Wetland Ecosystems, Non-living and living components and Brine Shrimp
Grade level(s):Grade 6, Grade 7
Understand that a wetland ecosystem has a living and non-living components ant that organisms depend on these other organisms and the environment to survive.
biotic, abiotic, wetland, ecosystem, brine shrimp, algae, saline, exoskeleton, hemoglobin,
What you need:
Photos of wetland birds, Chart paper for wetland ecosystem discussion, Chart paper for discussing the brine shrimp (living and non-living components), Brine shrimp sample and viewers with magnification, Brine shrimp worksheet, Map of Bay Area Wetlands
Students work in whole class and small group settings to discuss, observe and learn about a wetland ecosystem (salt ponds) and some of the organisms that live there. Abiotic and biotic factors of species survival are discuss. Live brine shrimp are used in observation.
Understand that a wetland ecosystem has living and non-living components and that organisms depend on other organisms and the environment to survive.
For a nice photo of male and female brine shrimp (Artemia salinia) please go to this link: http://www.naturamediterraneo.com/forum/topic.asp?TOPIC_ID=11081
Purchase live brine shrimp from a local aquarium store.
Lesson Implementation / Outline
Anticipatory Set/Introduction: Display poster and photos of wetland birds. Ask students to look at the birds and to decide where they might live (which ecosystem) based on its characteristics. The students will likely guess the birds are from a wetland ecosystem based on their feet and beaks.
Begin by explaining to the students that today they will learn about the wetland ecosystem, which is one that we have nearby with in the bay area, and that we will discuss how different organisms need living "things" and non-living things to survive. Ask students to generate a list of places they would likely find water within 50 miles of the school. Record all the ideas on the whiteboard (list may include tap, bathtub, river, marsh, lake etc.).
Once the list has been generated ask the students if any of these might be part of a wetland ecosystem.
Ask the students what does the term wetland ecosystem mean? Draw attention to the two words "wetland" and "ecosystem". Tell the students that a wetland is a term that refers to the partial flooding of an area of land for a short or long duration in which a close relationship between the water and land organisms exists. In particular a large diversity of plants and animals live in the transition zone between land and water. Tell them that an ecosystem is a place where things live together. It refers to the relationship which exists between the living and non-living components of an environment. Ask students to name some living things (biotic factors) in an ecosystem (birds, plants, fish, and mammals) and to name some non-living things (abiotic factors) an ecosystem (sunlight, water, soil, rocks). Explain that all of these things are necessary for organisms in the ecosystem for food, shelter and survival. Guide the students in completing the wetland ecosystem chart. Ask students for the names or locations of three wetland ecosystems, where they might find things living on, in, and around the water (this list might include pond, marsh or river).
For each of the three locations ask the students what organisms live in the water? (fish, shrimp, plankton). What organisms live on the water? (ducks, geese, duckweed). What organisms live beside the water? (snakes, mice, plants) Introduce the salt pond as part of the local San Francisco Bay wetland ecosystem. Show students the map of the bay and the locations of the salt ponds. Introduce the brine shrimp, write the scientific name Artemia franciscana on the board. Tell the students that they are only found in very salty (or saline) water (places where sea water collects in pools and evaporates). Tell the students that many S.F. Bay marshes were destroyed to build salt ponds (to produce table salt for people to eat), but that the salt ponds provided new habitat for brine shrimp. Tell the students that the brine shrimp are crustaceans, ask what other animals are crustaceans? (crabs and lobsters). Tell them they have a hard shell on the outside, ask the students what we call that (an exoskeleton; exo=outside), and that like a crab or some insects they must molt to grow larger. Tell them that they have a mouth and compound eyes (like an insect). Tell the students that they have 22 legs and that they "breathe"? (obtain oxygen) through their legs (with gills, like fish).
"Ask students what do you think they eat? (Algae- tiny floating plants in the salt pond).
"Which animals eat them?" Brine shrimp are an important source of food for birds such as the avocet, black neck stilt, and willets and as well as some fish and insects. Show students the worksheet to fill out. Tell the students that you will pass out the brine shrimp and a worksheet. Tell them that they need to observe, draw and take notes on the brine shrimp for 3-4 minutes and then we will discuss the worksheet. Distribute the containers with the brine shrimp (one container per 4-5 students) and the worksheets to the students. After the students have drawn and taken notes, ask: what do you notice about how they move?
They will notice as they look at them that the shrimp continuously move there legs. Ask the students why? They must keep water moving over there gills to supply themselves with oxygen. Ask which two abiotic factors here do they depend on (water and oxygen). Ask: what do notice about the color?
Tell the students that because they live in salty water (which holds less oxygen than fresh water) that they must produce hemoglobin (which is the same as in our blood) to store oxygen and it makes them look red/orange, like hemoglobin makes our blood red. Ask if any students see two little black dots on the backs of the brine shrimp. Have the students guess what they are. Explain to the students that they are egg sacks and therefor those are females. Tell the students that sometimes the baby brine shrimp hatch inside the egg sack and are released live, but more often the female release the eggs before they hatch. A baby brine shrimp has no tail or legs at first, but grow these later. Most brine shrimp live for 2-3 months. Tell them that when salt ponds dry up during the summer, that the eggs dry out and remain in the pond, and when the pond fills with water again during the winter the eggs have a ready supply of salt water and can hatch and live again. Close by asking students what living things and non-living things do the brine shrimp depend on.
Ask students: what kinds of living things and non-living things do you depend on?
Check in with students on their assignment and look for understanding or confusion. Check by asking students clarifying questions. What do you notice about the brine shrimp's movements? Why do you think it moves that way? What do we call the type of skeleton that some animals have on the outside of their body? What makes their bodies orange in color?
Strategies/Accommodations for Special Need Students:
- Teacher will assign a buddy to students who may have trouble with the vocabulary on the worksheet.
- Students who will have difficulty copying down information can be provided with a worksheet with the information already written in. They will have access to the same information that other students will copy down.
- Check with students for understanding and how they are progressing with worksheet. Encourage students to observe and just make a casual sketch of something they see.
Close by asking students what they learned today and tell them that today they learned about wetland ecosystems and some of the nonliving and living things that are necessary for one organism (the brine shrimp) to survive.
Extensions and Reflections
Lessons on other ecosystems. Research into Biomes and the animals and plants that occur in those areas.
Students love live animals (of any size) and this is a good way to introduce students to an ecosystem and species that they may be unfamiliar with. Live brine shrimp will last for about 5 days, they need aeration to do best.
This lesson can easily be altered to make it more inquiry based. Have students FIRST observe brine shrimp, write down questions and things that they are wondering about.
Based on their observations, have students discsuss what THEY think about a.) where the shrimp might live b.) what food they eat c.) how they breath etc. and have them explain their choices.
Weblinks and References
|Lifecycle of the brine shrimp.doc||64 KB|
|Student worksheet.pdf||541.01 KB|
|Brine Shrimp Worksheet answers.pdf||224.38 KB|