Why Britain's amphibians need a hand

The common frog and the common toad are among the most familiar wild creatures in Britain, and both have had a difficult few decades. Thousands of field and farm ponds disappeared through drainage and changes in farming during the twentieth century, and many of those that remain are isolated, shaded, polluted or stocked with fish. In much of lowland Britain, garden ponds now make up a substantial share of the still fresh water available to wildlife. Your small patch of water matters far more than it looks. Build it with the right features, in the right spot, and frogs and toads will usually find it within a season or two.

Getting the pond itself right

A wildlife pond does not need to be large. Something around two metres by three is plenty, provided it is designed with amphibians in mind.

• Include at least one shallow shelf roughly 10–20cm deep. These warm up quickly in spring, which is exactly where frogs and toads choose to lay.
• Dig a deeper section of 60cm or more in the middle. This keeps the pond from freezing solid in a hard winter and stays cooler in summer.
• Position it in part sun and part shade. Several hours of sun a day encourages spawning and plant growth without turning the water into a green soup.
• Keep fish out. Even a few goldfish or orfe will clear a pond of tadpoles in weeks. A wildlife pond needs no pump, filter or chemical treatment.
• Plant with native species such as hornwort, brooklime, water mint, water forget-me-not and marsh marigold. Never introduce invasive plants like New Zealand pygmyweed, floating pennywort or water fern – they can escape into the wider countryside.

Rainwater is ideal for filling a new pond. If you must use tap water, let it stand for a few days first so the chlorine disperses.

Small design details that save lives

Most amphibians that die in gardens drown not in the pond but because they cannot get out of it. Steep, smooth butyl or concrete sides are a death trap for frogs, toads, hedgehogs and beetles alike.

• Build one gently sloping beach of turf, gravel or pebbles that runs straight into the water.
• Add half-submerged logs or a sturdy ramp of stone or wood at another point, so anything that falls in has a route back to dry land.
• Leave a few stones and broken slates on the pond floor as cover for newts and resting tadpoles.
• Keep the water level fairly stable in spring. A sudden drop can strand spawn on a dry shelf.

Give the land around the pond a wilder edge

Frogs and toads spend most of their lives on land, not in water, and this is the part of pond gardening most people overlook. A tidy, close-mown border offers nothing in the way of shelter, food or somewhere to sit out the winter.

• Let a strip of grass grow long next to the pond. Damp, tussocky grass is perfect daytime cover.
• Stack a log pile, stone pile or heap of dead leaves in a quiet corner. Toads and newts tuck into these to hibernate.
• Allow a compost heap and a patch of leaf litter to remain undisturbed through the winter months.
• Stop using slug pellets and garden insecticides anywhere near the pond. Amphibians eat slugs, and poisoned prey harms them too.
• Keep a route in and out – a gap under a fence or a rough, planted corridor helps amphibians move between neighbouring gardens.

Toads and newts have their own preferences

Common frogs are flexible and will use almost any pond with decent cover nearby. Common toads are fussier. They tend to favour larger, deeper, more established ponds, and they often return to the pond where they were born, sometimes travelling a kilometre or more to reach it. That journey is dangerous, so anything you can do to create damp, shaded, connected habitat between ponds helps enormously. Toads walk rather than hop, so they need cover to move through, not open ground.

Smooth and palmate newts also appreciate a garden pond, and they do best where there is plenty of submerged and floating plant cover, shallow margins for egg-laying, and no fish. Leave the pond to mature and it will steadily accumulate all three.

Looking after your residents through the year

Frog spawn usually appears in clumps from February onwards, while toad spawn follows a little later in long strings wound around plant stems. Tadpoles take roughly twelve to sixteen weeks to metamorphose, which means the pond should not be disturbed through spring and early summer.

• Never move spawn, tadpoles or adult amphibians between ponds. Diseases such as ranavirus and amphibian chytrid fungus spread this way and have caused serious declines.
• If the pond needs clearing, do it in late autumn and only part of it, leaving the rest as refuge.
• In a cold snap, do not smash the ice – the shock can kill amphibians resting below. Float a pan of hot water on the surface to melt a hole instead.
• Sweep up excess autumn leaves rather than letting the whole lot sink, and leave the netted debris on the bank for a day so any creatures can crawl back home.

Be patient. A new pond often sits quiet for a season before anything finds it, then one mild night in spring you will hear the low croaking that tells you the frogs have arrived. That first chorus is worth every bit of the digging.