Home Archived March 16, 2018

Upper Midwest Environmental Sciences Center

Farm ponds as critical habitats for native amphibians

Constructed farm ponds represent significant breeding, rearing, and overwintering habitat for amphibians in the Driftless Area Ecoregion of southeastern Minnesota, western Wisconsin, and northeastern Iowa, a landscape where natural wetlands are scarce. Despite intensive agricultural use adjacent to the ponds, these ponds harbor an abundance of frogs and toads. This region contains thousands of farm ponds constructed with cost-sharing dollars from the U.S. Department of Agriculture and the states.

Northern Leopard Frog (Photo by Allen Sheldon)

Study area in Houston and Winona counties, Minnesota

Western Chorus Frog (Photo by Allen Sheldon)

Northern Spring Peeper (Photo by Allen Sheldon)

Natural wetland (Photo by Melinda Knutson)

We studied constructed farm ponds and natural wetlands in southeastern Minnesota during spring and summer 2000 and 2001 (Figure 2). We collected amphibian and habitat data from 40 randomly selected ponds, 10 ponds in each of four surrounding land use classes: row crop agriculture, grazed grassland, ungrazed grassland, and natural wetlands.

Redbelly Snake (Photo by Joel Jahimiak)

Over the 2 years of the study, we identified 10 species of amphibians at the ponds (Figure 3) including the tiger salamander (Ambystoma triginum), American toad (Bufo americanus), eastern gray treefrog (Hyla versicolor), chorus frog (Pseudacris triseriata), spring peeper (Pseudacris crucifer), green frog (Rana clamitans), wood frog (Rana sylvatica), leopard frog (Rana pipiens), and pickerel frog (Rana palustris).

Wood Frog (photo by Allen Sheldon)
Blue Spotted Salamander (Photo by Allen Sheldon)

The primary functions of farm ponds are to prevent soil erosion and create wildlife habitat, yet no studies have been conducted to determine how the ponds benefit wildlife.

We asked the following questions:

  1. How are measures of amphibian individual, population, and community health associated with land uses surrounding the pond, such as row crops, grassland, and grazed grassland?
  2. Are measures of amphibian individual, population, and community health more associated with surrounding landscape features or within-pond characteristics? (Figure 1)
  3. What design features associated with a pond (size, depth, and vegetation) will maximize wildlife benefits?

Our goal was to identify farm management practices that lead to sustainable amphibian populations, high diversity, and low incidence of deformities. We are also developing a guide to the design, construction, and management of farm ponds for use by contractors, private landowners, and state or federal agencies

USGS Staff Shawn Weick and Landowner Art Thicke  (Photo by Joel Jahimiak)

Weather conditions during the 2000 field season were dry in May, followed by heavy rainfall in late May through July. In 2001, steady April and May rains led to wet conditions early in the season, followed by a summer drought. We were fortunate to be able to study the same 40 ponds in both seasons.

USGS intern Kara Vick (Photo by Sam Bourassa)

The blue-spotted salamander (Ambystoma laterale) was identified at a single natural wetland. We observed high abundances of the American toad, eastern gray treefrog, and green frog at many ponds.

Six species of snakes and two turtle species were observed at the ponds over the 2 years of the study (Figure 4). The common garter snake (Thamnophis sirtalis) was the most frequently encountered reptile (18 ponds), followed by painted turtles (Chrysemys picta) (11 ponds).

Common Garter Snake (Photo by Shane Jones)Painted Turtle (Photo by Josh Kapfer)Song Sparrow (Photo by Allen Sheldon)

One hundred species of birds were observed at the ponds (Figure 5). The song sparrow (Melospiza melodia) was the most frequently observed bird species (40 ponds), followed by the red-winged blackbird (Agelaius phoeniceus; 34 ponds), common yellowthroat (Geothlypis trichas; 30 ponds), and the American robin (Turdus migratorius; 25 ponds). For pictures of the bird species link to

Eighteen species of mammals were observed, with the raccoon (Procyon lotor) as the most commonly observed mammal (34 ponds), followed closely by the white-tailed deer (Odocoileus virginianus; 33 ponds; Figure 6). Five species of fish were identified from the ponds, with brook stickleback (Culaea inconstans) the most frequently observed (6 ponds; Figure 7). A wide variety of invertebrate taxa were observed in the ponds (Figure 8). Midge larvae (Order=Diptera), crawling water beetles (Order=Coleoptera), and water boatmen (Order=Hemiptera) were the most common invertebrate taxa observed. Our invertebrate sampling concentrated on potential amphibian larval predators and snails and was not a comprehensive inventory of all invertebrates in the ponds.

Fingernail Clams (Photo by Allen Sheldon)
Fishing Spider (Photo by Allen Sheldon)

Student Josh Kapfer and USGS Biologist Bill Richardson (Photo by Joel Jahimiak)

Water quality characteristics, such as water temperature, pH, dissolved oxygen concentration, conductivity, turbidity, chlorophyll-a, nitrogen (nitrate+nitrite), and total phosphorus, can directly (e.g., anoxia) and indirectly (e.g., food web effects, development of noxious algae, etc.) affect amphibian survival, growth, and reproduction; therefore, we monitored for these factors.
At each pond, we measured water clarity (turbidity, NTU), dissolved oxygen (DO, mg L-1), conductivity (mmhos cm-1), and water temperature (C), as well as total nitrogen (TN) and total phosphorus (TP) estimates (Table 1).



Leopard Frog Eggs  (Photo by Joel Jahimiak)

We obtained additional funding from the U.S. Geological Survey (USGS) Amphibian Research and Monitoring Initiative in June 2000 to expand the study to measure post-breeding habitat use by northern leopard frogs (Rana pipiens), a common species in our study. This work, "Effects of agricultural and urban land use on movement and habitat selection by northern leopard frogs (Rana pipiens)", involves radio-telemetry of Rana pipiens during the post-breeding stage of the life cycle around two farm ponds and an urban-edge marsh within the U.S. Fish and Wildlife Service Upper Mississippi River National Wildlife and Fish Refuge. The objective of the study is to determine how adult Rana pipiens use the landscape after leaving the breeding pond and how they respond to potential hazards such as roads, crop fields, and urban development.


Dr. Dan Sutherland, University of Wisconsin-La Crosse, identified Riberoiria (the parasite responsible for amphibian deformities elsewhere) at a few locations, but in low numbers. None of the individuals with Riberoiria were deformed. Water quality in the ponds ranged from clear, stream-fed ponds (natural wetlands) to nutrient-rich, stagnant waters. Initial examination of the data does not indicate large differences in amphibian species richness or abundance among the four types of surrounding land uses; the data analysis is ongoing.

USGS Staff Shawn Weick, USGS Director Chip Groat, USGS Staff Jeff Keay  (Photo by Joel Jahimiak)

USGS Staff Shawn Weick and Intern Kara Vick  (Photo by Joel Jahimiak)

Principal Investigators: Melinda Knutson, William Richardson, Brent Knights (Upper Midwest Environmental Sciences Center), Mark Sandheinrich, Dan Sutherland (University of Wisconsin-La Crosse), and Jeff Parmelee (Simpson College)

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USA.gov logo U.S. Department of the Interior | U.S. Geological Survey

URL: http://www.umesc.usgs.gov/amphibians/mknutson_5003869_overview.html
Page Contact Information: Contacting the Upper Midwest Environmental Sciences Center
Page Last Modified: February 11, 2011