Photo by Thomas Meyer
- WDNR
State Rank: S2 Global Rank: GNR what are these ranks?
Small lakes (<10Ac) with alkalinity of > 50 ppm and high pH.
The pH of hard bog lakes is at or slightly above neutral, due to groundwater influence. This mineral-rich environment commonly supports a genus of macroalgae called muskgrass (Chara spp.), which in turn supports diverse aquatic invertebrates. As the muskgrasses extract carbon dioxide from calcium bicarbonate, they produce calcium carbonate which precipitates on the lake bottom in the form of marl. Many muskgrass populations have a hard or crunchy texture due to the crusty layer of marl that often precipitates on the plant's surface. If nutrient levels get very high, eutrophication may occur, resulting in a muddy false bottom as the remains of poorly decomposed microscopic plants and animals accumulate. A quaking sedge mat (often Carex lasiocarpa) typically occupies the margins of the lake, providing a substrate for pioneering Sphagnum. If conditions allow (e.g., low lake levels during dry years), this sedge mat may advance into the lake and eventually transition to poor fen. Indicators of groundwater influence are present in the vegetation surrounding the lake, even during later successional stages of the bog mat. These include distinctive species such as white beak-rush (Rhynchospora alba), bogbean (Menyanthes trifoliata), pink-flowered orchids ((grass pink (Calopogon tuberosus), rose pogonia (Pogonia ophioglossoides)), dragon's-mouth (Arethusa bulbosa), and tamarack (Larix laricina). Associated fish species include central mudminnow, yellow perch, golden shiner, fathead minnow, northern redbelly dace, finescale dace, and brook stickleback.
The following Species of Greatest Conservation Need are listed according to their level of association with the Lake--Hard Bog natural community type, based on the findings in Wisconsin's 2015 Wildlife Action Plan.
Scores: 3 = high association, 2 = moderate association, and 1 = low association. See the key to association scores for complete definitions.
| Amphibians | Score | |
|---|---|---|
| Blanchard's Cricket Frog | Acris blanchardi | 3 |
| Mink Frog | Lithobates septentrionalis | 3 |
| Pickerel Frog | Lithobates palustris | 2 |
| Beetles | Score | |
|---|---|---|
| A Minute Moss Beetle | Ochthebius lineatus | 2 |
| Birds | Score | |
|---|---|---|
| Black Tern | Chlidonias niger | 2 |
| Common Goldeneye | Bucephala clangula | 2 |
| Common Tern | Sterna hirundo | 1 |
| Forster's Tern | Sterna forsteri | 1 |
| Red-necked Grebe | Podiceps grisegena | 1 |
| Caddisflies | Score | |
|---|---|---|
| A Giant Casemaker Caddisfly | Banksiola dossuaria | 2 |
| A Phryganeid Caddisfly | Beothukus complicatus | 2 |
| Dragonflies and damselflies | Score | |
|---|---|---|
| Lake Emerald | Somatochlora cingulata | 3 |
| Mottled Darner | Aeshna clepsydra | 3 |
| Pronghorn Clubtail | Gomphus graslinellus | 3 |
| Spatterdock Darner | Rhionaeschna mutata | 3 |
| Unicorn Clubtail | Arigomphus villosipes | 3 |
| Double-striped Bluet | Enallagma basidens | 2 |
| Slaty Skimmer | Libellula incesta | 2 |
| Spangled Skimmer | Libellula cyanea | 2 |
| Lilypad Forktail | Ischnura kellicotti | 1 |
| Painted Skimmer | Libellula semifasciata | 1 |
| Subarctic Darner | Aeshna subarctica | 1 |
| Fishes | Score | |
|---|---|---|
| Redfin Shiner | Lythrurus umbratilis | 1 |
| Mammals | Score | |
|---|---|---|
| Big Brown Bat | Eptesicus fuscus | 3 |
| Little Brown Bat | Myotis lucifugus | 3 |
| Northern Long-eared Bat | Myotis septentrionalis | 2 |
| Silver-haired Bat | Lasionycteris noctivagans | 2 |
| Tricolored Bat | Perimyotis subflavus | 1 |
| Water Shrew | Sorex palustris | 1 |
| Reptiles | Score | |
|---|---|---|
| Blanding's Turtle | Emydoidea blandingii | 3 |
| Eastern Ribbonsnake | Thamnophis sauritus | 3 |
| Wood Turtle | Glyptemys insculpta | 2 |
| Western Ribbonsnake | Thamnophis proximus | 1 |
Please see Section 2. Approach and Methods of the Wildlife Action Plan to learn how this information was developed.
The following Ecological Landscapes have the best opportunities to manage for Lake--Hard Bog, based on the Ecological Landscapes of Wisconsin Handbook.
| Ecological Landscape | Opportunity |
|---|---|
| Northwest Lowlands | Major |
| Central Sand Hills | Important |
| Forest Transition | Important |
| North Central Forest | Important |
| Northeast Sands | Important |
| Southeast Glacial Plains | Important |
| Central Lake Michigan Coastal | Present |
| Central Sand Plains | Present |
| Northern Highland | Present |
| Northern Lake Michigan Coastal | Present |
| Superior Coastal Plain | Present |
Major (3 on map)
A major opportunity for sustaining the natural community in the Ecological Landscape exists, either because many significant occurrences of the natural community have been recorded in the landscape or major restoration activities are likely to be successful maintaining the community's composition, structure, and ecological function over a longer period of time.
Important (2 on map)
Although the natural community does not occur extensively or commonly in the Ecological Landscape, one to several occurrences do occur and are important in sustaining the community in the state. In some cases, important opportunities may exist because the natural community may be restricted to just one or a few Ecological Landscapes within the state and there may be a lack of opportunities elsewhere.
Present (1 on map)
The natural community occurs in the Ecological Landscape, but better management opportunities appear to exist in other parts of the state.
Conservation actions respond to issues or threats, which adversely affect species of greatest conservation need (SGCN) or their habitats. Besides actions such as restoring wetlands or planting resilient tree species in northern communities, research, surveys and monitoring are also among conservation actions described in the WWAP because lack of information can threaten our ability to successfully preserve and care for natural resources.
Threats/issues and conservations actions for natural communities
Click to view a larger version. Please considering donating your photos to the Natural Heritage Conservation Program for educational uses. Photo use
Photo by Thomas Meyer.
Photo by Aaron Carlson.
Note: photos are provided to illustrate various examples of natural community types. A single photograph cannot represent the range of variability inherent in a given community type. Some of these photos explicitly illustrate unusual and distinctive community variants. The community photo galleries are a work in progress that we will expand and improve in the future.