate. Farming practices can have 

profound effects on wetland conditions (Turner and others, 

1987) but are beyond the scope of this study. Instead, the 

focus is limited to the effects of management practices used on 

grasslands within the PPR.

Grassland Grazing

Grazing by livestock can cause changes in the hydrology 

of a watershed through the removal of plant cover and the 

physical action of animal hooves on vegetation and soils; 

however, these effects will differ across regions (Blackburn, 

1983). Uncontrolled grazing can have a negative effect on 

a watershed but can be managed with control of the timing, 

frequency, and intensity of grazing (Holecheck, 1981). 

The literature on the impacts of grazing on hydrology is 
10 Climate Change and Prairie Pothole Wetlands—Mitigating Water-Level and Hydroperiod Effects Through Upland Management

scattered with little information on its effects on prairie 

pothole wetlands. Therefore, our review also includes areas 

in proximity to the PPR with a focus on grazing impacts to 

evapotranspiration, infiltration, and runoff.

For prairie regions, evapotranspiration provides the 

largest deficit to the water budget (Frank and Inouye, 1994). 

An assessment of impacts of grazing on evapotranspiration 

rates for a grazed and ungrazed tallgrass prairie site indicated 

that evapotranspiration was reduced for the grazed site by 

an average of 28 percent and as much as 40 percent near the 

end and just after the grazing season (Bremer and others, 

2001). This difference was believed to be caused by changes 

in the vegetative canopy; leaf area index was 78 percent 

lower for the grazed site. However, after cattle were removed, 

evapotranspiration rates quickly increased and for a time 

were higher than the ungrazed site. The temporarily high 

evapotranspiration rates were the result of new leaf growth and 

delayed senescence. However, cumulative evapotranspiration 

was reduced by 6.1 percent on the grazed site. In addition to 

an overall reduction in evapotranspiration, grazing helped to 

conserve soil water in the upper 0.3 meter (m) of the soil profile.

A review of the literature on the effects of grazing on 

infiltration rates was completed by Gifford and Hawkins 

(1978) in an effort to detect an overall pattern across several 

regions. However, most of the studies were located in the 

western United States and the Great Plains. When infiltration 

rates of grazed pastures were plotted and compared to rates 

of ungrazed pastures, grazing impacts on infiltration rates 

were revealed. Although there was no significant difference 

between light and moderate grazing intensities, heavy 

grazing significantly reduced infiltration. Lower infiltration 

rates indicate that more water will be available as runoff to 

wetlands. However, conclusions were limited because of the 

lack of information on time-related effects of grazing, the use 

of data that were generally collected for other purposes and 

then reconfigured by range hydrologists, and the limitations of 

the instruments used.

Effects of grazing on vegetation and runoff were studied 

during 1962–67 within three range pastures. The pastures had 

been grazed since 1942 with the following grazing intensities: 

heavy, moderate, and light. In 1962, study sites consisting 

of four 2-acre plots within each of the three pastures were 

selected and H-flumes and FW-1 water-level recorders were 

installed on the downslope of each plot to record runoff. 

Rain gages were also installed on each watershed to record 

variations in precipitation. During 1963–67, hydrologic 

data were collected from May 14 through October 31, and 

vegetative data were collected in late July. Differences in 

runoff and vegetation were detected among the three grazing 

treatments (Hanson and others, 1970). Runoff was greatest for 

the heavy grazing treatment and lowest for the light grazing 

treatment with no detectable patterns in precipitation across 

the treatment sites (table 3).

Runoff regimes of the three watersheds were also altered 

by grazing. During the study period, there were 22, 18, and 

13 runoff events for the heavy, moderate, and light treatments, 

respectively. Smaller rainfall events produced runoff in the 

heavily grazed plots, whereas heavier rainfall events were 

needed to produce runoff in the lightly grazed plots. The 

total weight of vegetation remaining after grazing for the 

three treatments was 1752, 2092, and 3700 pounds per acre 

for the heavy, moderate, and light treatments, respectively. 

Also, the species composition was different for each of the 

treatment watersheds. The heavily grazed watershed consisted 

of sedges and short grasses, the moderately grazed watershed 

mostly consisted of short grasses with some midgrasses, and 

the lightly grazed watershed primarily consisted of western 

wheatgrass. This study only focused on the effects of cattle 

grazing during the growing season and not runoff from winter 

precipitation.

The effect of range condition on winter runoff and soil 

water storage was also studied (Hanson and Lewis, 1978). 

Desired range conditions were created using differing grazing 

intensities. During 1942–63, three pastures of good range 

Table 3. Precipitation and runoff for differentially grazed watersheds.

[From Hanson and others (1970)]

Year

Heavy grazing Moderate grazing Light grazing

Precipitation

(inches)

Runoff

(inches)

Precipitation 

(inches)

Runoff 

(inches)

Precipitation 

(inches)

Runoff 

(inches)

1963 12.14 1.79 12.02 1.57 12.61 1.39

1964 8.59 0.66 8.58 0.28 7.74 0.05

1965 10.81 0.13 11.05 0.14 10.91 0.12

1966 9.40 0.16 9.18 0.02 9.45 0.00

1967 11.00 1.21 11.16 0.79 10.90 0.54

Mean 10.39 0.79 10.40 0.56 10.32 0.42
Upland Management Effects on Prairie Pothole Wetland Hydrology 11

condition were grazed for 7 months each year under heavy, 

moderate, and light grazing intensities to produce range 

conditions of poor+, good-, and good+. Conditions improved 

to fair-, good, and excellent- during the duration of the study. 

Hereafter the pastures will be referred to as being of low, 

medium, and high range conditions. Within each of the three 

pastures, four plots were diked off. Runoff was measured 

using H-flumes and FW-1 water-level recorders, soil water 

was measured with a neutron probe at 30.5 cm intervals at 

122 cm depth, and precipitation was recorded at each site with 

four rain gages.

Average winter runoff values were not significantly 

different among the three range condition treatments (Hanson 

and Lewis, 1978). In general, the low condition range had 

higher fall soil moisture, whereas the high-condition range 

had lower fall soil moisture. The soil moisture differences 

can be explained by increased transpiration of the highcondition range because of the presence of more vegetation. 

Differences in spring soil moisture were less distinct, but the 

low-condition range typically had lower soil moisture than 

the medium- and high-condition ranges. Winter soil moisture 

was directly proportional to range condition, with the lowcondition range having less soil water than the high-condition 

range. Even though winter runoff values were similar for each 

range, the amount of winter precipitation stored in the soil was 

greatest for the high-condition range and lowest for the lowcondition range. The low-condition range not retaining snow 

as well as the high-condition range can explain differences 

in precipitation storage. The low-condition range had less 

standing vegetation and mulch because of excessive grazing; 

therefore, wind transported snow off the low-condition range. 

Conversely, the high-condition range had more standing 

vegetation and mulch. The vegetation and mulch held the 

falling snow and also trapped the snow transported by the 

wind. These results indicate that snow is an important source 

of soil moisture for the Great Plains.

During 1988–91, treatments of short duration and 

continuous grazing systems were applied on plots to assess 

the impacts of grazing on runoff and sediment yield (Naeth 

and Chanasyk, 1996). Grazing intensities of heavy and very 

heavy were compared against an ungrazed control. Snowmelt 

accounted for most of the annual runoff, and snowmelt runoff 

decreased with increased grazing intensity because of less 

snow entrapment on the grazed pastures. Sediment levels 

were low for snowmelt runoff and no trend among grazing 

intensities was detected. Rainfall runoff and sedimentation 

yield increased with increased grazing intensity.

The results presented in Naeth and Chanasyk (1996) were 

compiled using small treatment plots; therefore, Chanasyk and 

others (2003) validated the study by using watershed-scale 

treatment plots for 1998–2000. The Soil Water Assessment 

Tool (SWAT) was calibrated for the region in order to 

predict surface runoff (Chanasyk and others, 2003). Three 

similar watersheds were chosen and one of three treatments 

(ungrazed, heavily grazed, and very heavily grazed) was 

applied to each watershed. Each watershed had only one outlet 

where runoff could be measured. Climate and vegetative data 

were also collected at each study site. Surface runoff for all of 

the treatment sites was very low. Runoff events were sporadic 

and generally only lasted a few hours. The heavily and very 

heavily grazed watersheds consistently had higher runoff 

volumes than the ungrazed watershed; however, differences 

between heavily and very heavily grazed watersheds were 

not as clear. In fact, the heavily grazed watershed averaged 

more runoff during the study period than the very heavily 

grazed watershed. Vegetative cover decreased with increased 

grazing intensity; therefore, the grazing intensity did not 

help explain the observed differences. The difference in 

slope between the heavily grazed watersheds (average 

slope of 21 percent) and the very heavily grazed watersheds 

(average slope of 18 percent) was the only factor that might 

explain the unexpected results. Similar patterns were seen 

for snowmelt runoff. Snowmelt runoff only lasted for 2 days 

on the ungrazed watershed; however, snowmelt runoff lasted 

for 12 days on the treatment watersheds. The difference in 

snowmelt runoff days was unanticipated because expectations 

would be that the ungrazed watershed would have more snow 

because of more vegetative cover. However, the infiltration 

rate for this watershed would also be expected to be much 

greater and may help to explain results. Attempts at simulating 

runoff values for the watersheds were unsuccessful using the 

SWAT model. Values were consistently under predicted and 

may have been a result of the low levels of runoff during the 

study period and (or) the statistical criteria used (Chanasyk 

and others, 2003).

In another use of the WETSIM 3.2 model, water 

runoff, infiltration, and upland evapotranspiration rates were 

simulated under different land-use scenarios. The land-use 

scenarios were unmanaged native grass, unmanaged smooth 

brome grass, moderately heavy grazed native grass, spring 

burned grass, row crop, small grain, and alfalfa hay (Voldseth 

and others, 2007). The model was calibrated using data 

from 1993 to 2001 and was tested against 3 years of data 

collected after 2001. After calibration and testing, a 41-year 

simulation was run for the seven land-use scenarios using 

climate data from 1961 to 2001 (Voldseth and others, 2007). 

Land use was predicted to have an effect on water levels of 

wetland SP4 (Voldseth and others, 2007). Water levels were 

highest under the grazed simulation with a mean water level 

of 0.85 m, and the unmanaged grassland simulation had a 

mean water level of 0.67 m. The grazed grassland simulation 

predicted that wetland SP4 would be dry 22 percent of the 

simulation period, whereas the unmanaged native grassland 

would be dry 46.3 percent of the period. By using WETSIM 

3.2, Voldseth and others (2007) concluded that grazing could 

have a significant effect on prairie pothole wetland water 

levels because of changes in runoff, infiltration, and upland 

evapotranspiration caused by grazing cattle.

The potential of using management and farming practices 

as climate change mitigation strategies for prairie pothole 

wetlands was also tested using the WETSIM 3.2 model 

(Voldseth and others, 2009). Wetland dynamics in unmanaged 
12 Climate Change and Prairie Pothole Wetlands—Mitigating Water-Level and Hydroperiod Effects Through Upland Management

native grassland, unmanaged non-native grassland, grazed 

grassland, row crop, and small grain crop under historical 

climate conditions and several climate change conditions 

were modeled. The climate change simulations include +2 °C, 

+4 °C, +2 °C and +10 percent precipitation, +2 °C and -10 

percent precipitation, +4 °C and +10 percent precipitation, and 

+4 °C and -10 percent precipitation. Model runs revealed that 

changes in land use did have effects on wetland hydrology 

that, under certain scenarios, could ameliorate effects of 

climate change (table 4). Under all climate scenarios, wetlands 

with unmanaged native and non-native grass catchments had 

lower than historical water levels. The grazed grass treatment 

had the largest potential for mitigating climate change effects 

on prairie pothole wetlands (Voldseth and others, 2009). 

However, the simulation was based on small amounts of 

empirical data and further studies are needed to confirm the 

results.

Grassland Burning

Several studies have looked at the effects of fire on 

runoff and water yield outputs (for example, Robichaud and 

Waldrop, 1994; Helvey, 1980; DeBano, 2000; BenavidesSolorio and MacDonald, 2001). However, most research 

has focused on forested watersheds. In forested watersheds, 

fire generally increases water yield by altering patterns of 

evapotranspiration, infiltration, and runoff. Burning within 

a watershed reduces the amount of vegetative and mulch 

cover; thus, the amount of precipitation intercepted by the 

soil surface will increase. This water can then go back to the 

atmosphere through evapotranspiration, infiltrate into the soil, 

or runoff into a stream or wetland (DeBano and others, 1998). 

Evapotranspiration decreases immediately after a fire, likely 

because of temporary elimination of transpiring vegetation 

(Neary, 1995). Small decreases in evapotranspiration even 

can create relatively large increases in runoff (Ffolliott and 

Thorud, 1977). Infiltration rates after a fire often decrease as 

well because of the removal of organic material causing soil 

structure to collapse, raindrop impacts causing soil surfaces to 

compact, and (or) residue from ash causing soil pores to clog. 

Therefore, runoff will increase because of the decreases in 

infiltration and evapotranspiration (DeBano and others, 1998). 

Literature pertaining to the hydrologic effects of fire within the 

PPR is scarce. However, some generalizations can be made 

using data from other grassland watersheds.

The effects of prescribed burning on the surface 

hydrology of a tallgrass prairie were assessed by Koelliker 

and Duell (1990). The researchers established four plots; two 

plots were burned in May of 1989 and the other two plots 

were left unburned. Rainfall simulations were conducted 

throughout the following growing season on all of the plots. 

Initial infiltration rates were 19 millimeters per hour (mm/hr) 

lower for the burned plots; however, over longer timespans, 

differences decreased. Infiltration rates on one of the burned 

plots rebounded to the rate of the unburned plot after 40 days; 

infiltration on the other burned plot remained significantly 

lower. Runoff from the burned plots was initially 70 percent 

greater than the unburned plots. However, after 40 days 

runoff volumes were about equal between treatments. Runoff 

velocities were 10 percent greater for the burned plots but 

did not significantly increase erosion for slopes between 5 

and 10 percent. Prescribed burning caused an increase in 

runoff volume (Koelliker and Duell, 1990) even though 

evapotranspiration rates increased after a burn for the same 

area (Bremer and Ham, 1999).

The hydrologic effects of prescribed burning were 

assessed for oak, juniper, bunchgrass, and shortgrass 

dominated watersheds (Hester and others, 1997). Results 

from bunchgrass and shortgrass sites will be discussed. Each 

site was burned in July 1991. Following the burn, a drip-type 

rain simulator was used to determine infiltration rates and 

sediment yields from each of the burned and unburned sites. 

Rainfall events were simulated for 50 minutes at a rate of 

203 mm/hour and runoff was collected and measured every 

5 minutes. Vegetative and litter cover were also determined 

for each site, and soil was sampled and tested for texture, 

organic carbon content, and aggregate stability. Vegetation 

type had a strong impact on range hydrology (Hester and 

others, 1997). The shortgrass site had the lowest infiltration 

rate followed by the bunchgrass site. For both grassland 

sites, infiltration rates decreased over time for burned and 

Table 4. Mean wetland water levels for each land-use type under several climate change scenarios.

[From Voldseth and others (2009); °C, degrees Celsius; bolded values are equal to or greater than the historical value]

Land use

Mean water level (meters)

Historical +2 °C +4 °C

+2 °C and

+ 10 percent 

precipitation

+2 °C and

 -10 percent 

precipitation

+4 °C and

 +10 percent 

precipitation

+4 °C and

-10 percent 

precipitation

Native grass 0.67 0.54 0.43 0.62 0.46 0.49 0.37

Brome grass 0.66 0.53 0.41 0.61 0.45 0.48 0.36

Grazed grass 0.85 0.73 0.58 0.83 0.62 0.69 0.49

Row crop 0.80 0.66 0.52 0.76 0.56 0.62 0.44

Small grain 0.77 0.64 0.51 0.74 0.54 0.59 0.43
Upland Management Effects on Prairie Pothole Wetland Hydrology 13

unburned treatments. Burning affected the hydrology on all 

the vegetation types (fig. 7). On average, infiltration declined 

by about 25 and 28 percent for bunchgrass and shortgrass, 

respectively. Sediment yields for both grassland sites 

increases significantly; however, changes in soil structure 

were insignificant. The amount of sediment yield was strongly 

correlated with total organic cover, which had been completely 

removed in both grassland sites after burning. However, 

burning on slopes less than 20 percent for this region would 

not likely create serious erosion or water-quality problems and 

could be left to recover naturally (Wright and others, 1976).

As described previously, Voldseth and others (2007) 

used the WETSIM model to predict changes in wetland water 

levels caused by several land uses and management strategies. 

A spring burn simulation yielded similar results as grazing 

simulations. A spring burn simulation produced about a 

20-percent increase in average annual water level, compared 

to the unmanaged native grass simulation. However, empirical 

data and further research on the effects of prescribed burning 

on the hydrology of PPR grasslands and wetlands are needed 

to validate these findings (Voldseth and others, 2009).

Snow Management

Snowmelt is the most crucial water input to prairie 

pothole wetland water budgets, even though it only makes 

up roughly one-third of the annual water supply for much of 

the PPR (Shjeflo, 1968; Gray and Landine, 1988; Kantrud 

and others, 1989; LaBaugh and others, 1998). Snowmelt may 

account for as much as 80–85 percent of the total surface 

runoff for prairie habitats because of soils being frozen at the 

time of snowmelt (Gray and others, 1970). This snowmelt 

runoff provides an initial surplus of water that is available 

for waterfowl early in the season. The input from snowmelt 

alone can generally last until early July. However, additional 

rainfall is needed to sustain wetland water levels for the 

season (Shjeflo, 1968). For many northern and high altitude 

regions, water from snowmelt is essential for streamflow, soil 

moisture, groundwater recharge, and human use (Pomeroy 

and Gray, 1995). Because of the importance of snowmelt to 

prairie pothole water levels, many techniques have been used 

to manage snow in ways that provide increased water output 

from snowmelt.

After snow has been intercepted by the landscape it is 

readily moved by wind, causing its distribution and structure 

to change. Snow is transported until it forms drifts because 

of vegetation, topography, or manmade barriers. As snow 

forms drifts, the snow not only becomes deeper, but also 

denser as the snow is packed together and individual flakes 

lose their crystalline structure. This process is known as snow 

metamorphism and is caused not only by the physical action 

of snow packing but also by temperature and water vapor 

gradients (Pomeroy and Gray, 1995). Drifted snow has been as 

much as six times denser after a period of less than 24 hours 

for a site on the Canadian Prairies (Gray and others, 1970). As 

a snowdrift becomes larger and denser, snow water equivalent 

increases (Pomeroy and Gray, 1995). Snow water equivalent 

is the measure of how much water is stored within a given 

volume of snow and can be calculated from snowpack depth 

rol14-0082_fig 07

Modified from Hester and others, 1997

125

175

75

225

Infiltration rate, in millimeter per hour

5 10 15 20 25 30 35 40 45 50

Time, in minutes

Bunchgrass

Bunchgrass burned

Shortgrass

Shortgrass burned

EXPLANATION

Figure 7. Infiltration rates from 50-minute simulated rainfall event for burned and unburned 

sites.
14 Climate Change and Prairie Pothole Wetlands—Mitigating Water-Level and Hydroperiod Effects Through Upland Management

and density. Snow water equivalent can also be affected by 

ambient temperature, heat exchange within the snow pack 

from condensation, radiation and conduction, and percolation 

of water through the pack (Gray and others, 1970). 

Snow accumulation can be managed with the use of 

manmade or vegetative barriers. Manmade snow fences 

primarily consist of three types; horizontal wood slat, vertical 

wood slat, and synthetic fences. The horizontal-slat fence is 

typically used for permanent fences to control snow drifting 

across highways (Tabler, 1991), whereas the vertical-slat 

and synthetic fences work better for temporary snow fence 

designs. Synthetic fencing most commonly consists of 

perforated plastic sheeting or extruded plastic netting (Tabler, 

1994). Temporary fences may be preferred to trap snow in 

wetland basins as they can be easily dismantled during snow 

free periods.

Vegetative barriers can range in size from short stature 

grass strips to tall tree rows. For the purpose of increasing 

the water supply to wetlands, larger vegetative barriers 

such as tree rows may be unfavorable because they require 

a significant amount of time to get established, are more 

permanent than other snow barriers (Shaw, 1988), may 

consume water that would otherwise be available to the 

wetland (Siddoway, 1970; Greb and Black, 1961a), and 

may not be good ecological fits in natural grassland habitats 

(Kelsey and others, 2006). Grass strips provide a better option 

as a vegetative barrier for the purpose of trapping snow in 

wetland basins. Strips of sorghum (Sorghum bicolor; Greb and 

Black, 1961b), sudangrass (Sorghum x drummondii; Greb and 

others, 1965), tall wheatgrass (Thinopyron ponticum; Black 

and Siddoway, 1971), corn (Zea mays; Tabler, 1994), and other 

species have been used as vegetative barriers to trap snow. The 

method for creating a grass strip is similar for each species; a 

row or multiple rows of grass are planted perpendicular to the 

prevailing wind. This type of vegetative barrier can also be 

obtained by leaving strips in mowed or cultivated vegetative 

cover (Pomeroy and Gray, 1995). Reducing vegetation height 

and increasing surface roughness is effective for increasing 

snow movement and water yield on sagebrush rangelands. 

Snow accumulation was increased by mowing sagebrush on 

the windward side of a ridge (Sturges and Tabler, 1981). This 

allowed for more snow to be transported across the ridge and 

to become trapped on the leeward side. Sturges and Tabler 

(1981) estimated that this method could provide an average 

of 63 percent of the water needed to fill a 12,200-cubic-meter 

stock pond; however, most of the water was lost to seepage 

and did not reach the intended stock pond. Strips of crested 

wheatgrass among sagebrush rangeland doubled on-site snow 

retention and improved site productivity by increasing surface 

roughness and trapping more snow (Sturges and Tabler, 1981). 

 When considering the design of a snow fence or 

vegetation barrier, height, porosity, and placement need to be 

considered. Whether using vegetation or artificial barriers, the 

principles are the same. To capture the largest drift possible, 

barriers should be placed perpendicular to the prevailing wind, 

and have a porosity of 40–60 percent. Artificial barriers should 

have a gap of 10–15 percent of the fence’s height at the bottom 

in order to keep the fence from becoming buried (Pomeroy 

and Gray, 1995). Snow barriers should also extend beyond the 

area of interest by at least 25 degrees Fahrenheit on both sides 

to account for drift loss because of end effects (Tabler and 

Schmidt, 1986).

The largest snowdrift that a barrier can sustain is referred 

to as the equilibrium drift. The length of a leeward equilibrium 

drift will be at maximum 35 times the barrier height with a 

maximum depth 1.2 times the barrier height (fig. 8). A snow 

barrier may also create a drift on the windward side of the 

fence. The windward equilibrium drift will have a length about 

15 times the barrier height with a maximum depth 0.5 times 

the barrier height (Pomeroy and Gray, 1995). The dimensions 

reported are for horizontal-slat fence designs with 50 percent 

porosity on level terrain; other snow barrier designs may 

have slightly different equilibrium drift dimensions. Also, 

topographic depressions already act as snow catchments; thus, 

adding a snow barrier will only enhance the amount of snow 

caught (Jairell and Schmidt, 1990; Tabler, 1975).

Barrier

1.2 times the 

barrier height

Barrier height

15 times the 

barrier height

Vertical scale is exaggerated

35 times the 

barrier height

Wind

Modified from Pomeroy and Gray, 1995

Figure 8. Equilibrium drift geometry for a horizontal slat fence with 50 percent porosity placed on level 

terrain.
Upland Management Effects on Prairie Pothole Wetland Hydrology 15

Research on snow barriers has primarily focused on 

increasing streamflow (Sturges, 1992; Tabler and Sturges, 

1986; Harrison, 1986; Cooley and others, 1981), increasing 

soil moisture (Ries and Power, 1981; Black and Siddoway, 

1971; Greb and Black, 1961b), and protecting highways from 

snowstorms and snow drifting (Tabler, 1973). Currently, 

there has been no research on the effects of snow fences on 

wetland water levels in the northern prairie region. However, 

some conclusions may be made from studies researching 

the effects of snow fences on livestock pond and irrigation 

reservoir water levels. When placed on the windward side of a 

channel that flowed into an irrigation reservoir, snow fencing 

increased water yield by an average of 54 cubic meters per 

year (Sturges and Tabler, 1981). Constructing snow fences 

on the windward side of livestock ponds greatly increased 

the volume of snow captured over the pond (Sturges, 1989). 

However, much of the water was unavailable to cattle during 

the grazing season because of large amounts of seepage. Thus, 

it is important to consider soil drainage class when trying to 

increase water input into livestock ponds and natural wetlands. 

Soil permeability rates should fall below the low end of the 

poor drainage class when trying to increase water levels for 

an extended period of time (Sturges, 1989). Snow fences 

were most effective when placed leeward of the pond with an 

embankment on the windward side of the pond (Jairell and 

Tabler, 1985). This configuration could produce 5.8 times 

more snow volume near the pond, whereas a configuration 

with both the snow fence and embankment located on the 

leeward side of the pond increased volume of snow by 5.6 

times (fig. 9).

Prairie pothole wetlands naturally catch snow because 

of their topography and vegetation (Fang and Pomeroy, 

2009; Tabler, 1975). Topography and vegetation alter surface 

roughness and redirect wind; thus, topography and vegetation 

affect snow distribution. For example, a leeward slope will 

accumulate much larger volumes of snow than the windward 

slope if vegetation is absent (Pomeroy and Gray, 1995; 

Steppuhn, 1981). Additionally, increases in surface roughness 

caused by vegetation manipulation increased the amount of 

snow captured on the landscape (Pomeroy and Gray, 1995; 

Steppuhn, 1981). Thus, tall wetland vegetation can act as 

a natural snow barrier. This effect could be enhanced by 

reducing surrounding upland vegetation height by grazing 

or burning. By reducing upland vegetation height, more 

snow will be free to be transported into wetland basins. 

Therefore, grazing and burning should not only affect a 

catchment’s hydrology in terms of runoff events, but also how 

the catchment will capture snow. In fact, for farmers in the 

northern plains to burn off wetland vegetation in the fall so the 

vegetation will not catch blowing snow is common practice. 

This reduces the amount of flooding in a farmer’s field and 

may even allow for the wetland basin to be cultivated if 

conditions are dry enough.

Wetland water levels are affected by vegetation in 

the surrounding catchment. Water levels for 10 cultivated 

wetlands were monitored from 1968 to 1997 (van der Kamp 

and others, 1999). During 1980–83, five of the wetland 

catchments had been converted to smooth bromegrass and 

alfalfa cover, and the other five remained in cultivation. 

During 1968–80, water-level fluctuations were similar for all 

ten wetlands. However, during 1980–97 the water levels of 

the five wetlands that had their catchments converted began to 

drop and became dry after a few years, and the wetlands that 

remained in cultivation remained wet. The converted wetlands 

remained dry except when overland flow from other wetlands 

took place during periods of increased precipitation.

Possible mechanisms behind the drying of the wetlands 

with converted catchments were evaluated (van der Kamp and 

others, 2003). Snowmelt runoff was greatly reduced for the 

wetlands with catchments of smooth bromegrass and alfalfa. 

Under complete grass cover, snow was trapped in the uplands 

because of the standing grass, whereas snow in the cultivated 

fields was blown off the uplands and caught by the standing 

vegetation in the wetland basin. Also, snowmelt was more 

likely to infiltrate into the soil and be lost to evapotranspiration 

because of the grassed soil having a more developed 

macropore structure. Infiltrability of the frozen cultivated soil 

fell below the rate at which the snow melted, whereas the 

infiltrability of the frozen grassed soil was typically higher 

than the rate at which the snow melted. The data show that 

changes in land cover can greatly affect how a landscape 

captures snow and have significant impacts on the hydrology 

of wetlands within the landscape.

-18

-6

0

-6

0

6

6

-6

0

6

-12

Pond

Pond

Pond

Snow fence

Snow fence

Snow

Snow

Snow

Snow

Dike (embankment)

-6 0 6 12

Horizontal distance, in meters

18 24 30 36 42 45

Vertical distance, in meters

Pond upwind of dike

Snow fence on dike upwind of pond

Snow fence upwind of pond and dike

Snow

Snow

Dike (embankment)

Dike (embankment)

Modified from Jairell and Schmidt, 1990

Figure 9. Cross section of 1:30 model livestock pond.
16 Climate Change and Prairie Pothole Wetlands—Mitigating Water-Level and Hydroperiod Effects Through Upland Management

Conclusions

In addition to supporting a variety of wildlife, Prairie 

Pothole Region (PPR) wetlands provide other benefits to 

society that include water-quality improvement, flood control, 

groundwater recharge, carbon sequestration, recreation, and 

aesthetics. Despite the multiple benefits of having properly 

functioning wetlands on the landscape, many wetlands in the 

PPR have been filled, drained, or destroyed to facilitate crop 

production. Remaining wetlands are being affected from the 

cumulative effects of hydrologic and land-use alterations 

within watersheds. How the region’s remaining wetlands 

will respond to changing climate conditions resulting from 

increased levels of carbon dioxide in the atmosphere is of 

great concern.

Water conditions in PPR wetlands are sensitive to 

changes in climate because of the dependence of wetland 

water levels and hydroperiods on atmospheric interactions. 

Temperatures in the PPR are likely to increase between 

3.7 and 6.1 degrees Celsius (°C) by the end of the century. 

Increased temperatures will result in increased water 

losses from wetlands that correspond to increases in 

evapotranspiration and evaporative demand. Precipitation 

is harder to model because of its great regional variability. 

Nevertheless, future precipitation in the PPR is expected 

to increase by 10 percent and has already increased by an 

estimated 9 percent during the previous century. In addition 

to changes in average temperatures and precipitation, the 

frequency and severity of drought and deluge conditions, 

which are primary drivers of PPR wetland productivity, are 

expected to intensify under a climate affected by increased 

levels of atmospheric greenhouse gases.

Models of PPR wetlands under scenarios of climate 

change indicate that the wetlands will likely spend more time 

in a condition of low productivity when the wetlands are dry 

and (or) choked by stands of emergent cover. Temperature 

increases alone have potential to shift favorable water and 

vegetative cover conditions to the northern and eastern edges 

of the PPR. Increased precipitation in conjunction with 

temperature increases can have a counterbalancing effect, but 

only substantial increases in precipitation can ameliorate the 

effects of elevated temperatures. Model simulations indicate 

that a 5–7 percent precipitation increase would be needed 

to counteract each 1 °C temperature increase. However, 

interpretation of studies exploring the effects of climate 

change on PPR wetlands water dynamics are complicated 

by great spatial and temporal variation in wetland dynamics 

across the region. Even so, development of mitigation 

strategies that would deal with potential negative effects 

resulting from a changing climate would seem highly 

prudent.

Studies of grassland management effects on water 

runoff, infiltration, and snow accumulation indicated that 

the effects of climate change might be mitigated through 

the targeted use of land-use practices. Grazing by livestock 

can cause changes in the hydrology of a watershed through 

the removal of plant cover and the physical action of 

animal hooves on vegetation and soils. By altering runoff, 

infiltration, and upland evapotranspiration rates, grazing can 

have a significant effect on prairie pothole wetland water 

levels and hydroperiods. Prescribed burning can also cause 

an increase in runoff volume by decreasing infiltration, and 

prescribed burning on slopes less than 20 percent may not 

significantly increase erosion. Model runs indicate that spring 

burns can increase average annual water levels by about 

20 percent compared to the unmanaged native grasslands 

(Voldseth and others, 2007).

Snowmelt is the most crucial water supply for prairie 

pothole wetlands, accounting for as much as 80–85 percent 

of the total surface runoff for prairie habitats (LaBaugh and 

others, 1998). Snow is transported across the landscape 

by wind action until it forms drifts because of vegetation, 

topography, or manmade barriers. Snow accumulation can 

be managed with the use of manmade or vegetative barriers. 

Prairie pothole wetlands naturally catch snow because of 

the wetland topography and vegetation. Topography and 

vegetation alter surface roughness and redirect wind, and thus 

affect snow distribution. Increases in surface roughness caused 

by vegetation manipulation can increase the amount of snow 

captured on the landscape. Thus, tall wetland vegetation can 

act as a natural snow barrier. Reducing surrounding upland 

vegetation using grazing or burning could enhance this snow 

capturing effect. By reducing the upland vegetation, more 

snow will be free to be transported into wetland basins. 

Therefore, grazing and burning should not only affect a 

catchments hydrology in terms of runoff events but also how 

the catchment will capture snow.

Future effects of a changing climate on prairie pothole 

wetland water levels and hydroperiods can be difficult to 

quantify because of naturally high variability of the region’s 

climate and ecosystems. However, upland management 

appears to indicate significant opportunities to mitigate 

potential effects. Grassland management can greatly 

affect how water infiltrates into soils, runs off following 

precipitation events, evaporates into the atmosphere, and 

distributes across the landscape during the winter. Thus, 

well planned and implemented grazing, burning, and snow 

management programs that focused on increasing water 

inputs to wetlands have great potential to mitigate some 

of the effects of a warming climate. The ability to target 

management actions to increase water inputs into wetlands 

will be especially important in areas where increases in 

precipitation are not enough to counteract the effects of 

increased evapotranspiration and thereby maintain water 

conditions in wetlands at desired levels. To further the 

ability to take advantage of mitigation opportunities, 

additional research is needed that focuses on refining upland 

management for the betterment of upland plant and animal 

communities and also the embedded wetland ecosystems. 

Additionally, more research is needed that focuses on 

verifying the model results and research conclusions 

discussed in this report.
References Cited 17

References Cited

Badh, A., Akyuz, A., Vocke, G., and Mullins, B., 2009, Impact 

of climate change on the growing seasons in select cities 

of North Dakota, United States of America: International 

Journal of Climate Change, Impacts and Responses, v. 1, 

p. 105–117.

Ballard, T., Seager, R., Smerdon, J., Cook, B., Ray, A.J., 

Rajagopalan, B., Kushnir, Y., Nakamura, J., and Henderson, 

N., 2014, Hydroclimate variability and change in the Prairie 

Pothole Region, the “Duck Factory” of North America: 

Earth Interactions, v. 18, p. 1–28.

Batt, B.D.J., Anderson, M.G., Anderson, C.D., and Caswell, 

F.D., 1989, The use of prairie potholes by North American 

ducks, in van der Valk, A.G., ed., Northern Prairie Wetlands: 

Ames, Iowa, Iowa State University Press, p. 204–227.

Benavides-Solorio, J., and MacDonald, L.H., 2001, Post-fire 

runoff and erosion from simulated rainfall on small plots, 

Colorado Front Range: Hydrological Processes, v. 15, 

p. 2931–2952.

Black, A.L., and Siddoway, F.H., 1971, Tall wheatgrass 

barriers for soil erosion control and water conservation: 

Journal of Soil and Water Conservation, v. 26, p. 107–111.

Blackburn, W.H., 1983, Livestock grazing impacts on 

watersheds: Rangelands, v. 5, p. 123–125.

Bremer, D.J., and Ham, J.M., 1999, Effect of spring burning 

on the surface energy balance in a tallgrass prairie: 

Agricultural and Forest Meteorology, v. 97, p. 43–54.

Bremer, D.J., Auen, L.M., Ham, J.M., and Owensby, C.E., 

2001, Evapotranspiration in a prairie ecosystem—Effects of 

grazing by cattle: Agronomy Journal, v. 93, p. 338–348.

Chanasyk, D.S., Mapfumo, E., and Willms, W., 2003, 

Quantification and simulation of surface runoff from fescue 

grassland watersheds: Agricultural Water Management, 

v. 59, p. 137–153.

Cooley, K.R., Huber, A.L., Robertson, D.C., and Zuzel, J.F., 

1981, Effects of snowdrift management on rangeland 

runoff, in Annual Western Snow Conference, 49th, St. 

George, Utah, 1981, Proceedings: St. George, Utah, Western 

Snow Conference, p. 55–64.

Conly, F.M., and Van der Kamp, G., 2001, Monitoring the 

hydrology of Canadian prairie wetlands to detect the effects 

of climate change and land use changes: Environmental 

Monitoring and Assessment, v. 67, 195–215.

Covich, A.P., Fritz, S.C., Lamb, P.J., Marzolf, R.D., Matthews, 

W.J., Poiani, K.A., Prepas, E.E., Richman, M.B., and 

Winter, T.C., 1997, Potential effects of climate change on 

aquatic ecosystems of the Great Plains of North America: 

Hydrological Processes, v. 11, p. 993–1021.

Dahl, T.E., 1990, Wetlands losses in the United States 1780’s 

to 1980’s: Washington, D.C., U.S. Fish and Wildlife 

Service, 13 p.

Dahl, T.E., 2014, Status and trends of prairie wetlands in the 

United States 1997 to 2009: Washington, D.C., U.S. Fish 

and Wildlife Service, 67 p.

DeBano, L.F., 2000, The role of fire and soil heating on water 

repellency in wildland environments–A review, Journal of 

Hydrology, v. 231, p. 195–206.

DeBano, L.F., Neary, D.G., and Ffolliott, P.F., 1998, Fire’s 

effects on ecosystems: New York, John Wiley & Sons, Inc.

Dyke, A.S., and Prest, V.K., 1987, Late Wisconsinan and 

Holocene history of the Laurentide ice sheet: Geographie 

Physique et Quaternaire, v. 41, p. 237–264.

Euliss, N.H., Jr., and Smith, L.M., 2010, Ecosystem process 

and the hemi-marsh concept—Clarifying principles for 

wetland management: National Wetlands Newsletter, v. 32, 

p. 23–24.

Euliss, N.H., Jr., Wrubleski, D.A., and Mushet, D.M., 1999, 

Wetlands of the prairie pothole region–Invertebrate species 

composition, ecology, and management, in Batzer, D., 

Rader, R.B., and Wissinger, S.A., eds., 1999, Invertebrates 

in freshwater wetlands of North America—Ecology and 

Management: New York, John Wiley and Sons, Inc., 

p. 471–514.

Ffolliott, P.F., and Thorud, D.B., 1977, Water yield 

improvement by vegetation management: Journal of the 

American Water Resources Association, v. 13, p. 563–571.

Frank, D.A., and Inouye, R.S., 1994, Temporal variation 

in actual evapotranspiration of terrestrial ecosystems—

Patterns and ecological implications: Journal of 

Biogeography, v. 21, p. 401–411.

Garbrecht, J.D., and Rossel, F.E., 2002, Decade-scale 

precipitation increase in Great Plains at the end of 20th 

century: Journal of Hydrologic Engineering, v. 7, p. 64–75.

Gleason, R.A., Laubhan, M.K., and Euliss, N.H., Jr., eds., 

2008, Ecosystem services derived from wetland conservation programs in the United States prairie pothole region 

with an emphasis on the U.S. Department of Agriculture 

Conservation Reserve and Wetlands Reserve Programs: 

U.S. Geological Survey Professional Paper 1745, 58 p.
18 Climate Change and Prairie Pothole Wetlands—Mitigating Water-Level and Hydroperiod Effects Through Upland Management

Gray, D.M., and Landine, P.G., 1988, An energy-budget 

snowmelt model for the Canadian Prairies: Canadian 

Journal of Earth Sciences, v. 25, p. 1292–1303.

Gray, D.M., Norum, D.I., and Dyck, G.E., 1970, Densities of 

prairie snowpacks, in Annual Western Snow Conference, 

38th, Victoria, British Columbia, 1970, Proceedings: 

Victoria, British Columbia, Western Snow Conference, 

p. 24–30.

Greb, B.W., and Black, A.L., 1961a, Effects of windbreak 

plantings on adjacent crops: Journal of Soil and Water 

Conservation, v. 16, p. 223–227.

Greb, B.W., and Black, A.L., 1961b, New strip cropping 

pattern saves moisture for dryland: Crops and Soils, v. 13, 

p. 23.

Greb, B.W., Mickelson, R.H., and Hinze, G.O., 1965, 

Conservation research at the Central Great Plains 

Field Station: Northern Plains Branch, Soil and Water 

Conservation Research Division, Agricultural Research 

Service, U.S. Department of Agriculture, misc. leaflet.

Hanson, C.L., Kuhlman, A.R., Erickson, C.J., and Lewis, J.K., 

1970, Grazing effects on runoff and vegetation on western 

South Dakota rangeland: Journal of Range Management, 

v. 23, p. 418–420.

Hanson, C.L., and Lewis, J.K., 1978, Winter runoff and soil 

water storage as affected by range condition: Proceedings of 

the First International Rangeland Congress, Denver, Colo., 

p. 284–287.

Harrison, W., 1986, Effects of snow fences on the snowpack 

of a block mountain in Otago: Journal of Hydrology New 

Zealand, v. 25, p. 18–40.

Helvey, J.D., 1980, Effects of a north central Washington 

wildfire on runoff and sediment production: Journal of the 

American Water Resources Association, v. 16, p. 627–634.

Henny, C.J., Anderson, D.R., and Pospahala, R.S., 1972, 

Aerial Surveys of Waterfowl Production in North America, 

1955–71: U.S. Fish and Wildlife Service Special Scientific 

Report, Wildlife 160, 48 p.

Hester, J.W., Thurow, T.L., and Taylor, C.A., 1997, Hydrologic 

characteristics of vegetation types as effected by prescribed 

burning: Journal of Range Management, v. 50, p. 199–204.

Holecheck, J.L., 1981, Livestock grazing impacts on public 

lands—A viewpoint: Journal of Range Management, v. 34, 

p. 251–254.

Intergovernmental Panel on Climate Change, 2013, Climate 

Change 2013–The Physical Science Basis, in Stocker, T.F., 

Qin, D., Plattner, G.K., Tignor, M., Allen, S.K., Boschung, 

J., Nauels, A., Xia, Y., Bex, V., and Midgley, P.M., eds., 

Contribution of Working Group I to the fifth assessment 

report of the Intergovernmental Panel on Climate Change: 

Cambridge, United Kingdom, and New York, Cambridge 

University Press, 1535 p.

Jairell, R.L., and Schmidt, R.A., 1990, Snow fencing near 

pit reservoirs to improve water supplies, in Annual 

Western Snow Conference, 58th, Sacramento, Calif., 

1990, Proceedings: Sacramento, Calif., Western Snow 

Conference, p. 156–159.

Jairell, R.L., and Tabler, R.D., 1985, Model studies of 

snowdrifts formed by livestock shelters and pond 

embankments, in Annual Western Snow Conference, 53th, 

Boulder, Colo., 1985, Proceedings: Boulder, Colo., Western 

Snow Conference, p. 167–170.

Johnson, W.C., Boettcher, S.E., Poiani, K.A., and 

Guntenspergen, G., 2004, Influence of weather extremes 

on the water levels of glaciated prairie wetlands: Wetlands, 

v. 24, p. 385–398.

Johnson, W.C., Millett, B.V., Gilmanov, T., and Naugle, D.E., 

2005, Vulnerability of northern prairie wetlands to climate 

change: BioScience, v. 55, p. 863–872.

Johnson, W.C., Werner, B., Guntenspergen, G.R., 

Voldseth, R.A., Millett, B., Naugle, D.E., Tulbure, M., 

Carroll, W.H., Tracy, J., and Olawsky, C., 2010, Prairie 

wetland complexes as landscape functional units in a 

changing climate: BioScience, v. 60, p. 128–140.

Kantrud, H.A., Krapu, G.L., and Swanson, G.A., 1989, 

Prairie basin wetlands of the Dakotas—A community 

profile: Washington, D.C., U.S. Fish and Wildlife Service 

Biological Report 85, 111 p.

Kelsey, K.W., Naugle, D.E., Higgins, K.F., and Bakker, K.K., 

2006, Planting trees in prairie landscapes—Do the 

ecological costs outweigh the benefits: Natural Areas 

Journal, v. 26, p. 254–260.

Knutsen, G.A., and Euliss, N.H., 2001, Wetland restoration in 

the prairie pothole region of North America—A literature 

review: U.S. Geological Survey, Biological Resources 

Division, Biological Science Report, USGS/BRD/BSR2001-0006, 54 p.

Koelliker, J.K., and Duell, A.B., 1990, Effect of burning on 

surface hydrology of tallgrass prairie, in Winter Meeting, 

Chicago, Ill., 1990, Proceedings: Chicago, Ill., American 

Society of Agricultural Engineers, Paper no. 902568, 11 p.
References Cited 19

LaBaugh, J.W., Winter, T.C., and Rosenberry, D.O., 1998, 

Hydrologic functions of prairie wetlands: Great Plains 

Research, v. 8, p. 17–37.

Larson, D.L., 1995, Effects of climate on numbers of northern 

prairie wetlands: Climatic Change, v. 30, p. 169–180.

Leitch, J.A., 1989, Politicoeconomic overview of prairie 

potholes, in van der Valk, A.G., ed., Northern Prairie 

Wetlands: Ames, Iowa, Iowa State University Press, 

p. 2–14.

Leitch, J.A., 1996, Empirical valuation of prairie potholes—

Five case studies: Great Plains Research, v. 6, p. 25–39.

Manabe, S., and Wetherald, R.T., 1987, Large-scale changes 

of soil wetness induced by an increase in atmospheric 

carbon dioxide: Journal of the Atmospheric Sciences, v. 44, 

p. 1211–1236.

Meehl, G.A., Tebaldi, C., and Nychka, D., 2004, Changes in 

frost days in simulations of twentyfirst century climate: 

Climate Dynamics, v. 23, p. 495–511.

Millett, B., Johnson, W.C., and Guntenspergen, G., 2009, 

Climate trends of the North American prairie pothole region 

1906–2000: Climatic Change, v. 93, p. 243–267.

Murphy, J.M., and Mitchell, J.F.B., 1995, Transient 

response of the Hadley centre coupled ocean-atmosphere 

to increasing carbon dioxide: Journal of Climate, v. 8, 

p. 36–80.

Naeth, M.A., and Chanasyk, D.S., 1996, Runoff and sediment 

yield under grazing in foothills fescue grasslands of Alberta: 

Journal of the American Water Resources Association, v. 32, 

p. 89–95.

Neary, D.G., 1995, Effects of fire on water resources—A 

review: Hydrology and Water Resources in Arizona and the 

Southwest, v. 22–25, p. 45–53.

Niemuth, N.D., Fleming, K.K., and Reynolds, R.E., 2014, 

Waterfowl conservation in the US Prairie Pothole Region—

Confronting the complexities of climate change: Public 

Library of Science One, v. 9, e100034.

Niemuth, N.D., Wangler, B., and Reynolds, R.E., 2010, 

Spatial and temporal variation in wet area of wetlands in the 

Prairie Pothole Region of North Dakota and South Dakota: 

Wetlands, v. 30, p. 1053–1064.

Ojima, D.S., Lackett, J.M., and the Central Great Plains 

Steering Committee and Assessment Team, 2002, Preparing 

for a changing climate—The potential consequences of 

climate variability and change, Central Great Plains: Report 

for the U.S. Global Change Research Program, Colorado 

State University, 103 p.

Ouyang, Z., Becker, R., Shaver, W., and Chen, J., 2014, 

Evaluating the sensitivity of wetlands to climate change 

with remote sensing techniques: Hydrological Processes, 

v. 28, p. 1703–1712.

Palmer, W.C., 1965, Meteorological drought: U.S. Weather 

Bureau, Research Paper 45, 58 p.

Poiani, K.A., and Johnson, W.C., 1991, Global warming and 

prairie wetlands: BioScience, v. 41, p. 611–618.

Poiani, K.A., and Johnson, W.C., 1993a, A spatial simulation 

model of hydrology and vegetation dynamics in semipermanent prairie wetlands: Ecological Applications, v. 3, 

p. 279–293.

Poiani, K.A., and Johnson, W.C., 1993b, Potential effects 

of climate change on a semi-permanent prairie wetland: 

Climatic Change, v. 24, p. 213–232.

Poiani, K.A., Johnson, W.C., and Kittel, T.G.F., 1995, 

Sensitivity of a prairie wetland to increased temperature and 

seasonal precipitation changes: Water Resources Bulletin, 

v. 31, p. 283–294.

Poiani, K.A., Johnson, W.C., Swanson, G.A., and Winter, 

T.C., 1996, Climate change and northern prairie wetlands—

Simulations of long-term dynamics: Limnology and 

Oceanography, v. 41, p. 871–881.

Pomeroy, J.W., and Gray, D.M., 1995, Snowcover 

accumulation, relocation, and management: Saskatoon, 

Canada, National Hydrology Research Institute Science 

Report No. 7, 144 p.

Ries, R.E., and Power, J.F., 1981, Increased soil water storage 

and herbage production from snow catch in North Dakota: 

Journal of Range Management, v. 34, p. 485–488.

Robichaud, P.R., and Waldrop, T.A., 1994, A comparison of 

surface runoff and sediment yields from low- and highseverity site preparation burns: Journal of the American 

Water Resources Association, v. 30, p. 27–34.

Shaw, D.L., 1988, The design and use of living snow fences in 

North America: Agriculture, Ecosystems and Environment, 

v. 22, p. 351–362.

Shjeflo, J.B., 1968, Evapotranspiration and the water budget 

of prairie pothole in North Dakota: U.S. Geological Survey 

Professional Paper 585–B, 49 p.

Siddoway, F.H., 1970, Barriers for moisture conservation and 

wind erosion control in the Great Plains: Journal of Soil and 

Water Conservation, v. 25, p. 180–184.

Smith, A.G., Stoudt, J.H., and Gallop, J.B., 1964, Prairie 

potholes and marshes, in J.P. Linduska, ed., Waterfowl 

Tomorrow: U.S. Government Printing Office, Washington, 

D.C., p. 39–50.
20 Climate Change and Prairie Pothole Wetlands—Mitigating Water-Level and Hydroperiod Effects Through Upland Management

Sorenson, L.G., Goldberg, R., Root, T.L., and Anderson, M.G., 

1998, Potential effects of global warming on waterfowl 

populations breeding in the Northern Great Plains: Climatic 

Change, v. 40, p. 343–369.

Steppuhn, H., 1981, Snow and agriculture, in Gray, D.M., 

and Male, D.H., eds., Handbook of Snow—Principles, 

Processes, Management and Use: Ontario, Canada, 

Pergamon Press Canada Ltd., p. 60–125.

Stewart, R.E., and Kantrud, H.A., 1971, Classification of 

natural ponds and lakes in the glaciated prairie region: 

Washington, D.C., Bureau of Sport Fisheries and Wildlife, 

Resource Publication 92, 57 p.

Sturges, D.L., and Tabler, R.D., 1981, Management of blowing 

snow on sagebrush rangelands: Journal of Soil and Water 

Conservation, v. 36, p. 287–292.

Sturges, D.L., 1989, Evaporation and seepage from a livestock 

reservoir equipped with a snow fence for water recharge, 

in Annual Western Snow Conference, 57th, Fort Collins, 

Colo., 1989, Proceedings: Fort Collins, Colo., Western 

Snow Conference, p. 9–20.

Sturges, D.L., 1992, Streamflow and sediment transport 

responses to snow fencing a rangeland watershed: Water 

Resources Research, v. 28, p. 1347–1356.

Swanson, G.A., Euliss, N.H., Hanson, B.A., and Mushet, 

D.M., 2003, Dynamics of a prairie pothole wetland 

complex—Implication for wetland management, in

Winter T.C., ed., Hydrological, Chemical, and Biological 

Characteristics of a Prairie Pothole Wetland Complex under 

Highly Variable Climate Conditions—The Cottonwood 

Lake Area, East-Central North Dakota: U.S. Geological 

Survey Professional Paper 1675, p. 55–94.

Tabler, R.D., 1973, New snow fence design controls 

drifts, improves visibility, reduces road ice, in Annual 

Transportation Engineering Conference, 46th, Denver, 

Colo., 1973, Proceedings: Denver, Colo., University of 

Colorado, p. 16–27.

Tabler, R.D., 1975, Predicting profiles of snowdrifts in 

topographic catchments, in Annual Western Snow 

Conference, 43rd, Coronado, Calif., 1975, Proceedings: 

Coronado, Calif., Western Snow Conference, p. 87–97.

Tabler, R.D., 1991, Snow fence guide: Washington, D.C., 

Strategic Highway Research Program, National Research 

Council, No. SHRP-W/FR-91-106, 61 p.

Tabler, R.D., 1994, Design guidelines for the control of 

blowing and drifting snow: Washington, D.C., Strategic 

Highway Research Program, National Research Council, 

No. SHRP-H-381, 364 p.

Tabler, R.D., and Schmidt, R.A., 1986, Snow erosion, 

transport, and deposition in relation to agriculture: 

Proceedings of the Symposium on Snow Management for 

Agriculture, Great Plains Agricultural Council Publication 

No. 120, p. 12–58.

Tabler, R.D., and Sturges, D.L., 1986, Watershed test of a 

snow fence to increase streamflow—Preliminary results: 

Proceedings of the Cold Regions Hydrology Symposium,

v. TPS-86-1, p. 53–61.

Tiner, R.W., 1984, Wetlands of the United States—Current 

status and recent trends: Washington, D.C., U.S. Fish and 

Wildlife Service, 59 p.

Tiner, R.W., 2003, Geographically isolated wetlands of the 

United States: Wetlands, v. 23, p. 494–516.

Turner, B.C., Hochbaum, G.S., Caswell, F.D., and 

Nieman, D.J., 1987, Agricultural impacts on wetland 

habitats on the Canadian Prairies: Transactions of the North 

American Wildlife and Natural Resources Conference, 

v. 52, p. 206–215.

van der Kamp, G.W., Stolte, W.J., and Clark, R.G., 1999, 

Drying out of small prairie wetlands after conversion of 

their catchments from cultivation to permanent brome grass: 

Hydrological Sciences Journal, v. 44, p. 387–397.

van der Kamp, G.W., Hayashi, M., Gallén, D., 2003, 

Comparing the hydrology of grassed and cultivated 

catchments in the semi-arid Canadian prairies: Hydrological 

Processes, v. 17, p. 559–575.

van der Valk, A.G., and Davis, C.B., 1978, The role of seed 

banks in the vegetation dynamics of prairie glacial marshes: 

Ecology, v. 59, p. 322–335.

Voldseth, R.A., Johnson, W.C., Gilmanov, T., Guntenspergen, 

G.R., and Millett, B.V., 2007, Model estimation of landuse effects on water levels of Northern Prairie wetlands: 

Ecological Applications, v. 17, p. 527–540.

Voldseth, R.A., Johnson, W.C., Guntenspergen, G.R., 

Gilmanov, G.R., and Millett, B.V., 2009, Adaptation of 

farming practices could buffer effects of climate change on 

northern prairie wetlands: Wetlands, v. 29, p. 635–647.

Werner, B.A., Johnson, W.C., and Guntenspergen, G.R., 2013, 

Evidence for 20th century climate warming and wetland 

drying in the North American Prairie Pothole Region: 

Ecology and Evolution, v. 3, p. 3471–3482.

Wilen, B.O., and Bates, M.K., 1995, The U.S. Fish and 

Wildlife Service’s National Wetlands Inventory project: 

Vegetatio, v. 118, p. 153–169.
References Cited 21

Winter, T.C., 1989, Hydrologic studies of wetlands in the 

northern prairie, in van der Valk, A.G., ed., Northern 

Prairie Wetlands: Ames Iowa, Iowa State University Press, 

p. 16–54.

Winter, T.C., and Rosenberry, D.O., 1998, Hydrology of 

prairie pothole wetlands during drought and deluge—A 

17-year study of the Cottonwood Lake Wetland Complex 

in North Dakota in the perspective of longer term measure 

and proxy hydrological records: Climatic Change, v. 40, 

p. 189–209.

Wright, H.A., Churchill, F.M., and Stevens, C., 1976, Effect 

of prescribed burning on sediment, water yield, and water 

quality from dozed juniper lands in central Texas: Journal of 

Range Management, v. 29, p. 294–298.

Zhang, H., Huang, G.H., Wang, D., and Zhang, X., 2011, 

Uncertainty assessment of climate change impacts on the 

hydrology of small prairie wetlands: Journal of Hydrology, 

v. 396, p. 94–103.

Zhang, X., Vincent, L.A., Hogg, W.D., and Niitsoo A., 2000, 

Temperature and precipitation trends in Canada during the 

20th Century: Atmosphere-Ocean, v. 38, p. 395–429.

Publishing support provided by: 

Rolla and Sacramento Publishing Service Centers

For more information concerning this publication, contact:

Director, USGS Northern Prairie Wildlife Research Center

8711 37th Street Southeast

Jamestown, North Dakota 58401

(701) 253–5500

Or visit the Northern Prairie Wildlife Research Center Web site at:

http://npwrc.usgs.gov/
22 Climate Change and Prairie Pothole Wetlands—Mitigating Water-Level and Hydroperiod Effects Through Upland Management

ISSN 2328-031X (print)

ISSN 2328-0328 (online)

http://dx.doi.org/10.3133/sir20155004

Renton and others— Climate Change and Prairie Pothole Wetlands—Mitigating Water-Level and Hydroperiod Effects Through Upland Management—SIR 2015–5004

Printed on recycled paper