Animal variety

A typical pond is home to an amazing variety of snails, worms, freshwater shrimps, water spiders, water bugs and water beetles, all of which spend their complete life cycle in the pond. Also there are the young stages of insects, e.g. mayfly nymphs, dragonfly and damselfly nymphs, caddis fly larvae, bloodworms and midge larvae, which eventually emerge from the pond as flying adults.

Aims: To show children how many different types of minibeasts there are and to point out some of their peculiarities. Also to demonstrate that different types of animal live in different parts of the pond.

Activities

1. What's this?

When pond-dipping, children can be encouraged to look in the minibeast guides provided and identify for themselves what they've found. These can be noted down by writing names or drawing. Try grouping animals according to observable similarities and compare with minibeasts found on land, e.g. pond snails with land snails.

2. Which animals live where?

In groups, children can search different zones of the pond:

• on the surface
• in open water
• in underwater plants
• in the mud at the bottom

Record your findings for further work in the classroom. Make models and pictures of the pond to show its zonation.

3. Where are the most flatworms in a pond?

Flatworms will cling to a piece of meat. Try lowering lumps of liver tied onto string into different parts of the pond. These can then be left for about two hours then raised to see how many flatworms there are in different parts of the pond.

4. Attracting pond creatures

Extending activity 3, pond creatures can be obtained by providing other suitable baits or microhabitats. For example, suspend pieces of meat, bunches of leaves or other materials and check to see what creatures attach themselves. Fill a net bag (e.g. the type used for oranges) with pebbles and leave it in the pond for a few weeks. Empty the bag and see what has colonised. Try to think of other microhabitats which might attract a different range of species.

5. What am I?

See animal identification activities.

6. Freshwater pollution

The range of invertebrates caught in a pond, river or stream gives a useful indication of the occurrence or otherwise of eutrophication (overfeeding of the water with nutrients). Bloodworms (chironomid larvae), sludge worms (Tubifex) and rat-tailed maggots (drone-fly larvae) have adaptations which allow them to breathe under the deoxygenated conditions caused by such pollution. If there are few species other than these, the water is likely to be polluted in this way. If very heavily polluted, there will of course be no life at all. Water lice, leeches, flatworms and pond snails may be found in addition if the pond is only moderately polluted. Freshwater shrimps are among the indicators of clean water, which will also contain a good range of other species including dragonfly, damselfly and mayfly larvae and freshwater limpets. You will find an activity sheet on this later in the pack.

Pond Pack Introduction Why study ponds? Pond-dipping Safety for teachers Safety for kids Animal variety Moving and breathing Cycles of life Webs of life Plant life Maths English Geography History Art and design Make a pond Plant identification Animal identification Activity sheets Bug dial Where to go Acknowledgements EDUCATION NATURE SEARCH . . . . . . . . .