Most bicycles stolen in Amsterdam don't leave the area: researchers

Bicycles stolen in Amsterdam mostly don’t leave the Amsterdam area, according to a study by MIT’s Senseable City Lab in collaboration with TU Delft. The researchers placed inexpensive GPS trackers in 100 second-hand bikes. Seventy of those bikes were stolen. They tracked the stolen bikes and found that 68 remained in the city or surrounds.

“I think the most surprising thing was that it’s happening locally,” said MIT researcher Fabio Duarte. “We thought bikes might be stolen and sent abroad. We found they are used in the same [locations]. If they’re stolen and sold, the new owner uses the bike in the same areas, probably without knowing it was stolen. There are so many bikes in Amsterdam; you’re likely never to know it was yours.”

About 11,000 bicycles are reported stolen in Amsterdam per year. The municipality estimates the actual number of stolen bikes to be around 28,500, though cycling advocates think it may be even higher at 80,000 per year.

With the municipality’s approval, the researchers installed low-cost trackers on 100 second-hand bicycles and locked them in public locations. They tracked the bicycles between June and November 2021. During that time, 70 of the bikes got stolen.

The team then tracked the movement of the stolen bikes. Sixty-eight of them remained in the local Amsterdam area. Three to six of them spent enough time in the vicinity of second-hand shops that the researchers concluded they were likely sold there.

Twelve other bikes went to locations identified as informal selling places for bicycles - “on the bicycle black market,” the researchers said. Another 22 of the stolen bikes moved along the same paths to such an extent that the researchers suspect they moved in the same “subnetwork” of stolen bikes.

“What we found is that we can indeed investigate this and say something about the level of organization by doing network analysis and really looking into the data,” researcher Titus Venverloo said. The study yielded valuable information about the nature of Amsterdam’s bike theft problem that could be applied to criminal investigations. He pointed out that the GPS trackers used are very inexpensive.

The researchers shared their results with Amsterdam officials. Amsterdam alderman Melanie van der Horst of traffic and transport called it valuable information. “Every year, the bikes of tens of thousands of Amsterdam residents are stolen,” Van der Horst said. “They must buy a new bike while their bike is sold again somewhere else in the city. This research makes it clear that part of bicycle theft is organized.”