Discover the Hoge Berg

There are actually two sand quarries dug out of the flanks of the Hoge Berg. One of them is situated next to the Doolhof and is managed by Natuurmonumenten as a nature reserve for insects. The other lies slightly further north east, next to the Skillepaadje. This second quarry is in private ownership and is not managed as a nature reserve. The Zandkuil on the Hoge Berg is cherished by nature lovers as the burrows in the clay loam banks are inhabited by unusual insects.

Warm

“It can be so warm in the quarry! Precisely due to this warmth, the pit is a favourite home to thousands and thousands of mining bees and mining wasps, which go about their active, colourful and interesting lives there…The sand pit thanks its existence to large-scale sand extraction for the purpose of the construction of strong sea dykes…It is the most beautiful of all my quarries..” According to Jac. P. Thijsse in an article in ‘De levende natuur’, published in 1903.

Texel fan ‘avant la lettre’

Jac. P. Thijsse was head of the French School in Den Burg from 1889 to 1892. He wrote about this period himself: “Although I’ve only been living there for two and a half years, I will remain a Texelaar until the end.” He was extremely impressed by everything living in the natural environment on Texel and frequently returned to the island during the course of his life. He was often accompanied by his friend Eli Heimans, with whom he founded the Vereniging Natuurmonumenten (Dutch Society for the Nature Conservation) in 1905. Thijsse and Heimans together arranged for the Zandkuil to be bought by Natuurmonumenten in 1924, as the only nature reserve for insects in the Netherlands.

Solitary bees

The bees inhabiting the burrows in the Zandkuil are not honey bees. Mining bees are often referred to as ‘solitary’ bees, as they do not live in swarms. This also applies to mining wasps. Mining bees and mining wasps are beautiful creatures. There are many different species and the range of species is nowhere larger than in the Zandkuil on Texel. Above all, a couple of species are almost unique to Texel.

Food for offspring

Mining wasps lay an egg and a package of food in every burrow. This can be a dead fly, caterpillar or aphid. Mining bees place a little ball of pollen in the burrow for their offspring. And cuckoo bees lay their eggs in a burrow where a mining bee has already placed a supply of pollen.

Woodland day

For many years, two pavilions stood on the edge of the Zandkuil: Neptunus and Ceres. Owners of the pavilions often entertained their guests here on Sundays. Once a year, on the third day of Whitsun, many Texel families went to the Doolhof and the Zandkuil to romp around and have picknicks. This was known as ‘Bossiesdag’ (woodland day). An accidental but favourable advantage to all of this activity was that the slopes of the Zandkuil were scraped open in some places. This made it easier for the mining insects to dig their burrows.

Maintained by volunteers

When Texel started becoming busier, it was deemed time to close the Zandkuil to the general public. The insects would otherwise be disturbed all year round. To prevent the slopes becoming overgrown, insect specialist Ben Brugge now leads a group of volunteers from Kwadijkervlotbrug, who frequently visit for the necessary pruning and ground work.

Bee hotels

Insect fauna in the Zandkuil is not as diverse as it once was in Thijsse’s day. Species of wild flora have become significantly fewer and pesticides have taken their toll. Fortunately, an increasing number of farmers are sowing their field borders in with wildflowers.

People are also building extra opportunities for nesting. You now come across them more often: bee hotels. Holes of various diameters are drilled into all sorts of wood. These pieces of wood are put together as a ‘hotel’ which is often placed on a wooden pole or hung up on a wall. These kinds of measures can play a part in the restoration of insect fauna.