Q2 2020 – Stay Home (but don’t forget to take your camera along!)

As SARS-CoV-2 spoiled our Mediterranean travel plans in spring 2020, we spent a lot of time in our local playground called the “Eifel”, the name of the German part of the Ardennes mountain complex. This hilly area is characterized by cool, humid sub-Atlantic climate. Compared to the Mediterranean, biodiversity in Western Germany is quite low, as this area has been an arctic tundra only some 12k years ago. In the postglacial era, in particular mobile and flexible species were able to expand their distribution range northwards. Poor north, rich south! However, local geology has generated a diversified habitat patchwork in our area:

  1. The higher altitudes (up to 700 m) are covered with mountainous woodlands and meadows. These hills consist of some 400 million year old Devonian silicate rock with rather acidic soil.
  2. Interspersed in between the silicate rock, some limestone troughs are home for xerophilic species.
  3. The deep river valleys with their particularly warm local climate are habitat even for some sub-Mediterranean species.

In consequence of this habitat variety, the area has been identified as one of the 30 German hotspots within the national biodiversity strategy (see detailed map: https://biologischevielfalt.bfn.de/fileadmin/NBS/documents/Bundesprogramm/2_Hotspots/Detailkarten/hotspots14.pdf).

Our area with the places which can be reached within about 30 minutes. On the left, the Belgian border (which was a hard border, during lockdown)  is marked in yellow; top right, the Rhein river can be seen, the meanders bottom right are the Mosel river.
Our area with the places which can be reached within about 30 minutes. On the left, the Belgian border (which was a hard border, during lockdown) is marked in yellow; top right, the Rhein river can be seen, the meanders bottom right are the Mosel river.

With regard to lizards, it has to be mentioned that our area is populated by only three Lacertid species (Lacerta agilis, Podarcis muralis, Zootoca vivipara). Hence, a generalist approach including insects and plants seems more appropriate to give an impression of the local nature. As each time has its highlights, our picture galleries below are structured by months.

April - sunny days and frosty nights

April is the time when first spring flowers come up despite of the meadows frequently being covered by hoarfrost in the morning. It was exciting to watch nature subsequently re-emerging after winter.

1. High altitudes

The higher altitudes of our area are populated by only two repitle species: Zootoca vivipara and Anguis fragilis. Both species give birth to fully developed juveniles - laying eggs seems no good idea in this rough climate! The heathlands on acidic soil have their own flora with some atlantic species reaching their eastern distribution limit in our area.

2. Visiting the limestone areas

The limestone troughs with their warm microclimate are inhabited by 4 reptile species: Besides of Zootoca vivipara and Anguis fragilis, these are Lacerta agilis and Coronella austriaca.

Furthermore, the poor, xeric grasslands, which are used as extensive sheep pastures, are home for interesting spring flowers.

3. Short trip to Ahr Valley

The Ahr river, which  runs from central Eifel eastwards to the Rhine river, has digged a steep valley into the silicate rock. The valley slopes have some dry and warm habitats which are inhabited by Podarcis muralis which in Germany occurs in areas with favorable climate, only. The Ahr population is connected with the Wall Lizards from the Rhine valley. It belongs to subspecies brongniardii.

May - dry like summer

In early May, winter was back. Temperatures of -6 °C killed a lot of insects, and plants were damaged. However, nature recovers fast. The following weeks were warm and dry, but, due to permanent drought, vegetation grew extremely slow.

1. Spring in the high altitudes

Nature's creatures have to be tough in an area where frost and snow are still possible in May. Anyhow, this time of the year demonstrates impressively the power of nature with flowers sprouting in the heathlands and numerous insects which seem to appear "over night".

Being less popular than the limestone areas with their amazing vegetation, the heathlands on silicate soil have their own specific flora and fauna. Meanwhile, this habitat type is listed in the European Flora Fauna Habitat Directive (92 /43 /EEC) as "Species-rich Nardus grasslands, on siliceous substrates in mountain areas (and submountain areas , in continental Europe)". The German term for this is "Borstgrasrasen" - for sure one of the coolest words in German language!

2. Early summer in the xeric habitats

The limestone habitats and the warm river valleys can be hot like summer already in May. Hence, nature develops much faster compared to the mountain meadows. And a short trip to Ahr valley is always good when you are longing for reptiles.

June – Atlantic mix of rain and sun

The spring drought ended in early June and due to frequent rainfalls the landscape turned lush and green. Northern Atlantic summer...

1. highlights of the limestone areas

The limestone troughs in our area are famous for their numerous orchid species - a must for naturalists in early summer. Furthermore, the dolomite rocks of Gerolstein host a population of Podarcis muralis. This is remarkable, as most German populations of this species occur on schist or sandstone, but not on limestone - maybe, because this kind of rock doesn't store the heat very long. Anyway, the Gerolstein population seems to be vital.

2. Back to the mountain meadows!

Early June is the best time for the higher altitudes: The meadows aren't mowed or grazed by sheep yet and show their rich flora. Even in June, warm temperatures can be interrupted by foggy weather or a cold blowing wind. This rough climate generates a unique, magic atmosphere.