Gipskarstlandschaft Hainholz in Lower Saxony

The Hainholz is located in the South Harz karst region, about 5 km south of Osterode and near the village of Düna. The gypsum was formed at the end of the Palaeozoic era in the Upper Permian. In the course of the Earth's history, further rocks and sediments were deposited on the Zechstein, which was later uplifted along a length of about 100 km and a maximum width of three km on the southern edge of the Harz Mountains. After the last ice age 10,000 years ago, the present surface of this extraordinary karst area was formed; this process continues to this day. The gypsum near the surface aroused industrial desires. Gypsum was and still is mined in many valuable habitats, leaving deep scars in the landscape. Hainholz was removed from the potential extraction areas. Instead, massive intervention in the karst landscape is taking place elsewhere, and there is no end in sight. On a short, signposted tour of Hainholz, you can experience almost all the special features of the gypsum karst. You will find sinkholes overgrown with hart ’s-tongue, deep gorges, a karst spring, caves of various sizes where bats hibernate, and a periodic sinkhole lake. This structurally rich landscape with all its diverse fauna and flora never ceases to amaze.

Gabriele Hoffmann actively supports DINA in taking soil and vegetation samples. After completing her Abitur in 1976, she studied biology at the Julius-Maximilians-Universität Würzburg from 1977 - 1983, where she graduated with a diploma in geobotany as her main subject (minor subjects: biochemistry, genetics, and paleontology). At the adult education centres in Würzburg, Clausthal-Zellerfeld, and Osterode, she held courses entitled "What's blooming?", "Our trees in winter" and "Wild herbs in the kitchen". She also worked for two years at the Regional Environmental Education Centre Harz National Park. After that, she offered geological-palaeontological guided tours at the "HöhlenErlebnisZentrum Bad Grund". For three years, she took over the management of the local history museum in Obernfeld and wrote a comprehensive chronicle about the village. Since 2016, Gabriele Hoffmann has been a pensioner and works voluntarily for NABU Osterode. She also volunteers in many other areas, such as guided tours of the town or as a tutor for children with a migration background. Besides her grandchildren, literature, and music, gardening is her great passion.

Wolfgang Rackow, born in Bad Lauterberg, worked professionally in advertising, most recently as project manager for trade fairs. He has been a NABU member since 1984 and was the first chairman of NABU Osterode am Harz (www.nabu-oha.de) for 26 years. He is also a founding member of the NABU bat committee and has been the spokesperson of the NABU regional bat group for Lower Saxony for 23 years, as well as the spokesperson of the bat working group in the Altkreis Osterode am Harz for 35 years. For his tireless work, he was awarded all three of NABU Germany's honorary pins (bronze, silver, gold).

Early on, his relationship with bats also awakened an interest in insects, as bats cannot survive without spiders and insects as food. Projects such as recording mosquitoes in winter roosts, looking after mosquito traps in the field, and insect mortality, in general, prompted him to join the DINA project. His connection to the Hainholz National Park are the 29 existing karst caves, which have served as winter quarters for bats for decades

Comments on working at DINA:

"My job was to take soil samples. The meadow with the insect traps was always released for the cows in autumn. At the very beginning of my job, I had to wait until the cows were moved to another pasture. It was too risky to vie for the favour of the pasture with the curious young cows.

After I had a visit from walkers during the last sampling in autumn 2020, a wonderful calm set in towards evening, which I enjoyed very much in this beautiful landscape. This mood was underlined by soft light and the circling of the kites and buzzards above me.

Again and again, I was fascinated by the pair of trees standing right next to the survey area. The mighty three-trunked birch protected the smaller oak. In the meantime, the oak has grown into a respectable tree and will probably tower over its protector in the next few years." (G. Hoffmann)

"In October I was able to dismantle insect trap 1 because the wild boars had partly harvested the maize field and destroyed the trap in the process. Furthermore, I discovered an elephant hawk moth and a great green bush-cricket in trap 2. I am curious about the evaluation results. I noticed that the cows and cattle from the surrounding pastures were very interested in my activities. In August I found a beautiful pasture landscape with a flock of sheep, Limousin cattle, black and white heifers, and our special breed of the Red Harzer Höhenvieh from my friend Daniel Wehmeyer in the surrounding meadows." (W. Rackow)