Eco-Schools Lesson Plan
Lesson title: MARINE FOOD CHAINS
Key Stage: 1 & 2
Resources & Preparation:
1. Bookmark websites for pictures of marine mammals and marine life in
general. We suggest:
 Sea Watch Foundation Species Identification Guides (whales,
dolphins & porpoises):
http://www.seawatchfoundation.org.uk/speciesid.php
 For pictures of phytoplankton and zooplankton, you can use Google
Images or MarineBio: http://marinebio.org/oceans/forests/
In addition, Appendix 1 contains a selection of pictures of marine life that
students can copy or cut out.
2. Materials to make a food chain: string/thread, sticks/straws, paper/card,
scissors, colouring pens, sticking tape.
Subjects: Science / Art & Design / ICT
Extension Activity: Science / Art & Design / English
Lesson Objectives:
Students will …
 learn generally about the interdependence of sunlight, plants and animals.
 learn specifically about the connections between marine plants and animals
by drawing or making a food chain using a variety of materials.
 educate others about food chains by exhibiting their work.
Risso’s dolphin. SWF/Peter Evans
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Introduction:
 A food chain is “a feeding hierarchy in which organisms in an ecosystem are
grouped into nutritional (trophic) levels [that] are shown in a succession to
represent the flow of food energy and the feeding relationships between
them.”¹ Put simply, it is about what provides energy in the form of food for
what.

Within marine ecosystems marine mammals are often the predators at the top
of the food chain. The health of marine mammals in terms of the size of
populations and their distribution can reflect changes occurring further down
the food chain, for example, through over-fishing or pollution.

A food web is “many food chains linked together to show a more accurate
model of all possible feeding relationships of organisms in an ecosystem.”² By
mapping the connections between organisms, you can get a broader
understanding of a marine ecosystem and see how the health of one species,
for example, through over-fishing or hunting, can have many effects.
Activities (lesson plan):
1. Think about familiar food chains. Introduce the idea of food chains with
familiar examples. For instance, you can ask students if they drink milk. Then
ask where the milk comes from (a cow/sheep/goat) and what that animal eats
to get energy to produce milk. Cows eat plants, usually grasses and legumes
(clover, alfalfa, etc). Finally, ask where the grass gets its energy from – the
sun in the form of sunlight. From these answers, you can build up a diagram
on the board showing the energy flowing up from the grass to the human
consumer and introduce the term ‘food chain’. Alternatively, use sunshine /
tree (apple) / human as a food chain.
2. Marine food chains. Since marine food chains will include plants and
animals that are unfamiliar to your students (see the glossary for simple
definitions), rather than eliciting the food chain you could write the names
randomly on the board, or put them onto cards, and, after explaining what the
unfamiliar organisms are, ask the students to arrange them in a food chain
with sunlight as the original energy source, for example:
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sunlight / kelp / periwinkles / edible crab / bottlenose dolphin;
sunlight / phytoplankton / zooplankton /sand eel / mackerel / gannet;
sunlight / phytoplankton / zooplankton / fin whale;
sunlight / phytoplankton / krill / squid / sperm whale;
sunlight / phytoplankton / zooplankton / fish / seal / killer whale;
sunlight / phytoplankton / mussels / starfish / edible crab / bottlenose
dolphin;
sunlight / phytoplankton / zooplankton / jellyfish / leatherback turtle;
sunlight / phytoplankton / zooplankton / sand eels / herring / grey seal;
sunlight / algae / limpet / dog whelk / oystercatcher.
3. Make a food chain. Discuss with the students the best way to represent a
food chain. Representations could be two-dimensional drawings, created
using ICT or three-dimensional mobiles. For a mobile, students draw, colour
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and cut out pictures of the organisms in their food chain. Then, they tape the
organisms to string or embroidery thread with the sun at the top or bottom to
represent the flow of energy.
4. Display the marine food chains. The students can display the completed
marine food chains in a place where other students or people can see and
learn from them, putting emphasis on how to portray the information visually
so that it is easy to understand. Students may want to present or talk about
their work with others.
5. Discuss effects of changes in the food chain. Ask the students questions
that will encourage them to think about the interdependence of food chains:
 Sunshine / phytoplankton / zooplankton / fish / seal / killer whale – in this
food chain what would happen if most of the fish were fished and eaten by
people? What would happen if the number of seals increased?
 Ask similar questions about the food chains that the students have made.
Rhizostoma. SWF/Peter Evans
Extension activities:

Introduce food webs. On the board begin another food chain: sunshine /
phytoplankton / zooplankton / fish / seal. Then stop and ask the students if
fish are only eaten by seals. Ask what other animals (mammals, birds) eat
fish. Use the answers to build up a more complex picture of the energy
interactions within the marine habitat. Include people into the web where
relevant. [Science]

Play the food web game. This game provides a clear and tactile
representation of how a food web is built and how it is affected by change. It
requires a large space, preferably outside. Give each student a card with a
different marine plant or animal on it. The student with the ‘sun’ card stands in
the middle. Give the ‘sun’ student a ball of wool or string. Read out one of the
example food chains, for example, sun / kelp / periwinkle / edible crab /
bottlenose dolphin. Each student who is called out wraps the wool around
herself or himself and passes it on. When the ‘food chain’ is finished, cut the
wool. Return the wool to the sun again and begin with a different food chain.
Repeat the process until all the chains have been completed. Once the food
web is formed, ask the students questions about the effects of a decline or
rise in one of the species. The students can pull the wool to see which other
species would be affected. [Science]

Make a marine mammal food web. Instead of, or in addition to, making a
food chain, the students can make a food web in groups or as a class. The
food web can take many forms depending on the time and materials available
and the interests of the students: an ICT representation; a drawing; a large
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collage; a three-dimensional mobile using sticks or straws horizontally to
represent the different energy levels and tying thread between cut-outs to
show connections. To be accurate, it would work best if the students chose a
particular area of the UK (perhaps the closest marine area to them) and
include the marine plants, birds and marine mammals living and interacting
there. The students should add humans to the food webs where applicable.
When completed, discuss with the students whether the web they have made
makes it easy or not to understand the relations between marine life-forms.
[Science / Art & Design]

Make a species fact sheet. Students can make a simple fact sheet about a
particular species from the food chain that would include: species name, a
colour drawing, where it lives, what it eats and what eats it. The students can
then use the fact sheets to talk about the similarities and differences between
the marine organisms. [Science / English]
Leatherback turtle – Irish Sea. SWF/Peter Evans
Curriculum Links:
Science
Sc1
Pupils should be taught to:
2(h) make simple comparisons and identify simple patterns or associations.
Sc2
Pupils should be taught:
1(b) that animals move, feed, grow, use their senses and reproduce;
2(a) to recognise and compare the main external parts of the bodies of humans and
other animals;
(b) that humans and other animals need food and water to stay alive;
3(a) to recognise that plants need light and water to grow;
5(c) to care for the environment.
Breadth of study
Pupils should be taught to:
2(c) use simple scientific language to communicate ideas and to name and describe
living things.
Art & Design
Pupils should be taught to:
1(b) ask and answer questions about the starting points for their work and develop
their ideas;
2(c) represent observations, ideas and feelings, and design and make images and
artefacts;
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3(a) review what they and others have done and say what they think and feel about
it.
Breadth of Study
Pupils should be taught the knowledge, skills and understanding through:
5(a) exploring a range of starting points for practical work;
(b) working on their own, and in collaboration with others, on projects in two and
three dimensions and on different scales;
(c) using a range of materials and processes.
ICT [if used]
Pupils should be taught:
1(a) [how to] gather information from a variety of sources;
2(a) to use text, tables, images and sound to develop their ideas;
3(a) how to share their ideas by presenting information in a variety of forms;
(b) to present their completed work effectively.
Sources:
¹ http://www.biology-online.org/dictionary
² http://www.biology-online.org/dictionary
³ http://www.bbc.co.uk/nature/blueplanet/factfiles/molluscs/dog_whelk_bg.shtml
Glossary:
algae (noun) – a marine plant.
dog whelk (noun) – a sea snail found on rocks on the sea-shore that feeds on other
animals, usually limpets, mussels and barnacles.
kelp (noun) – a sort of seaweed; seaweed gets its energy from sunlight.
krill (noun) – shrimp-like zooplankton.
limpet (noun) – a sea snail found on rocks on the sea-shore.
periwinkle (noun) – a small sea snail found on rocks on the sea-shore.
phytoplankton (noun) – tiny algae (marine plants) that live near the sea surface to
get energy from sunlight (for photosynthesis).
sand eel (noun) – a long, thin fish.
zooplankton (noun) – small organisms (animals), for example, young crustaceans
and fish, that feed on phytoplankton. Zooplankton are eaten by small fish.
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Appendix 1
Pictures of marine organisms to copy
seaweed
mussel
periwinkle
starfish
oystercatcher
gannet
porpoise
limpet
jellyfish
crab
fish
seal
dolphin
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