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Welcome to the Rachel Carson National Wildlife Refuge. Founded in 1966, it was named after the legendary Rachel Carson. Established in order to protect valuable salt marsh and estruine habitat for migratory birds, it is part of a system of more than 500 national wildlife refuges. As a resident or visitor to southern Maine, you may see our Blue Goose signs at the edge of the woods or along a salt marsh. These salt marshes support the purpose of the refuge in a number of ways. But what exactly is a salt marsh? Salt marshes are grass dominated ecosystems that form where rivers meet the sea – some develop behind barrier islands like the Webhannet marsh, others along rivers like the Spurwink or York. While salt marshes support a number of beautiful but diminutive flowers, they are dominated by grasses that can tolerate being periodically flooded by salty tidal waters. The two most common grasses mark the two main areas of the marsh. Cordgrass grows at lower elevations in the low marsh and is flooded on most high tides. Salt hay grows at higher elevations in the high marsh and is flooded only on the largest spring tides of the month. Spring tides are associated with full and new moons. In Maine, in contrast to other areas of the US, only five to eight of these tides flood the high marsh in any given month. Tidal flooding – in just the right amounts -- brings moisture, nutrients, and dissolved oxygen. These all help the marsh plants to grow abundant leaves and robust roots. Roots and old leaves form the dark peat which protects our shores and provides homes for abundant wildlife. Perhaps you have seen some of them. Ribbed mussels, American black ducks, mummichogs, snowy egrets, great blue herons, and sharp-tailed sparrows. Although salt marsh conditions are harsh – high salinities, flooding, freezing, baking – organisms that can survive these stresses thrive. Salt marshes are among the most productive ecosystems in the world – vying with cornfields and tropical forests. Energy is also woven into the estuarine food-web: salt marshes transform sunlight and carbon dioxide into plants, fish, birds, otters, even people. Our offshore fisheries depend on the energy exported by healthy estuaries and salt marshes. The delicate balance of life in a salt marsh has been challenged repeatedly over the last 350 years. The marshes at Rachel Carson National Wildlife Refuge still bear the remnants of dikes built in the 1800s for salt hay harvesting. Ditches were dug in all East Coast marshes for agriculture and mosquito control. Road crossings have reduced tidal flow to upstream areas resulting in marsh subsidence and conversion to non-native invasive plants. Storm water runoff and creek diversions have also degraded the salt marshes. And from one settled area to another, people have effectively eliminated these ecosystems by filling and draining them. And so we depend ever increasingly on smaller and smaller marshes. But now global climate change and sea level rise threaten even the marsh's ability to provide us with their invaluable benefits. These benefits include converting sunlight and CO2 into plants, transforming that energy base into a multitude of creatures, cycling nutrients, transforming pollutants, trapping sediments, controlling floods, providing protection from storm surges and wave erosion, and renewing the human heart through their beauty. As part of the Land Management Research and Demonstration Program at the Rachel Carson National Wildlife Refuge, we’re investigating ways to restore degraded marshs and increase the resilience of existing marshes so that future generations will be able to share the benefits we have enjoyed. You can help too. Honor the Blue Goose sign by keeping a respectful distance. These areas are sensitive ecosystems. Wildlife here are either raising young or resting during their arduous migrations. Dispose of litter and recyclables properly. Animals are curious and may eat or become entangled in debris. Yard waste also destroys fragile transition habitats, assists invasive plants and ruins everyone’s view. Have a wildlife friendly yard. Plant only native species. Keep areas that border salt marshes in dense woody vegetation. And minimize your use of fertilizers, pesticides and herbicides. Remember, what goes on lawns often washes off into nearby waterways and wetlands. But most importantly, enjoy! Rachel Carson not only fought to keep the environment safe from pollutants, she emphasized the need to share our joy in the living planet; for all of us – young and old alike – to keep alive our sense of wonder.�