Living in a rockpool

Living in a rockpool

Pencil and paperOnline interactive
Overview
Using this Resource
Connecting to the Curriculum
Marking Student Responses
Working with Students
Further Resources
This task is about rockpools and things that live in them.

Question

a) Which diagram shows high tide?

    • rockpool diagram

    • rockpool diagram

b) What do you notice about the shoreline when the tide goes out?

Question 1Change answer

diagram of rockpools   diagram of rockpools
c)  How many times a day does the tide go out?
d) When the tide goes out rock pools are left behind. Why does this happen?

Question

e)  When the tide goes out, which rock pool would form first?

    • A

    • B

    • C

Question 1Change answer

f) What changes would there be to the temperature and water level of the rock pools after exposure to four hours of summer sunshine?
Temperature
Water level

Question

g)  i)  If an animal could only survive in a rock pool for a short period of time, which rock pool would it most likely be found in?

    • A

    • B

    • C

ii) Give a reason for your answer.
Task administration: 
This task can be completed with pencil and paper or online with some auto-marking.
Copyright: 
Copyright: NZCER
Level:
3
Curriculum info: 
Science, Communicating in science, Living World
Keywords: 
ecology, environment, tidal zones, rocky shore, rock pools, diagrams
Description of task: 
Task: students interpret diagrams to consider the effects of tidal changes on rock pools. Assessment focus: relationship of living things with their physical environment.
Curriculum Links: 
Science capabilities
The capabilities focus is brought about by the conversations you have and the questions you ask.
 
Capability: Interpret representations
This resource provides opportunities to discuss using the evidence provided in a diagram that can be used to make inferences.
Science capabilities: 
Interpret representations
Answers/responses: 
 

Y7 (03/2004)

a)

  

very easy
b)  

The sea is further away

or

More of the shore/rocks is exposed/rock pools form

 moderate
c)  

Two times

 difficult
d)  

Water is left behind/trapped in hollows in the rocks

 moderate
e)  

C

 easy
f) i)
ii)

Increase/rise

Decrease/dry up

 moderate
moderate
g) i)
ii)

A

It is covered by water for longer/it is bigger

or

Any response about effect of the conditions in the pool, such as temperature, amount of water, movement of water, salinity (saltiness), food supply, oxygen supply, predators, and how this impacts on fish.

 easy
easy

very difficult

The trial sample was 224 Year 7 students.

Teaching and learning: 
Diagnostic and formative information: 
  • For Question c), 44 students thought there was one tide a day. It may be that these students thought that a day referred to 12 hours rather than 24. Several other students indicated that they thought there was a very large number of tides per day (e.g., 1,000 to 2,000) which may indicate confusion between tides and waves.
  • In Question g) very few students were able to identify why the size and closeness to the sea of Pool A made it more likely that fish could survive there. The students that were able to relate the characteristics of the pool to the impact on the fish said things such as "because fish can't survive in shallow and warm water because they won't be able to breathe".

Further information
Features of rock pools   

  • Pools are left isolated from the sea as the tide goes out.
  • Pools nearer the high tide mark are isolated longer than those further down.
  • Water in rock pools is warmed faster by the sun than water that is mixed by waves.
  • The saltiness of the water may change, either increased by evaporation, or decreased by rainwater.
  • Without wave action, and as the temperature increases, air supplies in the water may run out.
  • Food supplies, e.g., plankton, may run out.

Reference: Department of Education (1969). Biological science. Wellington: Government Printer.

Knowing about tides is an important part of understanding the conditions in rock pools. For example, the height of tides varies between neap tides and spring tides. Other environmental factors such as the wind also affect how much water there is in a rock pool. Some rock pools may only get fresh seawater occasionally, while others may almost always be covered by seawater.

For more information about changes in conditions caused by tides, refer to science notes for teachers in Life between the tides (see Further information).

Next steps: 
Use the students' responses to identify possible gaps in their knowledge about the conditions in rock pools.

If students have a poor understanding of tidal changes students could:

  • look at tide tables to find the pattern of tides;
  • observe tidal changes if rock pools are nearby; or
  • use sequences of photographs of rock pools to discuss changes.

Begin with activities that encourage students to:

  • consider all the different changes that occur; and
  • compare the conditions in the different tidal zones.

Students can then begin considering what adaptations of different animals and plants enable them to live where they do. An alternative approach is to begin with the animals and plants, identify their special features, and then investigate the conditions in their environment they are adapted to survive.

  • Ministry of Education (2002). Building Science Concepts Book 21, Life between the tides. Wellington: Learning Media.
  • Ministry of Education (2002). Building Science Concepts Book 22, Tidal communities. Wellington: Learning Media.
  • Ministry of Education (2001). Building Science Concepts Book 8, The Moon. Wellington: Learning Media.