Signs of the approach of spring might be, for many species, a day of bright sunshine. For the amphibian population, however, the new season beckons on a damp, mild evening, with plenty of moisture in the air.

A temperature of more than six degrees, perhaps after a spell of rain, gives the green light for toads to set out on their annual migration from their winter hibernation grounds to the ancestral breeding ponds they have used every year since they were born.

Unfortunately, there is no corresponding red light to stop the traffic the toads are likely to encounter when their route crosses a busy road, so at known crossing points any help in the way of toad patrols can be essential for their safe progress.

For many years, Froglife, a national wildlife charity, has been organising, with the support of the Amphibian and Reptile Group UK (ARG-UK), a campaign to set up as many patrols as possible. It now has some 670 across the country.

In Oxfordshire, it has records of 19 crossing points, at which arrangements have been made for the official toad crossing signs to be in place during the migration season. Depending on the availability of volunteers, some are manned by toad patrollers at the most critical times.

Among the newest groups is that at Fawler, where two years ago Harriet and Matthew Kopinski acted on their concern for the toads they had seen on the road between Stonesfield and Charlbury.

Mrs Kopinski contacted Froglife, which can arrange for the registration of the crossing on the Department of Transport database once records have been provided of the presence of at least 100 toads in a season.

“Through knowing the area, I had been aware of the toads on the road there,” she said, “and somebody had already been giving them help in the past. When in 2006 I became aware of the full extent of the problem, and saw the bodies of all the toads, I contacted Froglife.

“The toads go to a big pond on one side of the road from the fields and woods on the other side where they have been spending the winter.

“They cross over on about a 100-yard stretch of the road. As soon as there is a wet night and it is not very cold, they all come out — and all at once, it seems.

“Unfortunately, that day is often a Saturday — when there is nobody else about.”

To enlist their first volunteers, Mr and Mrs Kopinski delivered notes through the letter boxes of houses in the neighbourhood. Although the response was at first very good, numbers have dropped off since.

By the second year, the Fawler group had recorded sufficient numbers of toads to enable them to be provided with the toad crossing signs by Oxfordshire County Council highways department, to be placed at the beginning and end of the crossing area. Mrs Kopinski estimates that last year the lives of about 150 toads were saved by their being helped to safety, with another 50 or so unavoidably becoming traffic victims.

Setting out with buckets, gloves, torches and high-visibility jackets, the rescuers pick up the toads approaching the roads and, as soon as it is safe to do so, carry them over to the other side.

“We start at dusk,” says Mrs Kopinski, “and stay out for at least a couple of hours. We find that motorists do slow down when they see us, and occasionally stop to ask what we are looking for.”

She has been supported in her activities by Jane Bowley, of the Wychwood Project. This year, she is planning to involve young volunteers in the new Wychwood V Project which encourages involvement in conservation activities by young people.

Alan Spicer, chairman of the Wychwood Project, is full of admiration for the dedication of the toad patrol teams.

The toads of Charlbury have their own champion, Alison Nicholls, who was instrumental in crossing signs being installed at the junction of Fishers Lane and Pools Lane.

She said: “When I used to walk to school with my children, I saw all the casualties. And I decided to do something about it.

“There is a particular pond in a garden which the toads use, and there are others in other nearby gardens. The toads apparently come along some unmade-up roads towards the main road, walk along it and then use a pipe to make their way into the garden.

“The owner of the pond has told us that some toads do stay there all the year round, while the others migrate to and fro annually. They clearly seem instinctively attracted to the same place, it is not a pond chosen at random.”

Although it is not always possible to keep a watch here for the crossing toads, Mrs Nicholls points out that the signs have a benefit for both here and elsewhere in the village.

“There are a lot of other places in Charlbury where the toads cross, and so the signs raise awareness of these as well,” she added.

A long-established rescue group is the Toaders, a group led by Mary Keyte, on a road between Ardington and Lockinge, near Wantage, and begun when she encountered lots of toad victims while travelling the roads making postal deliveries for the Royal Mail.

Always quick to take action when any creature is in need of help, Mrs Keyte enlisted the aid of the Lockinge Estate, which now puts up toad crossing signs each year at the appropriate points on its road boundaries.

Mrs Keyte and her friends and family have spent many evenings carrying out rescue missions over the years, using their buckets to carry the toads across the road to safety.

Both she and the organisers of the more recent patrols are finding that numbers are tending to be fewer as the years pass, and this is a major concern at Froglife.

It regards the main causes to be casualties during the migration, at a time of extensive development of the road network, and the loss of habitat, particularly of the traditional breeding ponds of the toads.

Froglife would like to receive information about any crossings not already recorded on its database, and for volunteers to be involved in patrols. Although numbers in the first year may not reach the 100 amphibians required for the official registration with the Department of Transport, they may do so in future years — and in the meantime another generation of toads may have had many of its members saved.

Froglife can provide advice about risk assessment before starting a patrol, for which road safety should always be paramount.

When the migration begins is entirely dependent on weather conditions. Mrs Keyte has found that it can even be in mid-January, and Mrs Kopinksi was told March 10 or 11, but both have found that February is most usual. It then continues at intervals until about the end of April.

Froglife is committed to the conservation of all amphibians and reptiles. Frogs and newts are among species for which there is concern about declining populations, and records of information about these are also welcomed. Frogs are not so fixed as toads about the ponds to which they migrate for breeding. There are many impediments to safety for all these creatures, among them high kerbs on pavements which they are unable to climb.

How do you tell the difference between a frog and a toad? Toads have a dry, warty skin and move chiefly by walking or crawling, sometimes with small hops. a frog has a more wet and slippery skin and hops or jumps. Contact Froglife on 01733 558844 or e-mail info@froglife.org