Every year, as the sun grows stronger, and mud season emerges from the cold of winter, it's time to step outside, rub your eyes and take in the familiar sites and sounds of spring in Maine. Each spring treats us to a chorus of spring peepers, wood frogs and bullfrogs, and the cheerful "oak-a-lee" of red-winged blackbirds trilling atop velvety remnants of last year's cattails. It's a time to gather pussy willows and fiddleheads. Soon, blue flag iris will paint the landscape, and brightly colored dragonflies will soar through the air on shimmering wings. When the red maple leaves are as big as a squirrel's foot, it will be time to plant. We recognize these species as signs of spring and part of Maine's natural hertiage, but they have something else in common. They can all be found in wetlands. Spring is not the only season when wetlands are full of life, they actually support many species throughout the year.
According to the Federal Enviromental Protection Agency's Office of Wetlands, more than one third of the Unites States' threatened and endangered species live only in wetlands and nearly half use wetlands at some point in their lives. In Maine, some of the threatened species found in wetlands include, the Blanding's Turtle, the Ringed Boghaunter Dragonfly, the Sedge Wren, the Black Tern and the English Sundew. Just as different wetland types exist side by side, with no clear demarcation line, so it is that many plant and animal species can live in serveral different types of wetland habitats. General wetland species include, bullfrogs, turtles, blue herons, osprey, mink, beaver, deer, moose, showshoe hare, tamarack, winterberry, ferns, sedges, rushes and grasses. However, some species like only certain wetland types and depend on specific habitat to survive. A discussion of the flora and fauna of individual wetland type follows.
Tidal marshes provide vital habitat for clams, crabs and juvenille fish, as well as providing shelter and nesting sites for migratory waterfowl. Plant communities can include smoth cordgrass, spike grass and black grass.
Freshwater marshes are one of the most productive ecosystems on earth, sustaining a myriad of plant and wildlife communities. Lily pads, reeds and bulrushes provide habitat for red-wing black birds, great blue herons, otters and muskrats. Many species, including wood ducks, muskrat and swamp rose will only be found in inland marshes. Other common species found here are loons, snapping and painted turtles, woodpeckers, warblers and other songbirds, osprey, marsh wren and many types of dragonflies and damselflies.
Water loving grasses, sedges, rushes and wildflowers can be found in the highly fertile soils of wet meadows.
Grasses, sedges, rushes and wildflowers often cover these habitats. The Showy ladyslipper (Cypripedium reginae) is a unique plant that thrives in fens.
Bogs supports some of the most interesting plants in the U.S., including the carnivorous sundew, the northern pitcher plant, cotton grass, cranberry, blueberry, pine Laborador tea and tamarack. They also provide habitat for lots of animal species, like moose, deer, lynx, cranes, the sora rail and the great gray owl. The northern pitcher plant (Sarracenia purpurea) compensates for the lack of nutrients in bog soils by caputuring insects in its leaves and use bacteria to digest them.
Shrub swamps are dominated by woody vegetation such as buttonbush, willow, dogwood and swamp rose. Beaver and yellow warblers are found in shrub swamps.
Red maple, sugar maple, birch, white ash, alder, swamp rose and elderberry dominate the vegetation in forested swamps. They provide habitat for wood ducks, river otters, beaver, mink, fisher, the red-spotted newt, eastern wild turkey, barred owl, pileated, downy and hairy woodpeckers and the black-capped chickadee. Jack-in-the-pulpit (Arisaema triphyllum) can be found in deciduous forested swamps.
Vernal pools are critically important spawning ares for amphibians, such as the spotted salamander, the blue-spotted salamander and wood frogs. The freshwater crustacean, fairy shrimp, spend its entire lives in vernal pools and are found no place else. Waterstiders, mayfly larvae and fishfly can also be found in vernal pools.