Salt Marsh Ecology HOBCAW BARONY

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1 Lesson Description This program focuses primarily on the plants and animals of the salt marsh, but includes animals of the forest as well. Students are introduced to both environments through exhibits in the Hobcaw Barony Discovery Center. As the class heads out to the salt marsh, they ll travel through the longleaf pine forest viewing and discussing the different stages of the longleaf pine tree as well as keeping a look out for animals. Once at the marsh, students will search different areas for animals and plants and observe how they depend on one another. The salt marsh will be hands on, holding fiddler crabs, feeling and tasting pickle grass and cordgrass, holding periwinkle and coffee bean snails and searching for amphipods. SC State Standards covered Standards Standard 1-2: The student will demonstrate an understanding of the special characteristics and needs of plants that allow them to survive in their own distinct environments. (Life Science) Standard 2-2: The student will demonstrate an understanding of the characteristics of organisms. (Life Science) Indicators Recall the basic needs of plants (including air, water, nutrients, space, and light) for energy and growth Illustrate the major structures of plants (including stems, roots, leaves, flowers, fruits, and seeds) Classify plants according to their characteristics (including what specific type of environment they live in, whether they have edible parts, and what particular kinds of physical traits they have) Recall the basic needs of animals (including air, water, food, and shelter) for energy, growth, and protection Classify animals (including mammals, birds, amphibians, reptiles, fish, and insects) according to their physical characteristics Explain how distinct environments throughout the world support the life of different types of animals Summarize the interdependence between animals and plants as sources of food and shelter Illustrate the various life cycles of animals (including birth and the stages of development).

2 Focus Questions 1. What are the basic needs of animals? 2. What is an estuary? 3. What is one characteristic of a fiddler crab? 4. What is an animal adaptation? 5. What is detritus? Teachers need to provide: Pencils (one per student) Clipboards (one per student) Salt Marsh animal sheet & Questions o (one copy per student per page) o Look for the Instructor will provide: Plant/animal cards Lesson Plan Part One: Salt Marsh Ecosystem Overview To begin this lesson, students will sit around the front of the 1200-gallon salt water aquarium located in the Hobcaw Barony Discovery Center. The instructor will use plant and animal cards to show species that live in the marsh ecosystem and discuss how each species is classified based on their characteristics. Part Two: Fashion a Fish In this section of the study, students will learn to categorize animals based on their coloration and body shape. Part Three: Field Observations Field observations will take place out on the salt marsh trail where students will be immersed in the marsh ecosystem. Using clipboards, pencils and the animal worksheets, the instructor will lead the students through the four zones of the salt marsh allowing them to see variations of habitats/animals in this ecosystem.

3 Teacher Preparation: An estuary is the thin zone along a coastline where freshwater systems and rivers meet, mix with a salty ocean, and become brackish. An estuary begins where fresh river water flows into coastal bays and inlets. These areas of transition between the land and the sea are driven by tides, like the sea, but sheltered from the full force of ocean wind and waves, like a river. When fresh water meets salty seawater, both liquids combine turning into a brackish mixture. Estuaries are unique places that are valuable to the environment and to society. Each having its own specific characteristics, they all play vital roles in the environment and in our lives. Estuaries change constantly, and this change is necessary for an estuary s health. Estuarine organisms have adapted to tolerate the changing conditions of estuaries. Tides, depth and location, weather patterns, seasonal cycles, and climate change all lend to the ever changing characteristics of an estuary. Tides are necessary for healthy estuaries as they flush the systems and provide nutrients to keep the food webs functional. However, tides create constantly changing conditions of exposure to air and inundation to water. The depth and location of an estuary affects and changes conditions such as temperature and number of organisms present. The Earth s climate is warming at a faster rate than normal. This warming is causing sea level to rise, which may ultimately result in flooded and lost estuaries. A common estuarine habitat found here in South Carolina is coastal marshes. Coastal marshes along the oceans are called salt marshes, or tidal marshes. Salt marshes prefer cool, temperate climates (winter temperatures near or below 10 o C). They occur in areas that are directly affected by tidal waters. Many different types of plants such as marsh grasses, rushes and sedges grow in salt marshes. These different types of plants require different water levels, oxygen content and salinity which determine where they grow in the lower, middle or upper marsh. Salt marsh plants are highly tolerant of the salty waters. They absorb the estuary waters through their roots, and special plant cells concentrate the salt ions, freeing up freshwater to be used by the plant. Salt marshes can filter small amounts of pollutants and runoff while the marsh grass filters and traps silt. However, too much nutrient or sediment input will create an unbalanced situation causing the health of the marsh to decline. Salt marshes provide important protection and nursery areas for fish, shellfish and crustaceans. Small fish and other animals live in the shallow waters and dense grasses and hide here from predators. Salt marshes also trap decaying organic matter (detritus) that is used as food by some estuarine animals. Salt marshes provide food, fresh water and shelter for migrating birds on their long journey between nesting and wintering habitats. Salt marsh plants have strong root systems that help them withstand surges of water that come from storms. Many winding creeks and channels snake through salt marshes. They carry detritus and deposit sediment, replacing what storms, floods and tides flush out. Salt marshes develop in low energy waters, meaning that there is usually only a small amount of wave action in the area. Decaying plants, fish and animals are broken down by bacteria and fungi helping produce the ripe, rotten egg smell common in salt marsh mudflats. *Excerpted from estuaries.noaa.gov

4 SALT MARSH ECOLOGY VOCABULARY LIST Adaptation (adapt): a genetically-based body feature or behavior that allows an organism to be better suited to its environment. Anaerobic: without air, no oxygen. Benthic: relating to the ocean bottom. Brackish: slightly salty water with salinity between 0.5 ppt and 32 ppt. (ppt = parts per thousand) Conservation: careful preservation and protection of ecological processes and biodiversity of the environment Detritus: newly dead or decaying organic matter coated with bacteria. Estuary: a semi-enclosed body of water which has a free connection to the open sea and within which seawater is measurably diluted by fresh water derived from land drainage. Some unique Great Lakes coastal wetlands are referred to as freshwater estuaries. They occur where rivers and Great Lakes water mix in shallow wetlands located near the mouth of a river. High marsh: the area of the marsh flooded infrequently by the high tides associated with new and full moon. Intertidal: estuary habitat flooded by high tide waters only. Invasive species: non-native species of plants or animals that out-compete native species in a specific habitat. Low marsh: the area of marsh flooded twice daily by tides and dominated by Spartina alterniflora. Pelagic: of or in the open ocean or open water; in the water column. Salinity: the concentration of salts dissolved in salt water. Tides: periodic rise and fall of ocean waters due to gravitational pull of sun and moon, and rotation of earth. Wrack line: a string of debris stranded by last high tide; cast ashore seaweeds, isolated sources of food and shade support an important community of isopods and amphipods as well as providing food for birds.

5 Background: Salt Marsh Values Salt marshes in the United States occur along the Atlantic Coast from New Jersey to Northern Florida and along the Gulf of Mexico. These coastal estuaries are considered some of the most fertile ecosystems in the world. South Carolina alone contains over 400,000 acres of protected salt marsh. These marshes help to protect the mainland during storms, filter pollutants entering wetlands and oceans, and act as a nursery for numerous species of fish, shrimp, crabs. Salt marshes are also an area full of commercial and recreational opportunities. Cultural While salt marshes were long considered of no value, strictly in terms of agricultural dollars, they have been part of the lifeblood of many living along the coast for centuries. Native Americans harvested oysters and clams, throwing them into trash piles that we now call shell middens. Colonists fished the same areas and rice planters spent summers at the salt marsh because of the lack of mosquitoes that carried malaria. Due to unique networks of tide-controlled fresh water rivers and rich, loamy, marshy areas, the planting of rice here was ideal. Winyah Bay, the third largest estuary on the east coast, was also the location of the historic commercial fishing of sturgeon for caviar, and our estuaries still offer a cultural connection to our coastal communities of today with a variety of recreational activities. Ecological Salt marshes are extremely fertile; there are over 900 of species of fish and invertebrates living in tidal creeks, estuaries and nearshore areas in South Carolina. Our coast s twice daily tides (2 high and 2 low) are necessary for healthy estuaries as they flush the systems and provide nutrients to keep the food webs functional. The cycling of two nutrients, nitrogen and phosphorus, is especially important in estuaries. In the water cycle, estuaries serve as places where evaporation of water occurs, and also serve to recharge ground water. Economic Healthy estuaries and salt marshes are critical to ocean dependent industries such as tourism and commercial fisheries. In a 2009 economic report for Horry and Georgetown Counties in South Carolina, tourism accounted for over 98% of almost 25,000 ocean dependent jobs. According to the South Carolina Department of Natural Resources, commercially important species of shrimp, oysters, clams and blue crabs were valued at $14.81 million in Recreational fisheries also provide millions of dollars to the state s economy each year. Response to Climate Change Research conducted at Hobcaw Barony has shown that there are effects of climate change in our area. According to current research by Dr. Dennis Allen with the Belle W. Baruch Institute for Marine and Coastal Sciences, since the 1980 s the winter water temperature has increased by 2 degrees Celsius. Long term monitoring of North Inlet estuary indicates that sea level is rising in our area at an average rate of 3 millimeters per year and the projection is that this rise will escalate. For North Inlet, this means that areas of the salt marsh could drown and convert to less productive open waters.