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Freshwater habitats

Life needs water and so wherever water accumulates on the planet’s surface, life tends to concentrate; whether it’s something as temporary as a puddle or as vast as the ocean. In this book I concentrate the naturalists’ explorations on those readily available pools of freshwater – puddles, ponds, rivers and bogs – focusing on ways to explore the moist worlds and the creatures they contain.

There is no supply of new water on our planet: the water we use has been used and re-used for millions of years. When water is heated it evaporates (like steam from a boiling kettle) and rises until it cools and turns into clouds. These clouds burst when they get too heavy, releasing their vapour as rain falling to the ground. This flows into rivers, lakes and seas, from where the whole cycle starts again.

From puddles to lakes, ditches to rivers, bogs to mires and water butt to fish tank, each contains a whole world of the weird and wonderful, unusual and fascinating. Whether you choose to dive into all the activities I have pulled together from years of being an avid pond dipper or whether you are just looking for a cool way to spend an afternoon, hopefully a page or two will catch your imagination and you will never look at a frog or a water beetle in the same way again!

Different kinds of freshwater attract different kinds of life, which have tuned their lifestyles and body shapes to the challenges that each habitat contains. Life in a pond may look similar to life in a stream – and there may well be overlap for some animals and plants – but look closer and more often than not, the animals and plants differ quite a lot from one another.

The differences are reflected within the pages of this book and broken down into corresponding chapters that deal with each. Many of the activities, however, are not necessarily exclusive to each habitat, so go out with this thought in your mind: ‘Eyes peeled, mind open and net and jam jar ready’ – and enjoy getting wet and muddy.

A boggy bit of land, swamp and marsh may not have much water that is obvious, but the puddles that do exist are often home to some very rare and specialized creatures that can handle the slightly more acidic conditions.

It doesn’t have to be a natural water body to be of interest to wildlife; a simple water butt or a cattle trough will appeal just as much.

This slow-moving mill pond has a rich growth of water weeds and is home to a mixed bunch of animals, some of which are found in both flowing and still water.

A bag of holes!

Naturalists and nets go together like sharks and teeth! They are simply very useful extensions to the human body and allow us to touch places that would otherwise be hard to reach. Nets become the means by which we enter another world. Because of this, there is a responsibility and a code of conduct that should be followed to avoid unnecessary suffering and discomfort to your subjects.

Whatever net you are using, at some point you will have to lift it clear of the water. As soon as the water has drained through the holes, any living things in the net are going to start feeling uncomfortable. So handle and sort the contents as soon as possible. Some creatures, such as adult water insects, are OK for quite some time but other creatures, such as fish and tadpoles, need water to breathe and will also dry out and dehydrate very quickly.

You must make sure EVERY living creature is happy and reasonably content submerged in water – in tubs, buckets, pots and trays – before you start observing any of them.

Nets are invaluable to the water naturalist, but you need to use them in conjunction with a tray or tub. This is so you can sort through what, at first hand, often appears to be nothing but a mass of sludge.

Once you have got a net full of good stuff, it can seem a little daunting peering into the mud, muck and weed and this is where a white tray comes in handy. As soon as you have removed your net from the water, support the bag with one hand and carefully turn it inside out into your white tray already filled with water.

It may still look like a bit of a mess, but spread everything out and let it settle down and from the murk you will start noticing movements as a dragonfly larva stumbles out of the silt or a worm starts wiggling! Now you can start redistributing various creatures into other pots for observation.

Remember to separate predators from prey as in close confines creatures cannot necessarily escape and you end up with a gladiator-style showdown. Not pleasant.

Do not leave specimens in the sun as water temperatures will rise very quickly. As this happens, not only will your creatures – which are totally your responsibility – start to cook, but long before that the water will lose its oxygen and creatures that use gills to breathe will start to suffocate.

Take my advice

* Pond dipping is more than sticking your net in the water and stirring everything up! In fact, doing this is one of the most common mistakes you can make. When approaching any water, keep quiet and move slowly and you can be rewarded with a shy fish basking in the shallows, a frog resting at the surface, a heron fishing or even a nervous water vole.

* Once at the water’s edge, stop and peer into the water to get an idea of what sort of animals you might catch. You may even be able to gently catch an individual there and then without causing too much disturbance.

* Only once you have assessed the habitat is it time to dip your net – gently and carefully. Keep water flowing through the net’s mesh. Move it slowly through the water, but not so slowly that even the slowest beetle can swim out the way it came in! A figure-of-eight pattern is perfect.

Handy stuff: making a net

You can buy a purpose-made net and there are many different kinds to choose from, but it is fairly easy to make your own basic one, which will then be useful in most situations.

The two most important ingredients of a net are the netting itself and the wire surround. For the netting, you want something that is white and of a reasonably fine mesh. White is best because with a dark mesh, too many creatures, even the ones with bad eyesight, stand a chance of seeing you coming!

The holes in your net must be big enough to let the water pass through and drain out easily, but at the same time not so big that all the little creatures get through. It also needs to be robust, otherwise you will forever be replacing the torn bag. I find a tough, coarse cotton fabric is one of the easiest and most practical types of fabric to work with.

Because the wire needs to survive a bit of a bashing, it is best to use a heavy-duty wire that takes a bit of effort to shape. The shape of the net mouth is entirely up to you some people like to have a flat edge, which makes working along the bottom of a pond or river easier. You could otherwise choose to make a circular one.

YOU WILL NEED

> some suitable netting

> needle

> thread

> strong but bendy wire

> wire cutters

> pliers

> bamboo cane

> gaffer tape

1 Decide on the depth of your net. Aim for it being about as deep as it is wide and allow extra fabric to fold over at the top a couple of times. Stitch the turned-down fabric to make a channel. Fold the fabric in half. Stitch along the bottom and up the open side as far as the channel and turn the inside out.

2 Thread the wire through the channel at the top of the bag. For size, you should aim for 20–30cm across. Anything bigger may seem like a better way of catching more, but get a big net full of weed and mud and nobody but Mr Universe would be able to haul the thing in!

3 Cut off the excess wire so that you are left with 7.5cm sticking out at each end. You might want to ask an adult to help you with this next bit – twist together the ends of wire. Pliers can be helpful.

4 Push them into the end of the bamboo cane and . . .

5 . . . use a good length of gaffer tape to keep the cane in place. Now you’re ready to dip!

Handy stuff for exploring with

A naturalist needs nets and they come in different sizes and styles for different jobs. A stout-framed one with coarse netting is perfect as a pond-dipping net; a lighter one with a delicate mesh is handy for catching winged creatures. A butterfly net is useful for catching . . . well, butterflies!

Binoculars These are expensive and one of the few things that you cannot make yourself. But they are well worth the investment and there are many prices to meet different purses. They are especially useful for bird watching, but a close focusing pair are brilliant for watching dragonflies.

Bucket Great for the bigger stuff.

Magnifying lens Another bit of kit that is worth buying. It will turn a mite into a monster.

Plastic pots, trays and plastic aquariums Brilliant for sorting, separating and observing your catches or collecting your specimens in. The clear ones are even more useful in a watery environment as they let you look at the animals from under the surface. Bags are handy lightweight alternatives to pots; they are also useful for keeping plant specimens fresh.

Sieves and tea strainers These are very handy for smaller, close-up work and sorting out creatures once you have caught them. Make them even more useful by strapping the handle to a bamboo cane with gaffer tape (see page 8), rather like the yogurt pot on a stick on page 31.

Stout stick I find this useful as an extra leg, especially when wading. You can use it to test the water’s depth or if you are leaning out with your net, a stick is something that you can lean on for support. With a little tape or string, you can construct a makeshift net handle, too.

Wellie boots Okay, so they aren’t fashionable, but they are a lot cooler than a shoe full of squelchy water or mud.