Iets over de landslakken van Fort Kwadijk

A brief survey of terrestrial snails and slugs was performed on the tiny remains of Fort Kwadijk, a never finished fortification belonging to the historic “Defence Line of Amsterdam” (municipality Zeevang, North-Holland, the Netherlands). It revealed the presence of 19 different species: 12 snails and 7 slugs. Most noteworthy was the presence of the invasive slug Tandonia sowerbyi, which had been reported only once before from one of the 42 other fortifications constituting the “Defence Line of Amsterdam”.