Information on nonbreeding waterbirds using created wetlands in the Central Appalachian region of the United States is limited. We compared waterbird communities of two managed wetlands, created in 2013 and 2001, in West Virginia. We observed 27 species of waterbirds. Species richness and diversity were generally similar between the wetlands, but species composition and use differed.
Wetlands provide an assortment of ecosystem services, such as flood control, nutrient cycling, water filtration, and pollution removal [
Wetlands within the migratory and wintering ranges of waterbird species are critical to conserve and sustain their populations. Waterbirds use coastal and inland wetlands as stopover sites during migration and as habitat to rest, feed, or overwinter [
Despite their many benefits, wetlands tend to conflict with competing land and resource development interests. Over the past 2 centuries, many wetlands have been destroyed, converted for agricultural purposes, developed, or manipulated for other human uses. From the 1780s to the 1980s, the conterminous United States lost 53% of its original wetlands [
Several studies have focused on wetland functions and communities within the Central Appalachian region. In West Virginia, Gingerich and Anderson [
In the summer of 2013, the West Virginia Division of Natural Resources (WVDNR) partnered with West Virginia University and AllStar Ecology LLC to create a mitigated wetland in the Pleasant Creek Wildlife Management Area (WMA), located in north-central West Virginia. The created wetland (hereafter referred to as PC2013) is one of few wetlands in West Virginia managed specifically for the benefit of migratory and wintering waterbirds (e.g., food-producing vegetation was planted and water levels are manipulated). The WVDNR’s primary goal was to develop the wetland for waterfowl use and for both consumptive and nonconsumptive waterfowl recreation. It is generally assumed that created wetlands will provide the same ecological services as a natural wetland, but it is not guaranteed, and wetland age may be a confounding factor [
Our study took place in the Pleasant Creek WMA, located in the Tygart Valley watershed of north-central West Virginia, USA (Figure
Location of Pleasant Creek Wildlife Management Area, WV. The shaded area at the border of Taylor and Barbour Counties represents the Pleasant Creek Wildlife Management Area, which is managed by the West Virginia Division of Natural Resources.
The Pleasant Creek WMA is located within the Appalachian Plateau physiographic province. The underlying rock in this region is sedimentary, and streams tend to be dendritic. The regional climate is generally considered to be humid continental, with humid summers and cool to cold winters. The average precipitation for this region falls between 381 and 442 cm, with temperatures ranging from −3.3 to 5.0°C in January and 19.4 to 24.4°C in July. Because of the area’s valley topography, dense fogs are a common occurrence. Cloudy skies are also frequent due to the damming of moisture from the Appalachian Mountains.
Prior to creation, PC2013 had been a maintained field dominated by
PC2013 is mostly bordered by forest, with the northern portion partly under tree and shrub cover (Figure
Aerial view of the wetland created in 2001 (PC2001) and the wetland created in 2013 (PC2013). PC2001 is outlined in yellow, while PC2013 is outlined in orange.
We conducted weekly surveys from November to March in 2013-2014 and 2014-2015. Each wetland was surveyed 2 or 4 times per week by 1-2 trained observers. We conducted half of the surveys during morning hours, beginning within 30 minutes of sunrise, and half of the surveys during the evening, ending within 30 minutes of sunset, as dawn and dusk are primary waterbird foraging hours [
The study was focused on waterbirds that were actively using the wetlands; therefore, we recorded only waterbirds observed in the wetland or within 10 m of the wetland’s boundary. The small size and accessibility of the wetlands allowed for total counts of waterbirds. Birds that flew over the wetlands but were not foraging or actively using the wetland were not included in the analyses. Additional data collected included the Julian date, times that the survey started and ended, air temperature, and percent ice cover (i.e., the percentage of wetland area covered by ice). Ice cover was tested as a possible explanatory factor for no waterbird detection during the winter surveys.
To analyze the data and assess the ability of PC2013 to provide waterbird habitat in comparison to the older PC2001, we compared overall, annual, and monthly waterbird species richness, diversity, composition, and use (dependent variables) at each wetland (independent variable). Because we could not confidently identify when individual waterbirds used the wetland multiple days, species use was quantified as the highest species count of each week’s surveys (e.g., if 2
Variation between wetlands was compared using overall metrics that were combined from the entire survey period. The means from the ANOVA tests were derived from monthly count data (e.g., overall species diversity for PC2001 was calculated using the monthly diversity values from November to March 2013-2014 and 2014-2015 data) and weekly high species counts (e.g., for comparing species use). Variation between wetlands by year was compared using annual metrics. Thus, the means from the ANOVA tests were derived from values from the monthly count data (e.g., annual species diversity for PC2001 in 2013-2014 was calculated using the diversity values from November 2013, December 2013, January 2014, February 2014, and March 2014) and weekly high species counts. Variation between wetlands by month was compared using average monthly metrics that were derived from the weekly surveys conducted within that month.
In addition, we examined trends in waterbird use by creating use curves (waterbirds/ha plotted against time) for waterbird species that comprised at least 2.0% of the species composition at either wetland during the 2 years of surveys. Monthly use was calculated by averaging the weekly high species counts and dividing by the number of hectares encompassed by the corresponding wetland. Average waterbird use per ha was plotted for each month in the study. The use curves allow us to determine when waterbirds are using the 2 wetlands and visualize in which months use is similar or diverges.
During November to March 2013-2014, we conducted 127 surveys and observed 1,831 waterbirds (
Combining the 2 years, a grand total of 248 surveys (124 surveys at each wetland) were conducted from November 2013 to March 2015, and 3,340 waterbirds (
Overall average species richness initially appeared higher at PC2001, but further analyses to compensate for the effects of wetland size revealed no significant difference (
Summary of overall and annual waterbird species use, richness, and diversity with their means and standard errors at 2 created wetlands (PC2001 and PC2013) in Pleasant Creek WMA, WV, from November to March 2013-2014 and 2014-2015. Individual and total species use was calculated using weekly high species counts per ha, while richness and diversity were calculated using total waterbird counts. Bolded means are significant following the use of the sequential Bonferroni approach. Italicized means indicate a result that was rendered insignificant after compensating for differences in wetland size.
Common name | PC2001 | PC2013 |
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2013-14 PC2001 | 2013-14 PC2013 |
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2014-15 PC2001 | 2014-15 PC2013 |
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Mean | SE | Mean | SE | Mean | SE | Mean | SE | Mean | SE | Mean | SE | ||||
American Black Duck | 0.032 | 0.02 | 0.185 | 0.15 | 0.313 | 0.026 | 0.01 | 0.000 | 0.00 | 0.066 | 0.038 | 0.03 | 0.362 | 0.29 | 0.274 |
American Coot | 0.100 | 0.03 | 0.007 | 0.01 | 0.003 | 0.053 | 0.02 | 0.015 | 0.02 | 0.146 | 0.145 | 0.05 | 0.000 | 0.00 | 0.009 |
American Wigeon | 0.019 | 0.01 | 0.000 | 0.00 | 0.156 | 0.026 | 0.03 | 0.000 | 0.00 | 0.323 | 0.013 | 0.01 | 0.000 | 0.00 | 0.155 |
Belted Kingfisher | 0.031 | 0.01 | 0.022 | 0.01 | 0.555 | 0.023 | 0.01 | 0.015 | 0.02 | 0.653 | 0.038 | 0.01 | 0.029 | 0.02 | 0.694 |
Bufflehead |
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0.416 | 0.19 | 0.000 | 0.00 | 0.034 | 0.303 | 0.11 | 0.029 | 0.03 | 0.024 |
Blue-Winged Teal | 0.016 | 0.01 | 0.000 | 0.00 | 0.055 | 0.023 | 0.01 | 0.000 | 0.00 | 0.102 | 0.009 | 0.01 | 0.000 | 0.00 | 0.323 |
Cackling Goose | 0.005 | 0.00 | 0.000 | 0.00 | 0.179 | 0.003 | 0.00 | 0.000 | 0.00 | 0.323 | 0.006 | 0.01 | 0.000 | 0.00 | 0.323 |
Canada Goose |
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1.217 | 0.41 | 0.182 | 0.06 | 0.018 | 1.051 | 0.35 | 0.174 | 0.06 | 0.017 |
Canvasback | 0.048 | 0.02 | 0.000 | 0.00 | 0.010 | 0.056 | 0.02 | 0.000 | 0.00 | 0.021 | 0.041 | 0.03 | 0.000 | 0.00 | 0.156 |
Common Merganser | 0.006 | 0.00 | 0.007 | 0.01 | 0.912 | — | — | — | — | — | 0.013 | 0.01 | 0.014 | 0.01 | 0.912 |
Gadwall |
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0.360 | 0.12 | 0.000 | 0.00 | 0.003 | 0.069 | 0.04 | 0.000 | 0.00 | 0.125 |
Great Egret | 0.003 | 0.00 | 0.000 | 0.00 | 0.320 | — | — | — | — | — | 0.006 | 0.01 | 0.000 | 0.00 | 0.323 |
Greater Scaup | 0.034 | 0.02 | 0.000 | 0.00 | 0.067 | 0.036 | 0.03 | 0.000 | 0.00 | 0.235 | 0.032 | 0.02 | 0.000 | 0.00 | 0.155 |
Great Blue Heron | 0.045 | 0.01 | 0.030 | 0.01 | 0.426 | 0.053 | 0.02 | 0.030 | 0.02 | 0.484 | 0.038 | 0.01 | 0.029 | 0.02 | 0.705 |
Green-Winged Teal | 0.019 | 0.01 | 0.000 | 0.00 | 0.106 | — | — | — | — | — | 0.038 | 0.02 | 0.000 | 0.00 | 0.103 |
Horned Grebe | 0.002 | 0.00 | 0.000 | 0.00 | 0.320 | 0.003 | 0.00 | 0.000 | 0.00 | 0.323 | — | — | — | — | — |
Hooded Merganser | 0.089 | 0.02 | 0.170 | 0.06 | 0.191 | 0.125 | 0.05 | 0.258 | 0.10 | 0.249 | 0.054 | 0.02 | 0.087 | 0.05 | 0.516 |
Lesser Scaup | 0.263 | 0.10 | 0.000 | 0.00 | 0.007 | 0.393 | 0.18 | 0.000 | 0.00 | 0.037 | 0.139 | 0.06 | 0.000 | 0.00 | 0.030 |
Lesser Yellowlegs | 0.005 | 0.00 | 0.000 | 0.00 | 0.320 | — | — | — | — | — | 0.009 | 0.01 | 0.000 | 0.00 | 0.323 |
Mallard | 0.155 | 0.03 | 0.415 | 0.17 | 0.135 | 0.122 | 0.04 | 0.152 | 0.10 | 0.781 | 0.186 | 0.05 | 0.667 | 0.31 | 0.136 |
Northern Pintail | 0.010 | 0.01 | 0.000 | 0.00 | 0.179 | 0.020 | 0.01 | 0.000 | 0.00 | 0.179 | — | — | — | — | — |
Pied-Billed Grebe | 0.090 | 0.02 | 0.015 | 0.01 | 0.005 | 0.063 | 0.03 | 0.000 | 0.00 | 0.020 | 0.117 | 0.04 | 0.030 | 0.02 | 0.074 |
Redhead | 0.008 | 0.01 | 0.000 | 0.00 | 0.226 | 0.013 | 0.01 | 0.000 | 0.00 | 0.323 | 0.003 | 0.00 | 0.000 | 0.00 | 0.323 |
Ring-Necked Duck | 0.537 | 0.19 | 0.000 | 0.00 | 0.006 | 0.614 | 0.28 | 0.000 | 0.00 | 0.033 | 0.464 | 0.27 | 0.000 | 0.00 | 0.089 |
Ruddy Duck | 0.007 | 0.00 | 0.000 | 0.00 | 0.041 | 0.010 | 0.01 | 0.000 | 0.00 | 0.076 | 0.003 | 0.00 | 0.000 | 0.00 | 0.323 |
Tundra Swan | 0.015 | 0.01 | 0.000 | 0.00 | 0.208 | 0.030 | 0.02 | 0.000 | 0.00 | 0.208 | — | — | — | — | — |
Wood Duck | 0.063 | 0.02 | 0.430 | 0.14 | 0.011 | 0.086 | 0.04 | 0.182 | 0.08 | 0.261 | 0.041 | 0.03 | 0.667 | 0.26 | 0.020 |
Total species use |
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3.770 | 0.90 | 0.833 | 0.19 | 0.003 | 2.818 | 0.81 | 2.087 | 0.65 | 0.483 |
Species richness |
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10.8 | 2.48 | 2.8 | 0.66 | 0.014 | 9.4 | 2.50 | 3.6 | 0.68 | 0.056 |
Species diversity | 1.441 | 0.18 | 0.831 | 0.13 | 0.013 | 1.448 | 0.29 | 0.771 | 0.22 | 0.10 | 1.435 | 0.25 | 0.890 | 0.15 | 0.099 |
Average total species use over the course of the 2 survey periods was higher at PC2001. Three of the 27 species had significant differences in use. Buffleheads,
Average species richness and average species diversity were not significantly different during either year (Table
There was no significant difference in average total species use between the 2 wetlands in either year (Table
Species richness was originally found to be significantly greater at PC2001 in November 2013 (PC2001:
Species composition varied between wetlands and among months (Tables
Summary of significant differences in monthly waterbird species percent composition at 2 created wetlands (PC2001 and PC2013) in Pleasant Creek WMA, WV, from November to March 2013-2014. All of the following results are significant following the use of the sequential Bonferroni approach.
Month | % composition overlap | Species | PC2001 | PC2013 |
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November 2013 | 2.7 | American Coot | 7.59 | 0.00 | 10.5 | <0.005 |
Bufflehead | 17.41 | 0.00 | 24.1 | <0.001 | ||
Canada Goose | 39.73 | 0.00 | 55.1 | <0.001 | ||
Gadwall | 8.48 | 0.00 | 11.8 | <0.001 | ||
Hooded Merganser | 2.68 | 100.0 | 117.5 | <0.001 | ||
Mallard | 6.70 | 0.00 | 9.3 | <0.005 | ||
Pied-Billed Grebe | 8.93 | 0.00 | 12.4 | <0.001 | ||
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December 2013 | 8.3 | Belted Kingfisher | 3.18 | 50.0 | 49.6 | <0.001 |
Gadwall | 76.43 | 0.00 | 106.0 | <0.001 | ||
Great Blue Heron | 5.10 | 50.0 | 42.4 | <0.001 | ||
Ruddy Duck | 3.18 | 0.00 | 11.5 | <0.001 | ||
Tundra Swan | 8.28 | 0.00 | 11.5 | <0.001 | ||
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January 2014 | 0.0 | American Coot | 0.00 | 11.11 | 15.4 | <0.001 |
Canada Goose | 87.37 | 0.00 | 121.1 | <0.001 | ||
Mallard | 0.00 | 66.67 | 92.4 | <0.001 | ||
Wood Duck | 0.00 | 22.22 | 30.8 | <0.001 | ||
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February 2014 | 54.5 | Bufflehead | 12.20 | 0.00 | 16.9 | <0.001 |
Hooded Merganser | 21.14 | 50.0 | 12.1 | <0.001 | ||
Mallard | 0.00 | 16.67 | 23.1 | <0.001 | ||
Ring-Necked Duck | 13.01 | 0.00 | 18.0 | <0.001 | ||
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March 2014 | 35.4 | Bufflehead | 11.91 | 0.00 | 16.5 | <0.001 |
Hooded Merganser | 1.04 | 18.52 | 19.0 | <0.001 | ||
Lesser Scaup | 15.83 | 0.00 | 21.9 | <0.001 | ||
Ring-Necked Duck | 25.74 | 0.00 | 35.7 | <0.001 | ||
Wood Duck | 2.00 | 27.78 | 26.6 | <0.001 |
Summary of significant differences in monthly waterbird species percent composition at 2 created wetlands (PC2001 and PC2013) in Pleasant Creek WMA, WV, from November to March 2014-2015. All of the following results are significant following the use of the sequential Bonferroni approach.
Month | % composition overlap | Species | PC2001 | PC2013 |
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November 2014 | 20.8 | American Coot | 16.67 | 0.00 | 23.1 | <0.001 |
Belted Kingfisher | 0.83 | 13.33 | 13.3 | <0.001 | ||
Mallard | 11.67 | 0.00 | 16.2 | <0.001 | ||
Pied-Billed Grebe | 45.0 | 13.33 | 18.2 | <0.001 | ||
Wood Duck | 0.00 | 60.00 | 83.2 | <0.001 | ||
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December 2014 | 12.8 | Canada Goose | 57.05 | 0.00 | 79.1 | <0.001 |
Mallard | 11.54 | 0.00 | 16.0 | <0.001 | ||
Wood Duck | 0.00 | 83.33 | 115.5 | <0.001 | ||
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January 2015 | 25.0 | Canada Goose | 66.04 | 0.00 | 91.6 | <0.001 |
Mallard | 75.00 | 0.00 | 104.0 | <0.001 | ||
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February 2015 | 63.0 | American Black Duck | 7.69 | 41.07 | 25.1 | <0.001 |
Hooded Merganser | 19.23 | 0.00 | 26.7 | <0.001 | ||
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March 2015 | 29.0 | American Coot | 6.50 | 0.00 | 9.0 | <0.005 |
Bufflehead | 12.16 | 0.00 | 16.9 | <0.001 | ||
Lesser Scaup | 7.34 | 0.00 | 10.2 | <0.005 | ||
Ring-Necked Duck | 23.17 | 0.00 | 32.1 | <0.001 | ||
Wood Duck | 2.20 | 53.20 | 58.3 | <0.001 |
Eleven waterbird species (American Black Duck, American Coot, Bufflehead, Canada Goose, Gadwall, Hooded Merganser, Lesser Scaup, Mallard, Pied-Billed Grebe, Ring-Necked Duck, and Wood Duck) comprised at least 2.0% at either wetland during the 2 years of surveys. Each species differed slightly in patterns of monthly use, which was calculated by averaging the weekly high counts. American Black Ducks, Mallards, Hooded Merganser, and Wood Ducks tended to have higher use at PC2013 (Figure
Average American Black Duck (a), Mallard (b), Hooded Merganser (c), and Wood Duck (d) use per ha at PC2001 and PC2013 from November to March 2013-2014 and 2014-2015.
American Coot and Pied-Billed Grebes had higher uses at PC2001 in November and March of both years (Figure
Average American Coot (a), Pied-Billed Grebe (b), Canada Goose (c), and Gadwall (d) use per ha at PC2001 and PC2013 from November to March 2013-2014 and 2014-2015.
Average diving duck (Lesser Scaup (a), Ring-Necked Duck (b), and Bufflehead (c)) use per ha at PC2001 and PC2013 from November to March 2013-2014 and 2014-2015.
To our knowledge, this was the first study to evaluate winter waterbird use of differently aged created wetlands in the Central Appalachians. Over the two 5-month periods during our study, we observed the wetlands harboring 3,340 waterbirds belonging to 27 species. They provided food and habitat to a diversity of migratory and wintering waterbirds, which in turn contributed to regional biodiversity and recreational hunting opportunities. At the wetland scale, winter waterbird species richness was not significantly different when wetland area was compensated for. Similarly, average species richness was not significantly different between the 2 wetlands in individual years, though both average species richness and diversity values for PC2013 increased slightly in the second winter, which may indicate that those metrics will increase over time. The greatest disparities in species richness and diversity tended to occur in November 2013, March 2013, and March 2014, while the least disparities occurred in January and February 2013 and 2014. These trends indicate that PC2013 may not attract as many waterbird species during migration (November and March) as PC2001.
The overlap in species composition ranged from 0% in January 2014 to 63% in February 2015, with an average of 25% across months. Differences in species composition were greatest from November to December 2013 and least in January and February 2015. Percent overlap increased or stayed similar in months from the first winter to the second winter. PC2001 generally had higher percent composition of American Coot, Bufflehead, Canada Goose, Gadwall, Lesser Scaup, and Ring-Necked Duck.
Certain waterbirds, including Buffleheads, Canada Geese, Gadwall, Lesser Scaup, and Ring-Necked Duck, tended to have higher use at PC2001. Differences in use were highest in March 2015. Average total species use tended to be higher at PC2001, though there was generally no statistical difference between the wetlands. The difference in total species use was less distinct in the second winter, which may indicate increased habitat availability or quality at PC2013 as the recently created wetland developed and matured. Because waterfowl exhibit site philopatry in the winter and are known to explore new sites, it is also possible that individuals that wintered at PC2013 the first year would come back again the next year and that additional individuals would discover the new wetland, increasing overall use and abundance [
Trends in waterbird use were variable. For many waterbirds, particularly diving ducks, use was highest in March during migration. With some exceptions, mid-winter waterbird use was limited. Based on the species richness, diversity, composition, and use results, it appears that the ability of PC2013 is similar to PC2001 in providing habitat for wintering waterbirds but not migrating waterbirds. Furthermore, PC2013 provides different habitat types that appear to favor a different winter waterbird community than PC2001, as its community composition tends to comprise Hooded Mergansers, Mallards, and Wood Ducks. For instance, American Black Ducks, Mallards, and Wood Ducks were observed using the stream within the PC2013 wetland complex when the wetland itself was covered in ice, and Wood Ducks were often found in the upper portion of the wetland, which is interspersed with trees and shrubs.
Certain disparities in species diversity, composition, and use might be explained by differences in wetland area, water depth, microtopography, and vegetative cover. Wetland size can predict waterbird richness and species abundance [
Water depth and microtopography also play a role in shaping waterbird communities. Many studies cite water depth as an important variable that affects waterbird use of wetland habitats [
Though we were unable to directly discern the effects of age on differences between the 2 wetlands, we can comment on possible indirect effects. As a wetland ages and matures, habitat availability or quality may increase. Wetland vegetation, another major factor that influences waterbird use of wetlands, can become established and flourish over time. Vegetation and habitat heterogeneity are related [
The results of our study were somewhat similar to other previously conducted in the region. Balcombe et al. [
However, studies evaluating created versus natural wetland function vary in their results. Outside of the Central Appalachian region, another study investigated avian communities in created and natural wetlands in Virginia. Desrochers et al. [
Similar to the findings of White and Main [
Our analyses were designed to quantify the differences and changes in the waterbird communities of 2 wetlands of different ages during 2 winter seasons. Though the results of this study are limited in direct applications to the development and management of PC2013, they provide insight into the potential impacts of newly created wetland habitat on local and migrant waterbird species in the Central Appalachians during the nonbreeding season. Our results further highlight important factors of wetland construction that must be taken into account. When designing and creating wetlands, it is important to consider management objectives, wetland size, water depth, topography, and vegetation. Wetland size and water depth influence habitat diversity and waterbird use [
The authors declare that there are no conflicts of interest regarding the publication of this paper.
The authors thank N. S. Goodman and M. L. McMurdy for assisting with field research. Funding and logistical support for this project were provided by the West Virginia Division of Natural Resources, AllStar Ecology LLC, and the Tygart Valley Conservation District. This is scientific article no. 3303 of the West Virginia University Agriculture and Forestry Experiment Station.