It is that toads always look a bit sulky in our eyes. But the one now poking its head above the cast-iron grate looks decidedly triumphant. He has just climbed half a meter straight up from a street gully – a rainwater drain like you see in curbs everywhere – and is now calmly climbing out through a slot in the manhole cover.
This toad was lucky. He was closely monitored during a field trial. Moreover, he had an aid: a small ladder that had been specially installed in this pit to help toads climb out. Hundreds of thousands of his fellow amphibians – perhaps half a million to a million a year, in the Netherlands alone – are less fortunate. They wither away when they end up in a street gully and cannot climb out. Or they wash away into the sewer.
The estimates come from Ravon (Reptile Amphibian Fish Research Netherlands), the organization that is now conducting this field trial. Raymond Creemers from Ravon talks about it in the testing grounds of Radboud University in Nijmegen. Here, behind the enormous greenhouses, he has built three sandbox-like constructions, covered with chicken wire, to test which type of ladder helps the most toads out of the pit.
A bad year
And this is no trivial task, Creemers emphasizes in one of his test setups. These are enormous numbers. “That estimate of the number of victims is an extrapolation of data that volunteers collect across the country,” he says. “Every village and every city has its hotspots where many toads disappear into wells. A lady in Houten had saved three thousand toads from a well in one season.”
And toads, he emphasizes, don’t have it easy anyway. Their numbers have fallen by more than 40 percent in our country between 2008 and 2024. This is partly due to climate change, loss and fragmentation of habitat, pesticides and the decline of insects. “Colleagues see similar trends, including in Flanders, the United Kingdom and Switzerland,” notes Creemers. “And 2025 was a very bad year.”
The large losses in traffic and in street drains contribute to the problem. Frogs and salamanders also sometimes fall into the trap, Creemers says, but they are mainly toads. In the spring they move en masse to a pond or ditch to reproduce. That is the famous toad migration. But also during the rest of the year they are constantly ‘on the move’ through built-up areas, looking for places to feed. Creemers: “All those high curbs form a barrier for them. Toads and salamanders walk long distances through the gutter looking for a passage, and then fall into such a pit. Frogs much less so. They sometimes jump over the curbs.”
There are five species of toads in the Netherlands: the common toad, the natterjack toad, the garlic toad, the midwife toad and the yellow-bellied fire toad. The common toad is quite common, the other species are rarer. The yellow-bellied toad is the rarest amphibian in the Netherlands and only occurs in South Limburg, the northernmost point of its range.
Raymond Creemers at one of the test tanks.
Toads climb up.
Photos Dieuwertje Bravenboer
Slow death
Creemers lifts a wooden frame with chicken wire from one of the test tanks. A street gully has been dug into the tank. The researcher lifts up the heavy cast iron lid to show what such a well looks like on the inside. This street gully, the square type, is in fact a concrete box of about forty by forty centimeters and more than half a meter deep. The lid has holes at the top edge that open onto the street. Halfway down the side there is an opening, closed with a movable valve, through which abundant rainwater drains underground to the sewer. A path that ends up in the street gully often treads water in about twenty centimeters of water (unless it has not rained for a long time), far below street level. That means a slow death from starvation or exhaustion.
But not in this well. There is a plastic ladder mounted in the corner that runs from the bottom all the way to the edge. And toads, it immediately becomes apparent, know how to use that ladder flawlessly. Because the well in question is empty: the ten toads in this test tank have all climbed out of the well in the past 24 hours. They are now sheltering under a roof tile or under leaves, surrounded by juicy earthworms that Creemers has collected for them.
“Eight, nine, ten,” the researcher counts as he carefully picks up the toads and puts them in a bucket. “All ten complete.”
The second container contains a different type of street gully. This is a more modern pit, made of plastic, and – seen from above – round in diameter. There is also a plastic staircase here, the shape of which is adapted to the curve of the chamber. “This one is slightly less successful,” says Creemers, given the results of the past few days. During six days in October he tested three different stairs; with ten toads per well this gives statistically reliable results. “We have a 98 percent success rate with the angular steps, just over 80 percent with those with a curvature, and a second type with a curvature is also above 95 percent.” This last 24 hours, this last step has been 90 percent successful: one toad is still at the bottom of the hole. Creemers scoops it out with a landing net and places it with its peers in a second bucket.
He empties all three containers, collects the toads in separate buckets and then carefully releases them into the next well: all the toads move one spot in the test setup. “And at the end of the test I take them back to the forest.”
Resistant to pistons
These toads come from a nearby forest near the German border, where they are gradually preparing to go into winter rest. Unlike frogs, toads do not spend the winter in the mud of ditches, ponds or puddles, but on land, deeply buried in humus-rich forest floors. “Or in the Spoorkuil, a deepened area behind the railway,” Creemers points out with a wave of his arm. “From there, the toads walk through the neighborhood en masse every spring, to mate in the large pond further away.”
The toad problem is also clearly visible here in the neighborhood, he says. You will find dozens of dead toads on the road surface every morning. And hundreds of toads end up in wells here. “Fortunately, volunteers also come here to transfer toads and to remove them from the wells.” In the Netherlands there are no fewer than 119 working groups that work on amphibians all year round. “As a result, we now know quite well what the hotspots are in each city,” says Creemers. “A city like Nijmegen easily has around 100,000 street gullies, but we estimate that you can make a big difference with a few hundred adapted gullies.”
Toads in a Nijmegen well can climb up independently via a staircase.
Photo Dieuwertje Bravenboer
And by ‘adapted’ he means that a toad ladder has been installed: during production, by the street gully manufacturer, or afterwards, by a municipal worker. “That was done in no time, with just a few screws. But it does take some time.” And it has to be done right. “We recently had a whole batch where the steps were mounted at the back of the pit. Then the toad still can’t climb out and it literally hits its nose.” Another point of attention is that the steps should not come loose. It must remain firmly in place when sewer cleaners lower a large plunger into the pit to suck out leaves and road debris. “That’s why we test all these models here. Which ones are the most effective for the toads? But also: which ones stay in place best?”
The angular steps, which you attach in a corner of the square street gully, appear to be superior on all fronts. But yes, not all street gullies are square. “The most modern chambers are all round,” points out Creemers, who has one on his test site. “But look, there’s a kind of basket in there that you can lift out to remove the dirt. So amphibians get stuck behind that. And that basket doesn’t go well with a ladder.”
Grateful work
The whole thing is therefore a huge logistical puzzle that requires a lot of consultation and lobbying, Creemers emphasizes. “There is now one large manufacturer of street gullies who likes to contribute ideas. And he wants to work on his green image. But there are more manufacturers. Moreover, we also want to install stairs in existing gullies.”
This is the importance of the ‘Path out of the pit’ campaign. It makes money available for concrete projects, but above all it must put the subject on the agenda. And that is necessary, Creemers knows, because designing the ideal staircase is one thing, but deploying it successfully and on a large scale is another. “There’s a lot involved.”
Fortunately, there are many people who are passionate about the project, Creemers knows. “Especially in these times, with all that news that doesn’t make you any happier, it is very nice to be able to do something concrete. Something beautiful, that really works. It is very rewarding work to help those animals on their way again. And every rescued toad or salamander is one of them.”
Almost all toads manage to escape from square pits with a corner staircase.
Photo Dieuwertje Bravenboer
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