Open Water Habitats

Lakes and ponds with coldwater habitat include lakes with deep, well oxygenated, cold water that support naturally reproducing populations of coldwater fish species such as Eastern brook trout, bridle shiner, and slimy sculpin.  They also support beaver, otter, common loons, and many species of insects and aquatic plants. Coldwater Lakes and Ponds habitat also includes ponds at higher elevations which maintain cooler water temperatures despite their shallow depth. Although water quality in most lakes and ponds with coldwater habitat is relatively good, high levels of development along the shoreline and in the surrounding watersheds of some lakes may lead to issues, such as eutrophication. Habitat degradation from undersized stream crossings, pollution from run-off and untreated wastewater, and aquatic herbicide application are threats to this habitat. Eaton has 860 acres of Open Water habitat.

Warmwater Lakes and Ponds are defined by their inability to support coldwater fish species due to a lack of cold, well oxygenated water in the summer. Instead, warmwater lakes and ponds typically support warmwater species such as large and smallmouth bass, chain pickerel, and freshwater mussels. Fishing and wildlife viewing in and around the lakes and ponds is an important contribution to the state's economy.

Usually along the shoreline or in shallow areas of the lake, submerged aquatic vegetation provides critical spawning and nursery habitat for a number of fish species. Predators use aquatic vegetation as cover for ambushing prey. Turtles, amphibians, and fish feed on the abundant invertebrate species that are found among aquatic plants. In warmwater lakes and ponds with undeveloped shorelines, waterfowl and many terrestrial species will use the lake or pond as nesting or foraging habitat. Pollution from run-off, and untreated wastewater are major threats to lake and pond ecosystems. Conservation actions for this habitat include protecting important habitat features along shorelines with vegetated buffers.

Shorelines of lakes, ponds, and streams with extensive, mature forests along the shore are critical yet rare habitats. High quality shorelines are usually found in places undisturbed by buildings, roads, docks, lawns, or heavy recreational activity.  Native shrubs and trees growing along shorelines help protect the water from soil erosion, runoff, pesticides, chemicals, and excess nutrients. These pollutants kill fish, promote the growth of aquatic weeds, and muddy the water, all of which diminish the value of the lake, pond or river for homeowners, boaters, anglers, swimmers, and wildlife alike. 

The best shoreline habitat has large areas of diverse underwater vegetation such as coontail and bladderwort mixed with aquatic plants such as pickerelweed and yellow pond lily that grow in scattered stands. These plants provide cover for aquatic invertebrates such as snails and dragonfly larvae, which are in turn fed upon by fish and other predators. Filter-feeding freshwater mussels burrow in the fine silt trapped by aquatic plants. 

Coves and shallow areas with aquatic vegetation are used as nursery and spawning habitat for many fish. Sunfish spawn in circular depressions in shallow water and crayfish are abundant in rocky shallows. Dead trees in the water provide habitat for young and adult sunfish, and underwater branches serve as attachment sites for pickerel frog and green frog eggs. Partially submerged tree trunks make excellent sunning spots for painted turtles. 

Young fish, insects, and amphibians living in shoreline habitats attract hawks, herons, ducks, otter, mink, raccoons, and northern water snakes which all forage along shorelines. Land along shorelines is critical wildlife habitat. Loons need undisturbed shoreline for nesting at the water’s edge. Warbling vireos and song sparrows nest in the branches of shoreline trees and shrubs, and common mergansers use hollows in dead trees. 

Coldwater Rivers and Streams are defined by their ability to maintain cold water temperatures during the hot summer months. The presence of coldwater fish species, including brook trout and slimy sculpin, is often an indicator of coldwater river or stream habitat. Brook trout are rarely found in rivers or streams that exceed a mean temperature of 68°F during the months of July and August. Riffles, pools, meander bends, and undercut banks are common habitat features within coldwater rivers and streams, and provide habitat for slimy sculpin, burbot, and creeper and Eastern pearlshell, two species of freshwater mussel. Cold water river and stream habitat is declining as average air temperatures increase with climate change. The increased frequency of intense rainfall events associated with climate change, in these often flashy systems, leads to habitat degradation associated with elevated levels of erosion and sedimentation, especially at the intersection of roads, bridges, and other infrastructure. Actions to protect coldwater rivers and streams include improving habitat connectivity, reducing habitat degradation caused by stream crossings, and preventing development in riparian zones.

The map below shows open water habitat in Eaton.  Clicking on any water body will tell its type and if it is good habitat for the state threatened bridle shiner or the Eastern brook trout, a species of greatest conservation need in New Hampshire.  The fish on the map indicate places where a New Hampshire Fish and Game Fish Survey was conducted.  Clicking on these will show the year in which the survey was conducted if it is known and the fish found at that time.