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Project title or topic of activity

Feeding Habits of Marine Animals

Author(s): April Huff, Rob Wiruth, Sean Keel, Caro Castro

Date: April 27, 2001


Summary of Activity

This activity is a 20 to 25 minute station that is designed to educate students about animals they might not have recognized as conventional animals, as opposed to plants or algae. Animals eat other organ isms, while plants and algae make their own food using energy from the sun. Animals are consumers (eating other organisms), while plants and algae are primary producers (producing their own food and making food for animals).

For the first five minutes, the students distinguish between various plants and animals using pictures of the different organisms. Next, the students learn about marine animals with various feeding habits, and then observe organisms in a large salt-water tank in CBS rm 511 to look at live specimens of corals and tube worms. Then the students explore the feeding habits of the marine animals. The feeding types include suspension, deposit, and filter feeding, plus predation and scavenging. Finally, the students engage in a hands-on activity demonstrating the various feeding habits of the marine animals. These animals include tubeworms, barnacles, brittle stars, snails, and hermit crabs. The students choose one animal they particularly find fascinating and instruct the other students about what they have learned about the animal.


Grade levels

Grades 3-7 with a group size of 4-8

Background information


The scientific principles that the activity are based upon:

  • This activity focuses on educating students about marine animals that do not look like conventional animals.
  • Define plants, algae, and animals and know the differences between them.
  • This activity will appeal to student's curiosity, through hands-on participation and interactive instruction. The students will work individually and in small group exploring the feeding habits of presented marine animals. After learning about a particular marine animal, students will locate the organism in the salt water tank and will summarize the animal’s feeding habits to their fellow students


    Background Information for plants, animals, and algae

    Animals are heterotrophic organisms, while plants and algae are homotrophic. The main difference between plants and algae are that plants contain two types of chlorophyll and receive oxygen from the air, whereas most algae only have one type of chlorophyll and receives oxygen from water.


    III. Activity Two

    1. Divide students into four separate groups
    2. Assign each group a feeding habit (filter, suspension, deposit, predator)
    3. Explain the rules of the activity
      1. The pieces of paper represent food that students are only allowed to gather by their assigned feeding method
      2. Filter feeders use a hand held fan to blow pieces of paper toward them.
      3. Predators will be able to walk around to grab large pieces of paper.
      4. Suspension feeders use a sticky hand to snatch smaller paper
      5. Deposit feeder must creep slowly and can only pick up paper on the floor.
    4. Let the activity go on for about a minute and then regroup students for a discussion
    5. Ask the students about what their limitations were and how this would affect where an organism can live in a marine environment
    6. Common Problems the instructor might encounter
      1. Student might be distracted by all the activity
      2. Horseplay could be problem during this activity

    Background Information on Feeding Habits

    • Deposit feeders pass sand, mud, water or sediment into their mouths using mucous-covered tentacles or arms, or by a mucous net. Organic material is then removed from the deposit and digested. The rest of the deposit simply passes through the gut of the organism. Deposit feeders are not predators. Examples of deposit feeders include sea cucumbers and feather dusters.
    • Suspension feeders catch food or organic material from the water using tentacles or spiny arms. They do not create a current like filter feeders yet just let the food come to them and then attach onto it with their tentacles or arms. Some examples of suspension feeders are the anemone, coral, hydroids and brittle stars.
    • Filter feeders; capture food that is suspended in the water by creating a current within them for the water to flow through. Prey is captured as the current passes through the animal; the prey is filtered from the water as the water passes through the animal
    • Predators actively seek out their prey items. In the ocean, some predators can be adapted to blend in with the surrounding area and wait for a prey item to pass by or they can be adapted to move quickly to chase down prey. Examples of predators are the grouper, triggerfish, and panamic sea star.

    IV. Activity Three

    1. Show children the live animals and remnants of animals.
    2. Let the students carefully handle the animals
    3. Ask the students what the animals eat and how they eat.
    4. Go into discussion about the feeding habits of the different animals.
    5. Common Problems

1. Students might handle the animals roughly and need to be reminded to be gentle.

V. Activity Four

  1. Ask students to point out their favorite animal in the area and how that animal eats

Credit for the activity

The group members, basing some of it on the Rocky Intertidal station, developed the activities for this station. 

Estimated time to do the activity/activities

This station should take about 25 minutes.

Goals of Activity/Activities:


1. This activity will allow the students to distinguish between plants and animals in the marine world.

2. Students will gain knowledge of different methods of feeding in marine organisms.

3. Students will get a hands on experience investigating these unusual animals.

4. Students will be able to work together and play a game that will demonstrate the feeding strategies discussed in the station.


Materials Needed

Materials for a group of 5 students:

Activity One

  • Laminated cards with pictures of different organisms. These include pictures of both plants, algae and animals. The plants, algae, and animals included on the cards are a lion, a violet, clam, barnacle, coral, clown fish, oak tree, green algae, sea anemone, and a sea cucumber.

Activity Two

  • One or two sticky hands. Sticky hands are toys for children that are generally bought from vending machines.
  • Small hand-held fan.
  • Different sized pieces of paper to represent food, enough for several handfuls.

Activity Three

  • Several pieces of animal remnants, i.e. shells, tube worm cases, sea urchin tests, etc.
  • Large salt-water tank filled with live organisms, i.e. fish, sea cucumbers, etc.
  • A few smaller bowls filled with live snails, crabs, sea urchin, and brittle stars.

Activity Four

Same materials as those used in Activity Three.

Preparation & teacher "heads up"

Preparation includes setting out the cards with the pictures of organisms on it for the first activity. For the second activity, the sticky hands, hand fan and different types of food must be pulled out. The live animals need to be placed into the glass bowls filled with salt water and placed a table that students can gather around. These animals include snails, brittle stars, the sea urchin, and hermit crabs.

Step-by-Step Procedure

I. Introductions

II. Activity One

A. Gather students around the a table with pictures of animals, algae and plants

  1. Ask students what characteristics distinguish animals from plants and how plants and animals are different from algae.
  2. Have students group the pictures into animals and plants
  3. Correct any mistakes and explain why
  4. 1.Common Mistakes Made or Reasoning Used

    1. Cannot see a mouth, eyes, nose, etc.
    2. Since there is not mouth, they cannot eat
    3. Be able to anticipate and respond to how coral, sea anemone, and sponges are animal

Images, work sheets, additional web pages

The only images we used are the cards with pictures on them.

Items for discussion or conclusion

The fourth activity will be the conclusion activity for this station. Students will be able to choose an organism and discuss how it feeds and what it eats.


If the students are able to discuss the feeding habits of different organisms in the fourth activity, then the goals of this station have been met.


Beyond the Activity
Further activities which relate to and extend the complexity of the experiment.

They can use their new knowledge of feeding habits of marine animals and apply it to feeding habits of land animals. Examples include spiders as suspension feeders, lions are predators, and vultures are scavengers.

Web Resources
A web address with information on the topic of the activity.

Web Address

Additional References


Moyle, Peter B. Fish: An Enthusiast’s Guide. University of California Press, Berkeley: 1993.

Buchsbaum, Ralph, et al. Animals Without Backbones. The University of Chicago Press, Chicago: 1987.


Spanish keywords

Algae = las algas

Plant = las plantas

Animal = los animals

Suspension feeder = alimentador de suspension

Filter feeder = filtre alimentador

Deposit feeder = deposite alimentador

Predator = el animal de rapina

Scavenger = el animal que se alimenta de carrona

Fish = pez

Tube worm = el gusano del tubo

Barnacle = el percebe

Sea urchin = urchin del mar

Brittle star = la estrella quebradiza

Sea cucumber = el pepino del mar

Snail = el caracol

Hermit crab = el cangrejo de hermit

Coral = el coral

Sea anemone = la anemona del mar

Sponge = la esponja

Clam = la almeja

Plankton = el plancton

Oak tree = el roble

Violet = la violeta

Lion = el leon

Shell = el esqueleto

Test = la prueba

Case = el caso

Common Phrases

What is this?

?Que es esto?

What is this called?

?Como se llama esto?

Look at this.

Mira esto.

How does this eat?

?Como come esto?

What does this eat?

?Que come esto?