Introduction
The Chicago region straddles an ecotone between eastern forest and western grassland. Paradoxically, although the metropolitan area is home to approximately 8.75 million people, some of the best remaining examples of natural habitat in the midwest have been set aside there. There are oak woodlands and savannas, beech-maple forests, prairies filled with wildflowers, a different color each summer month; marshes, red maple swamps, fens running with cold ground water, and even a few tamarak bogs.
These natural gems survived in part because of the vision of a handful of citizens in the early years of the 20th century, and in part because of the accidents of location and economics. More recent efforts by various federal, state, county, local, and non-profit conservation agencies have contributed significantly to land protection.
With a few exceptions, the remaining core natural areas are relatively small. Since large-scale ecological processes do not function well in a fragmented urban environment, restoration and management plays an important role. Active prairie restoration efforts date back to at least the 1970s at Fermilab, and more recently savanna and woodland restoration efforts have been aggressively initiated. Taking advantage of the large population base, many of these activities are carried out by trained volunteers.
Annotated List of Chicago Region Amphibians
The Chicago region includes parts of northeastern Illinois, northwestern Indiana, and extreme southeastern Wisconsin. The entire area was glaciated as recently as 12,000 years ago, and is characterized by gently rolling moraines, level lake plains, and in some places, numerous wetlands. Portions of the Indiana counties were once covered by extensive forests, and several eastern amphibian species are present. Oak savanna and woodland alternated with prairie and wetland openings over most of the rest of the region. In the southwestern part of the area more extensive prairies were common. Today the region supports over eight million people. Despite the urban sprawl, extensive networks of open space preserves have been set aside by county, local, state, and federal agencies. Although most of these preserves are relatively small, some are of excellent natural quality. Considerable habitat restoration activity is currently underway.Salamanders
Mudpuppy - Necturus maculosus. Fully aquatic; still common in Lake Michigan and Wolf Lake, formerly occurred in most major rivers and lakes. Regional status uncertain.
Western Lesser Siren - Siren intermedia. Fully aquatic; known only from the Indiana portion of the Kankakee drainage, with current records only from Jasper County.
Blue-spotted Salamander - Ambystoma laterale. Common in wooded portions of the region, especially in Cook and Lake Counties Illinois, and Porter and LaPorte Counties Indiana. Apparently absent west of the Fox River. Polyploid varieties occur in Indiana and at one Illinois locality.
Spotted Salamander - Ambystoma maculatum. Limited to the more heavily forested parts of the region. Still relatively common in northern LaPorte County and at a few Cook and Will County localities. Lake County Illinois populations have declined or disappeared.
Marbled Salamander - Ambystoma opacum. A handful of records from Porter and LaPorte Counties, Indiana, the most recent in 1953. Extensive searches of wooded land in the vicinity of the Smith (LaPorte County) locality in 1999 failed to locate this species. All of the Chicago region historical localities are within the snowbelt southeast of and within a few miles of Lake Michigan, and are widely disjunct from the main body of the range, located more than 150 miles to the south.
Smallmouth Salamander - Ambystoma texanum. Enters the southwest corner of the region via the Illinois River Valley. There is a recent report from southwestern Will County, and historical records from Grundy County and near Kankakee. In LaSalle County, the species is found in floodplain forest and breeds in oxbow ponds. This species is abundant in central Illinois, but is at the edge of its range in this region.
Tiger Salamander - Ambystoma tigrinum. This is the most widespread salamander in the Chicago region, with numerous records available for most counties. It is especially common in former savanna regions, although it is often overlooked because of secretive habits and a limited period of surface activity.
Eastern Newt - Notophthalmus viridescens. Newts occur sporadically in the Chicago region, with most records in the more extensive woodlands. Recent records are available for Cook, Lake, and DuPage Counties in Illinois, and Lake and Porter Counties in Indiana.
Southern Two-lined Salamander - Eurycea cirrigera. This species in limited to the Kankakee River valley in Will and Kankakee Counties, along small wooded streams or seeps in the vicinity of bedrock outcrops. It is relatively common in the few small areas where it occurs. The Chicago region populations are more than 100 miles disjunct from the main body of the range to the southeast.
Four-toed Salamander - Hemidactylium scutatum. Usually associated with forested fens or other seepage-fed wooded wetlands, this species is known from a handful of localities in Will, Porter, and LaPorte Counties. Historical records in northern Cook and southeastern Lake Counties, Illinois are old and apparently no longer exist.
Redback Salamander - Plethodon cinereus. This eastern forest species is extremely abundant in the beech-maple forests of Porter and LaPorte Counties, and presently occurs at least as far west as the West Creek drainage of Lake County Indiana. A few Cook County records are known, but except for a well documented Calumet City historical locality, these are of questionable validity.
Frogs and Toads
American Toad - Bufo americanus. This habitat generalist occurs at almost all sites inventoried in the region to date. It is known from every county, with the largest populations typically in relatively open uplands and along river floodplains.
Fowler's Toad - Bufo fowleri. A relatively common species in the Indiana Dunes area and south of the Kankakee River, but restricted to sand areas in this region. Old localities from the Waukegan sand area apparently have not survived.
Northern Cricket Frog - Acris crepitans. Once an abundant species throughout the region, cricket frogs disappeared from much of the upper midwest sometime in the 1970s. The original habitat consisted of sunlit banks of permanent streams, rivers, and ponds in prairie and savanna regions. A few populations persist in Cook, Will and Kane Counties Illinois and Lake County Indiana.
Cope's Gray Treefrog - Hyla chrysoscelis. Common in the oak savannas of the Fox River valley in Kane, McHenry, Lake, and Walworth Counties. The exact limits of the range are uncertain.
Eastern Gray Treefrog - Hyla versicolor. Relatively common in the Indiana counties, and known from Will, Cook, and DuPage Counties in Illinois. The distribution of the two cryptic tree frog species is the subject of ongoing studies.
Spring peeper - Pseudacris crucifer. This eastern species is widespread and abundant in the extensively wooded parts of northern Porter and LaPorte Counties. It is also known from the more extensive wooded groves and riparian areas in most of the Illinois and Wisconsin counties, but in many places those populations are isolated.
Western Chorus Frog - Pseudacris triseriata. This habitat generalist occurs in every county in the region, and at most inventoried preserves. It is especially abundant in former prairie and savanna areas. In heavily forested parts of the Indiana Counties populations are more widely scattered.
Plains Leopard Frog - Rana blairi. This grassland species barely enters the southwestern part of the Chicago region, with records from Will, Kankakee, and Grundy Counties. A series of juveniles collected in southwest Cook County may represent a release, since subsequent searches have not located the species there.
Bullfrog - Rana catesbeiana. This is possibly the only local frog which is more common today than in presettlement times. Permanent bodies of water, including rivers, lakes, and farm ponds, are inhabited.
Green Frog - Rana clamitans. Common throughout the region, and especially in the more heavily wooded eastern counties. Permanent streams, marshes, and ponds are utilized.
Pickerel Frog - Rana palustris. Probably always rare in the region, the current status of this species is uncertain. The only relatively recent valid reports are from Walworth County. Old historical records are available for McHenry, Kane, and Porter Counties. Graminoid fens and fast flowing streams with bordering dense vegetation are the preferred habitats.
Northern Leopard Frog - Rana pipiens. This is a relatively common frog in the Illinois and Wisconsin counties. Areas with dense herbaceous vegatation near marshes provide the best habitat, usually within former landscape-level savanna regions. In the Indiana counties observations are usually from the more open areas in the Kankakee drainage. In extensively forested parts of Indiana the species is generally rare.
Wood Frog - Rana sylvatica. Common in the beech-maple forests of northern Porter and LaPorte counties, where it is not unusual to see several per hour in the spring or fall; present in a few of the larger and better quality Illinois forests, but generally rare. The last report from Lake County Illinois was in 1987.
Chicago Region - Geographical Definition
For these species accounts, the Chicago Region includes Cook, DuPage, Grundy, Kane, Kankakee, Kendall, Lake, McHenry, and Will Counties, in Illinois; Lake, LaPorte, and Porter Counties in Indiana; and a very small portion of extreme southeastern Kenosha County, Wisconsin. Following the example of the excellent book on Connecticut amphibians and reptiles by Michael Klemens, I have sometimes included information on populations in areas adjacent to the region as defined above, especially for rare or peripheral species.This approximately coincides with that of Chicago Wilderness, but with slightly larger areas in Indiana - especially in LaPorte County, due to field experience there, and partially because it is difficult to provide thorough accounts of a few eastern forest species without it.
The area covered is smaller than that of Floyd Swink and Gerould Wilhelm in Plants of the Chicago Region, primarily because completion of thorough inventories in some of the outlying counties would have added several years to this project without much gain in information. The western counties of Boone and DeKalb are mostly agricultural, and little high-quality habitat survives; in Indiana, the several additional counties include some fascinating sand areas and eastern forests, but no additional species; and the Wisconsin counties have already been thoroughly described by Richard Vogt and more recently by Gary Casper.
About The Species Accounts
Inventory efforts carried out in the past 20 years as part of site acquisition and management have contributed a great deal to our knowledge of Chicago Region amphibians. Mostly these have been done by agency staff or consultants. In the past few years, large scale frog monitoring efforts have been initiated, and several hundred volunteers have been trained. Much useful and reliable information on birds comes from enthusiasts and advanced amateurs; I believe that it is possible, over time, to do the same for amphibians.This series of web-based amphibian species accounts is an attempt to compile basic information in one easy to access location. Much of the information I once passed along in person at training workshops is here. The emphasis is on habitat, distribution and status. Those areas were the weakness of most earlier published accounts, and as a result, they were the focus of much of my own work and that of some of my colleagues. Although these accounts are not intended to take the place of a good field guide, some very basic identification and life history information has been included at the request of individuals who reviewed early versions.
About the Author
My interest in amphibians began as a child. I remember watching tiger salamander larvae in fascination, when I was perhaps six years old. By the end of second grade I had devoured every book on the subject, including the first edition of Roger Conant's field guide, in the grade school library. A few years later Sam Barakat, several years older than me, taught me about local species and their habitat. We used bicycles to visit most of the north Cook County preserves, and begged rides from parents to reach as far afield as Indiana Dunes and Volo Bog, then (1971) accessed via a series of 1x12 inch planks laid end to end over the unstable substrate. After pursuing other interests through high school and college, I returned to the study of amphibians in 1983. My early research was in northern flatwoods communities of Lake County Illinois, gradually expanding out to include locations in every regional county. In 1985-86 I spent some time in the old-growth Douglas-fir forests of Mendocino County, California and then a brief interlude assisting Lynne Houck with salamander research at Highlands Biological Station in North Carolina, before eventually returning to Chicago. Since 1987 I have conducted formal site inventories or monitoring efforts for the Lake County Forest Preserve District, Lake Forest Open Lands, McHenry County Conservation District, Forest Preserve District of Will County, and U.S. Department of Energy (Fermilab). Since 1990, as a Senior Ecologist with TAMS Consultants (now part of Earth Tech) I designed and managed inventories of project sites ranging from a few to 18,000 acres in size, in Cook, Lake, Will, Kankakee, and Grundy Counties, Illinois, Lake and Porter Counties, Indiana, and a variety of national and international locations. My LaPorte County experience derived partially from participation in a USEPA/NIRPC led effort to map and characterize ADID wetlands, and included extensive field time with access to private property in the fall of 1999.
It is perhaps useful to point out that although I grew up in the Chicago region and have far more field experience there than anywhere else, my experiences elsewhere have influenced my viewpoint. Currently I reside in northern California, where State Parks routinely encompass tens of thousands of acres, and National Forests sprawl across multiple counties. Because I now live in a place where amphibians occur nearly continuously across large segments of the landscape, I have a very different view of the tiny fragments of habitat in the Midwest. I believe that many of the amphibians I saw only occasionally near Chicago were once much more widely distributed. While I applaud the successes of buffer area acquisition and restoration, I also recognize what has been lost. When the vast majority of the land has been drained, plowed, and paved, the ecological cost must be appalling. Here, in my current home, some of those battles are still being fought, and the future of large parts of the landscape remains undecided.
Contact kenmierzwa@w-and-k.com