Heuckenlock nature reserve

Heuckenlock nature reserve IUCN Category IV - Habitat / Species Management Area
View into the Heuckenlock at low water (2014)
location	Hamburg , Germany
surface	89 ha
WDPA ID	81874
Geographical location	53 ° 28 '  N , 10 ° 2'  E Coordinates: 53 ° 28 '28 "  N , 10 ° 2' 19"  E
Setup date	1977
administration	BUE

The Heuckenlock nature reserve is one of the last tideau forests in Europe. It is located in the south of the Hamburg Elbe island Wilhelmsburg near the Bunthäuser Spitze outside the flood protection systems and is therefore flooded about a hundred times a year by spring or storm surges . The area extends over a length of three kilometers along the north bank of the Süderelbe and has an area of ​​almost 100 hectares.

The nature reserve , together with the nature reserve " Schweenssand " on the south bank of the Süderelbe, forms the European FFH area "Heuckenlock / Schweenssand". Due to its special location between river and land, the Heuckenlock, designated as a nature reserve, is an important retreat for many plant and animal species.

Visitors to the Heuckenlock, which also offers a hiking trail, should find out about the water level of the Elbe beforehand, as parts or the entire area will be flooded if the water level is above the mean high tide.

Emergence

Freshwater mudflats Heuckenlock with running water

The Heukenlock at the highest water level

The Heuckenlock is located in the splitting area of the Elbe . The post-glacial rise in sea levels and the subsequent tidal backwater formed a landscape that was characterized by swamps and water wilderness. Today we find the most significant remaining area of ​​this tidal meadow landscape in the Heuckenlock. The area was and is still shaped by the strong tidal influence. Since ebb and flow act in the fresh water of the Elbe, we have the special feature of the fresh water tide alluvial forest, which can only be found between Glückstadt and Geesthacht and is unique in the world.

The Elbe water is rich in nutrient-rich suspended matter. With every flood a thin layer of this silt is deposited. This brings an enormous amount of nutrients to the area. This means that the plants in the Heuckenlock become particularly large. This supply of nutrients and the influence of ebb and flow are the prerequisites for the development of this particularly species-rich swamp and water wilderness.

Origin of the name

The Heuckenlock owes its name to the large creek in the area. "Dat Lock" stands in Low German for hole (or a valley filled with water) and "Heucke (n)" is the name of a family in Moorwerder who still own an area in the nature reserve today.

ecology

The Heuckenlock is three kilometers long and up to 400 meters wide. Up to 500 species of plants can be found on this area of ​​almost 100 hectares.

Vegetation zones

Depending on the altitude and thus the frequency and duration of flooding, typical alluvial forest vegetation zones can be identified.

In the lower lying areas of the nature reserve, which are most frequently and heavily flooded, various reed stands grow . These consist of the dominant, very vigorous and sometimes up to five meters high reed or thatch, but also, for example, narrow and broad-leaved cattails and cane grass. Even the purple loosestrife is found on the banks of creeks seams in larger communities.

The flood- flushing areas are populated by various vampires , knot oaks and sedges .

The tideau forest, characteristic of the Heuckenlock, is found on a firmer sandy bottom. In the wettest area it consists of various willow bushes. Transitioning to the somewhat drier areas, you will find the typical locations for different poplar species, alders and ash trees . Together with the willows, these tree species form the so-called softwood floodplain .

The so-called hardwood floodplain with the character tree species oak and white elm was established on the highest and therefore driest areas .

Due to the much stronger tidal range due to dykes and deepening of the shipping channels with more frequent flooding of the area, the hardwood floodplain has disappeared except for a few trees. Since the designated "Primeval Forest Heuckenlock" is not subject to forest use, trees in the alluvial forest can get very old here.

flora

The clearly oldest tree was a white elm with a trunk circumference of over four meters. It was probably over 400 years old. Due to its isolated location, it survived the great Dutch elm disease at the end of the 20th century, but did not survive hurricane Xaver in autumn 2013, which tore it in two and felled it. Both parts of the tree continue to sprout new shoots. The oldest shrub is an approximately 350-year-old eel-cap .

The gnarled polluted willows , which have to be cut regularly, are an old cultural asset . The cavities in their typically shaped heads offer shelter for insects and birds.

In Heuckenlock there are three meadows with chess flowers, which are rare in Hamburg . These only grow in meadows that are very humid, but they cannot tolerate standing water. Therefore, they grow here mainly on small elevations and knolls. Good site conditions are rarely found, which is why the checkerboard flowers are also endangered and must be protected. An annual mowing ensures the occurrence.

Hemlocks water fennel and Wibels Schmiele grow only in the freshwater tidal areas and therefore require special protection.

fauna

Due to the frequent flooding, there are few ground-breeding birds in the nature reserve, but almost exclusively tree and reed-breeders. Breeding birds that are at least occasionally encountered in the Heuckenlock include the puffy tit with its distinctive hanging nests, nightingale , long-eared owl , small woodpecker , reed warbler , reed warbler and reed bunting .

A pair of white-tailed eagles has lived in the nature reserve since 2008. The first attempt at breeding in 2011 was unsuccessful. The white-tailed eagle has been breeding successfully in the Heuckenlock since 2012 and raised one to three young birds every year (as of 2019). In April 2014, the eyrie toppled over in a storm, and no breeding success was possible that year.

Large bird colonies of gray herons and cormorants are no longer represented in the alluvial forest, the birds can only be found as foraging and resting in the nature reserve.

Creeks

Several creeks wind through the Heuckenlock, which fall dry twice a day at low tide . The largest creek, the "Heuckenlock", can be seen from the bridge of the hiking trail that leads through the area and the ebb and flow of tides can be observed. The tidal range in the priel is over 3.50 meters.

Moated castle

Until 2003, the last listed Vordeich farmhouse in Hamburg's urban area, the so-called Wasserburg, was in the Heuckenlock west of the A1 motorway. The farmhouse stood there on a terp , surrounded by a creek and was over 200 years old. It stood empty for a few years and was left to decay. A planned use as a nature conservation information center by the Society for Ecological Planning (GÖP) could no longer be financed after a fire in May 2001. In 2003 the ruin was removed. The summer dike of the Wasserburg-Koog has been opened so that the tide can swing in and out unhindered.

Landscape conservation measures

The Society for Ecological Planning eV is committed as a supervising association for the preservation of the landscape and biodiversity. This includes the removal of alien plants in the area, which make the habitat of the rare native flora contestable. The Japanese knotweed and the Indian balsam have developed into a problem here . In order to be able to preserve the chess flower population, three meadows are kept from being overgrown with reeds and tall perennials by mowing twice a year. In the winter months, maintenance of the polluted willows in the nature reserve is scheduled. Bank reinforcements were completely dismantled or reduced in bays and on a section in the east of the nature reserve. After the “moated castle” in the west of the nature reserve was demolished, the Society for Ecological Planning eV renatured the area by removing fortifications and soil seals, flooding the Koog by opening the summer dike and planting some oaks and white elms on the terp.

Web links

Commons : Heuckenlock  - collection of images, videos and audio files

• The Heuckenlock nature reserve - hamburg.de
• The Heuckenlock nature reserve - kulturost.de
• Ordinance on the Heuckenlock nature reserve of July 19, 1977

Individual evidence

1. ↑ 2526302 Heuckenlock / Schweenssand.  (FFH area) Profiles of the Natura 2000 areas. Published by the Federal Agency for Nature Conservation . Retrieved February 21, 2016.
2. ↑ For love of the green side of Hamburg | goep.hamburg | Society for ecological planning e. V. Accessed April 22, 2020 .