Report: ‘Protection of proof Coastal protection Ley Bay: Terrestrial invertebrates Hauener Hooge (1995-1999)»

Thanks to the construction project “Coast Protection Leybucht”, the Hauener Hooge, which was previously used as a summer polder, was subjected to profound changes. For the eastern part of the Hauener Hooge (hereinafter: “Hauener Hooge — Heller”) the opening of the summer dike as a secondary provision was included in the planning approval decision. This opening, which took place in autumn 1994, was intended to largely restore the natural saltwater influence in the area and thus, together with the simultaneous abandonment of grazing, contribute to the enhancement of the polder for nature conservation. The guiding principles for the former summer polder are use-free, low-interference and natural salt meadows and Priel structures. The western part (hereinafter: On the other hand, “Hauener Hooge — Inland”) was completely cut off from the influence of salt water as a result of the digging, so that further sweetening is expected to change vegetation and fauna. The NLÖ — Coastal Research Centre was established by the Weser-Ems District Government (Dec. 502), in consultation with the Aurich NLWK, by letter dated 18 December 1997 to continue the preservation of evidence and to initiate the second phase of investigation (1998-2000). [...] In order to document the changes expected as a result of the increased influence of saltwater after the summer dike opening and to monitor the success of the planned development of salt marshes, the invertebrates fauna at some representative sites was recorded in 1995-97 and 1999. Initial results of these studies have already been presented in interim reports (GÖTTING 1995, 1997). [...] A comprehensive overview of the evolution of vegetation throughout the Hauener Hooge up to 1999 is given by ARENS (2000), therefore this report does not intend to address the development of vegetation. In addition to the findings of 1999 concerning the above-mentioned invertebrates groups (walking beetle fauna, salt marsh flea cancer Orchestia gammarellus), this report also presents the stock developments of some spider groups from all years of study. Partial results of the investigations have already been evaluated in GÖTTING (2001). The second part of the report presents the invertebrates fauna of old salt marshes of the Ley Bay. With these comparative data, the long-term development potential of the dense summer polder areas is to be investigated. [...] A third part of the work covers the development of the invertebrates fauna located within the NSG Leyhörn, which has been cut off by the Hauener Hooge area since the discovery of saltwater influence in 1991. [...] The aim of this thesis is to answer the following questions: What changes in invertebrate fauna occurred in the leaked Hauener Hooge — Heller 1999 compared to the first investigation section? To what extent is the intended settlement of salt marsh species advanced? How is the colonisation of old Leybucht salt meadows of different uses with terrestrial invertebrates? Is this a development forecast for Hauener Hooge? To what extent does the invertebrate fauna correspond to the mission statement “wet grassland”? Which management measures can possibly contribute to the optimisation of the conditions found? [...]»