Passive nature restoration of marine habitats (115951)

In the recent Marine Strategy Framework Directive assessment of the Danish seas in 2023, several of the seabed habitats were considered adversely affected and ”not in Good Environmental Status” (subGES). In the Skagerrak, mud habitats were considered in subGES due to bottom trawling, In the Kattegat mud habitats were adversely affected by bottom trawling and hypoxia, while in the Baltic Sea mud and sand habitats in subGES due to hypoxia. 

The aim of this project is to investigate and close knowledge gaps of how a sea area will recover with respect to climate, environmental and nature effects, after it is established as a Marine Protected Area (MPA) closed to fishing activities using mobile bottom contacting gears. It is of particular importance to understand how passive restoration based on recovery by natural processes will lead to increased environmental status (“miljøtilstand”) of the MPA and adjacent areas, how ecosystem function and services and the value of these will change, and how MPAs can support a green transition of the fishery sector in general. More specifically the study will focus on how the MPA ecosystem will change/recover after trawling closure with respect to four core elements:

1) Physical seabed habitats, environment and climate; Closure to fuel-intensive bottom trawling is expected to facilitate a shift to low fuel and impacting fisheries within the designated area, but documentation of the resulting climate footprint changes of fishery is limited.

2) Benthic fauna and fish biodiversity, source-sink functions; Natural recovery of seabed habitats and communities depends on degradation state of biodiversity and recruitment potential, however MPA processes supporting habitat restoration are complex and requires quantification.

3) Food web interactions between benthos, fish and mammals; The effects of bottom trawling go beyond the impacts on target species, as trawling also affect other components of the benthic ecosystem and the seabed itself.

4) Ecosystem functioning and services; Valuation of biodiversity and ecosystem services has become a central approach to evaluate policy interventions and ensure that diverse impacts on nature and people are taken into account.

The project results will contribute to evaluate the effect of the ban across biological descriptors and indicates in the water framework directive, as well as inform future decisions on environmental and fishery sector management.

Funding

The project is funded by The Danish Agricultural and Fisheries Agency.

Research area: Ecosystem based Marine Management
Research area: Population Genetics
Research area: Marine Living Resources
Research area: Marine Populations and Ecosystem Dynamics